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Sample records for enlarged parietal foramina

  1. Genetics Home Reference: enlarged parietal foramina

    MedlinePlus

    ... parietal foramina is an inherited condition of impaired skull development. It is characterized by enlarged openings (foramina) ... that form the top and sides of the skull. This condition is due to incomplete bone formation ( ...

  2. Enlarged parietal foramina: a rare forensic autopsy finding.

    PubMed

    Durão, Carlos; Carpinteiro, Dina; Pedrosa, Frederico; Machado, Marcos P; Cunha, Eugénia

    2016-05-01

    Enlarged parietal foramina (EPF) are a quite rare developmental defect of the parietal bone which has to be distinguished from the normal small parietal foramina. We report a forensic case of an individual found in an advanced state of putrefaction in his own house with an undetermined cause of death. No evidence of trauma was observed, and the toxicological exam was negative. The victim was a 40-year-old man with a history of epilepsy. The large biparietal foramina, a rare anatomical variation and unusual autopsy finding, were observed at autopsy. The recognition of anatomical variations is important to avoid false interpretations and conclusions and has a significant potential as an identity factor, thus contributing to positive identification.

  3. [Mother and son with enlarged parietal foramina, persistent fetal vein, and ALX4 mutation].

    PubMed

    Morita, Motoaki; Nanba, Eiji; Adachi, Kaori; Ohno, Kousaku

    2016-05-01

    Enlarged parietal foramina (EPF) are rare congenital skull defects. These round or oval defects are situated on each parietal bone approximately 1 cm from the midline. Most patients with EPF have a positive family history. The condition is inherited as an autosomal dominant trait with relatively high, but not full, penetrance. Mutation in either MSX2 or ALX4 genes is associated with enlarged parietal foramina. Case 1 is a boy who was noticed to have a large anterior fontanelle, large posterior fontanelle, and widely opened sagittal suture at 2 months. During development, the anterior fontanelle and sagittal suture closed at 3 years and the posterior fontanelle subsequently divided into two foramina with ossification of the midline bridge by 4 years. The foramina were about 2.5 x 2.5 cm in diameter at 8 years. Case 2 is the 34-year-old mother of Case 1. She showed similar bone defects in her cranium, again about 2.5 x 2.5 cm in diameter. Neither patient showed any neurological symptoms. Genetic analysis revealed a mutation in the ALX4 gene in both patients, and magnetic resonance imaging showed a persistent falcine sinus and a hypoplastic straight sinus. Further evaluation revealed that the mother of Case 2 also had a mutation in the ALX4 gene, but no enlarged parietal foramina. Although high penetrance of this condition has been reported, this family suggests incomplete penetrance of this disorder. PMID:27349084

  4. Enlarged parietal foramina: a rare finding in a female Greek skull with unusual multiple Wormian bones and a rich parietal vascular network.

    PubMed

    Piagkou, Maria; Skotsimara, Georgia; Repousi, Elpida; Paraskevas, George; Natsis, Konstantinos

    2013-06-01

    Enlarged parietal foramina (>5 mm) is an extremely rare developmental defect of the parietal bone, which is distinguished from the normal small parietal foramina, as genes associated with this entity have been identified, suggesting that it is hereditary in nature. We describe a dry skull of a 35-year-old female, with enlarged parietal foramina symmetrically situated bilaterally, oval in shape, measuring 4.5 × 9.3 mm (right) and 4.9 × 9.2 mm (left) in size. The foramina coexisted with multiple Wormian bones in several sites of the skull. On the inner parietal bone surface, the anterior, posterior and lateral foramina's rims carried grooves, which were continuous with the middle meningeal vessels' branches, indicating that a rich vascular network existed around the foramina. These vascular grooves also notched the external table at the margin of the foramina, which suggests a potential communication between the meningeal and the scalp vessels. In addition, this vascular variation should be taken into consideration when performing surgical interventions in the area, because the large vascular supply to the foramina is a possible source of extensive bleeding. Moreover, the interaction of intracranial and extracranial veins and the fact that the blood flows in them in both directions, as they are valveless, could represent a possible pathway for infections to spread in the cranial cavity.

  5. Evolution of cranial blood drainage in hominids: enlarged occipital/marginal sinuses and emissary foramina.

    PubMed

    Falk, D

    1986-07-01

    Physiological studies of cranial blood flow in humans in reclining vs. upright postures suggest that selection for bipedalism was correlated with the establishment of epigenetic adaptations for delivering blood preferentially to the vertebral plexus of veins, depending upon momentary respiratory and postural constraints. The frequencies of vascular/osteological channels used to deliver blood to the vertebral plexus of veins were determined for samples of African pongids, various taxa of fossil hominids, and extant Homo sapiens. These channels include an enlarged occipital/marginal (O/M) sinus system, multiple hypoglossal canals, and foramina that conduct emissary veins: posterior condyloid, mastoid, occipital, and parietal. The African pongid, and therefore presumably the ancestral prebipedal hominoid, condition is characterized by low frequencies of all of these routes except multiple hypoglossal canals. The earliest known bipeds (Australopithecus afarensis) and robust australopithecines are characterized by fixation of enlarged O/M sinus systems. Robust australopithecines are also characterized by apparently low frequencies of mastoid and parietal foramina, and high frequencies of multiple hypoglossal canals and posterior condyloid foramina. In gracile australopithecines and subsequently living hominids, trends towards increased frequencies of mastoid and (later) parietal emissary foramina coincide with a trend towards decreased frequencies of an enlarged O/M sinus system and multiple hypoglossal canals. These findings suggest that selection for bipedalism initially resulted in epigenetic adaptations for routes to deliver blood to the vertebral plexus including an enlarged O/M sinus system and hypoglossal canals, but that the pressures underlying these adaptations relaxed as bipedalism became established, and other routes for delivering blood to the vertebral plexus of veins were either directly or indirectly selected for, perhaps in conjunction with a changing

  6. An Enlarged Parietal Foramen in the Late Archaic Xujiayao 11 Neurocranium from Northern China, and Rare Anomalies among Pleistocene Homo

    PubMed Central

    Xing, Song

    2013-01-01

    We report here a neurocranial abnormality previously undescribed in Pleistocene human fossils, an enlarged parietal foramen (EPF) in the early Late Pleistocene Xujiayao 11 parietal bones from the Xujiayao (Houjiayao) site, northern China. Xujiayao 11 is a pair of partial posteromedial parietal bones from an adult. It exhibits thick cranial vault bones, arachnoid granulations, a deviated posterior sagittal suture, and a unilateral (right) parietal lacuna with a posteriorly-directed and enlarged endocranial vascular sulcus. Differential diagnosis indicates that the perforation is a congenital defect, an enlarged parietal foramen, commonly associated with cerebral venous and cranial vault anomalies. It was not lethal given the individual’s age-at-death, but it may have been associated with secondary neurological deficiencies. The fossil constitutes the oldest evidence in human evolution of this very rare condition (a single enlarged parietal foramen). In combination with developmental and degenerative abnormalities in other Pleistocene human remains, it suggests demographic and survival patterns among Pleistocene Homo that led to an elevated frequency of conditions unknown or rare among recent humans. PMID:23527224

  7. Anatomical observations of the foramina transversaria.

    PubMed Central

    Taitz, C; Nathan, H; Arensburg, B

    1978-01-01

    Four hundred and eighty foramina transversaria in dry cervical vertebrae of 36 spines and in a number of dissections were studied and classified according to size, shape, and direction of their main diameter. A coefficient of roundness was then elaborated. The variations of foramina appear to follow a pattern at various vertebral levels. The possible factors (in addition to the embryological ones) involved in causing these variations-for example, mechanical stress, size, course, and number of vertebral vessels-were analysed. The importance of the correct interpretation of the variations in the foramina transversaria in radiographic or computerised axial tomography is discussed. The contribution of the present study to the understanding and diagnosis of pathological conditions related to the vertebral artery and its sympathetic plexus is stressed. Images PMID:632823

  8. Gingival Enlargement

    MedlinePlus

    ... 2017 Annual Meeting Orlando, FL Our Partners Gingival Enlargement Gingival (Gum) enlargement, also known as gingival hyperplasia or hypertrophy, is an abnormal overgrowth of gingival tissues. There ...

  9. Anterior Mandibular Lingual Foramina: An In Vivo Investigation

    PubMed Central

    Rastelli, Claudio; Leuter, Cinzia; Gatto, Roberto; Continenza, Maria Adelaide

    2014-01-01

    In descriptions of surgical procedures in mandible, often there is no mention of an anatomical variance, the genial spinal foramina, where nerves and vessels go through. Aim of this study is to investigate frequency, shape, and dimensions of these foramina. 56 computed tomography dentascans were analyzed with an implant planning software. The considered parameters were frequency, number, position, diameters, and length of canals; the collected data were inserted in a spreadsheet and statistically analyzed; therefore, they were compared with those found in the literature. The measurements agree with the ones found in earlier studies, except for the length of the inferior spinal canals, which resulted lesser than that found in the literature. The frequency of the inferior spinal foramina, the data related to the inferior spinal foramina diameter (cross scan), and the measurements related to the superior spinal foramina diameter (axial scan) resulted to be major compared to those reported in literature. These obtained results are clinically interesting because an implant planning software has been employed, daily used by operators, and that permits in vivo investigations. Furthermore, due to the possibility of hemorrhagic accidents in this mandibular region, these data are particularly interesting for all of the operators who make interventions in this area. PMID:25215238

  10. The clinical anatomy of accessory mental nerves and foramina.

    PubMed

    Iwanaga, Joe; Saga, Tsuyoshi; Tabira, Yoko; Nakamura, Moriyoshi; Kitashima, Sadaharu; Watanabe, Koichi; Kusukawa, Jingo; Yamaki, Koh-Ichi

    2015-10-01

    Since three-dimensional computed tomography was developed, many researchers have described accessory mental foramina. The anatomical and radiological findings have been discussed, but details of accessory mental nerves (AMNs) have only been researched in a small number of anatomical and clinical cases. For this article, we reviewed the literature relating to accessory mental foramina (AMFs) and nerves to clarify aspects important for clinical situations. The review showed that the distribution pattern of the AMN can differ according to the position of the accessory mental foramen, and the reported incidence of AMFs differs among observation methods. A review of clinical cases also revealed that injury to large AMF can result in paresthesia. This investigation did not reveal all aspects of AMNs and AMFs, but will be useful for diagnosis and treatment by many dentists and oral and maxillofacial surgeons.

  11. Occipital foramina development involves localised regulation of mesenchyme proliferation and is independent of apoptosis.

    PubMed

    Akbareian, Sophia E; Pitsillides, Andrew A; Macharia, Raymond G; McGonnell, Imelda M

    2015-06-01

    Cranial foramina are holes within the skull, formed during development, allowing entry and exit of blood vessels and nerves. Once formed they must remain open, due to the vital structures they contain, i.e. optic nerves, jugular vein, carotid artery, and other cranial nerves and blood vessels. Understanding cranial foramina development is essential as cranial malformations lead to the stenosis or complete closure of these structures, resulting in blindness, deafness, facial paralysis, raised intracranial pressure and lethality. Here we focus on describing early events in the formation of the jugular, carotid and hypoglossal cranial foramina that form in the mesoderm-derived, endochondral occipital bones at the base of the embryonic chick skull. Whole-mount skeletal staining of skulls indicates the appearance of these foramina from HH32/D7.5 onwards. Haematoxylin & eosin staining of sections shows that the intimately associated mesenchyme, neighbouring the contents of these cranial foramina, is initially very dense and gradually becomes sparser as development proceeds. Histological examination also revealed that these foramina initially contain relatively large-diameter nerves, which later become refined, and are closely associated with the blood vessel, which they also innervate within the confines of the foramina. Interestingly cranial foramina in the base of the skull contain blood vessels lacking smooth muscle actin, which suggests these blood vessels belong to glomus body structures within the foramina. The blood vessel shape also appears to dictate the overall shape of the resulting foramina. We initially hypothesised that cranial foramina development could involve targeted proliferation and local apoptosis to cause 'mesenchymal clearing' and the creation of cavities in a mechanism similar to joint cavitation. We find that this is not the case, and propose that a mechanism reliant upon local nerve/blood vessel-derived restriction of ossification may contribute

  12. An Anatomical Study of the Nutrient Foramina of the Human Humeral Diaphysis.

    PubMed

    Xue, Zichao; Ding, Haoliang; Hu, Chuanzhen; Xu, Haitao; An, Zhiquan

    2016-05-16

    BACKGROUND Understanding the nutrient foramina is critical to clinical practice. An insult to the nutrient foramina can be caused by trauma and/or surgical dissection and lead to devascularization and bad outcomes. Few studies have looked at the humerus, and no studies have described relative information of humeral nutrient foramen related to anatomical structures that might be located by palpable landmarks. In this study, we analyzed the anatomical features of the nutrient foramina of the diaphyseal humerus and provide a discussion of clinical relevance. MATERIAL AND METHODS We dissected 19 cadavers and analyzed the relative positions of the foramina and surrounding muscles, and the number, direction, diameter, and location of the nutrient foramina. Foramina index and a new landmark index were used to calculate the location. We compared the data from both sides and the relationships between transverse and longitudinal locations, diameter and total length, and foramina index and landmark index were also analyzed. RESULTS The humeri had one or two main nutrient foramina located in a small area between the coracobrachialis and brachial muscles and oriented toward the elbow. The mean diameter was 1.11±0.32 mm. The mean index and landmark index were 43.76±4.94% and 42.26±5.35%, respectively. There were no differences between sides in terms of diameter, length, or nutrient foramina index. There were no significant correlations between transverse and longitudinal locations or diameter and total length. The foramina index and landmark index showed strong positive correlation (r=0.994, p<0.0001). CONCLUSIONS Our study provides details about the nutrient foramina that will benefit clinicians who treat injuries and diseases of the humerus. Surgeons should be mindful of soft tissue in the foraminal area during surgical procedures.

  13. An Anatomical Study of the Nutrient Foramina of the Human Humeral Diaphysis

    PubMed Central

    Xue, Zichao; Ding, Haoliang; Hu, Chuanzhen; Xu, Haitao; An, Zhiquan

    2016-01-01

    Background Understanding the nutrient foramina is critical to clinical practice. An insult to the nutrient foramina can be caused by trauma and/or surgical dissection and lead to devascularization and bad outcomes. Few studies have looked at the humerus, and no studies have described relative information of humeral nutrient foramen related to anatomical structures that might be located by palpable landmarks. In this study, we analyzed the anatomical features of the nutrient foramina of the diaphyseal humerus and provide a discussion of clinical relevance. Material/Methods We dissected 19 cadavers and analyzed the relative positions of the foramina and surrounding muscles, and the number, direction, diameter, and location of the nutrient foramina. Foramina index and a new landmark index were used to calculate the location. We compared the data from both sides and the relationships between transverse and longitudinal locations, diameter and total length, and foramina index and landmark index were also analyzed. Results The humeri had one or two main nutrient foramina located in a small area between the coracobrachialis and brachial muscles and oriented toward the elbow. The mean diameter was 1.11±0.32 mm. The mean index and landmark index were 43.76±4.94% and 42.26±5.35%, respectively. There were no differences between sides in terms of diameter, length, or nutrient foramina index. There were no significant correlations between transverse and longitudinal locations or diameter and total length. The foramina index and landmark index showed strong positive correlation (r=0.994, p<0.0001). Conclusions Our study provides details about the nutrient foramina that will benefit clinicians who treat injuries and diseases of the humerus. Surgeons should be mindful of soft tissue in the foraminal area during surgical procedures. PMID:27180828

  14. Accessory mental foramina, incisive nerve plexus and lingual canals with unusual emergence paths: Report of two rare cases.

    PubMed

    Haghanifar, Sina; Poorsattar Bejeh Mir, Arash

    2015-01-01

    Being knowledgeable of neurovascularization of anterior mandible is crucial for successful local anesthesia and for safe minor and major oral surgeries of this part. The first case was 62 years old and was found to have two accessory mental foramina with buccal emergence on the left side and two accessory mental foramina with buccal and lingual emergence paths on the right side (overall five mental foramina). Incisive nerve plexus with multiple cephalic branching was obvious on both sides. The second case was 60 years of age and had two lingual foramina on the lingual side with two accessory foramina on the buccal side of the symphysis. Considering our findings, a pre-operation limited cone beam computed tomography is suggested to avoid inadvertent damage, especially when planning a surgery in the mandibular inter-mental region. PMID:25767360

  15. Breast enlargement in males

    MedlinePlus

    Gynecomastia; Breast enlargement in a male ... The condition may occur in one or both breasts. It begins as a small lump beneath the nipple, which may be tender. One breast may be larger than the other. Enlarged breasts ...

  16. Bilateral Osseous Interclinoid Bridges Associated with Foramina of Vesalius: A Case Report.

    PubMed

    Paraskevas, George; Nitsa, Zoi; Koutsouflianiotis, Konstantinos

    2015-07-01

    The current study displays a very rare combination of ossified interclinoid ligaments at the sella turcica region associated with bilateral foramina of Vesalius. In a macerated skull four osseous bars interconnecting the clinoid processes bilaterally were detected. Specifically, two bilateral osseous bars were observed bridging the gap between the anterior and middle clinoid processes forming the so called caroticoclinoid foramen on each side and two additional osseous bridges linked the anterior and posterior clinoid processes, bilaterally. Furthermore, two distinct bilateral foramina of Vesalius were documented just anterior and medial to the foramen ovale. The awareness of the osseous sellar bridges is crucial for the physician and especially the neurosurgeon since their presence may complicate the removal of clinoid processes and induce damage of the internal carotid artery and oculomotor nerves. Furthermore, the likely existence of the foramen of Vesalius may lead to transfer of an infected thrombus into the cranial cavity and complicate a percutaneous trigeminal rhizotomy.

  17. Enlarged Adenoids (For Parents)

    MedlinePlus

    ... Are Reading Upsetting News Reports? What to Say Vaccines: Which Ones & When? Smart School Lunches Emmy-Nominated Video "Cerebral Palsy: Shannon's Story" 5 Things to Know About Zika & Pregnancy Enlarged Adenoids KidsHealth > ...

  18. Enlarged prostate gland

    MedlinePlus

    ... enlarges in size in a process called benign hypertrophy, which means that the gland got larger without ... in several of the symptoms of benign prostatic hypertrophy, or BPH. Symptoms may include a slowed or ...

  19. Parietal cheiro-oral syndrome.

    PubMed

    Yasuda, Y; Watanabe, T; Ogura, A

    2000-12-01

    Cheiro-oral syndrome due to a parietal lesion has been reported in conjuction with a brain tumor, infarction and migraine. Only six reports of cheiro-oral syndrome due to a parietal infarction have been reported to date. We treated a 45-year-old woman with cheiro-oral syndrome due to a parietal infarction. Her sensory disturbance was characterized by paresthesia in the lower face and hand on the left side, and severe involvement of stereognosis and graphesthesia in the left hand. The pathogenesis of parietal cheiro-oral syndrome is discussed.

  20. Apraxia and the Parietal Lobes

    ERIC Educational Resources Information Center

    Goldenberg, Georg

    2009-01-01

    The widely held belief in a central role of left parietal lesions for apraxia can be traced back to Liepmann's model of a posterior to anterior stream converting mental images of intended action into motor execution. Although this model has undergone significant changes, its modern descendants still attribute the parietal contribution to the…

  1. Anatomic study of cranial nerve emergence and associated skull foramina in cats using CT and MRI.

    PubMed

    Gomes, Eymeric; Degueurce, Christophe; Ruel, Yannick; Dennis, Ruth; Begon, Dominique

    2009-01-01

    Magnetic resonance (MR) images of the brain of four normal cats were reviewed retrospectively to assess the emergence and course of the cranial nerves (CNs). Two-millimeter-thick images were obtained in transverse, sagittal, and dorsal planes using a 1.5 T unit. CN skull foramina, as anatomic landmarks for MR imaging, were identified by computed tomography performed on an isolated cat skull using thin wire within each skull foramen. Thin slice (1 mm slice thickness) images were obtained with a high-resolution bone filter scan protocol. The origins of CNs II, V, VII, and VIII and the group of IX, X, XI, and XII could be identified. The pathway and proximal divisions of CNs V were described. CNs III, IV, and VI were not distinguished from each other but could be seen together in the orbital fissure. CN V was characterized by slight contrast enhancement.

  2. Sensory syndromes in parietal stroke.

    PubMed

    Bassetti, C; Bogousslavsky, J; Regli, F

    1993-10-01

    We studied 20 patients with an acute parietal stroke with hemisensory disturbances but no visual field deficit and no or only slight motor weakness, without thalamic involvement on CT or MRI and found three main sensory syndromes. (1) The pseudothalamic sensory syndrome consists of a faciobrachiocrural impairment of elementary sensation (touch, pain, temperature, vibration). All patients have an inferior-anterior parietal stroke involving the parietal operculum, posterior insula, and, in all but one patient, underlying white matter. (2) The cortical sensory syndrome consists of an isolated loss of discriminative sensation (stereognosis, graphesthesia, position sense) involving one or two parts of the body. These patients show a superior-posterior parietal stroke. (3) The atypical sensory syndrome consists of a sensory loss involving all modalities of sensation in a partial distribution. Parietal lesions of different topography are responsible for this clinical picture, which probably represents a minor variant of the two previous sensory syndromes. Neuropsychological dysfunction was present in 17 patients. The only constant association was between conduction aphasia and right-sided pseudothalamic sensory deficit. We conclude that parietal stroke can cause different sensory syndromes depending on the topography of the underlying lesion. Sensory deficits can be monosymptomatic but never present as a "pure sensory stroke" involving face, arm, leg, and trunk together.

  3. Carotico-clinoid foramina and a double optic canal: A case report with neurosurgical implications

    PubMed Central

    Zdilla, Matthew J.; Cyrus, Leah M.; Lambert, H. Wayne

    2015-01-01

    Background: The lesser wing of the sphenoid is a clinically important structure, particularly with regard to its anatomical relationship with neurovascular structures including the optic nerve, ophthalmic artery, and internal carotid artery. Anterior clinoidectomy, a neurosurgical procedure utilized to access paraclinoid aneurysms and neoplasms, is often complicated by the presence of anatomical variants including the carotico-clinoid foramen and the accessory optic canal. Case Description: A rare case report is presented documenting the simultaneous occurrence of bilateral carotico-clinoid foramina and a unilateral accessory optic canal. Conclusion: The presence of an accessory optic canal may be misconstrued as a carotico-clinoid foramen or pneumatization of the anterior clinoid process, lesser sphenoidal wing, or optic strut. The case report documents two clinically important variant structures occurring ipsilaterally, each with the potential to masquerade as the other radiographically and present complications to both neurosurgeons and radiologists. Knowledge of the unique combination of anatomical variants presented in this report may prevent adverse surgical events during anterior clinoidectomy procedures including hemorrhage of the ophthalmic artery or internal carotid artery and subsequent vision loss or death. PMID:25657866

  4. Job Enlargement: A Multidimensional Process

    ERIC Educational Resources Information Center

    Donaldson, Lex

    1975-01-01

    An evaluation study into the effects of a job enlargement exercise indicates that the expected increases in satisfaction associated with greater work variety, novelty, and felt use of abilities were achieved. (Author/MLF)

  5. ANATOMICAL STUDY OF CRANIAL NERVE EMERGENCE AND SKULL FORAMINA IN THE HORSE USING MAGNETIC RESONANCE IMAGING AND COMPUTED TOMOGRAPHY.

    PubMed

    Gonçalves, Rita; Malalana, Fernando; McConnell, James Fraser; Maddox, Thomas

    2015-01-01

    For accurate interpretation of magnetic resonance (MR) images of the equine brain, knowledge of the normal cross-sectional anatomy of the brain and associated structures (such as the cranial nerves) is essential. The purpose of this prospective cadaver study was to describe and compare MRI and computed tomography (CT) anatomy of cranial nerves' origins and associated skull foramina in a sample of five horses. All horses were presented for euthanasia for reasons unrelated to the head. Heads were collected posteuthanasia and T2-weighted MR images were obtained in the transverse, sagittal, and dorsal planes. Thin-slice MR sequences were also acquired using transverse 3D-CISS sequences that allowed mutliplanar reformatting. Transverse thin-slice CT images were acquired and multiplanar reformatting was used to create comparative images. Magnetic resonance imaging consistently allowed visualization of cranial nerves II, V, VII, VIII, and XII in all horses. The cranial nerves III, IV, and VI were identifiable as a group despite difficulties in identification of individual nerves. The group of cranial nerves IX, X, and XI were identified in 4/5 horses although the region where they exited the skull was identified in all cases. The course of nerves II and V could be followed on several slices and the main divisions of cranial nerve V could be distinguished in all cases. In conclusion, CT allowed clear visualization of the skull foramina and occasionally the nerves themselves, facilitating identification of the nerves for comparison with MRI images.

  6. Benign fibrous histiocytoma of parietal bone: case report and review of the literature.

    PubMed

    Yang, Lili; Feng, Yan; Yan, Xu; Li, Yanhui; Bie, Li

    2015-01-01

    A benign fibrous histiocytoma with primary site of origin in the parietal bone has not yet been reported in the literature. We report here a case concerning a 12-year-old girl with a 14-month history of an enlarging parietal bone mass. The tumor was excised after removal of the cortical bone and resection of the tumor surrounding the cortical bone erosion using pre-plasticity titanium repair. Both postoperative histopathological examination and immunohistochemical analysis were consistent with a benign fibrous histiocytoma. No clinical or computed tomography (CT) radiological signs of tumor recurrence and/or metastasis were observed at 12 months. Although a primary benign fibrous histiocytoma of the parietal bone is a rare tumor, it should be considered as a potential diagnosis for any cranial tumor. Surgical intervention is the most effective treatment technique for a benign fibrous histiocytoma. PMID:25951848

  7. Gingival enlargement in partial hemifacial hyperplasia.

    PubMed

    Jagtap, Rasika Ravindra; Deshpande, Gaurav Shekhar

    2014-01-01

    Hemifacial hypertrophy is a rare developmental disorder, characterized by unilateral enlargement of facial tissues. The hemifacial hyperplasia is classified as true hemifacial hypertrophy and partial hemifacial hypertrophy. It is unilateral enlargement of viscerocranial condition in which not all structures are enlarged. We present a rare case of gingival enlargement in partial hemifacial hyperplasia highlighting the clinical and radiological findings with the corrective treatment offered for gingival enlargement.

  8. Extensive Gingival Enlargement in Siblings

    PubMed Central

    Pushpanshu, Kumar; Kaushik, Rachna; Sathawane, R. S.; Athawale, Ravi P.

    2012-01-01

    Gingival fibromatosis is characterised by varying degrees of fibrotic gingival overgrowth that can be caused by a variety of aetiological factors. Hereditary gingival fibromatosis (HGF) is a rare genetic disorder, characterised by a slowly progressive, benign enlargement of keratinised gingiva. The condition may be found in an autosomal dominant or autosomal recessive mode of inheritance, the former being more common. It usually develops as an isolated disorder but can be one feature of a multisystem syndrome. Accordingly, HGF has been divided into two forms: non-syndromic and syndromic. The gingival enlargement can be localised or generalised, but usually involves both arches. The authors describe a case of non-syndromic generalised severe HGF, involving the maxillary and mandibular arches in two brothers. This report focuses on the diagnosis, treatment, and control of the disease. The pattern of inheritance and histopathologic characteristics are also emphasised. PMID:23275852

  9. Prolonged rock climbing activity induces structural changes in cerebellum and parietal lobe.

    PubMed

    Di Paola, Margherita; Caltagirone, Carlo; Petrosini, Laura

    2013-10-01

    This article analyzes whether climbing, a motor activity featured by upward movements by using both feet and hands, generation of new strategies of motor control, maintenance of not stable equilibrium and adoption of long-lasting quadrupedal posture, is able to modify specific brain areas. MRI data of 10 word-class mountain climbers (MC) and 10 age-matched controls, with no climbing experience were acquired. Combining region-of-interest analyses and voxel-based morphometry we investigated cerebellar volumes and correlation between cerebellum and whole cerebral gray matter. In comparison to controls, world-class MC showed significantly larger vermian lobules I-V volumes, with no significant difference in other cerebellar vermian lobules or hemispheres. The cerebellar enlargement was associated with an enlargement of right medial posterior parietal area. The specific features of the motor climbing skills perfectly fit with the plastic anatomical changes we found. The enlargement of the vermian lobules I-V seems to be related to highly dexterous hand movements and to eye-hand coordination in the detection of and correction of visuomotor errors. The concomitant enlargement of the parietal area is related to parallel work in predicting sensory consequences of action to make movement corrections. Motor control and sensory-motor prediction of actions make the difference between survive or not at extreme altitude. PMID:22522914

  10. Progressive bilateral thinning of the parietal bones

    SciTech Connect

    Cederlund, C.G.; Andren, L.; Olivecrona, H.

    1982-03-01

    Observation of a case of progressive bilateral parietal thinning within a period of 14 years induced us to study skull films of 3 636 consecutive patients. Parietal thinning was found in 86 patients (2.37%). It was more common in women, with a sex ratio of 1:1.9. The mean age of the females was 72 years, and that of the males 63 years. Previous skull films of 25 of these patients were available and showed progression in 10. It is concluded that parietal thinning is a slowly progressive disease of middle-aged and old patients and is not an anatomical variant or congenital dysplasia of the dipole.

  11. Attentional functions of parietal and frontal cortex.

    PubMed

    Peers, Polly V; Ludwig, Casimir J H; Rorden, Chris; Cusack, Rhodri; Bonfiglioli, Claudia; Bundesen, Claus; Driver, Jon; Antoun, Nagui; Duncan, John

    2005-10-01

    A model of normal attentional function, based on the concept of competitive parallel processing, is used to compare attentional deficits following parietal and frontal lobe lesions. Measurements are obtained for visual processing speed, capacity of visual short-term memory (VSTM), spatial bias (bias to left or right hemifield) and top-down control (selective attention based on task relevance). The results show important differences, but also surprising similarities, in parietal and frontal lobe patients. For processing speed and VSTM, deficits are selectively associated with parietal lesions, in particular lesions of the temporoparietal junction. We discuss explanations based on either grey matter or white matter lesions. In striking contrast, measures of attentional weighting (spatial bias and top-down control) are predicted by simple lesion volume. We suggest that attentional weights reflect competition between broadly distributed object representations. Parietal and frontal mechanisms work together, both in weighting by location and weighting by task context.

  12. Enlarged Vestibular Aqueducts and Childhood Hearing Loss

    MedlinePlus

    ... Health Info » Hearing, Ear Infections, and Deafness Enlarged Vestibular Aqueducts and Childhood Hearing Loss On this page: ... more information about enlarged vestibular aqueducts? What are vestibular aqueducts? The inner ear Credit: NIH Medical Arts ...

  13. Enlarged prostate - what to ask your doctor

    MedlinePlus

    ... body? What does the prostate gland do? What causes the prostate gland to enlarge? Do many other men have prostate problems? How do I know my problem is not prostate cancer? What are the symptoms of an enlarged prostate? ...

  14. Parietal eye nerve in the fence lizard.

    PubMed

    EAKIN, R M; STEBBINS, R C

    1959-12-01

    A nerve from the parietal eye of the western fence lizard, Sceloporus occidentalis, is described as leaving inconspicuously from the third-eye and extending caudally under the dura mater and then ventrally along the left anterolateral surface of the epiphysis to the habenular commissure of the brain. The existence of a parietal nerve must be considered in interpreting the effects of parietalectomy. PMID:13819089

  15. Dramatic Cataplexy Improvement Following Right Parietal Surgery

    PubMed Central

    Fam, David J.; Shammi, Prathiba; Mainprize, Todd G.; Murray, Brian J.

    2015-01-01

    This is the case of a 34-year-old woman with severe narcolepsy with cataplexy who experienced a dramatic reduction in cataplexy symptoms after resection of a right parietal astrocytoma. The patient underwent detailed neurological exam, neuropsychological testing, polysomnography and multiple sleep latency testing following surgery. Citation: Fam DJ, Shammi P, Mainprize TG, Murray BJ. Dramatic cataplexy improvement following right parietal surgery. J Clin Sleep Med 2015;11(7):829–830. PMID:25902819

  16. Gastrin receptors on isolated canine parietal cells

    SciTech Connect

    Soll, A.H.; Amirian, D.A.; Thomas, L.P.; Reedy, T.J.; Elashoff, J.D.

    1984-05-01

    The receptors in the fundic mucosa that mediate gastrin stimulation of acid secretion have been studied. Synthetic human gastrin-17-I (G17) with a leucine substitution in the 15th position ((Leu15)-G17) was iodinated by chloramine T; high saturable binding was found to enzyme-dispersed canine fundic mucosal cells. /sup 127/I-(Leu15)-G17, but not /sup 127/I-G17, retained binding potency and biological activity comparable with uniodinated G17. Fundic mucosal cells were separated by size by using an elutriator rotor, and specific /sup 125/I-(Leu-15)-G17 binding in the larger cell fractions was highly correlated with the distribution of parietal cells. There was, however, specific gastrin binding in the small cell fractions, not accounted for by parietal cells. Using sequential elutriation and stepwise density gradients, highly enriched parietal and chief cell fractions were prepared; /sup 125/I-(Leu15)-G17 binding correlated positively with the parietal cell (r . 0.98) and negatively with chief cell content (r . -0.96). In fractions enriched to 45-65% parietal cells, specific /sup 125/I-(Leu15)-G17 binding was rapid, reaching a steady state at 37 degrees C within 30 min. Dissociation was also rapid, with the rate similar after 100-fold dilution or dilution plus excess pentagastrin. At a tracer concentration from 10 to 30 pM, saturable binding was 7.8 +/- 0.8% per 10(6) cells (mean +/- SE) and binding in the presence of excess pentagastrin accounted for 11% of total binding. G17 and carboxyl terminal octapeptide of cholecystokinin (26-33) were equipotent in displacing tracer binding and in stimulating parietal cell function ((/sup 14/C)aminopyrine accumulation), whereas the tetrapeptide of gastrin (14-17) had a much lower potency. Proglumide inhibited gastrin binding and selectively inhibited gastrin stimulation of parietal cell function.

  17. The Quadratojugal of Eryops studied by computed tomography and the morphological variability of foramina and canals in the quadratojugal of basal tetrapods.

    PubMed

    Čerňanský, Andrej; Witzmann, Florian; Klembara, Jozef; van Heteren, Anneke H

    2016-08-01

    With respect to its large size and abundance, Eryops is an important representative of Permo-Carboniferous basal tetrapods and one of the best-known large temnospondyl amphibians of this period. This taxon forms a significant component of the Early Permian tetrapod fauna of Texas and New Mexico and here we describe a new record of skull remains, the first one from Brushy Creek (30 km northeast of Seymour) in Texas (Petrolia Formation, Wichita Group; Lower Permian - lower Artinskian). Our material, found in 2015, consists of a left nasal, a jaw fragment (premaxilla or maxilla), left quadratojugal fragments, and a partial left mandible. We used computed tomography methods (micro-CT) for imaging both internal and external structures, for the first time, for Eryops. The quadratojugal presented here is exceptional compared to all known basal tetrapods in having four different internal foramina. CT data show that these foramina are interconnected by canals within the bone. This indicates that the morphology of the foramina and the course of the canals in the quadratojugal of basal tetrapods are more variable than hitherto thought. Anat Rec, 299:1073-1079, 2016. © 2016 Wiley Periodicals, Inc.

  18. The Quadratojugal of Eryops studied by computed tomography and the morphological variability of foramina and canals in the quadratojugal of basal tetrapods.

    PubMed

    Čerňanský, Andrej; Witzmann, Florian; Klembara, Jozef; van Heteren, Anneke H

    2016-08-01

    With respect to its large size and abundance, Eryops is an important representative of Permo-Carboniferous basal tetrapods and one of the best-known large temnospondyl amphibians of this period. This taxon forms a significant component of the Early Permian tetrapod fauna of Texas and New Mexico and here we describe a new record of skull remains, the first one from Brushy Creek (30 km northeast of Seymour) in Texas (Petrolia Formation, Wichita Group; Lower Permian - lower Artinskian). Our material, found in 2015, consists of a left nasal, a jaw fragment (premaxilla or maxilla), left quadratojugal fragments, and a partial left mandible. We used computed tomography methods (micro-CT) for imaging both internal and external structures, for the first time, for Eryops. The quadratojugal presented here is exceptional compared to all known basal tetrapods in having four different internal foramina. CT data show that these foramina are interconnected by canals within the bone. This indicates that the morphology of the foramina and the course of the canals in the quadratojugal of basal tetrapods are more variable than hitherto thought. Anat Rec, 299:1073-1079, 2016. © 2016 Wiley Periodicals, Inc. PMID:27224928

  19. Spatial updating in human parietal cortex

    NASA Technical Reports Server (NTRS)

    Merriam, Elisha P.; Genovese, Christopher R.; Colby, Carol L.

    2003-01-01

    Single neurons in monkey parietal cortex update visual information in conjunction with eye movements. This remapping of stimulus representations is thought to contribute to spatial constancy. We hypothesized that a similar process occurs in human parietal cortex and that we could visualize it with functional MRI. We scanned subjects during a task that involved remapping of visual signals across hemifields. We observed an initial response in the hemisphere contralateral to the visual stimulus, followed by a remapped response in the hemisphere ipsilateral to the stimulus. We ruled out the possibility that this remapped response resulted from either eye movements or visual stimuli alone. Our results demonstrate that updating of visual information occurs in human parietal cortex.

  20. Parietal Lobes in Schizophrenia: Do They Matter?

    PubMed Central

    Yildiz, Murat; Borgwardt, Stefan J.; Berger, Gregor E.

    2011-01-01

    Objective. Despite observations that abnormal parietal lobe (PL) function is associated with psychotic-like experiences, our knowledge about the nature of PL involvement in schizophrenia is modest. The objective of this paper is to investigate the role of the PL in schizophrenia. Method. Medline databases were searched for English language publications using the following key words: parietal lobe, combined with schizophrenia, lesions, epilepsy, cognition, rare genetic disorders, MRI, fMRI, PET, and SPECT, respectively, followed by cross-checking of references. Results. Imaging studies in childhood onset schizophrenia suggest that grey matter abnormalities start in parietal and occipital lobes and proceed to frontal regions. Although, the findings are inconsistent, several studies with patients at risk to develop schizophrenia indicate early changes in the PL. Conclusions. We want to propose that in a proportion of individuals with emerging schizophrenia structural and functional alterations may start in the PL and progress to frontal regions. PMID:22937268

  1. Posterior parietal cortex and developmental dyslexia.

    PubMed

    Jaśkowski, Piotr; Rusiak, Patrycja

    2005-01-01

    Dyslexia is defined as a specific reading disorder despite normal intelligence and conventional teaching. One of the most influential theories attempting to explain problems suffered by dyslexics assumes that dyslexia is caused by deficits of the magnocellular system. This system, generally responsible for processing fast sensory information, projects mostly to the parietal cortex. Consistent with this theory, dyslexics should have problems with tasks which specifically involve parietal cortex. In the article, we review data and show that, indeed, dyslexics have problems with fast attention shifts, show some symptoms of mild unilateral neglect syndrome and have abnormal saccadic and pursuit eye movements. Little is known about visuo-motor coordination and mental rotation, the tasks in which the parietal cortex is thought to play important roles.

  2. [Solitary fibrous tumor of the parietal pleura resected by video-assisted thoracic surgery; report of a case].

    PubMed

    Hayama, Makio; Maeda, Hiroya

    2010-06-01

    A 35-year-old male was admitted to our hospital for further examination of abnormal shadow on chest X-ray. Contrast-enhanced chest computed tomography (CT) showed a clear-shaped tumor with homogenous enhancement, measuring 25 x 20 mm in size, which had enlarged, compared with chest CT of 2 years before. The tumor appeared to be based partially on the parietal pleura. Under the diagnosis of solitary fibrous tumor (SFT) originated from the visceral or parietal pleura, video-assisted thoracic surgery (VATS) was performed. Under thoracoscopy, the tumor was pedunculated and arose from the parietal pleura. The tumor was resected completely. The pathologic findings revealed proliferation of spindle cells and collagen fibers without malignant aspects. Immuno-histochemical findings showed positive immunostaining for CD34 and vimentin in the tumor cells. These findings confirmed that the tumor was SFT.

  3. From visual affordances in monkey parietal cortex to hippocampo-parietal interactions underlying rat navigation.

    PubMed Central

    Arbib, M A

    1997-01-01

    This paper explores the hypothesis that various subregions (but by no means all) of the posterior parietal cortex are specialized to process visual information to extract a variety of affordances for behaviour. Two biologically based models of regions of the posterior parietal cortex of the monkey are introduced. The model of the lateral intraparietal area (LIP) emphasizes its roles in dynamic remapping of the representation of targets during a double saccade task, and in combining stored, updated input with current visual input. The model of the anterior intraparietal area (AIP) addresses parietal-premotor interactions involved in grasping, and analyses the interaction between the AIP and premotor area F5. The model represents the role of other intraparietal areas working in concert with the inferotemporal cortex as well as with corollary discharge from F5 to provide and augment the affordance information in the AIP, and suggests how various constraints may resolve the action opportunities provided by multiple affordances. Finally, a systems-level model of hippocampo parietal interactions underlying rat navigation is developed, motivated by the monkey data used in developing the above two models as well as by data on neurones in the posterior parietal cortex of the monkey that are sensitive to visual motion. The formal similarity between dynamic remapping (primate saccades) and path integration (rat navigation) is noted, and certain available data on rat posterior parietal cortex in terms of affordances for locomotion are explained. The utility of further modelling, linking the World Graph model of cognitive maps for motivated behaviour with hippocampal-parietal interactions involved in navigation, is also suggested. These models demonstrate that posterior parietal cortex is not only itself a network of interacting subsystems, but functions through cooperative computation with many other brain regions. PMID:9368931

  4. Conservative management of amlodipine influenced gingival enlargement

    PubMed Central

    Dhale, Rashmi P.; Phadnaik, Mangesh B.

    2009-01-01

    Gingival enlargement is a well recognized unwanted effect associated mainly with anticonvulsant drugs, immunosuppressant drugs and calcium channel blockers. Amlodipine influenced gingival enlargement is comparatively less prevalent amongst calcium channel blockers. It causes aesthetic disfigurement, speech disturbances, abnormal tooth movement and difficulty in mastication. The management of drug influenced gingival enlargement is a challenge for the periodontist, mainly due to less understanding of its pathogenesis, difficulties in selection of proper line of management and recurrence of the enlargement. This report discusses the importance of conservative approach (scaling and root planning along with drug replacement) in the management of a case of amlodipine influenced gingival enlargement. The need for extensive surgery was decreased after this approach. PMID:20376240

  5. Atrophy of the Parietal Lobe in Preclinical Dementia

    ERIC Educational Resources Information Center

    Jacobs, Heidi I. L.; Van Boxtel, Martin P. J.; Uylings, Harry B. M.; Gronenschild, Ed H. B. M.; Verhey, Frans R.; Jolles, Jelle

    2011-01-01

    Cortical grey matter atrophy patterns have been reported in healthy ageing and Alzheimer disease (AD), but less consistently in the parietal regions of the brain. We investigated cortical grey matter volume patterns in parietal areas. The grey matter of the somatosensory cortex, superior and inferior parietal lobule was measured in 75 older adults…

  6. The left parietal cortex and motor attention.

    PubMed

    Rushworth, M F; Nixon, P D; Renowden, S; Wade, D T; Passingham, R E

    1997-09-01

    The posterior parietal cortex, particularly in the right hemisphere, is crucially important for covert orienting; lesions impair the ability to disengage the focus of covert orienting attention from one potential saccade target to another (Posner, M. I. et al., Journal of Neuroscience, 1984, 4, 1863-1874). We have developed a task where precues allow subjects to covertly prepare subsequent cued hand movements, as opposed to an orienting or eye movement. We refer to this process as motor attention to distinguish it from orienting attention. Nine subjects with lesions that included the left parietal cortex and nine subjects with lesions including the right parietal cortex were compared with control subjects on the task. The left hemisphere subjects showed the same ability as controls to engage attention to a movement when they were forewarned by a valid precue. The left hemisphere subjects, however, were impaired in their ability to disengage the focus of motor attention from one movement to another when the precue was incorrect. The results support the existence of two distinct attentional systems allied to the orienting and limb motor systems. Damage to either system causes analogous problems in disengaging from one orienting/movement target to another. The left parietal cortex, particularly the supramarginal gyrus, is associated with motor attention. All the left hemisphere subjects had ideomotor apraxia and had particular problems performing sequences of movements. We suggest that the well documented left hemisphere and apraxic impairment in movement sequencing is the consequence of a difficulty in shifting the focus of motor attention from one movement in a sequence to the next. PMID:9364496

  7. Enlarged facial pores: an update on treatments.

    PubMed

    Dong, Joanna; Lanoue, Julien; Goldenberg, Gary

    2016-07-01

    Enlarged facial pores remain a common dermatologic and cosmetic concern from acne and rosacea, among other conditions, that is difficult to treat due to the multifactorial nature of their pathogenesis and negative impact on patients' quality of life. Enlarged facial pores are primarily treated through addressing associative factors, such as increased sebum production and cutaneous aging. We review the current treatment modalities for enlarged or dense facial pores, including topical retinoids, chemical peels, oral antiandrogens, and lasers and devices, with a focus on newer therapies. PMID:27529707

  8. Severe gingival enlargement associated with aggressive periodontitis.

    PubMed

    Padmanabhan, Shyam; Dwarakanath, C D

    2013-01-01

    Enlargement of the gingiva can be due to various causes. Most prevalent are the inflammatory type and drug-induced type of gingival hyperplasia. However, sever enlargement associated with an aggressive type of periodontitis is an infrequent finding. Reported here is a case of a female patient aged 18 years who presented with severe enlargement of the maxillary and mandibular gingiva. Examination revealed enlargement extending up to the incisal edge of all the teeth and also an associated generalized loss of attachment with radiographic evidence of reduced bone height resembling an aggressive type of periodontitis. There were no associated systemic signs and symptoms or any family history except that there was generalized vitiligo of the skin and oral mucous membrane. The case was treated by gross electrosection of the gingiva.

  9. Severe gingival enlargement associated with aggressive periodontitis

    PubMed Central

    Padmanabhan, Shyam; Dwarakanath, C. D.

    2013-01-01

    Enlargement of the gingiva can be due to various causes. Most prevalent are the inflammatory type and drug-induced type of gingival hyperplasia. However, sever enlargement associated with an aggressive type of periodontitis is an infrequent finding. Reported here is a case of a female patient aged 18 years who presented with severe enlargement of the maxillary and mandibular gingiva. Examination revealed enlargement extending up to the incisal edge of all the teeth and also an associated generalized loss of attachment with radiographic evidence of reduced bone height resembling an aggressive type of periodontitis. There were no associated systemic signs and symptoms or any family history except that there was generalized vitiligo of the skin and oral mucous membrane. The case was treated by gross electrosection of the gingiva. PMID:23633785

  10. Idiopathic gingival enlargement and its management

    PubMed Central

    Shetty, Arvind K.; Shah, Hardik J.; Patil, Mallika A.; Jhota, Komal N.

    2010-01-01

    Idiopathic gingival enlargement is a proliferative fibrous lesion of the gingival tissue that causes esthetic and functional problems. Both genetically and pharmacologically induced forms of gingival enlargement exist. This case report addresses the diagnosis and treatment of a case of idiopathic gingival enlargement in a 13-year-old female. The patient presented with generalized diffuse gingival enlargement involving the maxillary and mandibular arches extending on buccal and lingual/palatal surfaces and covering incisal / occlusal third of the tooth resulting in difficulty in speech and mastication since last three years. Patient also gave a history of surgical treatment being carried out four years back in upper anterior region suggesting of recurrence. Biopsy report confirmed the diagnosis of gingival hyperplasia. Gingivectomy was carried out in all four quadrants by using four different methods. PMID:21731254

  11. Non-focal enlargement in pancreatic carcinoma

    SciTech Connect

    Wittenberg, J.; Simeone, J.F.; Ferrucci, J.T. Jr.; Mueller, P.R.; van Sonnenberg, E.; Neff, C.C.

    1982-07-01

    Pancreatic adenocarcinoma can appear radiographically as enlargement of the major part of the pancreas. In this series, part or all of three or more pancreatic segments (head, neck, body, and tail) were involved in 27% of patients with adenocarcinoma who had computed tomography. Differentiation from pure pancreatitis may require additional radiographic studies. The varied tissue composition of a pancreas enlarged by adenocarcinoma will often require biopsy of multiple sites for confirmation.

  12. Extraocular muscle enlargement: a CT review

    SciTech Connect

    Rothfus, W.E.; Curtin, H.D.

    1984-06-01

    Extraocular muscle enlargement can result from a wide variety of disease processes. Although observations of the pattern of muscle involvement, muscle shape and enhancement, superior ophthalmic vein and cavernous sinus enlargement, sinus and bony wall abnormalities, and proptosis can lead to a limited differential diagnosis in some cases, no radiographic finding in itself seems to be pathognomonic. Correlative clinical findings are necessary to make a secure diagnosis.

  13. Autologus parietal grafts in preprosthethic surgery

    PubMed Central

    GHERLONE, E.F.; VINCI, R.; D’AVERSA, L.

    2010-01-01

    SUMMARY Edentulous patients usually request implant supported/fixed rehabilitation. Ridge resorption after teeth loss usually affect three-dimensional implant position. Vertical and/or horizontal bone augmentation procedures are often the only choice the clinician has to deliver prosthetic guided restoration. Gold standard for augmentation procedures such as sinus lift, onlay or inlay grafts, is still autologous bone. The patient in this report underwent a pre-prosthetic reconstruction of the jaws with parietal bone, followed by fixtures insertion and fixed prosthetic rehabilitation. This clinical report aims to underline the importance of multidisciplinary treatment to optimize the results of the rehabilitation. PMID:23285358

  14. Navigating from hippocampus to parietal cortex

    PubMed Central

    Whitlock, Jonathan R.; Sutherland, Robert J.; Witter, Menno P.; Moser, May-Britt; Moser, Edvard I.

    2008-01-01

    The navigational system of the mammalian cortex comprises a number of interacting brain regions. Grid cells in the medial entorhinal cortex and place cells in the hippocampus are thought to participate in the formation of a dynamic representation of the animal's current location, and these cells are presumably critical for storing the representation in memory. To traverse the environment, animals must be able to translate coordinate information from spatial maps in the entorhinal cortex and hippocampus into body-centered representations that can be used to direct locomotion. How this is done remains an enigma. We propose that the posterior parietal cortex is critical for this transformation. PMID:18812502

  15. Carcinoma of the lungs causing enlarged kidneys.

    PubMed

    Srisung, Weeraporn; Mankongpaisarnrung, Charoen; Warraich, Irfan; Sotello, David; Yarbrough, Shannon; Laski, Melvin

    2015-04-01

    Bilateral enlarged kidneys can be caused by a number of conditions. Renal metastasis is included in the differential diagnosis. We report a case of a 67-year-old woman with a 6-month history of productive cough and unintentional weight loss. Cavitary pulmonary lesions and bilateral enlarged kidneys were noted on imaging studies. Hematuria, azotemia, and proteinuria were present. Renal biopsy showed squamous carcinoma cells invading normal-appearing glomeruli and atrophic tubules. The invasive squamous cells stained negative for CK7 and CK 20. Lung biopsy confirmed squamous cell carcinoma. Our case shows that in patients with renal enlargement, even with the absence of a focal mass, renal metastasis should be considered, especially in those with suspected or diagnosed malignancy elsewhere. PMID:25829660

  16. Atypical And Severe Enlargement Of Right Atrium.

    PubMed

    Siniscalchi, Carmine; Rossetti, Pietro; Rocci, Anna; Rubino, Pasquale; Basaglia, Manuela; Gaibazzi, Nicola; Quintavalla, Roberto

    2016-01-01

    A 76 year-old woman was admitted to the Emergency Department for recent-onset dyspnea and cough. The electrocardiogram was considered inconclusive. A thoracic X-ray showed global cardiac profile enlargement. Computed tomography, acutely performed in the clinical suspicion of atypical pneumonia/myocarditis or pericardial effusion, showed cardiac enlargement especially of the right chambers. In order to investigate Ebstein's anomaly, pericardial cysts, tumors or other conditions of the right heart a simple trans-thoracic echocardiogram was performed. Four chambers view showed a giant right atrium aneurysm with moderate tricuspid regurgitation without stenosis or typical Ebstein's echocardiographic pattern. PMID:27649002

  17. Atypical And Severe Enlargement Of Right Atrium.

    PubMed

    Siniscalchi, Carmine; Rossetti, Pietro; Rocci, Anna; Rubino, Pasquale; Basaglia, Manuela; Gaibazzi, Nicola; Quintavalla, Roberto

    2016-01-01

    A 76 year-old woman was admitted to the Emergency Department for recent-onset dyspnea and cough. The electrocardiogram was considered inconclusive. A thoracic X-ray showed global cardiac profile enlargement. Computed tomography, acutely performed in the clinical suspicion of atypical pneumonia/myocarditis or pericardial effusion, showed cardiac enlargement especially of the right chambers. In order to investigate Ebstein's anomaly, pericardial cysts, tumors or other conditions of the right heart a simple trans-thoracic echocardiogram was performed. Four chambers view showed a giant right atrium aneurysm with moderate tricuspid regurgitation without stenosis or typical Ebstein's echocardiographic pattern.

  18. Aortic Annular Enlargement during Aortic Valve Replacement

    PubMed Central

    Dumani, Selman; Likaj, Ermal; Dibra, Laureta; Llazo, Stavri; Refatllari, Ali

    2016-01-01

    In the surgery of aortic valve replacement is always attempted, as much as possible, to implant the larger prosthesis with the mains goals to enhance the potential benefits, to minimise transvalvular gradient, decrease left ventricular size and avoid the phenomenon of patient-prosthesis mismatch. Implantation of an ideal prosthesis often it is not possible, due to a small aortic annulus. A variety of aortic annulus enlargement techniques is reported to avoid patient-prosthesis mismatch. We present the case that has submitted four three times open heart surgery. We used Manouguian technique to enlarge aortic anulus with excellent results during the fourth time of surgery. PMID:27703574

  19. Atrophy of the parietal lobe in preclinical dementia.

    PubMed

    Jacobs, Heidi I L; Van Boxtel, Martin P J; Uylings, Harry B M; Gronenschild, Ed H B M; Verhey, Frans R; Jolles, Jelle

    2011-03-01

    Cortical grey matter atrophy patterns have been reported in healthy ageing and Alzheimer disease (AD), but less consistently in the parietal regions of the brain. We investigated cortical grey matter volume patterns in parietal areas. The grey matter of the somatosensory cortex, superior and inferior parietal lobule was measured in 75 older adults (38 cognitively stable and 37 individuals with cognitive decline after 3 years). Dementia screening 6 years after scanning resulted in nine AD cases from the cognitively stable (n=3) and cognitive decline group (n=6), who were assigned to a third group, the preclinical AD group. When regional differences in cortical volume in the parietal lobe areas were compared between groups, significant differences were found between either the cognitive decline or stable group on the one hand and preclinical AD individuals on the other hand in the inferior parietal lobule. Group membership was best predicted by the grey matter volume of the inferior parietal lobule, compared to the other parietal lobe areas. The parietal lobe was characterised by a differential atrophy pattern based on cognitive status, which is in agreement with the 'last-developed-first-atrophied' principle. Future studies should investigate the surplus value of the inferior parietal lobe as a potential marker for the diagnosis of AD compared to other brain regions, such as the medial temporal lobe and the prefrontal lobe. PMID:21130554

  20. Endodontic treatment of a C-shaped mandibular second premolar with four root canals and three apical foramina: a case report

    PubMed Central

    Bertrand, Thikamphaa

    2016-01-01

    This case report describes a unique C-shaped mandibular second premolar with four canals and three apical foramina and its endodontic management with the aid of cone-beam computer tomography (CBCT). C-shaped root canal morphology with four canals was identified under a dental operating microscope. A CBCT scan was taken to evaluate the aberrant root canal anatomy and devise a better instrumentation strategy based on the anatomy. All canals were instrumented to have a 0.05 taper using 1.0 mm step-back filing with appropriate apical sizes determined from the CBCT scan images and filled using a warm vertical compaction technique. A C-shaped mandibular second premolar with multiple canals is an anatomically rare case for clinicians, yet its endodontic treatment may require a careful instrumentation strategy due to the difficulty in disinfecting the canals in the thin root area without compromising the root structure. PMID:26877993

  1. Malignant pilomatricoma in the parietal area.

    PubMed

    Kondo, Takeshi; Tanaka, Yoshio

    2006-01-01

    A 27-year-old Japanese woman presented with a 2.5-cm nodular subcutaneous lesion in the parietal area. The nodule was well demarcated and situated in the dermis and subcutis. Histologically, the tumor was diagnosed as malignant pilomatricoma. The tumor was excised, the postoperative course was uneventful, no evidence of local recurrence or distant metastasis was observed, and the patient continues to be under close follow-up. Malignant pilomatricoma, a locally aggressive counterpart of benign pilomatricoma, is also referred to as pilomatrix carcinoma. Most cases are excised as benign tumors; however, when the excision is incomplete local recurrence is likely, and distant metastases have also been reported. Histologically, the diagnosis can be challenging because no clear histologic criteria are available. Because of the rarity of malignant pilomatricoma, no welldefined standards in the surgical management of this neoplasm have been established. Moreover, since distant metastases have been described, close followup of the lesion is requisite.

  2. The pathology of parietal pleural plaques

    PubMed Central

    Roberts, G. Hefin

    1971-01-01

    The incidence, morbid anatomy, histology, and relationship of hyaline pleural plaques to exposure to asbestos has been studied. Plaques were found in 12·3% of 334 hospital necropsies (in an urban population in Glasgow, 41 cases). In 85·3% (35 cases) asbestos bodies were found in the lungs. There is evidence of a dose-response relationship between the number of asbestos bodies found in the lungs and the presence of pleural plaques. The selective distribution of plaques within the pleural cavities suggests that mechanical factors play a part in their localization. Histological examination contributed little to understanding the mechanism of plaque formation; that asbestos bodies have been detected in only a few cases suggest that their presence in the parietal pleura is not essential to plaque formation. The suggested mechanisms of plaque formation are discussed. Images PMID:5556121

  3. Hearts and Flowers: Learning To Enlarge Images.

    ERIC Educational Resources Information Center

    Kalil, Judy

    2003-01-01

    Describes a lesson that teaches kindergarten students how to enlarge a smaller drawing onto a bigger piece of paper. Explains that the students create their heart-shape designs using tempera paint and pastels in the larger picture. Includes a list of materials. (CMK)

  4. Enlarging the Vision of Art Therapy Research.

    ERIC Educational Resources Information Center

    McNiff, Shaun

    1998-01-01

    Before responding to papers in "Special Issue on Art Therapy and Research" (v15 n1), a context, including core principles, was established to generate dialog on research issues in art therapy. Sections are entitled "A Framework,""Inclusive Science,""Consensual Outcomes,""Enlarging the Vision of Research,""Aesthetic Measures," and "Integrating…

  5. Benign fibrous histiocytoma of the fronto-temporo-parietal region: a case report and review of the literature.

    PubMed

    Chen, Hongxu; Li, Pengcheng; Liu, Zhiyong; Xu, Jianguo; Hui, Xuhui

    2015-01-01

    Primary benign fibrous histiocytoma (BFH) at the skull is extremely rare. Here we report a case of a 22-year-old man presented with a 1-year history of progressive enlargement subcutaneous mass on the right side of the fronto-temporo-parietal region without symptoms. The tumor was radical resected through craniotomy and the bone defect was repaired by pre-plasticity titanium mesh. Histopathologic examination confirmed a benign fibrous histiocytoma, and no signs of tumor recurrence were detected at 3-year follow-up. PMID:26823894

  6. Mandatory Housing Requirements: The Constitutionality of Parietal Rules

    ERIC Educational Resources Information Center

    Iowa Law Review, 1975

    1975-01-01

    Analyzes the validity of parietal rules under both the due process and equal protection clauses of the Fourteenth Amendment. Models of substantive due process and equal protection are developed and applied to the various types of parietal rules that have been implemented at universities throughout the nation. (Author/JT)

  7. Enlarged pancreas: not always a cancer.

    PubMed

    Calculli, Lucia; Festi, Davide; Pezzilli, Raffaele

    2015-02-01

    Pancreatic fat accumulation has been described with various terms including pancreatic lipomatosis, pancreatic steatosis, fatty replacement, fatty infiltration, fatty pancreas, lipomatous pseudohypertrophy and nonalcoholic fatty pancreas disease. It has been reported to be associated with type 2 diabetes mellitus, acute pancreatitis, pancreatic cancer and the formation of pancreatic fistula. The real incidence of this condition is still unknown. We report a case of pancreatic steatosis in a non-obese female patient initially diagnosed with a mass in the head of the pancreas. Magnetic resonance imaging (MRI) was carried out to define the characteristics of the pancreatic mass. MRI confirmed the diagnosis of fat pancreas. Enlarged pancreas is not always a cancer, but pancreatic steatosis is characterized by pancreatic enlargement. MRI could give a definite diagnosis of pancreatic steatosis or cancer.

  8. Enlargement of salivary glands in bulimia.

    PubMed

    Vavrina, J; Müller, W; Gebbers, J O

    1994-06-01

    We report a unusual case of bulimia nervosa with bilateral swelling of parotid and submandibular glands as the only symptom of the underlying behavioural disorder. Histologically, sialadenosis was diagnosed in a parotid biopsy. The parotomegaly in bulimia may be a diagnostic primer as these patients often deny their eating disorder. B-scan ultrasonography is an important diagnostic tool to assess the nature of the parotid enlargement. Hyperamylasaemia occurs commonly in bulimic patients and may help to confirm the diagnosis. All patients with suspected bulimia should have a thorough medical history and physical examination to rule out other aetiologies of asymptomatic parotid swelling. As the enlargement is usually transient surgical intervention is only rarely required.

  9. Calcium channel blocker-induced gingival enlargement.

    PubMed

    Livada, R; Shiloah, J

    2014-01-01

    Despite the popularity and wide acceptance of the calcium channel blockers (CCBs) by the medical community, their oral impact is rarely recognized or discussed. CCBs, as a group, have been frequently implicated as an etiologic factor for a common oral condition seen among patients seeking dental care: drug-induced gingival enlargement or overgrowth. This enlargement can be localized or generalized, and can range from mild to extremely severe, affecting patient's appearance and function. Treatment options for these patients include cessation of the offending drug and substitution with another class of antihypertensive medication to prevent recurrence of the lesions. In addition, depending on the severity of the gingival overgrowth, nonsurgical and surgical periodontal therapy may be required. The overall objective of this article is to review the etiology and known risk factors of these lesions, their clinical manifestations and periodontal management.

  10. Successfully use agglomeration for size enlargement

    SciTech Connect

    Pietsch, W.

    1996-04-01

    The processing of fine and ultrafine particles by size enlargement finds an ever increasing application. At the same time, undesirable agglomeration such as buildup, caking, bridging, and uncontrolled aggregation of fine particles can occur during processing and handling of these particulate solids. This article will provide a survey of the phenomena of agglomeration and discuss the unit operation of size enlargement by agglomeration. This article is also an invitation, particularly to young engineers, to become interested in agglomeration. Considering that mechanical process technologies are requiring more energy every year than any other group of consumers and efficiencies are typically in the single digits or teens at best, considerable rewards can be expected from the development of scientifically modified, more energy-efficient methods and equipment.

  11. Enlarging mediastinal/hilar lymphadenopathy with calcification.

    PubMed

    Adachi, Takashi; Nakahata, Masashi; Moritani, Suzuko; Iida, Hiroatsu; Ogawa, Kenji

    2016-02-01

    A 77-year-old man was referred to our hospital due to enlarging mediastinal/hilar lymphadenopathy with calcification. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and bone marrow aspiration were performed. Subsequently, monoclonal gammopathy of undetermined significance (MGUS) associated with mediastinal amyloidosis was diagnosed. We hereby report a case in which EBUS-TBNA led to a successful diagnosis of amyloidosis. PMID:26862422

  12. Navigating actions through the rodent parietal cortex

    PubMed Central

    Whitlock, Jonathan R.

    2014-01-01

    The posterior parietal cortex (PPC) participates in a manifold of cognitive functions, including visual attention, working memory, spatial processing, and movement planning. Given the vast interconnectivity of PPC with sensory and motor areas, it is not surprising that neuronal recordings show that PPC often encodes mixtures of spatial information as well as the movements required to reach a goal. Recent work sought to discern the relative strength of spatial vs. motor signaling in PPC by recording single unit activity in PPC of freely behaving rats during selective changes in either the spatial layout of the local environment or in the pattern of locomotor behaviors executed during navigational tasks. The results revealed unequivocally a predominant sensitivity of PPC neurons to locomotor action structure, with subsets of cells even encoding upcoming movements more than 1 s in advance. In light of these and other recent findings in the field, I propose that one of the key contributions of PPC to navigation is the synthesis of goal-directed behavioral sequences, and that the rodent PPC may serve as an apt system to investigate cellular mechanisms for spatial motor planning as traditionally studied in humans and monkeys. PMID:24860475

  13. Treating Enlarged Prostate (BPH): Which Drugs Work Best

    MedlinePlus

    ... the prostate gets larger. This is called prostate enlargement, or BPH (benign prostatic hyperplasia). Why should I ... alpha-blocker doxazosin for a first treatment. Prostate enlargement affects millions of men, including about half of ...

  14. Novel carbocyle enlargement in aqueous medium

    SciTech Connect

    Li, C.J.; Chen, D.L.; Lu, Y.Q.; Haberman, J.X.; Mague, J.T.

    1996-05-01

    For two-atom ring expansions, the photochemical method of [2+2] cyclization-decyclization is the most successful. The [2+2] cycloaddition of an acetylenic ester to an enamine of a cyclic ketone and subsequent opening of the annulated cyclobutene moiety formed in another useful method for two-carbon ring expansion. We report here a novel two-atom carbocycle enlargement based on the indium-mediated Barbier-Grignard type reaction in water. 7 refs., 1 fig., 1 tab.

  15. Parietal damage impairs learning of a visuomotor tracking skill.

    PubMed

    Cavaco, Sara; Anderson, Steven W; Chen, Kuan-Hua; Teixeira-Pinto, Armando; Damasio, Hanna

    2015-12-01

    This study evaluated the consequences of damage to the parietal lobe for learning a visuomotor tracking skill. Thirty subjects with a single unilateral brain lesion (13 with and 17 without parietal damage) and 23 demographically comparable healthy subjects performed the Rotary Pursuit task. For each group, time on target increased significantly across the four learning blocks. Subjects with parietal lesions had smaller improvements on the Rotary Pursuit from the 1st to the 4th block than subjects with lesions in other brain areas and healthy comparison subjects. The improvements on task performance from the 1st to the 2nd and from the 1st to the 3rd learning blocks were similar between groups. The parietal lobe appears to play an important role in the acquisition of a new visuomotor tracking skill, in particular during a relatively late phase of learning. PMID:26536523

  16. Parietal damage impairs learning of a visuomotor tracking skill.

    PubMed

    Cavaco, Sara; Anderson, Steven W; Chen, Kuan-Hua; Teixeira-Pinto, Armando; Damasio, Hanna

    2015-12-01

    This study evaluated the consequences of damage to the parietal lobe for learning a visuomotor tracking skill. Thirty subjects with a single unilateral brain lesion (13 with and 17 without parietal damage) and 23 demographically comparable healthy subjects performed the Rotary Pursuit task. For each group, time on target increased significantly across the four learning blocks. Subjects with parietal lesions had smaller improvements on the Rotary Pursuit from the 1st to the 4th block than subjects with lesions in other brain areas and healthy comparison subjects. The improvements on task performance from the 1st to the 2nd and from the 1st to the 3rd learning blocks were similar between groups. The parietal lobe appears to play an important role in the acquisition of a new visuomotor tracking skill, in particular during a relatively late phase of learning.

  17. Parietal cortex and representation of the mental Self

    PubMed Central

    Lou, Hans C.; Luber, Bruce; Crupain, Michael; Keenan, Julian P.; Nowak, Markus; Kjaer, Troels W.; Sackeim, Harold A.; Lisanby, Sarah H.

    2004-01-01

    For a coherent and meaningful life, conscious self-representation is mandatory. Such explicit “autonoetic consciousness” is thought to emerge by retrieval of memory of personally experienced events (“episodic memory”). During episodic retrieval, functional imaging studies consistently show differential activity in medial prefrontal and medial parietal cortices. With positron-emission tomography, we here show that these medial regions are functionally connected and interact with lateral regions that are activated according to the degree of self-reference. During retrieval of previous judgments of Oneself, Best Friend, and the Danish Queen, activation increased in the left lateral temporal cortex and decreased in the right inferior parietal region with decreasing self-reference. Functionally, the former region was preferentially connected to medial prefrontal cortex, the latter to medial parietal. The medial parietal region may, then, be conceived of as a nodal structure in self-representation, functionally connected to both the right parietal and the medial prefrontal cortices. To determine whether medial parietal cortex in this network is essential for episodic memory retrieval with self-representation, we used transcranial magnetic stimulation over the region to transiently disturb neuronal circuitry. There was a decrease in the efficiency of retrieval of previous judgment of mental Self compared with retrieval of judgment of Other with transcranial magnetic stimulation at a latency of 160 ms, confirming the hypothesis. This network is strikingly similar to the network of the resting conscious state, suggesting that self-monitoring is a core function in resting consciousness. PMID:15096584

  18. Conductance enlargement in picoscale electroburnt graphene nanojunctions

    PubMed Central

    Sadeghi, Hatef; Mol, Jan A.; Lau, Chit Siong; Briggs, G. Andrew D.; Warner, Jamie; Lambert, Colin J.

    2015-01-01

    Provided the electrical properties of electroburnt graphene junctions can be understood and controlled, they have the potential to underpin the development of a wide range of future sub-10-nm electrical devices. We examine both theoretically and experimentally the electrical conductance of electroburnt graphene junctions at the last stages of nanogap formation. We account for the appearance of a counterintuitive increase in electrical conductance just before the gap forms. This is a manifestation of room-temperature quantum interference and arises from a combination of the semimetallic band structure of graphene and a cross-over from electrodes with multiple-path connectivity to single-path connectivity just before breaking. Therefore, our results suggest that conductance enlargement before junction rupture is a signal of the formation of electroburnt junctions, with a picoscale current path formed from a single sp2 bond. PMID:25730863

  19. Mechanisms of spatial attention control in frontal and parietal cortex.

    PubMed

    Szczepanski, Sara M; Konen, Christina S; Kastner, Sabine

    2010-01-01

    Theories of spatial attentional control have been largely based upon studies of patients suffering from visuospatial neglect, resulting from circumscribed lesions of frontal and posterior parietal cortex. In the intact brain, the control of spatial attention has been related to a distributed frontoparietal attention network. Little is known about the nature of the control mechanisms exerted by this network. Here, we used a novel region-of-interest approach to relate activations of the attention network to recently described topographic areas in frontal cortex [frontal eye field (FEF), PreCC/IFS (precentral cortex/inferior frontal sulcus)] and parietal cortex [intraparietal sulcus areas (IPS1-IPS5) and an area in the superior parietal lobule (SPL1)] to examine their spatial attention signals. We found that attention signals in most topographic areas were spatially specific, with stronger responses when attention was directed to the contralateral than to the ipsilateral visual field. Importantly, two hemispheric asymmetries were found. First, a region in only right, but not left SPL1 carried spatial attention signals. Second, left FEF and left posterior parietal cortex (IPS1/2) generated stronger contralateral biasing signals than their counterparts in the right hemisphere. These findings are the first to characterize spatial attention signals in topographic frontal and parietal cortex and provide a neural basis in support of an interhemispheric competition account of spatial attentional control. PMID:20053897

  20. [Microbiocenosis of parietal mucin in the gastrointestinal tract of rats].

    PubMed

    Vorob'ev, A A; Nesvizhskiĭ, Iu V; Bogdanova, E A; Korneev, L M

    2005-01-01

    The qualitative and quantitative composition of the microbial community in parietal mucin at different areas of the gastrointestinal tract (GIT) of rats was revealed. The pronounced variability in the quantitative and qualitative characteristics of microbiocenosis in parietal mucin of rats at different sections was revealed. The differences were most pronounced in the passage from upper to lower GIT sections, the large intestine found to be the richest biocenosis. The microbial composition of rat feces was faintly associated with the GIT parietal microbiocenosis. The individual areas of GIT mucosa were unique of their microbial characteristics and organization. This makes it possible to regard them as relatively independent biotopes and indicates that it is impossible to evaluate the microbial community by one of the colonic mucosal sifes. PMID:16438365

  1. FRONTAL AND PARIETAL CORTEX CONTRIBUTIONS TO ACTION MODIFICATION

    PubMed Central

    Mutha, Pratik K.; Stapp, Lee H.; Sainburg, Robert L.; Haaland, Kathleen Y.

    2014-01-01

    Successful achievement of task goals depends critically on the ability to adjust ongoing actions in response to environmental changes. The neural substrates underlying action modification have been a topic of great controversy: both, posterior parietal cortex and frontal regions, particularly prefrontal cortex have been previously identified as crucial in this regard, with most studies arguing in favor of one or the other. We aimed to address this controversy and understand whether frontal and parietal regions might play distinct roles during action modification. We tested ipsilesional arm performance of 27 stroke patients with focal lesions to frontal or parietal regions of the left or right cerebral hemisphere, and left or right arm performance of 18 healthy subjects on the classic double-step task in which a target is unpredictably displaced to a new location, requiring modification of the ongoing action. Only right hemisphere frontal lesions adversely impacted the timing of initiation of the modified response, while only left hemisphere parietal lesions impaired the accuracy of the modified action. Patients with right frontal lesions tended to complete the ongoing action to the initially displayed baseline target and initiated the new movement after a significant delay. In contrast, patients with left parietal damage did not accurately reach the new target location, but compared to the other groups, initiated the new action during an earlier phase of motion, before their baseline action was complete. Our findings thus suggest distinct, hemisphere specific contributions of frontal and parietal regions to action modification, and bring together, for the first time, disparate sets of prior findings about its underlying neural substrates. PMID:24763127

  2. Amygdalar enlargement associated with unique perception.

    PubMed

    Asari, Tomoki; Konishi, Seiki; Jimura, Koji; Chikazoe, Junichi; Nakamura, Noriko; Miyashita, Yasushi

    2010-01-01

    Interference by amygdalar activity in perceptual processes has been reported in many previous studies. Consistent with these reports, previous clinical studies have shown amygdalar volume change in multiple types of psychotic disease presenting with unusual perception. However, the relationship between variation in amygdalar volume in the normal population and the tendency toward unusual or unique perception has never been investigated. To address this issue, we defined an index to represent the tendency toward unique perception using ambiguous stimuli: subjects were instructed to state what the figures looked like to them, and "unique responses" were defined depending on the appearance frequency of the same responses in an age- and gender-matched control group. The index was defined as the ratio of unique responses to total responses per subject. We obtained structural brain images and values of the index from sixty-eight normal subjects. Voxel-based morphometry analyses revealed a positive correlation between amygdalar volume and the index. Since previous reports have indicated that unique responses were observed at higher frequency in the artistic population than in the nonartistic normal population, this positive correlation suggests that amygdalar enlargement in the normal population might be related to creative mental activity.

  3. Enlarged cerebrospinal fluid spaces in infants with subdural hematomas

    SciTech Connect

    Kapila, A.; Trice, J.; Spies, W.G.; Siegel, B.A.; Gado, M.H.

    1982-03-01

    Computed tomography in 16 infants with subdural hematomas showed enlarged basal cisterns, a wide interhemispheric fissure, prominent cortical sulci, and varying degrees of ventricular enlargement. Radionuclide cisternography in eight of the 16 patients showed findings consistent with enlargement of the subarachnoid space rather than those of communicating hydrocephalus. Clinical findings and brief follow-up showed no convincing evidence for cerebral atrophy in 13 patients. These findings suggest that the enlarged subarachnoid space, which is encountered in some infants and may be a developmental variant, predisposes such infants to subdural hematomas.

  4. Impairments in Tactile Search Following Superior Parietal Damage

    ERIC Educational Resources Information Center

    Skakoon-Sparling, Shayna P.; Vasquez, Brandon P.; Hano, Kate; Danckert, James

    2011-01-01

    The superior parietal cortex is critical for the control of visually guided actions. Research suggests that visual stimuli relevant to actions are preferentially processed when they are in peripersonal space. One recent study demonstrated that visually guided movements towards the body were more impaired in a patient with damage to superior…

  5. Parietal cortex mediates perceptual Gestalt grouping independent of stimulus size.

    PubMed

    Grassi, Pablo R; Zaretskaya, Natalia; Bartels, Andreas

    2016-06-01

    The integration of local moving elements into a unified gestalt percept has previously been linked to the posterior parietal cortex. There are two possible interpretations for the lack of involvement of other occipital regions. The first is that parietal cortex is indeed uniquely functionally specialized to perform grouping. Another possibility is that other visual regions can perform grouping as well, but that the large spatial separation of the local elements used previously exceeded their neurons' receptive field (RF) sizes, preventing their involvement. In this study we distinguished between these two alternatives. We measured whole-brain activity using fMRI in response to a bistable motion illusion that induced mutually exclusive percepts of either an illusory global Gestalt or of local elements. The stimulus was presented in two sizes, a large version known to activate IPS only, and a version sufficiently small to fit into the RFs of mid-level dorsal regions such as V5/MT. We found that none of the separately localized motion regions apart from parietal cortex showed a preference for global Gestalt perception, even for the smaller version of the stimulus. This outcome suggests that grouping-by-motion is mediated by a specialized size-invariant mechanism with parietal cortex as its anatomical substrate.

  6. Human posterior parietal cortex mediates hand-specific planning

    PubMed Central

    Valyear, Kenneth F.; Frey, Scott H.

    2015-01-01

    The processes underlying action planning are fundamental to adaptive behavior and can be influenced by recent motor experience. Here, we used a novel fMRI Repetition Suppression (RS) design to test the hypotheses that action planning unfolds more efficiently for successive actions made with the same hand. More efficient processing was predicted to correspond with both faster response times (RTs) to initiate actions and reduced fMRI activity levels – RS. Consistent with these predictions, we detected faster RTs for actions made with the same hand and accompanying fMRI-RS within bilateral posterior parietal cortex and right-lateralized parietal operculum. Within posterior parietal cortex, these RS effects were localized to intraparietal and superior parietal cortices. These same areas were more strongly activated for actions involving the contralateral hand. The findings provide compelling new evidence for the specification of action plans in hand-specific terms, and indicate that these processes are sensitive to recent motor history. Consistent with computational efficiency accounts of motor history effects, the findings are interpreted as evidence for comparatively more efficient processing underlying action planning when successive actions involve the same versus opposite hand. PMID:25842294

  7. Parietal network underlying movement control: disturbances during subcortical electrostimulation.

    PubMed

    Almairac, Fabien; Herbet, Guillaume; Moritz-Gasser, Sylvie; Duffau, Hugues

    2014-07-01

    Our understanding of brain movement control has changed over the last two decades. Recent findings in the monkey and in humans have led to a parallel and interconnected network. Nevertheless, little is known about these networks. Here, we present two cases of patients with a parietal low-grade glioma. They underwent surgery under local anesthesia with cortical and subcortical mapping. For patient 1, subcortical electrostimulation immediately posterior to thalamocortical fibers induced movement disorders, with an inhibition of leg and arm movements medially and, more laterally, an acceleration of arm movement. For patient 2, electrostimulation of white matter immediately posterior to thalamocortical fibers induced an inhibition of both arm movement. It means that the detected fibers in the parietal lobe may be involved in the motor control modulation. They are distributed veil-like immediately posterior to thalamocortical pathways and could correspond to a fronto-parietal movement control subnetwork. These two cases highlight the major role of the subcortical connectivity in movement regulation, involving parietal lobe, thus the necessity to be identified and preserved during brain surgery.

  8. Left inferior parietal lobe engagement in social cognition and language.

    PubMed

    Bzdok, Danilo; Hartwigsen, Gesa; Reid, Andrew; Laird, Angela R; Fox, Peter T; Eickhoff, Simon B

    2016-09-01

    Social cognition and language are two core features of the human species. Despite distributed recruitment of brain regions in each mental capacity, the left parietal lobe (LPL) represents a zone of topographical convergence. The present study quantitatively summarizes hundreds of neuroimaging studies on social cognition and language. Using connectivity-based parcellation on a meta-analytically defined volume of interest (VOI), regional coactivation patterns within this VOI allowed identifying distinct subregions. Across parcellation solutions, two clusters emerged consistently in rostro-ventral and caudo-ventral aspects of the parietal VOI. Both clusters were functionally significantly associated with social-cognitive and language processing. In particular, the rostro-ventral cluster was associated with lower-level processing facets, while the caudo-ventral cluster was associated with higher-level processing facets in both mental capacities. Contrarily, in the (less stable) dorsal parietal VOI, all clusters reflected computation of general-purpose processes, such as working memory and matching tasks, that are frequently co-recruited by social or language processes. Our results hence favour a rostro-caudal distinction of lower- versus higher-level processes underlying social cognition and language in the left inferior parietal lobe. PMID:27241201

  9. Neuro-ophthalmological complications of enlargement of the third ventricle.

    PubMed Central

    Osher, R. H.; Corbett, J. J.; Schatz, N. J.; Savino, P. J.; Orr, L. S.

    1978-01-01

    A wide variety of visual sensory and ocular motor problems may occur as a direct result of enlargement of the third ventricle. Four patients are described with optic nerve dysfunction, partial third nerve palsy, proptosis, and Sylvian aqueduct syndrome all resulting from an enlarged third ventricle. The pathogenetic mechanisms are discussed. Images PMID:687551

  10. Functional connectivity of parietal cortex during temporal selective attention.

    PubMed

    Tyler, Sarah C; Dasgupta, Samhita; Agosta, Sara; Battelli, Lorella; Grossman, Emily D

    2015-04-01

    Perception of natural experiences requires allocation of attention towards features, objects, and events that are moving and changing over time. This allocation of attention is controlled by large-scale brain networks that, when damaged, cause widespread cognitive deficits. In particular, damage to ventral parietal cortex (right lateralized TPJ, STS, supramarginal and angular gyri) is associated with failures to selectively attend to and isolate features embedded within rapidly changing visual sequences (Battelli, Pascual-Leone, & Cavanagh, 2007; Husain, Shapiro, Martin, & Kennard, 1997). In this study, we used fMRI to investigate the neural activity and functional connectivity of intact parietal cortex while typical subjects judged the relative onsets and offsets of rapidly flickering tokens (a phase discrimination task in which right parietal patients are impaired). We found two regions in parietal cortex correlated with task performance: a bilateral posterior TPJ (pTPJ) and an anterior right-lateralized TPJ (R aTPJ). Both regions were deactivated when subjects engaged in the task but showed different patterns of functional connectivity. The bilateral pTPJ was strongly connected to nodes within the default mode network (DMN) and the R aTPJ was connected to the attention network. Accurate phase discriminations were associated with increased functional correlations between sensory cortex (hMT+) and the bilateral pTPJ, whereas accuracy on a control task was associated with yoked activity in the hMT+ and the R aTPJ. We conclude that temporal selective attention is particularly sensitive for revealing information pathways between sensory and core cognitive control networks that, when damaged, can lead to nonspatial attention impairments in right parietal stroke patients. PMID:25747530

  11. A rare chronic constrictive pericarditis with localized adherent visceral pericardium and normal parietal pericardium: a case report.

    PubMed

    Ni, Qingqiang; Yun, Lin; Xu, Rui; Li, Guohua; Yao, Yucai; Li, Jiamin

    2016-09-01

    Classic constrictive pericarditis (CP) is characterized by fibrous scarring and adhesion of both the visceral pericardium and the parietal pericardium, which leads to restricted cardiac filling. However, diagnosing CP with normal thickness pericardium and without calcification is still a challenge. The predominant cause in the developed world is idiopathic or viral pericarditis followed by post-cardiac surgery and post-radiation. Tuberculosis still remains a common cause of CP in developing countries. In this report, we describe a rare case of idiopathic localized constrictive visceral pericardium with normal thickness of the parietal pericardium in a middle-aged man. The patient presented with unexplained right heart failure and echocardiography showed moderate bi-atrial enlargement which should be identified with the restrictive cardiomyopathy. After 10 months of conservative treatment, the progression of right heart failure was remaining. A pericardiectomy was performed and the patient recovered. This case serves as a reminder to consider CP in patients with unexplained right heart failure, so that timely investigation and treatment can be initiated. PMID:27527362

  12. Chest radiographs fail to detect right ventricular enlargement and right atrial enlargement in patients with a pure restrictive ventilatory impairment.

    PubMed

    Shivkumar, K; Ravi, K; Henry, J W; Eichenhorn, M S; Stein, P D

    1994-08-01

    The validity of measurements of the cardiac silhouette on chest radiographs for the evaluation of right ventricular enlargement and right atrial enlargement in patients with a pure restrictive ventilatory impairment was investigated in 19 patients. The forced vital capacity (FVC) percent predicted in these patients was 59 +/- 12 percent (mean +/- SD) (range, 29 to 79 percent). Right ventricular enlargement, by two-dimensional echocardiography, was defined as a right ventricular area > 20.4 cm2 and right atrial enlargement was defined as a right atrial area > 15.3 cm2. Chest radiographic measurements in the posteroanterior (PA) projection included distance from the midline to the farthest point of the right border of the cardiac silhouette, transverse cardiac diameter, and cardiothoracic ratio. Measurements in the lateral projection included the lateral horizontal transverse diameter, ventral portion of the lateral broad diameter, and obliteration of the retrosternal space. Neither the right ventricular area nor the right atrial area correlated with any of these radiographic measurements. There were no differences in these chest radiographic measurements among patients with normal right ventricular and right atrial dimensions, patients with right ventricular enlargement, and patients with right atrial enlargement. We conclude, therefore, that PA and lateral chest radiographs do not reliably detect right ventricular enlargement or right atrial enlargement in patients with a pure restrictive ventilatory impairment.

  13. Prefrontal-parietal function: from foraging to foresight.

    PubMed

    Genovesio, Aldo; Wise, Steven P; Passingham, Richard E

    2014-02-01

    Comparative neuroanatomy shows that new prefrontal areas emerged during the evolution of anthropoid primates to augment prefrontal, parietal, and temporal areas that had evolved in earlier primates. We recently proposed that the new anthropoid areas reduce foraging errors by generating goals from current contexts and learning to do so rapidly, sometimes based on single events. Among the contexts used to generate these goals, the posterior parietal cortex provides the new prefrontal areas with information about relational metrics such as order, number, duration, length, distance and proportion, which play a crucial role in foraging choices. Here we propose that this specialized network later became adapted to support the human capacity for reasoning and general problem-solving.

  14. Overlapping Parietal Activity in Memory and Perception: Evidence for the Attention to Memory Model

    ERIC Educational Resources Information Center

    Cabeza, Roberto; Mazuz, Yonatan S.; Stokes, Jared; Kragel, James E.; Woldorff, Marty G.; Ciaramelli, Elisa; Olson, Ingrid R.; Moscovitch, Morris

    2011-01-01

    The specific role of different parietal regions to episodic retrieval is a topic of intense debate. According to the Attention to Memory (AtoM) model, dorsal parietal cortex (DPC) mediates top-down attention processes guided by retrieval goals, whereas ventral parietal cortex (VPC) mediates bottom-up attention processes captured by the retrieval…

  15. Dissociation of Subtraction and Multiplication in the Right Parietal Cortex: Evidence from Intraoperative Cortical Electrostimulation

    ERIC Educational Resources Information Center

    Yu, Xiaodan; Chen, Chuansheng; Pu, Song; Wu, Chenxing; Li, Yongnian; Jiang, Tao; Zhou, Xinlin

    2011-01-01

    Previous research has consistently shown that the left parietal cortex is critical for numerical processing, but the role of the right parietal lobe has been much less clear. This study used the intraoperative cortical electrical stimulation approach to investigate neural dissociation in the right parietal cortex for subtraction and…

  16. Impairments in tactile search following superior parietal damage.

    PubMed

    Skakoon-Sparling, Shayna P; Vasquez, Brandon P; Hano, Kate; Danckert, James

    2011-08-01

    The superior parietal cortex is critical for the control of visually guided actions. Research suggests that visual stimuli relevant to actions are preferentially processed when they are in peripersonal space. One recent study demonstrated that visually guided movements towards the body were more impaired in a patient with damage to superior parietal cortex. Whereas past studies have explored disordered movement in optic ataxic patients, there has been less exploration of space perception in terms of search capacity in this population. In addition, there is some debate concerning the relationship between deficits of visuomotor control and impaired attention/perception in optic ataxia. Given that the dorsal stream has been implicated in the spatial processing of stimuli in peripersonal space, and damage to this region is known to cause optic ataxia, we felt that further investigation was warranted. We examined tactile search behavior in the fronto-parallel and radial planes in a patient with right superior parietal damage and optic ataxia. We used a pegboard with removable cylindrical pegs that allowed for the reorganization of targets between trials. To better characterize three-dimensional search behavior, we included both horizontal and vertical search conditions. Results showed that the patient spent more time searching, was more accurate and revisited more targets in right versus left space. Interestingly, the patient spent the majority of her time specifically searching the lower right quadrant of the stimulus array. Further analysis revealed lower target detection rates along the outer borders of the pegboard on all sides. The search pattern observed here is unusual considering that all targets were within arm's reach. The present experiment demonstrates that damage to superior parietal cortex impairs tactile search and biases exploration towards lower right peripersonal space.

  17. Neuronal oscillations form parietal/frontal networks during contour integration.

    PubMed

    Castellano, Marta; Plöchl, Michael; Vicente, Raul; Pipa, Gordon

    2014-01-01

    The ability to integrate visual features into a global coherent percept that can be further categorized and manipulated are fundamental abilities of the neural system. While the processing of visual information involves activation of early visual cortices, the recruitment of parietal and frontal cortices has been shown to be crucial for perceptual processes. Yet is it not clear how both cortical and long-range oscillatory activity leads to the integration of visual features into a coherent percept. Here, we will investigate perceptual grouping through the analysis of a contour categorization task, where the local elements that form contour must be linked into a coherent structure, which is then further processed and manipulated to perform the categorization task. The contour formation in our visual stimulus is a dynamic process where, for the first time, visual perception of contours is disentangled from the onset of visual stimulation or from motor preparation, cognitive processes that until now have been behaviorally attached to perceptual processes. Our main finding is that, while local and long-range synchronization at several frequencies seem to be an ongoing phenomena, categorization of a contour could only be predicted through local oscillatory activity within parietal/frontal sources, which in turn, would synchronize at gamma (>30 Hz) frequency. Simultaneously, fronto-parietal beta (13-30 Hz) phase locking forms a network spanning across neural sources that are not category specific. Both long range networks, i.e., the gamma network that is category specific, and the beta network that is not category specific, are functionally distinct but spatially overlapping. Altogether, we show that a critical mechanism underlying contour categorization involves oscillatory activity within parietal/frontal cortices, as well as its synchronization across distal cortical sites.

  18. Neuronal oscillations form parietal/frontal networks during contour integration.

    PubMed

    Castellano, Marta; Plöchl, Michael; Vicente, Raul; Pipa, Gordon

    2014-01-01

    The ability to integrate visual features into a global coherent percept that can be further categorized and manipulated are fundamental abilities of the neural system. While the processing of visual information involves activation of early visual cortices, the recruitment of parietal and frontal cortices has been shown to be crucial for perceptual processes. Yet is it not clear how both cortical and long-range oscillatory activity leads to the integration of visual features into a coherent percept. Here, we will investigate perceptual grouping through the analysis of a contour categorization task, where the local elements that form contour must be linked into a coherent structure, which is then further processed and manipulated to perform the categorization task. The contour formation in our visual stimulus is a dynamic process where, for the first time, visual perception of contours is disentangled from the onset of visual stimulation or from motor preparation, cognitive processes that until now have been behaviorally attached to perceptual processes. Our main finding is that, while local and long-range synchronization at several frequencies seem to be an ongoing phenomena, categorization of a contour could only be predicted through local oscillatory activity within parietal/frontal sources, which in turn, would synchronize at gamma (>30 Hz) frequency. Simultaneously, fronto-parietal beta (13-30 Hz) phase locking forms a network spanning across neural sources that are not category specific. Both long range networks, i.e., the gamma network that is category specific, and the beta network that is not category specific, are functionally distinct but spatially overlapping. Altogether, we show that a critical mechanism underlying contour categorization involves oscillatory activity within parietal/frontal cortices, as well as its synchronization across distal cortical sites. PMID:25165437

  19. Neuronal oscillations form parietal/frontal networks during contour integration

    PubMed Central

    Castellano, Marta; Plöchl, Michael; Vicente, Raul; Pipa, Gordon

    2014-01-01

    The ability to integrate visual features into a global coherent percept that can be further categorized and manipulated are fundamental abilities of the neural system. While the processing of visual information involves activation of early visual cortices, the recruitment of parietal and frontal cortices has been shown to be crucial for perceptual processes. Yet is it not clear how both cortical and long-range oscillatory activity leads to the integration of visual features into a coherent percept. Here, we will investigate perceptual grouping through the analysis of a contour categorization task, where the local elements that form contour must be linked into a coherent structure, which is then further processed and manipulated to perform the categorization task. The contour formation in our visual stimulus is a dynamic process where, for the first time, visual perception of contours is disentangled from the onset of visual stimulation or from motor preparation, cognitive processes that until now have been behaviorally attached to perceptual processes. Our main finding is that, while local and long-range synchronization at several frequencies seem to be an ongoing phenomena, categorization of a contour could only be predicted through local oscillatory activity within parietal/frontal sources, which in turn, would synchronize at gamma (>30 Hz) frequency. Simultaneously, fronto-parietal beta (13–30 Hz) phase locking forms a network spanning across neural sources that are not category specific. Both long range networks, i.e., the gamma network that is category specific, and the beta network that is not category specific, are functionally distinct but spatially overlapping. Altogether, we show that a critical mechanism underlying contour categorization involves oscillatory activity within parietal/frontal cortices, as well as its synchronization across distal cortical sites. PMID:25165437

  20. [A cytoprotective chloride channel in gastric parietal cells].

    PubMed

    Sakai, H

    1999-08-01

    This review summarizes the regulatory mechanisms and physiological functions of the novel sub-pS Cl- channel (0.3 pS) that is present abundantly in the basolateral membrane of rabbit gastric parietal cells. The sub-pS Cl- channel is voltage-independent and inhibited by NPPB, a Cl- channel blocker. We found that this gastric Cl- channel is linked to three important physiological roles. First, the sub-pS Cl- channel has a housekeeping role through dominating the cell membrane potential. Although several types of cation channels are present, they do not significantly contribute to the membrane potential in the parietal cells. Second, the Cl- channel is activated by prostaglandin E2 via the EP3 receptor/Ca2-/nitric oxide (NO)/cGMP pathway. A vasodilator ecabapide also activates the channel by increasing the intracellular cGMP content. The NO/cGMP pathway-mediated opening of the sub-pS Cl- channel is essential for cytoprotection against ethanol-induced damage in the gastric parietal cells. The NO/cGMP-elicited cytoprotection is abolished by NPPB. To our knowledge, this Cl- channel is the first identified target for the cytoprotective NO/cGMP pathway. Third, the sub-pS Cl- channel is inhibited by the GTP-binding protein-mediated intracellular production of superoxide anion. Hydrogen peroxide and hydroxyl radicals have no effect on the channel activity. The intracellular superoxide anion acts as a messenger in the negative regulatory mechanism of the sub-pS Cl- channel. The similar sub-pS Cl- channel is also found in rat gastric parietal cells.

  1. [The endocranial parietal vascular traces in the hominid line].

    PubMed

    Saban, R

    1977-03-01

    The study of the grooves traced by the middle meningeal veins on the parietal bone or the endocast of Hominid fossils shows different patterns which correspond to each evolutive stage. Height types are characterised among the Hominids (Australopithecines, Archanthropines, Paleanthropines and Neanthropines): I, robust Australopithecine type; II, gracile Australopithecine type; III, earliest Pithecanthropine type; IV, evolved Pithecanthropine type; V, Preneandertal type; VI, neandertal type; VII, Neanthropine type; VIII, modern type. PMID:405108

  2. Gestalt perception is associated with reduced parietal beta oscillations.

    PubMed

    Zaretskaya, Natalia; Bartels, Andreas

    2015-05-15

    The ability to perceive composite objects as a whole is fundamental for visual perception in a complex and cluttered natural environment. This ability may be mediated by increased communication between neural representations of distinct object elements, and has been linked to increased synchronization of oscillatory brain activity in the gamma band. Previous studies of perceptual grouping either guided attention between local and global aspects of a given stimulus or manipulated its physical properties to achieve grouped and ungrouped perceptual conditions. In contrast to those studies, we fully matched the physical properties underlying global and local percepts using a bistable stimulus that causes the viewer to perceive either local motion of multiple elements or global motion of two illusory shapes without any external change. To test the synchronization hypothesis we recorded brain activity with EEG, while human participants viewed the stimulus and reported changes in their perception. In contrast to previous findings we show that power of the beta-band was lower during perception of global Gestalt than during that of local elements. Source localization places these differences in the posterior parietal cortex, overlapping with a site previously associated with both attention and Gestalt perception. These findings reveal a role of parietal beta-band activity in internally, rather than externally or attention-driven processes of Gestalt perception. They also add to the growing evidence for shared neural substrates of attention and Gestalt perception, both being linked to parietal cortex.

  3. Bottom-up Visual Integration in the Medial Parietal Lobe.

    PubMed

    Pflugshaupt, Tobias; Nösberger, Myriam; Gutbrod, Klemens; Weber, Konrad P; Linnebank, Michael; Brugger, Peter

    2016-03-01

    Largely based on findings from functional neuroimaging studies, the medial parietal lobe is known to contribute to internally directed cognitive processes such as visual imagery or episodic memory. Here, we present 2 patients with behavioral impairments that extend this view. Both had chronic unilateral lesions of nearly the entire medial parietal lobe, but in opposite hemispheres. Routine neuropsychological examination conducted >4 years after the onset of brain damage showed little deficits of minor severity. In contrast, both patients reported persistent unusual visual impairment. A comprehensive series of tachistoscopic experiments with lateralized stimulus presentation and comparison with healthy participants revealed partial visual hemiagnosia for stimuli presented to their contralesional hemifield, applying inferential single-case statistics to evaluate deficits and dissociations. Double dissociations were found in 4 experiments during which participants had to integrate more than one visual element, either through comparison or formation of a global gestalt. Against the background of recent neuroimaging findings, we conclude that of all medial parietal structures, the precuneus is the most likely candidate for a crucial involvement in such bottom-up visual integration.

  4. Early recurrence and ongoing parietal driving during elementary visual processing

    PubMed Central

    Plomp, Gijs; Hervais-Adelman, Alexis; Astolfi, Laura; Michel, Christoph M.

    2015-01-01

    Visual stimuli quickly activate a broad network of brain areas that often show reciprocal structural connections between them. Activity at short latencies (<100 ms) is thought to represent a feed-forward activation of widespread cortical areas, but fast activation combined with reciprocal connectivity between areas in principle allows for two-way, recurrent interactions to occur at short latencies after stimulus onset. Here we combined EEG source-imaging and Granger-causal modeling with high temporal resolution to investigate whether recurrent and top-down interactions between visual and attentional brain areas can be identified and distinguished at short latencies in humans. We investigated the directed interactions between widespread occipital, parietal and frontal areas that we localized within participants using fMRI. The connectivity results showed two-way interactions between area MT and V1 already at short latencies. In addition, the results suggested a large role for lateral parietal cortex in coordinating visual activity that may be understood as an ongoing top-down allocation of attentional resources. Our results support the notion that indirect pathways allow early, evoked driving from MT to V1 to highlight spatial locations of motion transients, while influence from parietal areas is continuously exerted around stimulus onset, presumably reflecting task-related attentional processes. PMID:26692466

  5. 2. Historic American Buildings Survey L. D. Andrew, Photographer enlarged ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey L. D. Andrew, Photographer enlarged Photographed by Harold Bush-Brown Dec. 17, 1936 PORTION OF FRONT - Griffin-Mott House, Mott Street & Front Avenue, Columbus, Muscogee County, GA

  6. 2. Historic American Buildings Survey L. D. Andrew, Photographer Enlarged ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey L. D. Andrew, Photographer Enlarged Photo From photo of Miss Edith Johnston, Savannah, Ga. 1936 VIEW OF FRONT AND RIGHT SIDE (Restoration 1936) - Wild Heron Plantation, Little Ogeechee River Vicinity, Savannah, Chatham County, GA

  7. 1. Historic American Buildings Survey L. D. Andrew, Photographer Enlarged ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey L. D. Andrew, Photographer Enlarged Photo From Photo of Miss Edith Johnston's, Savannah, Ga. 1936 VIEW OF FRONT AND SIDE (Before Restoration, 1936). - Wild Heron Plantation, Little Ogeechee River Vicinity, Savannah, Chatham County, GA

  8. How do plants enlarge? A balancing act; Final report

    SciTech Connect

    Boyer, J.S.

    1996-12-31

    Cells of plants are surrounded by strong walls that prevent rupture from internal pressures that can be two or three times that of an automobile tire. In this way, the walls protect the cytoplasm. However, at the same time, the cells can enlarge as they grow. How this balancing act works and how it enlarges the plant were the subject of a recent conference at the University of Delaware in Lewes. The aim was to identify areas for future research that could explain the enlargement of whole plants. There is a large practical need to predict and modify plant enlargement but the additional processes that overlie the molecular ones need to be integrated with the molecular information before a picture will emerge. How best to accomplish this involved input from cross-disciplinary areas in biomechanics, physics and engineering as well as molecular biology, biochemistry and ultrastructure.

  9. 9. (5 X 7 enlargement from 4 X 5 negative) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. (5 X 7 enlargement from 4 X 5 negative) FIRST FLOOR, WINDOW MOLDING ON SOUTH WALL LOOKING SOUTH - Sites Homestead, Monongahela National Forest (Tract 390) East of Route 28, Seneca Rocks, Pendleton County, WV

  10. 2. Historic American Buildings Survey L. D. Andrew, Photographer, Enlarged ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey L. D. Andrew, Photographer, Enlarged Photographed by Harold Bush-Brown Nov. 14, 1936 VIEW OF EASTERN SLAVE CABIN - Bass Place (Slave Cabins), Columbus, Muscogee County, GA

  11. 1. Historic American Buildings Survey L. D. Andrew, Photographer Enlarged ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey L. D. Andrew, Photographer Enlarged Photographed by Harold Bush-Brown Nov. 14, 1936 GENERAL VIEW OF SLAVE CABINS - Bass Place (Slave Cabins), Columbus, Muscogee County, GA

  12. 1. Historic American Buildings Survey L. D. Andrew, Photographer (Enlarged ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey L. D. Andrew, Photographer (Enlarged by) Aug. 6, 1936 Photographed by Harold Bush-Brown SIDE VIEW - Covered Bridge, Spanning Soap Creek, Atlanta, Fulton County, GA

  13. Enlarged hands and feet – Not always acromegaly

    PubMed Central

    Ghatnatti, Vikrant; Sarma, Dipti; Saikia, Uma

    2012-01-01

    Pachydermoperiostosis maybe mistaken for acromegaly as it can present with progressive enlargement of hands and feet. We describe a 32 year old male with enlargement of hands and feet and extensive keloid formation. Family history was positive for similar complaints. X ray imaging showed normal heel pad thickness with acroosteolysis and subperiosteal new bone formation in hands and feet. IGF-1 was normal and glucose suppressed GH values were normal. PMID:23565412

  14. Scene-Selectivity and Retinotopy in Medial Parietal Cortex

    PubMed Central

    Silson, Edward H.; Steel, Adam D.; Baker, Chris I.

    2016-01-01

    Functional imaging studies in human reliably identify a trio of scene-selective regions, one on each of the lateral [occipital place area (OPA)], ventral [parahippocampal place area (PPA)], and medial [retrosplenial complex (RSC)] cortical surfaces. Recently, we demonstrated differential retinotopic biases for the contralateral lower and upper visual fields within OPA and PPA, respectively. Here, using functional magnetic resonance imaging, we combine detailed mapping of both population receptive fields (pRF) and category-selectivity, with independently acquired resting-state functional connectivity analyses, to examine scene and retinotopic processing within medial parietal cortex. We identified a medial scene-selective region, which was contained largely within the posterior and ventral bank of the parieto-occipital sulcus (POS). While this region is typically referred to as RSC, the spatial extent of our scene-selective region typically did not extend into retrosplenial cortex, and thus we adopt the term medial place area (MPA) to refer to this visually defined scene-selective region. Intriguingly MPA co-localized with a region identified solely on the basis of retinotopic sensitivity using pRF analyses. We found that MPA demonstrates a significant contralateral visual field bias, coupled with large pRF sizes. Unlike OPA and PPA, MPA did not show a consistent bias to a single visual quadrant. MPA also co-localized with a region identified by strong differential functional connectivity with PPA and the human face-selective fusiform face area (FFA), commensurate with its functional selectivity. Functional connectivity with OPA was much weaker than with PPA, and similar to that with face-selective occipital face area (OFA), suggesting a closer link with ventral than lateral cortex. Consistent with prior research, we also observed differential functional connectivity in medial parietal cortex for anterior over posterior PPA, as well as a region on the lateral

  15. Scene-Selectivity and Retinotopy in Medial Parietal Cortex.

    PubMed

    Silson, Edward H; Steel, Adam D; Baker, Chris I

    2016-01-01

    Functional imaging studies in human reliably identify a trio of scene-selective regions, one on each of the lateral [occipital place area (OPA)], ventral [parahippocampal place area (PPA)], and medial [retrosplenial complex (RSC)] cortical surfaces. Recently, we demonstrated differential retinotopic biases for the contralateral lower and upper visual fields within OPA and PPA, respectively. Here, using functional magnetic resonance imaging, we combine detailed mapping of both population receptive fields (pRF) and category-selectivity, with independently acquired resting-state functional connectivity analyses, to examine scene and retinotopic processing within medial parietal cortex. We identified a medial scene-selective region, which was contained largely within the posterior and ventral bank of the parieto-occipital sulcus (POS). While this region is typically referred to as RSC, the spatial extent of our scene-selective region typically did not extend into retrosplenial cortex, and thus we adopt the term medial place area (MPA) to refer to this visually defined scene-selective region. Intriguingly MPA co-localized with a region identified solely on the basis of retinotopic sensitivity using pRF analyses. We found that MPA demonstrates a significant contralateral visual field bias, coupled with large pRF sizes. Unlike OPA and PPA, MPA did not show a consistent bias to a single visual quadrant. MPA also co-localized with a region identified by strong differential functional connectivity with PPA and the human face-selective fusiform face area (FFA), commensurate with its functional selectivity. Functional connectivity with OPA was much weaker than with PPA, and similar to that with face-selective occipital face area (OFA), suggesting a closer link with ventral than lateral cortex. Consistent with prior research, we also observed differential functional connectivity in medial parietal cortex for anterior over posterior PPA, as well as a region on the lateral

  16. Gingival enlargements: Differential diagnosis and review of literature

    PubMed Central

    Agrawal, Amit Arvind

    2015-01-01

    Gingival enlargement is one of the frequent features of gingival diseases. However due to their varied presentations, the diagnosis of these entities becomes challenging for the clinician. They can be categorized based on their etiopathogenesis, location, size, extent, etc. Based on the existing knowledge and clinical experience, a differential diagnosis can be formulated. Subsequently, after detailed investigation, clinician makes a final diagnosis or diagnosis of exclusion. A perfect diagnosis is critically important, since the management of these lesions and prevention of their recurrence is completely dependent on it. Furthermore, in some cases where gingival enlargement could be the primary sign of potentially lethal systemic diseases, a correct diagnosis of these enlargements could prove life saving for the patient or at least initiate early treatment and improve the quality of life. The purpose of this review article is to highlight significant findings of different types of gingival enlargement which would help clinician to differentiate between them. A detailed decision tree is also designed for the practitioners, which will help them arrive at a diagnosis in a systematic manner. There still could be some lesions which may present in an unusual manner and make the diagnosis challenging. By knowing the existence of common and rare presentations of gingival enlargement, one can keep a broad view when formulating a differential diagnosis of localized (isolated, discrete, regional) or generalized gingival enlargement. PMID:26380825

  17. Gingival enlargements: Differential diagnosis and review of literature.

    PubMed

    Agrawal, Amit Arvind

    2015-09-16

    Gingival enlargement is one of the frequent features of gingival diseases. However due to their varied presentations, the diagnosis of these entities becomes challenging for the clinician. They can be categorized based on their etiopathogenesis, location, size, extent, etc. Based on the existing knowledge and clinical experience, a differential diagnosis can be formulated. Subsequently, after detailed investigation, clinician makes a final diagnosis or diagnosis of exclusion. A perfect diagnosis is critically important, since the management of these lesions and prevention of their recurrence is completely dependent on it. Furthermore, in some cases where gingival enlargement could be the primary sign of potentially lethal systemic diseases, a correct diagnosis of these enlargements could prove life saving for the patient or at least initiate early treatment and improve the quality of life. The purpose of this review article is to highlight significant findings of different types of gingival enlargement which would help clinician to differentiate between them. A detailed decision tree is also designed for the practitioners, which will help them arrive at a diagnosis in a systematic manner. There still could be some lesions which may present in an unusual manner and make the diagnosis challenging. By knowing the existence of common and rare presentations of gingival enlargement, one can keep a broad view when formulating a differential diagnosis of localized (isolated, discrete, regional) or generalized gingival enlargement.

  18. Prevalence of gingival enlargement in Karnataka school going children

    PubMed Central

    Krishna, K Bala; Raju, P Krishnam; Chitturi, Radha Raani; Smitha, G; Vijai, S; Srinivas, B V V

    2014-01-01

    Background: Periodontal diseases affect more people all over the world than dental caries. Increase in size of gingiva is known as gingival hyperplasia or gingival enlargement. Gingival swelling is almost universally the result of Fluid accumulation within the tissues. Enlargement and even aesthetically disfiguring over growth of the gingival tissue, is also a common finding of leukemia, scurvy and subjects undergoing the hormonal changes of puberty, pregnancy, menopause and drugs. Materials & Methods: A sample size of 1500 was taken. All children who were between the chronological age of 5-12 years from selected schools were included in the study.Three age groups were selected for the study, Group I: 5-7yrs, Group II: 7-9 yrs, Group III 9-12yrs. Each group comprised of 500 students. The examination of gingival enlargement was made according to Gingival Enlargement Index. The oral hygiene status of the child was examined using Oral Hygiene Index-Simplified. Results: The prevalence of Gingival Enlargement increased with the increase of age. Though the Prevalence of GE in female children (15.1%) was more than male children (13.4%), it was not statistically significant. Female children (1.6%) had a higher prevalence of epilepsy than male children (0.29%) in this present study. Conclusion: The prevalence of gingival enlargement was predominantly inflammatory, showing that the oral hygiene status of the oral Children in Karnataka was far from satisfactory. Further studies need to be undertaken regarding the prevalence if GE in School going children. How to cite the article: Krishna KB, Raju PK, Chitturi RR, Smitha G, Vijai S, Srinivas BV. Prevalence of gingival enlargement in Karnataka school going children. J Int Oral Health 2014;6(1):106-10. PMID:24653613

  19. Topographic Organization for Delayed Saccades in Human Posterior Parietal Cortex

    PubMed Central

    Schluppeck, Denis; Glimcher, Paul; Heeger, David J.

    2008-01-01

    Posterior parietal cortex (PPC) is thought to play a critical role in decision making, sensory attention, motor intention, and/or working memory. Research on the PPC in non-human primates has focused on the lateral intraparietal area (LIP) in the intraparietal sulcus (IPS). Neurons in LIP respond after the onset of visual targets, just before saccades to those targets, and during the delay period in between. To study the function of posterior parietal cortex in humans, it will be crucial to have a routine and reliable method for localizing specific parietal areas in individual subjects. Here, we show that human PPC contains at least two topographically organized regions, which are candidates for the human homologue of LIP. We mapped the topographic organization of human PPC for delayed (memory guided) saccades using fMRI. Subjects were instructed to fixate centrally while a peripheral target was briefly presented. After a further 3-s delay, subjects made a saccade to the remembered target location followed by a saccade back to fixation and a 1-s inter-trial interval. Targets appeared at successive locations “around the clock” (same eccentricity, ≈30° angular steps), to produce a traveling wave of activity in areas that are topographically organized. PPC exhibited topographic organization for delayed saccades. We defined two areas in each hemisphere that contained topographic maps of the contralateral visual field. These two areas were immediately rostral to V7 as defined by standard retinotopic mapping. The two areas were separated from each other and from V7 by reversals in visual field orientation. However, we leave open the possibility that these two areas will be further subdivided in future studies. Our results demonstrate that topographic maps tile the cortex continuously from V1 well into PPC. PMID:15817644

  20. Syndecan-1 in the Mouse Parietal Peritoneum Microcirculation in Inflammation

    PubMed Central

    Kowalewska, Paulina M.; Patrick, Amanda L.; Fox-Robichaud, Alison E.

    2014-01-01

    Background The heparan sulfate proteoglycan syndecan-1 (CD138) was shown to regulate inflammatory responses by binding chemokines and cytokines and interacting with adhesion molecules, thereby modulating leukocyte trafficking to tissues. The objectives of this study were to examine the expression of syndecan-1 and its role in leukocyte recruitment and chemokine presentation in the microcirculation underlying the parietal peritoneum. Methods Wild-type BALB/c and syndecan-1 null mice were stimulated with an intraperitoneal injection of Staphylococcus aureus LTA, Escherichia coli LPS or TNFα and the microcirculation of the parietal peritoneum was examined by intravital microscopy after 4 hours. Fluorescence confocal microscopy was used to examine syndecan-1 expression in the peritoneal microcirculation using fluorescent antibodies. Blocking antibodies to adhesion molecules were used to examine the role of these molecules in leukocyte-endothelial cell interactions in response to LTA. To determine whether syndecan-1 co-localizes with chemokines in vivo, fluorescent antibodies to syndecan-1 were co-injected intravenously with anti-MIP-2 (CXCL2), anti-KC (CXCL1) or anti-MCP-1 (CCL2). Results and Conclusion Syndecan-1 was localized to the subendothelial region of peritoneal venules and the mesothelial layer. Leukocyte rolling was significantly decreased with LPS treatment while LTA and TNFα significantly increased leukocyte adhesion compared with saline control. Leukocyte-endothelial cell interactions were not different in syndecan-1 null mice. Antibody blockade of β2 integrin (CD18), ICAM-1 (CD54) and VCAM-1 (CD106) did not decrease leukocyte adhesion in response to LTA challenge while blockade of P-selectin (CD62P) abrogated leukocyte rolling. Lastly, MIP-2 expression in the peritoneal venules was not dependent on syndecan-1 in vivo. Our data suggest that syndecan-1 is expressed in the parietal peritoneum microvasculature but does not regulate leukocyte recruitment

  1. Neural activity in the parietal eye of a lizard.

    PubMed

    MILLER, W H; WOLBARSHT, M L

    1962-01-26

    Electrical signs of activity in response to illumination of the parietal eye of the American chameleon, Anolis carolinensis, have been investigated. The responses were of two types. Under conditions of direct-coupled amplification, with glass pipette electrodes recording extracellularly from the retinal surface, the response consisted of an increase in negativity maintained throughout prolonged illumination. With capacitance-coupled amplification and metal electrodes, brisk mass discharges of nerve impulses were detected at the onset and cessation of illumination. During illumination a less vigorous maintained discharge was observed.

  2. Environmental reduplication associated with right frontal and parietal lobe injury.

    PubMed Central

    Ruff, R L; Volpe, B T

    1981-01-01

    Four patients with environmental reduplication, a specific form of spatial disorientation and confabulation are described. The patients maintained that their hospital rooms were located in their homes. Each patients had evidence of right frontal or right parietal injury based upon computed tomography, neurosurgery, and neuropsychological testing. The factors associated with environmental reduplication were: impaired spatial perception and visual memory, inability of the patients to recognise the inconsistency between their believed location and their actual location, confusion soon after admission to hospital, and a strong desire to be at home. PMID:7264684

  3. Sylvian fissure and parietal anatomy in children with autism spectrum disorder.

    PubMed

    Knaus, Tracey A; Tager-Flusberg, Helen; Foundas, Anne L

    2012-01-01

    Autism spectrum disorder (ASD) is characterized by deficits in social functioning and language and communication, with restricted interests or stereotyped behaviors. Anatomical differences have been found in the parietal cortex in children with ASD, but parietal subregions and associations between Sylvian fissure (SF) and parietal anatomy have not been explored. In this study, SF length and anterior and posterior parietal volumes were measured on MRI in 30 right-handed boys with ASD and 30 right-handed typically developing boys (7-14 years), matched on age and non-verbal IQ. There was leftward SF and anterior parietal asymmetry, and rightward posterior parietal asymmetry, across groups. There were associations between SF and parietal asymmetries, with slight group differences. Typical SF asymmetry was associated with typical anterior and posterior parietal asymmetry, in both groups. In the atypical SF asymmetry group, controls had atypical parietal asymmetry, whereas in ASD there were more equal numbers of individuals with typical as atypical anterior parietal asymmetry. We did not find significant anatomical-behavioral associations. Our findings of more individuals in the ASD group having a dissociation between cortical asymmetries warrants further investigation of these subgroups and emphasizes the importance of investigating anatomical relationships in addition to group differences in individual regions. PMID:22713374

  4. Neurovascular Compression Caused by Popliteus Muscle Enlargement Without Discrete Trauma

    PubMed Central

    2016-01-01

    Popliteal entrapment syndrome caused by isolated popliteus muscle enlargement is very rare, although its occurrence has been reported after discrete trauma. However, popliteal artery stenosis with combined peroneal and proximal tibial neuropathy caused by popliteus muscle enlargement without preceding trauma has not been reported. A 57-year-old man presented with a tingling sensation and pain in his left calf. He had no previous history of an injury. The symptoms were similar to those of lumbosacral radiculopathy. Calf pain became worse despite treatment, and the inability to flex his toes progressed. Computed tomography angiography and magnetic resonance imaging of the lower extremity showed popliteal artery stenosis caused by popliteus muscle enlargement and surrounding edema. An electrodiagnostic study confirmed combined peroneal and proximal tibial neuropathy at the popliteal fossa. Urgent surgical decompression was performed because of the progressive neurologic deficit and increasing neuropathic pain. The calf pain disappeared immediately after surgery, and he was discharged after the neurologic functions improved. PMID:27446794

  5. Right parietal cortex mediates recognition memory for melodies.

    PubMed

    Schaal, Nora K; Javadi, Amir-Homayoun; Halpern, Andrea R; Pollok, Bettina; Banissy, Michael J

    2015-07-01

    Functional brain imaging studies have highlighted the significance of right-lateralized temporal, frontal and parietal brain areas for memory for melodies. The present study investigated the involvement of bilateral posterior parietal cortices (PPCs) for the recognition memory of melodies using transcranial direct current stimulation (tDCS). Participants performed a recognition task before and after tDCS. The task included an encoding phase (12 melodies), a retention period, as well as a recognition phase (24 melodies). Experiment 1 revealed that anodal tDCS over the right PPC led to a deterioration of overall memory performance compared with sham. Experiment 2 confirmed the results of Experiment 1 and further showed that anodal tDCS over the left PPC did not show a modulatory effect on memory task performance, indicating a right lateralization for musical memory. Furthermore, both experiments revealed that the decline in memory for melodies can be traced back to an interference of anodal stimulation on the recollection process (remember judgements) rather than to familiarity judgements. Taken together, this study revealed a causal involvement of the right PPC for memory for melodies and demonstrated a key role for this brain region in the recollection process of the memory task. PMID:25959620

  6. Fronto-parietal network supports context-dependent speech comprehension

    PubMed Central

    Smirnov, Dmitry; Glerean, Enrico; Lahnakoski, Juha M.; Salmi, Juha; Jääskeläinen, Iiro P.; Sams, Mikko; Nummenmaa, Lauri

    2014-01-01

    Knowing the context of a discourse is an essential prerequisite for comprehension. Here we used functional magnetic resonance imaging (fMRI) to disclose brain networks supporting context-dependent speech comprehension. During fMRI, 20 participants listened to 1-min spoken narratives preceded by pictures that were either contextually matching or mismatching with the narrative. Matching pictures increased narrative comprehension, decreased hemodynamic activity in Broca׳s area, and enhanced its functional connectivity with left anterior superior frontal gyrus, bilateral inferior parietal cortex, as well as anterior and posterior cingulate cortex. Further, the anterior (BA 45) and posterior (BA 44) portions of Broca׳s area differed in their functional connectivity patterns. Both BA 44 and BA 45 have shown increased connectivity with right angular gyrus and supramarginal gyrus. Whereas BA 44 showed increased connectivity with left angular gyrus, left inferior/middle temporal gyrus and left postcentral gyrus, BA 45 showed increased connectivity with right posterior cingulate cortex, right anterior inferior frontal gyrus, lateral occipital cortex and anterior cingulate cortex. Our results suggest that a fronto-parietal functional network supports context-dependent narrative comprehension, and that Broca׳s area is involved in resolving ambiguity from speech when appropriate contextual cues are lacking. PMID:25218167

  7. Parietal cortex mediates conscious perception of illusory gestalt.

    PubMed

    Zaretskaya, Natalia; Anstis, Stuart; Bartels, Andreas

    2013-01-01

    Grouping local elements into a holistic percept, also known as spatial binding, is crucial for meaningful perception. Previous studies have shown that neurons in early visual areas V1 and V2 can signal complex grouping-related information, such as illusory contours or object-border ownerships. However, relatively little is known about higher-level processes contributing to these signals and mediating global Gestalt perception. We used a novel bistable motion illusion that induced alternating and mutually exclusive vivid conscious experiences of either dynamic illusory contours forming a global Gestalt or moving ungrouped local elements while the visual stimulation remained the same. fMRI in healthy human volunteers revealed that activity fluctuations in two sites of the parietal cortex, the superior parietal lobe and the anterior intraparietal sulcus (aIPS), correlated specifically with the perception of the grouped illusory Gestalt as opposed to perception of ungrouped local elements. We then disturbed activity at these two sites in the same participants using transcranial magnetic stimulation (TMS). TMS over aIPS led to a selective shortening of the duration of the global Gestalt percept, with no effect on that of local elements. The results suggest that aIPS activity is directly involved in the process of spatial binding during effortless viewing in the healthy brain. Conscious perception of global Gestalt is therefore associated with aIPS function, similar to attention and perceptual selection. PMID:23303932

  8. Increased parietal activity after training of interference control.

    PubMed

    Oelhafen, Stephan; Nikolaidis, Aki; Padovani, Tullia; Blaser, Daniela; Koenig, Thomas; Perrig, Walter J

    2013-11-01

    Recent studies suggest that computerized cognitive training leads to improved performance in related but untrained tasks (i.e. transfer effects). However, most study designs prevent disentangling which of the task components are necessary for transfer. In the current study, we examined whether training on two variants of the adaptive dual n-back task would affect untrained task performance and the corresponding electrophysiological event-related potentials (ERPs). Forty three healthy young adults were trained for three weeks with a high or low interference training variant of the dual n-back task, or they were assigned to a passive control group. While n-back training with high interference led to partial improvements in the Attention Network Test (ANT), we did not find transfer to measures of working memory and fluid intelligence. ERP analysis in the n-back task and the ANT indicated overlapping processes in the P3 time range. Moreover, in the ANT, we detected increased parietal activity for the interference training group alone. In contrast, we did not find electrophysiological differences between the low interference training and the control group. These findings suggest that training on an interference control task leads to higher electrophysiological activity in the parietal cortex, which may be related to improvements in processing speed, attentional control, or both.

  9. Parietal cortex mediates conscious perception of illusory gestalt.

    PubMed

    Zaretskaya, Natalia; Anstis, Stuart; Bartels, Andreas

    2013-01-01

    Grouping local elements into a holistic percept, also known as spatial binding, is crucial for meaningful perception. Previous studies have shown that neurons in early visual areas V1 and V2 can signal complex grouping-related information, such as illusory contours or object-border ownerships. However, relatively little is known about higher-level processes contributing to these signals and mediating global Gestalt perception. We used a novel bistable motion illusion that induced alternating and mutually exclusive vivid conscious experiences of either dynamic illusory contours forming a global Gestalt or moving ungrouped local elements while the visual stimulation remained the same. fMRI in healthy human volunteers revealed that activity fluctuations in two sites of the parietal cortex, the superior parietal lobe and the anterior intraparietal sulcus (aIPS), correlated specifically with the perception of the grouped illusory Gestalt as opposed to perception of ungrouped local elements. We then disturbed activity at these two sites in the same participants using transcranial magnetic stimulation (TMS). TMS over aIPS led to a selective shortening of the duration of the global Gestalt percept, with no effect on that of local elements. The results suggest that aIPS activity is directly involved in the process of spatial binding during effortless viewing in the healthy brain. Conscious perception of global Gestalt is therefore associated with aIPS function, similar to attention and perceptual selection.

  10. Sleep Related Hypermotor Seizures with a Right Parietal Onset

    PubMed Central

    Gibbs, Steve A.; Figorilli, Michela; Casaceli, Giuseppe; Proserpio, Paola; Nobili, Lino

    2015-01-01

    Nocturnal frontal lobe epilepsy (NFLE) is a syndrome characterized by the occurrence of sleep related seizures of variable complexity and duration. Hypermotor seizures (HMS) represent a classic manifestation of this syndrome, associated with a perturbation of the ventromesial frontal cortex and anterior cingulate gyrus regions. Nevertheless, in recent years, reports have showed that the seizure onset zone (SOZ) need not be of frontal origin to generate HMS. Here we report an unusual case of a patient presenting with a seven-year history of drug-resistant sleep related HMS arising from the mesial parietal region. The presence of an infrequent feeling of levitation before the HMS was key to suspecting a subtle focal cortical dysplasia in the right precuneus region. A stereo-EEG investigation confirmed the extra-frontal seizure onset of the HMS and highlighted the interrelationship between unstable sleep and seizure precipitation. Citation: Gibbs SA, Figorilli M, Casaceli G, Proserpio P, Nobili L. Sleep related hypermotor seizures with a right parietal onset. J Clin Sleep Med 2015;11(8):953–955. PMID:25902821

  11. Frontal and parietal lobe activation during transitive inference in humans.

    PubMed

    Acuna, Bettina D; Eliassen, James C; Donoghue, John P; Sanes, Jerome N

    2002-12-01

    Cortical areas engaged in knowledge manipulation during reasoning were identified with functional magnetic resonance imaging (MRI) while participants performed transitive inference (TI) on an ordered list of 11 items (e.g. if A < B and B < C, then A < C). Initially, participants learned a list of arbitrarily ordered visual shapes. Learning occurred by exposure to pairs of list items that were adjacent in the sequence. Subsequently, functional MR images were acquired as participants performed TI on non-adjacent sequence items. Control tasks consisted of height comparisons (HT) and passive viewing (VIS). Comparison of the TI task with the HT task identified activation resulting from TI, termed 'reasoning', while controlling for rule application, decision processes, perception, and movement, collectively termed 'support processes'. The HT-VIS comparison revealed activation related to support processes. The TI reasoning network included bilateral prefrontal cortex (PFC), pre-supplementary motor area (preSMA), premotor area (PMA), insula, precuneus, and lateral posterior parietal cortex. By contrast, cortical regions activated by support processes included the bilateral supplementary motor area (SMA), primary motor cortex (M1), somatic sensory cortices, and right PMA. These results emphasize the role of a prefrontal-parietal network in manipulating information to form new knowledge based on familiar facts. The findings also demonstrate PFC activation beyond short-term memory to include mental operations associated with reasoning. PMID:12427681

  12. Right parietal cortex mediates recognition memory for melodies.

    PubMed

    Schaal, Nora K; Javadi, Amir-Homayoun; Halpern, Andrea R; Pollok, Bettina; Banissy, Michael J

    2015-07-01

    Functional brain imaging studies have highlighted the significance of right-lateralized temporal, frontal and parietal brain areas for memory for melodies. The present study investigated the involvement of bilateral posterior parietal cortices (PPCs) for the recognition memory of melodies using transcranial direct current stimulation (tDCS). Participants performed a recognition task before and after tDCS. The task included an encoding phase (12 melodies), a retention period, as well as a recognition phase (24 melodies). Experiment 1 revealed that anodal tDCS over the right PPC led to a deterioration of overall memory performance compared with sham. Experiment 2 confirmed the results of Experiment 1 and further showed that anodal tDCS over the left PPC did not show a modulatory effect on memory task performance, indicating a right lateralization for musical memory. Furthermore, both experiments revealed that the decline in memory for melodies can be traced back to an interference of anodal stimulation on the recollection process (remember judgements) rather than to familiarity judgements. Taken together, this study revealed a causal involvement of the right PPC for memory for melodies and demonstrated a key role for this brain region in the recollection process of the memory task.

  13. Spleen and liver enlargement in a patient with rheumatoid arthritis.

    PubMed

    Bedoya, María Eugenia; Ceccato, Federico; Paira, Sergio

    2015-01-01

    We describe the case of a 51-year-old woman with a seropositive, erosive, and non-nodular rheumatoid arthritis of 15 year of evolution. The patient had poor compliance with medical visits and treatment. She came to the clinic with persistent pancytopenia and spleen and liver enlargement. Liver and bone marrow biopsies were carried out and amyloidosis, neoplasias and infections were ruled out. We discuss the differential diagnosis of pancytopenia and spleen and liver enlargement in a long-standing rheumatoid arthritis patient.

  14. Cardiac Asystole Triggered by Temporal Lobe Epilepsy with Amygdala Enlargement.

    PubMed

    Arakawa, Junko; Nagai, Tomoo; Takasaki, Hiroshi; Sugano, Hidenori; Hamabe, Akira; Tahara, Mai; Mori, Hitoshi; Takase, Yoshiyuki; Gatate, Youdou; Togashi, Naohiko; Takiguchi, Shunichi; Nakaya, Kazuhiro; Ishigami, Norio; Tabata, Hirotsugu; Fukushima, Kouji; Katsushika, Shuichi

    2016-01-01

    A 25-year-old previously healthy man was hospitalized for syncope. While standing, he suddenly lost consciousness, followed by a generalized tonic clonic seizure. An electrocardiogram demonstrated asystole. No cardiac abnormalities were detected on the echocardiogram, cardiac magnetic resonance imaging (MRI), positron emission tomography, or a coronary angiogram. An electrophysiological study showed normal sinus node and atrioventricular node function. An electroencephalogram revealed small spike waves in the fronto-temporal region. Brain MRI demonstrated a left-sided amygdala enlargement. To the best of our knowledge, this is the first case of temporal lobe epilepsy with an amygdala enlargement that induced cardiac asystole. PMID:27250053

  15. Modeling Murine Gastric Metaplasia Through Tamoxifen-Induced Acute Parietal Cell Loss.

    PubMed

    Saenz, Jose B; Burclaff, Joseph; Mills, Jason C

    2016-01-01

    Parietal cell loss represents the initial step in the sequential progression toward gastric adenocarcinoma. In the setting of chronic inflammation, the expansion of the mucosal response to parietal cell loss characterizes a crucial transition en route to gastric dysplasia. Here, we detail methods for using the selective estrogen receptor modulator tamoxifen as a novel tool to rapidly and reversibly induce parietal cell loss in mice in order to study the mechanisms that underlie these pre-neoplastic events. PMID:27246044

  16. Does Society Matter? Life Satisfaction in the Enlarged Europe

    ERIC Educational Resources Information Center

    Bohnke, Petra

    2008-01-01

    Life satisfaction is quite heterogeneously distributed across countries of the enlarged European Union. Previous research has shown how living conditions within individual countries, such as access to material and emotional resources, are important for personal well-being, but it has been less successful in explaining differences between…

  17. The Print and Computer Enlargement System--PACE. Final Report.

    ERIC Educational Resources Information Center

    Morford, Ronald A.

    The Print and Computer Enlargement (PACE) System is being designed as a portable computerized reading and writing system that enables a low-vision person to read regular print and then create and edit text using large-print computerized output. The design goal was to develop a system that: weighed no more than 12 pounds so it could be easily…

  18. 4. Photocopy of photograph (4 x 5 inch enlargement of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Photocopy of photograph (4 x 5 inch enlargement of 1942 3-1/2 x 5-7/8 inch print by R. Fromme; in Recreation files, Supervisor's Office, Mt. Baker-Snoqualmie National Forest) EAST (MAIN) ELEVATION OF PROTECTION ASSISTANT'S RESIDENCE - Glacier Ranger Station, Protection Assistant's Residence, Washington State Route 542, Glacier, Whatcom County, WA

  19. 2. 8' x 10' enlargement from 4' x 5' negative ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. 8' x 10' enlargement from 4' x 5' negative Kevin Kriesel-Coons, Photographer, November 13, 1990 INTERIOR OF HYDRO PLANT, SHOWING CURRENT STATE OF DISREPAIR. - Crosscut Steam Plant, Ancillary Hydro Unit, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  20. 1. 8' x 10' enlargement from 4' x 5' negative ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. 8' x 10' enlargement from 4' x 5' negative Kevin Kriesel-Coons, Photographer, November 13, 1990 EXTERIOR OF HYDRO PLANT, SHOWING CURRENT STATE OF DISREPAIR. VIEW FROM WALKWAY OVER TAILRACE OF CROSSCUT CANAL TO THE LARGER, ORIGINAL CROSSCUT HYDRO PLANT. - Crosscut Steam Plant, Ancillary Hydro Unit, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  1. Congenital enlargement of the suburethral diverticulum in a Holstein calf.

    PubMed

    Vogel, Susan R; Doré, Elizabeth; Breteau, Gaëlle; Desrochers, André; Babkine, Marie; Nichols, Sylvain

    2011-02-01

    A 3-month-old, female Holstein calf was examined because of marked perineal swelling and tenesmus of 4-days duration. A congenitally enlarged urethral diverticulum was diagnosed using fluoroscopic and ultrasonographic imaging techniques. The urethral diverticulum was surgically resected and the perineal area was reconstructed.

  2. Construction and enlargement of traversable wormholes from Schwarzschild black holes

    SciTech Connect

    Koyama, Hiroko; Hayward, Sean A.

    2004-10-15

    Analytic solutions are presented which describe the construction of a traversable wormhole from a Schwarzschild black hole, and the enlargement of such a wormhole, in Einstein gravity. The matter model is pure radiation which may have negative-energy density (phantom or ghost radiation) and the idealization of impulsive radiation (infinitesimally thin null shells) is employed.

  3. 23. Photocopy of photograph (4 x 5 inch enlargement of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Photocopy of photograph (4 x 5 inch enlargement of 1940 3-1/4 x 4-1/4 inch print by R. Nevan McCullough; in Cultural Resource files, Supervisor's Office, Mt. Baker-Snoqualmie National Forest) SOUTH FRONT - Suntop Lookout, Forest Road 510, Mt. Baker-Snoqualmie National Forest, Greenwater, Pierce County, WA

  4. 22. PHOTOGRAPHIC ENLARGEMENT OF UPPER PHOTOGRAPH ON PAGE 986 IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. PHOTOGRAPHIC ENLARGEMENT OF UPPER PHOTOGRAPH ON PAGE 986 IN Keystone Coal Buyers Catalog, 1922, VIEW SOUTH, COMMUNITY OF ETHEL; ETHEL COAL COMPANY MINE SUPPLY BUILDING IS LOCATED IN MID-GROUND LEFT OF CENTER PARTIALLY OBSCURED BY ROOF OF HOUSE IN FOREGROUND - Ethel Coal Company & Supply Building, Left fork of Dingess Run (Ethel Hollow), Ethel, Logan County, WV

  5. 23. PHOTOGRAPHIC ENLARGEMENT OF UPPER PHOTOGRAPH ON PAGE 986 IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. PHOTOGRAPHIC ENLARGEMENT OF UPPER PHOTOGRAPH ON PAGE 986 IN Keystone Coal Buyers Catalog, 1922, VIEW SOUTH, COMMUNITY OF ETHEL; ETHEL COAL COMPANY MINE SUPPLY BUILDING IS LOCATED IN MID-GROUND IN CENTER PARTIALLY OBSCURED BY ROOF OF HOUSE IN FOREGROUND - Ethel Coal Company & Supply Building, Left fork of Dingess Run (Ethel Hollow), Ethel, Logan County, WV

  6. 9. 8' X 10' Enlargement from 4' x 5' negative ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. 8' X 10' Enlargement from 4' x 5' negative Kevin Kriesel-Coons, Photographer PUMPS AFTER REMOVAL FROM PUMPHOUSE BEFORE EXCAVATION OF POND AREA IN 1989. PHOTOGRAPHED LYING ON GROUND NEAR CROSSCUT STEAM PLANT BUILDING. - Crosscut Steam Plant, Indian Bend Pond & Pump Ditch, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  7. [Enlargement of the buccal aperture via. Technical consideration (author's transl)].

    PubMed

    Pons, J; Pasturel, A; Pochan, Y; Barbier, M

    1979-01-01

    For a long time we know that it is possible to take out from the mouth a part or all the mandibule which presents a local malignant tumour. When the tumour is too extensed, the buccal aperture can be enlarged. The authors describe a new surgical technique which resolves this problem with notable and faithful advantages.

  8. Income, Deprivation and Economic Stress in the Enlarged European Union

    ERIC Educational Resources Information Center

    Whelan, Christopher T.; Maitre, Bertrand

    2007-01-01

    At risk of poverty indicators based on relative income measures suggest that within the enlarged EU societies located at quite different points on a continuum of affluence have similar levels of poverty. Substantial differences in levels of income between societies do not in themselves invalidate this approach. However, the relative income…

  9. Photographic Enlargement of Printed Music: Technique, Application, and Implications.

    ERIC Educational Resources Information Center

    Flynn, Pauline T.; Rich, A. Jeanette

    1982-01-01

    Addressed a need for enlargement of music when retirement home residents were deprived of a self-fulfillment opportunity from choir activities due to failing eyesight. A photographic process yielded the needed feasible large reproductions. Innovative application of this technique affords wide-ranging potential for positive benefit beyond music…

  10. Amygdala and Hippocampus Enlargement during Adolescence in Autism

    ERIC Educational Resources Information Center

    Groen, Wouter; Teluij, Michelle; Buitelaar, Jan; Tendolkar, Indira

    2010-01-01

    Objective: The amygdala and hippocampus are key components of the neural system mediating emotion perception and regulation and are thought to be involved in the pathophysiology of autism. Although some studies in children with autism suggest that there is an enlargement of amygdala and hippocampal volume, findings in adolescence are sparse.…

  11. 17. Historic photograph, photographer unknown, 1943. ENLARGEMENT OF PORTION OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. Historic photograph, photographer unknown, 1943. ENLARGEMENT OF PORTION OF PHOTOGRAPH AZ-10-16, SHOWING WOOD TOWER BEFORE CONCRETE WAS ADDED. NOTE GUY CABLE CONNECTED TO TOP RIGHT OF TOWER. - Verde River Sheep Bridge, Spanning Verde River (Tonto National Forest), Cave Creek, Maricopa County, AZ

  12. 30. Photocopy from enlarged microfiche of 1896 drawing captioned: Part ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. Photocopy from enlarged microfiche of 1896 drawing captioned: Part of Plan C/80 showing changes proposed in end doors of Storehouse, then under construction by the Penn Bridge Co. of Beaver Falls, Pa. - Puget Sound Naval Shipyard, Pattern Shop, Farragut Avenue, Bremerton, Kitsap County, WA

  13. The role of right and left parietal lobes in the conceptual processing of numbers.

    PubMed

    Cappelletti, Marinella; Lee, Hwee Ling; Freeman, Elliot D; Price, Cathy J

    2010-02-01

    Neuropsychological and functional imaging studies have associated the conceptual processing of numbers with bilateral parietal regions (including intraparietal sulcus). However, the processes driving these effects remain unclear because both left and right posterior parietal regions are activated by many other conceptual, perceptual, attention, and response-selection processes. To dissociate parietal activation that is number-selective from parietal activation related to other stimulus or response-selection processes, we used fMRI to compare numbers and object names during exactly the same conceptual and perceptual tasks while factoring out activations correlating with response times. We found that right parietal activation was higher for conceptual decisions on numbers relative to the same tasks on object names, even when response time effects were fully factored out. In contrast, left parietal activation for numbers was equally involved in conceptual processing of object names. We suggest that left parietal activation for numbers reflects a range of processes, including the retrieval of learnt facts that are also involved in conceptual decisions on object names. In contrast, number selectivity in right parietal cortex reflects processes that are more involved in conceptual decisions on numbers than object names. Our results generate a new set of hypotheses that have implications for the design of future behavioral and functional imaging studies of patients with left and right parietal damage. PMID:19400672

  14. Dissociable parietal systems for primacy and subsequent memory effects.

    PubMed

    Sommer, Tobias; Rose, Michael; Büchel, Christian

    2006-05-01

    The frequently observed superior memory for the first items on a list is referred to as primacy. The aetiology of this effect in terms of cognitive processes and their neural substrate is subject to an ongoing debate. However, the brain areas generally involved in successful encoding are well described by subsequent memory studies in which activity during encoding is correlated with memory performance. We employed an object-location association paradigm to differentiate the neural correlate of the primacy from the subsequent memory effect. Activity in the intraparietal sulcus predicted memory performance across all encoding positions. Increased activity in the inferior parietal lobe and angular gyrus resulted exclusively in a more efficient encoding of the first item presented. These areas are part of the ventral frontoparietal network involved in stimulus driven attention. Our results implicate the relatively elevated attention to the first item probably due to its contextual distinctiveness, as a major contributor to the primacy effect.

  15. [Parietal-scar endometriosis after cesarean section: a rare entity].

    PubMed

    El Fahssi, Mohammed; Lomdo, Massama; Bounaim, Ahmed; Ali, Abdelmounaim Ait; Sair, Khalid

    2016-01-01

    Wall endometriosis is a rare clinical entity whose pathophysiology remains unclear. It occurs most frequently after gynecologic or obstetric surgery. We report the case of a patient with cyclic pain at the caesarean section scar. Clinical examination showed a 5 cm mass in the right iliac fossa. Tomodensitometry revealed a tissue density mass (45mm on the major axis). Hence, the decision to perform a wide excision of the lesion. Anatomo-pathological examination confirmed the diagnosis of parietal endometriosis. Postoperative sequelae were simple with a follow-up period of 20 months with no recurrence of the mass or of the pain. Our study highlights the characteristics of this disease to allow the health practitioner to understand the importance of diagnosis, of early treatment of this disease as well as of the possibility to prevent it during each gynecologic or obstetric surgery. PMID:27642418

  16. Transient contribution of left posterior parietal cortex to cognitive restructuring

    PubMed Central

    Sutoh, Chihiro; Matsuzawa, Daisuke; Hirano, Yoshiyuki; Yamada, Makiko; Nagaoka, Sawako; Chakraborty, Sudesna; Ishii, Daisuke; Matsuda, Shingo; Tomizawa, Haruna; Ito, Hiroshi; Tsuji, Hiroshi; Obata, Takayuki; Shimizu, Eiji

    2015-01-01

    Cognitive restructuring is a fundamental method within cognitive behavioural therapy of changing dysfunctional beliefs into flexible beliefs and learning to react appropriately to the reality of an anxiety-causing situation. To clarify the neural mechanisms of cognitive restructuring, we designed a unique task that replicated psychotherapy during a brain scan. The brain activities of healthy male participants were analysed using functional magnetic resonance imaging. During the brain scan, participants underwent Socratic questioning aimed at cognitive restructuring regarding the necessity of handwashing after using the restroom. The behavioural result indicated that the Socratic questioning effectively decreased the participants' degree of belief (DOB) that they must wash their hands. Alterations in the DOB showed a positive correlation with activity in the left posterior parietal cortex (PPC) while the subject thought about and rated own belief. The involvement of the left PPC not only in planning and decision-making but also in conceptualization may play a pivotal role in cognitive restructuring. PMID:25775998

  17. Sleep Related Hypermotor Seizures with a Right Parietal Onset.

    PubMed

    Gibbs, Steve A; Figorilli, Michela; Casaceli, Giuseppe; Proserpio, Paola; Nobili, Lino

    2015-08-01

    Nocturnal frontal lobe epilepsy (NFLE) is a syndrome characterized by the occurrence of sleep related seizures of variable complexity and duration. Hypermotor seizures (HMS) represent a classic manifestation of this syndrome, associated with a perturbation of the ventromesial frontal cortex and anterior cingulate gyrus regions. Nevertheless, in recent years, reports have showed that the seizure onset zone (SOZ) need not be of frontal origin to generate HMS. Here we report an unusual case of a patient presenting with a seven-year history of drug-resistant sleep related HMS arising from the mesial parietal region. The presence of an infrequent feeling of levitation before the HMS was key to suspecting a subtle focal cortical dysplasia in the right precuneus region. A stereo-EEG investigation confirmed the extra-frontal seizure onset of the HMS and highlighted the interrelationship between unstable sleep and seizure precipitation. PMID:25902821

  18. Herpes Simplex Encephalitis of the Parietal Lobe: A Rare Presentation

    PubMed Central

    Tkachenko, Lara; Moisi, Marc; Rostad, Steven; Umeh, Randle; Zwillman, Michael E; Tubbs, R. Shane; Page, Jeni; Newell, David W.; Delashaw, Johnny B

    2016-01-01

    A 69-year-old female with a history of breast cancer and hypertension presented with a rare case of herpes simplex encephalitis (HSE) isolated to her left parietal lobe. The patient’s first biopsy was negative for herpes simplex virus (HSV) I/II antigens, but less than two weeks later, the patient tested positive on repeat biopsy. This initial failure to detect the virus and the similarities between HSE and symptoms of intracranial hemorrhage (ICH) suggests repeat testing for HSV in the presence of ICH. Due to the frequency of patients with extra temporal HSE, a diagnosis of HSE should be more readily considered, particularly when a patient may not be improving and a concrete diagnosis has not been solidified. PMID:27774355

  19. A parietal memory network revealed by multiple MRI methods.

    PubMed

    Gilmore, Adrian W; Nelson, Steven M; McDermott, Kathleen B

    2015-09-01

    The manner by which the human brain learns and recognizes stimuli is a matter of ongoing investigation. Through examination of meta-analyses of task-based functional MRI and resting state functional connectivity MRI, we identified a novel network strongly related to learning and memory. Activity within this network at encoding predicts subsequent item memory, and at retrieval differs for recognized and unrecognized items. The direction of activity flips as a function of recent history: from deactivation for novel stimuli to activation for stimuli that are familiar due to recent exposure. We term this network the 'parietal memory network' (PMN) to reflect its broad involvement in human memory processing. We provide a preliminary framework for understanding the key functional properties of the network. PMID:26254740

  20. Diverse spatial reference frames of vestibular signals in parietal cortex

    PubMed Central

    Chen, Xiaodong; DeAngelis, Gregory C; Angelaki, Dora E

    2013-01-01

    Summary Reference frames are important for understanding how sensory cues from different modalities are coordinated to guide behavior, and the parietal cortex is critical to these functions. We compare reference frames of vestibular self-motion signals in the ventral intraparietal area (VIP), parietoinsular vestibular cortex (PIVC), and dorsal medial superior temporal area (MSTd). Vestibular heading tuning in VIP is invariant to changes in both eye and head positions, indicating a body (or world)-centered reference frame. Vestibular signals in PIVC have reference frames that are intermediate between head- and body-centered. In contrast, MSTd neurons show reference frames between head- and eye-centered, but not body-centered. Eye and head position gain fields were strongest in MSTd and weakest in PIVC. Our findings reveal distinct spatial reference frames for representing vestibular signals, and pose new challenges for understanding the respective roles of these areas in potentially diverse vestibular functions. PMID:24239126

  1. Scalp Medical Tattooing Technique to Camouflage Bifid Parietal Whorls

    PubMed Central

    You, Seung Hyun

    2016-01-01

    Background: To the best of the authors’ knowledge, no reports have described cosmetic problems arising from the hair direction around the parietal whorl (PW). This study was performed to evaluate the efficacy of scalp medical tattooing technique for camouflaging bifid PWs. Methods: We retrospectively examined the outcomes of scalp medical tattooing in 38 patients who were admitted for camouflage of a bifid PW. Results: All patients’ cosmetic appearance was judged, by both the patients and the surgeon, to be markedly improved. No specific complications occurred, such as infection, hair loss in the operative field, or other problems. Conclusion: Scalp medical tattooing appears to be an effective method that helps to camouflage the see-through appearance of bifid PWs. PMID:27200232

  2. Subcortical mapping of calculation processing in the right parietal lobe.

    PubMed

    Della Puppa, Alessandro; De Pellegrin, Serena; Lazzarini, Anna; Gioffrè, Giorgio; Rustemi, Oriela; Cagnin, Annachiara; Scienza, Renato; Semenza, Carlo

    2015-05-01

    Preservation of calculation processing in brain surgery is crucial for patients' quality of life. Over the last decade, surgical electrostimulation was used to identify and preserve the cortical areas involved in such processing. Conversely, subcortical connectivity among different areas implicated in this function remains unclear, and the role of surgery in this domain has not been explored so far. The authors present the first 2 cases in which the subcortical functional sites involved in calculation were identified during right parietal lobe surgery. Two patients affected by a glioma located in the right parietal lobe underwent surgery with the aid of MRI neuronavigation. No calculation deficits were detected during preoperative assessment. Cortical and subcortical mapping were performed using a bipolar stimulator. The current intensity was determined by progressively increasing the amplitude by 0.5-mA increments (from a baseline of 1 mA) until a sensorimotor response was elicited. Then, addition and multiplication calculation tasks were administered. Corticectomy was performed according to both the MRI neuronavigation data and the functional findings obtained through cortical mapping. Direct subcortical electrostimulation was repeatedly performed during tumor resection. Subcortical functional sites for multiplication and addition were detected in both patients. Electrostimulation interfered with calculation processing during cortical mapping as well. Functional sites were spared during tumor removal. The postoperative course was uneventful, and calculation processing was preserved. Postoperative MRI showed complete resection of the tumor. The present preliminary study shows for the first time how functional mapping can be a promising method to intraoperatively identify the subcortical functional sites involved in calculation processing. This report therefore supports direct electrical stimulation as a promising tool to improve the current knowledge on

  3. Phenytoin, folic acid and gingival enlargement: Breaking myths

    PubMed Central

    Nayyar, Abhishek Singh; Khan, Mubeen; Vijayalakshmi, K. R.; Suman, B.; Subhas, G. T.; Nataraju, B.; Anitha, M.

    2014-01-01

    Background: Epilepsy is described as a chronic neurological disorder characterized by recurrent seizures of cerebral origin, presenting with episodes of sensory, motor or autonomic phenomenon with or, without loss of consciousness. A recent meta-analysis of published and unpublished studies puts an overall prevalence rate of epilepsy in India at 5.59 per 1,000 populations. There have been studies that report clinical benefits of the use of folic acid as an adjuvant to the anti-epileptic therapy in the prevention of anti-epileptic drug induced gingival enlargement. However, studies conducted in the past have also reported precipitation of epileptic attacks in patients on folic acid adjuvant therapy due to fall in sera levels of phenytoin due to drug interactions. The study was planned to investigate the association of phenytoin induced gingival enlargement and sera levels of folic acid in epileptic patients on phenytoin therapy so as to justify the use of folic acid as a routine adjuvant to the usual anti-epileptic therapy to prevent this inevitable adverse effect without destabilizing the ongoing regimen leading to the precipitation of seizures in an otherwise stable patient (breakthrough seizures). Materials and Methods: A total of 100 patients between the ages 18 and 50 years were clinically diagnosed with epilepsy prior to the start of phenytoin therapy were included based on selection criteria and written informed consents were obtained. Assessment of serum folic acid levels and gingival enlargement was performed prior to the start of and after 1 year of phenytoin therapy. Statistical Analysis Used: The statistical analysis was carried out using t-test and the baseline serum folate levels and the serum folate levels obtained after 1 year of phenytoin therapy were correlated with the respective grades of gingival enlargement using Pearson's coefficient formula. Results: The results of the study confirmed a significant association between low serum folate levels

  4. The Role of Right and Left Parietal Lobes in the Conceptual Processing of Numbers

    ERIC Educational Resources Information Center

    Cappelletti, Marinella; Lee, Hwee Ling; Freeman, Elliot D.; Price, Cathy J.

    2010-01-01

    Neuropsychological and functional imaging studies have associated the conceptual processing of numbers with bilateral parietal regions (including intraparietal sulcus). However, the processes driving these effects remain unclear because both left and right posterior parietal regions are activated by many other conceptual, perceptual, attention,…

  5. The Contribution of the Inferior Parietal Cortex to Spoken Language Production

    ERIC Educational Resources Information Center

    Geranmayeh, Fatemeh; Brownsett, Sonia L. E.; Leech, Robert; Beckmann, Christian F.; Woodhead, Zoe; Wise, Richard J. S.

    2012-01-01

    This functional MRI study investigated the involvement of the left inferior parietal cortex (IPC) in spoken language production (Speech). Its role has been apparent in some studies but not others, and is not convincingly supported by clinical studies as they rarely include cases with lesions confined to the parietal lobe. We compared Speech with…

  6. Differences in biomechanical properties and thickness among frontal and parietal bones in a Japanese sample.

    PubMed

    Torimitsu, Suguru; Nishida, Yoshifumi; Takano, Tachio; Yajima, Daisuke; Inokuchi, Go; Makino, Yohsuke; Motomura, Ayumi; Chiba, Fumiko; Yamaguchi, Rutsuko; Hashimoto, Mari; Hoshioka, Yumi; Iwase, Hirotaro

    2015-07-01

    The aim of this study was to assess the mechanical properties and thickness of adult frontal and parietal bones. The heads of 114 Japanese cadavers (78 male cadavers and 36 female cadavers) of known age and sex were used. A total of 912 cranial samples, 8 from each skull, were collected. Samples were imaged using multidetector computed tomography to measure sample thickness. The fracture load of each sample was measured using a bending test with calculation of flexural strength. Statistical analyses demonstrated no significant bilateral difference in either the mechanical properties or thickness of frontal or parietal bones. The mechanical properties and thicknesses of frontal bones were significantly greater than those of parietal bones regardless of sex. Therefore, the skull may have a great ability to resist frontal impacts compared with parietal impacts. In female samples, parietal bones were found to have a more uniform structure when compared with male samples. Male parietal bones were found to be thicker at medial sites than at lateral sites. This study also revealed parietal bones at lateral sites in female samples were thicker than in male samples. No strong association was observed between age and flexural strength of frontal or parietal bones. However, the fracture load was negatively correlated with age most likely due to the reduction of thickness.

  7. Capsule of Cryptococcus neoformans grows by enlargement of polysaccharide molecules.

    PubMed

    Frases, Susana; Pontes, Bruno; Nimrichter, Leonardo; Viana, Nathan B; Rodrigues, Marcio L; Casadevall, Arturo

    2009-01-27

    The human pathogenic fungus Cryptococcus neoformans has a distinctive polysaccharide (PS) capsule that enlarges during infection. The capsule is essential for virulence, but the mechanism for capsular growth is unknown. In the present study, we used dynamic light scattering (LS) analysis of capsular PS and optical tweezers (OT) to explore the architecture of the capsule. Analysis of capsular PS from cells with small and large capsules by dynamic LS revealed a linear correlation between PS effective diameter and microscopic capsular diameter. This result implied that capsule growth was achieved by the addition of molecules with larger effective diameter, such that some molecules can span the entire diameter of the capsule. Measurement of polystyrene bead penetration of C. neoformans capsules by using OT techniques revealed that the outer regions were penetrable, but not the inner regions. Our results provide a mechanism for capsular enlargement based on the axial lengthening of PS molecules and suggest a model for the architecture of a eukaryotic microbial capsule.

  8. Credit WCT. This view is an enlargement of an original ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Credit WCT. This view is an enlargement of an original 2-A" x 2-Y4" color negative housed in the JPL Photography Laboratory, Pasadena, California. The doors of the conditioning chamber have been opened to reveal the arrangement of wrapped motors ready for treatment (JPL negative no. JPL-10281BC, 27 January 1989) - Jet Propulsion Laboratory Edwards Facility, Solid Propellant Conditioning Building, Edwards Air Force Base, Boron, Kern County, CA

  9. Chrysotile and tremolite asbestos fibres in the lungs and parietal pleura of Corsican goats

    PubMed Central

    Dumortier, P; Rey, F; Viallat, J; Broucke, I; Boutin, C; De Vuyst, P

    2002-01-01

    Methods: Ten goats from areas with asbestos outcrops and two from other areas were slaughtered. Fibre content of lung and parietal pleural samples was determined by analytical transmission electron microscopy. Results: Both chrysotile and tremolite fibres were detected. In the exposed goats, the geometric mean concentrations of asbestos fibres longer than 1 µm were 0.27 x 106 fibres/g dry lung tissue and 1.8 x 106 fibres/g dry pleural tissue. Asbestos fibres were not detected in the lungs of the two control goats. Chrysotile fibres shorter than 5 µm were predominant in the parietal pleura. Tremolite fibres accounted for 78% and 86% of the fibres longer than 5 µm in lung and parietal pleural samples, respectively. Conclusions: Environmental exposure in northeast Corsica results in detectable chrysotile and tremolite fibre loads in the lung and parietal pleura of adult goats. Tremolite fibres of dimensions with a high carcinogenic potency are detected in the parietal pleura. PMID:12205241

  10. Nystagmus in Enlarged Vestibular Aqueduct: A Case Series

    PubMed Central

    White, Judith; Krakovitz, Paul

    2015-01-01

    Enlarged vestibular aqueduct (EVA) is one of the commonly identified congenital temporal bone abnormalities associated with sensorineural hearing loss. Hearing loss may be unilateral or bilateral, and typically presents at birth or in early childhood. Vestibular symptoms have been reported in up to 50% of affected individuals, and may be delayed in onset until adulthood. The details of nystagmus in patients with EVA have not been previously reported. The objectives were to describe the clinical history, vestibular test findings and nystagmus seen in a case series of patients with enlarged vestibular aqueduct anomaly. Chart review, included computed tomography temporal bones, infrared nystagmography with positional and positioning testing, caloric testing, rotary chair and vibration testing. Clinical history and nystagmus varied among the five patients in this series. All patients were initially presumed to have benign paroxysmal positional vertigo, but repositioning treatments were not effective, prompting referral, further testing and evaluation. In three patients with longstanding vestibular complaints, positional nystagmus was consistently present. One patient had distinct recurrent severe episodes of positional nystagmus. Nystagmus was unidirectional and horizontal. In one case horizontal nystagmus was consistently reproducible with seated head turn to the affected side, and reached 48 d/s. Nystagmus associated with enlarged vestibular aqueduct is often positional, and can be confused with benign paroxysmal positional vertigo. Unexplained vestibular symptoms in patients with unilateral or bilateral sensorineural hearing loss should prompt diagnostic consideration of EVA. PMID:26557362

  11. Emergency department enlargement in China: exciting or bothering

    PubMed Central

    Li, Yan; Li, Chen; Xu, Jun; Zhang, Hui; Zheng, Liangliang; Yao, Dongqi; Fu, Yangyang; Zhu, Huadong; Guo, Shubin; Wang, Zhong; Walline, Joseph

    2016-01-01

    Background Emergency department (ED) enlargement became a trend with its development. However, there came some problems such as ED overcrowding and increasing medical disputes. Here we did a survey about the development tendency of EDs in 3A grade hospitals in China, analysed the problems we facing and rendered some solutions combining some special characteristics in China. Methods We randomly selected 17 3A grade general hospitals from 12 provinces from the 50 members of Chinese College of Emergency Physician. A questionnaire survey was conducted. The basic information and problems of EDs were collected and analysed. Results The gross area, the number of beds and the attention paid by the hospitals of EDs increased during the development, so did the patients admitted to EDs, also more doctors and nurses devoted into emergency medicine. But it had become more difficult for doctors to admit ED patients to inpatient wards. Besides the problem of increasing crowding degree, EDs faced more medical disputes and complains during the development. Conclusions ED expanding was the result of emergency medicine development, but the enlargement of ED should be more rational. We should improve our doctors’ medical skills, optimize the health system, pay more attention to preventive medicine and push hard for health-care reform instead of forcing ED enlargement to satisfy the need for ED. PMID:27162657

  12. Stochastic Schrödinger evolution over piecewise enlarged filtrations

    NASA Astrophysics Data System (ADS)

    Mengütürk, Levent Ali

    2016-03-01

    This paper constructs a nonlinear filtering framework that admits appearances of new information processes at random times by introducing piecewise enlargements of filtrations and proposes a new energy-based Schrodinger evolution expressed as a stochastic differential equation on a complex Hilbert space. Each information process is modeled as the sum of a random variable taking the eigenvalues of a Hamiltonian and an independent Brownian bridge noise. It is shown that under a piecewise enlarged filtration, the wave function is a jump-diffusion process until it collapses at some terminal time. In between discontinuities, the dynamics of the state vector are governed by different Wiener processes and diffusion coefficients. This motivates the introduction of an inclusive chain of Kolmogorov probability spaces or a *-isomorphic chain of commutative von Neumann probability spaces, on which the quantum system evolves differently based on the number of active information processes. The expectation of the Hamiltonian at a given state is the solution of a second-order nonlinear differential equation determined by one of the possible regimes that the quantum system belongs to. It is shown that the collapse rate is a submartingale with positive jumps and the Shannon entropy process is a supermartingale with expected negative jumps when passing to higher-order probability spaces. The framework is extended to the case when the Hamiltonian is modeled as a function of a set of commutative operators, where each operator is associated with a different piecewise enlarged filtration.

  13. Plasma Kisspeptin Levels in Newborn Infants with Breast Enlargement

    PubMed Central

    Kaya, Avni; Orbak, Zerrin; Polat, Harun; Çayır, Atilla; Erdil, Abdullah; Döneray, Hakan

    2015-01-01

    Objective: Kisspeptin levels have been reported in children with premature thelarche, precocious puberty and adolescent gynecomastia, but there are no reports on kisspeptin levels in the neonatal period. This study aimed to investigate plasma kisspeptin hormone levels in newborns with and without breast enlargement. Methods: Plasma kisspeptin levels and other related biochemical variables were investigated in this prospective study conducted on 40 (20 girls and 20 boys) newborn infants with breast enlargement and on 40 healthy control infants (20 girls and 20 boys). Two-milliliter venous blood samples were taken in hemogram tubes with K2EDTA. Kisspeptin assays were performed using the enzyme-immunoassay method. Results: Mean plasma kisspeptin levels were 0.6±0.2 ng/mL in the study group and 0.5±0.2 ng/mL in the control group. Plasma kisspeptin concentrations were significantly higher in the study group (p=0.039) and also showed a correlation with serum prolactin levels (p=0.006). Significant correlations were also determined between plasma kisspeptin and luteinizing hormone concentrations (p=0.05, r=0.312). Conclusion: The findings of this study suggest that plasma kisspeptin and serum prolactin levels may be involved in the physiopathology of breast enlargement in newborns. PMID:26831552

  14. Dissociable Temporo-Parietal Memory Networks Revealed by Functional Connectivity during Episodic Retrieval

    PubMed Central

    Hirose, Satoshi; Kimura, Hiroko M.; Jimura, Koji; Kunimatsu, Akira; Abe, Osamu; Ohtomo, Kuni; Miyashita, Yasushi; Konishi, Seiki

    2013-01-01

    Episodic memory retrieval most often recruits multiple separate processes that are thought to involve different temporal regions. Previous studies suggest dissociable regions in the left lateral parietal cortex that are associated with the retrieval processes. Moreover, studies using resting-state functional connectivity (RSFC) have provided evidence for the temporo-parietal memory networks that may support the retrieval processes. In this functional MRI study, we tested functional significance of the memory networks by examining functional connectivity of brain activity during episodic retrieval in the temporal and parietal regions of the memory networks. Recency judgments, judgments of the temporal order of past events, can be achieved by at least two retrieval processes, relational and item-based. Neuroimaging results revealed several temporal and parietal activations associated with relational/item-based recency judgments. Significant RSFC was observed between one parahippocampal region and one left lateral parietal region associated with relational recency judgments, and between four lateral temporal regions and another left lateral parietal region associated with item-based recency judgments. Functional connectivity during task was found to be significant between the parahippocampal region and the parietal region in the RSFC network associated with relational recency judgments. However, out of the four tempo-parietal RSFC networks associated with item-based recency judgments, only one of them (between the left posterior lateral temporal region and the left lateral parietal region) showed significant functional connectivity during task. These results highlight the contrasting roles of the parahippocampal and the lateral temporal regions in recency judgments, and suggest that only a part of the tempo-parietal RSFC networks are recruited to support particular retrieval processes. PMID:24009657

  15. Intrinsic connections and architectonics of posterior parietal cortex in the rhesus monkey

    SciTech Connect

    Pandya, D.N.; Seltzer, B.

    1982-01-10

    By means of autoradiographic and ablation-degeneration techniques, the intrinsic cortical connections of the posterior parietal cortex in the rhesus monkey were traced and correlated with a reappraisal of cerebral architectonics. Two major rostral-to-caudal connectional sequences exist. One begins in the dorsal postcentral gyrus (area 2) and proceeds, through architectonic divisions of the superior parietal lobule (areas PE and PEc), to a cortical region on the medial surface of the parietal lobe (area PGm). This area has architectonic features similar to those of the caudal inferior parietal lobule (area PG). The second sequence begins in the ventral post/central gyrus (area 2) and passes through the rostral inferior parietal lobule (areas PG and PFG) to reach the caudal inferior parietal lobule (area PG). Both the superior parietal lobule and the rostral inferior parietal lobule also send projections to various other zones located in the parietal opercular region, the intraparietal sulcus, and the caudalmost portion of the cingulate sulcus. Areas PGm and PG, on the other hand, project to each other, to the cingulate region, to the caudalmost portion of the superior temporal gyrus, and to the upper bank of the superior temporal sulcus. Finally, a reciprocal sequence of connections, directed from caudal to rostral, links together many of the above-mentioned parietal zones. With regard to the laminar pattern of termination, the rostral-to-caudal connections are primarily distributed in the form of cortical ''columns'' while the caudal-to-rostral connections are found mainly over the first cortical cell layer.

  16. Right Ventricular Enlargement In Utero: Is It Coarctation?

    PubMed

    Sivanandam, Shanthi; Nyholm, Jessica; Wey, Andrew; Bass, John L

    2015-10-01

    Antenatal diagnosis of right heart enlargement has a wide spectrum of differential diagnosis from maternal, placental and fetal causes, and outcomes of all are not known. Coarctation of the aorta is in the differential diagnosis of right heart enlargement. In our study, we focused to measure multiple cardiac dimensions in fetuses with right heart enlargement to identify the fetus with coarctation of the aorta utilizing echocardiographic measurements. Ten cardiovascular dimensions were measured from fetal studies between 20- and 34-week gestation, and six were measured on postnatal echocardiograms. Z-scores for the cardiac dimensions were calculated, and each variable for fetuses and infants was tested using a two-sample t test between patients with and without coarctation. We excluded fetuses with TAPVR, Shone complex, interrupted aortic arch, Ebstein anomaly or HLHS. Of the 31 fetuses with in utero right heart enlargement, 11 had coarctation postnatally and 20 did not have coarctation. We compared the fetal and newborn cardiac dimensions between the groups. The mean fetal carotid-subclavian index (CS Index) was 0.7 mm with coarctation compared with 1.1 mm without coarctation (p < 0.0001). The mean difference in diameter z-scores for fetal aortic isthmus (p < 0.0001), mitral valve (<0.001) and aortic valve (p < 0.009) was also significantly different. Similar significant differences were noted postnatally in the diameters of the cardiac dimensions between the coarctation and no-coarctation group: CS index (p < 0.0001), aortic isthmus (p < 0.0002) and aortic valve annulus (p < 0.007). A spectrum of diagnoses was found postnatally in fetuses with right heart enlargement, including a normal heart. The likelihood of identifying fetuses with coarctation of the aorta and planning for postnatal management can be refined by noninvasive screening measurements. A smaller CS index and smaller diameters of the aortic isthmus, mitral valve and aortic valve were significantly

  17. Short-term memory deficit after focal parietal damage.

    PubMed

    Markowitsch, H J; Kalbe, E; Kessler, J; von Stockhausen, H M; Ghaemi, M; Heiss, W D

    1999-12-01

    The neuropsychological symptomatology is reported for a 44-year-old patient of normal intelligence, EE, after removal of a circumscribed left hemispheric tumor the major part of which was located in the angular gyrus and in the subcortical white matter. EE had a distinct and persistent short-term memory impairment together with an equally severe impairment in transcoding numbers. On the other hand, his performance was flawless in calculation tasks and in all other tests involving number processing. Impairments in language tests could be attributed to his short-term memory deficit, which furthermore was characterized by a strong primacy effect in the absence of a recency effect. His graphomotoric output was temporarily inhibited. The patient, with a strong left-sided dominance, manifested a bi-hemispherical activation of the Broca and Wernicke regions in a positron-emission-tomographic investigation when required to produce verbs which he was to derive from nouns. The findings in EE suggest that unilateral and restricted lateral parietal damage can result in a profound short-term memory deficit together with a transcoding deficit for stimuli extending over only a few digits or syllables in the absence of any symptoms of the Gerstmann syndrome.

  18. Spatial invariance of visual receptive fields in parietal cortex neurons.

    PubMed

    Duhamel, J R; Bremmer, F; Ben Hamed, S; Graf, W

    1997-10-23

    Spatial information is conveyed to the primary visual cortex in retinal coordinates. Movement trajectory programming, however, requires a transformation from this sensory frame of reference into a frame appropriate for the selected part of the body, such as the eye, head or arms. To achieve this transformation, visual information must be combined with information from other sources: for instance, the location of an object of interest can be defined with respect to the observer's head if the position of the eyes in the orbit is known and is added to the object's retinal coordinates. Here we show that in a subdivision of the monkey parietal lobe, the ventral intraparietal area (VIP), the activity of visual neurons is modulated by eye-position signals, as in many other areas of the cortical visual system. We find that individual receptive fields of a population of VIP neurons are organized along a continuum, from eye to head coordinates. In the latter case, neurons encode the azimuth and/or elevation of a visual stimulus, independently of the direction in which the eyes are looking, thus representing spatial locations explicitly in at least a head-centred frame of reference. PMID:9349815

  19. Contralesional neglect in monkeys with small unilateral parietal cortical ablations.

    PubMed

    Marshall, J W B; Baker, H F; Ridley, R M

    2002-10-17

    Transient contralesional spatial neglect, in addition to motor impairment in the contralesional arm, is sometimes seen in patients following cerebral infarction in the right hemisphere and is seen following experimental occlusion of the right middle cerebral artery in primates. To test whether contralesional visuospatial neglect arises from a disruption of the forward flow of information from the striate cortex through the dorsal territory of the middle cerebral artery, we made a small strip suction ablation in the right parietal cortex from the medial edge of the dorsal cortical surface to the posterior ventral edge of the superior temporal gyrus in marmoset monkeys. These monkeys did not exhibit a motor impairment, or misreaching, with the contralesional arm. When they were unrestrained and free to use either arm, they were impaired at finding rewards in their contralesional space and in choosing the nearer of two rewards hidden in ipsilesional space (i.e. they had an ultra-ipsilesional bias in ipsilesional space). Comparison of performance under four conditions in a task in which the monkeys were constrained to reach into each hemispace with each arm separately indicated that they were impaired at reaching into contralesional, but not ipsilesional, space with either arm but they did not exhibit any impairment confined to the contralesional arm. These impairments in contralesional space were transient suggesting that the monkeys were able to re-align their egocentric spatial coordinates to obviate these deficits.

  20. TMS of posterior parietal cortex disrupts visual tactile multisensory integration

    PubMed Central

    Pasalar, Siavash; Ro, Tony; Beauchamp, Michael S.

    2010-01-01

    Functional neuroimaging studies have implicated a number of brain regions, especially the posterior parietal cortex (PPC), as being potentially important for visual–tactile multisensory integration. However, neuroimaging studies are correlational and do not prove the necessity of a region for the behavioral improvements that are the hallmark of multisensory integration. To remedy this knowledge gap, we interrupted activity in the PPC, near the junction of the anterior intraparietal sulcus and the postcentral sulcus, using MRI-guided transcranial magnetic stimulation (TMS) while subjects localized touches delivered to different fingers. As the touches were delivered, subjects viewed a congruent touch video, an incongruent touch video, or no video. Without TMS, a strong effect of multisensory integration was observed, with significantly better behavioral performance for discrimination of congruent multisensory touch than for unisensory touch alone. Incongruent multisensory touch produced a smaller improvement in behavioral performance. TMS of the PPC eliminated the behavioral advantage of both congruent and incongruent multisensory stimuli, reducing performance to unisensory levels. These results demonstrate a causal role for the PPC in visual–tactile multisensory integration. Taken together with converging evidence from other studies, these results support a model in which the PPC contains a map of space around the hand that receives input from both the visual and somatosensory modalities. Activity in this map is likely to be the neural substrate for visual–tactile multisensory integration. PMID:20584182

  1. Time Adaptation Shows Duration Selectivity in the Human Parietal Cortex.

    PubMed

    Hayashi, Masamichi J; Ditye, Thomas; Harada, Tokiko; Hashiguchi, Maho; Sadato, Norihiro; Carlson, Synnöve; Walsh, Vincent; Kanai, Ryota

    2015-01-01

    Although psychological and computational models of time estimation have postulated the existence of neural representations tuned for specific durations, empirical evidence of this notion has been lacking. Here, using a functional magnetic resonance imaging (fMRI) adaptation paradigm, we show that the inferior parietal lobule (IPL) (corresponding to the supramarginal gyrus) exhibited reduction in neural activity due to adaptation when a visual stimulus of the same duration was repeatedly presented. Adaptation was strongest when stimuli of identical durations were repeated, and it gradually decreased as the difference between the reference and test durations increased. This tuning property generalized across a broad range of durations, indicating the presence of general time-representation mechanisms in the IPL. Furthermore, adaptation was observed irrespective of the subject's attention to time. Repetition of a nontemporal aspect of the stimulus (i.e., shape) did not produce neural adaptation in the IPL. These results provide neural evidence for duration-tuned representations in the human brain. PMID:26378440

  2. Time Adaptation Shows Duration Selectivity in the Human Parietal Cortex

    PubMed Central

    Hayashi, Masamichi J.; Ditye, Thomas; Harada, Tokiko; Hashiguchi, Maho; Sadato, Norihiro; Carlson, Synnöve; Walsh, Vincent; Kanai, Ryota

    2015-01-01

    Although psychological and computational models of time estimation have postulated the existence of neural representations tuned for specific durations, empirical evidence of this notion has been lacking. Here, using a functional magnetic resonance imaging (fMRI) adaptation paradigm, we show that the inferior parietal lobule (IPL) (corresponding to the supramarginal gyrus) exhibited reduction in neural activity due to adaptation when a visual stimulus of the same duration was repeatedly presented. Adaptation was strongest when stimuli of identical durations were repeated, and it gradually decreased as the difference between the reference and test durations increased. This tuning property generalized across a broad range of durations, indicating the presence of general time-representation mechanisms in the IPL. Furthermore, adaptation was observed irrespective of the subject’s attention to time. Repetition of a nontemporal aspect of the stimulus (i.e., shape) did not produce neural adaptation in the IPL. These results provide neural evidence for duration-tuned representations in the human brain. PMID:26378440

  3. Beyond natural numbers: negative number representation in parietal cortex.

    PubMed

    Blair, Kristen P; Rosenberg-Lee, Miriam; Tsang, Jessica M; Schwartz, Daniel L; Menon, Vinod

    2012-01-01

    Unlike natural numbers, negative numbers do not have natural physical referents. How does the brain represent such abstract mathematical concepts? Two competing hypotheses regarding representational systems for negative numbers are a rule-based model, in which symbolic rules are applied to negative numbers to translate them into positive numbers when assessing magnitudes, and an expanded magnitude model, in which negative numbers have a distinct magnitude representation. Using an event-related functional magnetic resonance imaging design, we examined brain responses in 22 adults while they performed magnitude comparisons of negative and positive numbers that were quantitatively near (difference <4) or far apart (difference >6). Reaction times (RTs) for negative numbers were slower than positive numbers, and both showed a distance effect whereby near pairs took longer to compare. A network of parietal, frontal, and occipital regions were differentially engaged by negative numbers. Specifically, compared to positive numbers, negative number processing resulted in greater activation bilaterally in intraparietal sulcus (IPS), middle frontal gyrus, and inferior lateral occipital cortex. Representational similarity analysis revealed that neural responses in the IPS were more differentiated among positive numbers than among negative numbers, and greater differentiation among negative numbers was associated with faster RTs. Our findings indicate that despite negative numbers engaging the IPS more strongly, the underlying neural representation are less distinct than that of positive numbers. We discuss our findings in the context of the two theoretical models of negative number processing and demonstrate how multivariate approaches can provide novel insights into abstract number representation.

  4. Cortical connectivity maps reveal anatomically distinct areas in the parietal cortex of the rat

    PubMed Central

    Wilber, Aaron A.; Clark, Benjamin J.; Demecha, Alexis J.; Mesina, Lilia; Vos, Jessica M.; McNaughton, Bruce L.

    2015-01-01

    A central feature of theories of spatial navigation involves the representation of spatial relationships between objects in complex environments. The parietal cortex has long been linked to the processing of spatial visual information and recent evidence from single unit recording in rodents suggests a role for this region in encoding egocentric and world-centered frames. The rat parietal cortex can be subdivided into four distinct rostral-caudal and medial-lateral regions, which includes a zone previously characterized as secondary visual cortex. At present, very little is known regarding the relative connectivity of these parietal subdivisions. Thus, we set out to map the connectivity of the entire anterior-posterior and medial-lateral span of this region. To do this we used anterograde and retrograde tracers in conjunction with open source neuronal segmentation and tracer detection tools to generate whole brain connectivity maps of parietal inputs and outputs. Our present results show that inputs to the parietal cortex varied significantly along the medial-lateral, but not the rostral-caudal axis. Specifically, retrosplenial connectivity is greater medially, but connectivity with visual cortex, though generally sparse, is more significant laterally. Finally, based on connection density, the connectivity between parietal cortex and hippocampus is indirect and likely achieved largely via dysgranular retrosplenial cortex. Thus, similar to primates, the parietal cortex of rats exhibits a difference in connectivity along the medial-lateral axis, which may represent functionally distinct areas. PMID:25601828

  5. Combined frontal and parietal P300 amplitudes indicate compensated cognitive processing across the lifespan

    PubMed Central

    van Dinteren, Rik; Arns, Martijn; Jongsma, Marijtje L. A.; Kessels, Roy P. C.

    2014-01-01

    In the present study the frontal and parietal P300, elicited in an auditory oddball paradigm were investigated in a large sample of healthy participants (N = 1572), aged 6–87. According to the concepts of the compensation-related utilization of neural circuits hypothesis (CRUNCH) it was hypothesized that the developmental trajectories of the frontal P300 would reach a maximum in amplitude at an older age than the amplitude of the parietal P300 amplitude. In addition, the amplitude of the frontal P300 was expected to increase with aging in adulthood in contrast to a decline in amplitude of the parietal P300 amplitude. Using curve-fitting methods, a comparison was made between the developmental trajectories of the amplitudes of the frontal and parietal P300. It was found that the developmental trajectories of frontal and parietal P300 amplitudes differed significantly across the lifespan. During adulthood, the amplitude of the parietal P300 declines with age, whereas both the frontal P300 amplitude and behavioral performance remain unaffected. A lifespan trajectory of combined frontal and parietal P300 amplitudes was found to closely resemble the lifespan trajectory of behavioral performance. Our results can be understood within the concepts of CRUNCH. That is, to compensate for declining neural resources, older participants recruit additional neural resources of prefrontal origin and consequently preserve a stable behavioral performance. Though, a direct relation between amplitude of the frontal P300 and compensatory mechanisms cannot yet be claimed. PMID:25386141

  6. Influence of monkey dorsolateral prefrontal and posterior parietal activity on behavioral choice during attention tasks

    PubMed Central

    Katsuki, Fumi; Saito, Mizuki; Constantinidis, Christos

    2014-01-01

    The dorsolateral prefrontal and the posterior parietal cortex have both been implicated in the guidance of visual attention. Traditionally, posterior parietal cortex has been thought to guide visual bottom-up attention, whereas prefrontal cortex to bias attention through top-down information. More recent studies suggest a parallel time course of activation of the two areas in bottom-up attention tasks, suggesting a common involvement, though these results do not necessarily imply identical roles, either. To address the specific roles of the two areas, we examined the influence of neuronal activity recorded from the prefrontal and parietal cortex of monkeys as they performed attention tasks based on choice probability and correlation between reaction time and neuronal activity. The results revealed that posterior parietal but not dorsolateral prefrontal activity correlated with behavioral choice during the fixation period, prior to the appearance of the stimulus, resembling a bias factor. This preferential influence of posterior parietal activity on behavior was transient, so that dorsolateral prefrontal activity predicted choice after the appearance of the stimulus. Additionally, reaction time was better predicted by posterior parietal activity. These findings confirm an involvement of both dorsolateral prefrontal and posterior parietal cortex in the bottom-up guidance of visual attention but indicate different roles of the two areas in the guidance of attention and a dynamic time course of their effects, influencing behavior at different stages of the task. PMID:24964224

  7. Diagnostic dilemmas in enlarged and diffusely hemorrhagic adrenal glands.

    PubMed

    Diolombi, Mairo L; Khani, Francesca; Epstein, Jonathan I

    2016-07-01

    We have noted an increasing number of cases of enlarged adrenal glands where the underlying diagnosis was masked by a diffusely hemorrhagic process. We identified from our database 59 cases (32 consults, 27 routine) of adrenal glands with diffuse (>25%) hemorrhage received between 2000 and 2014. Fifty-three adrenalectomies and 6 biopsies were identified. The diagnoses after central review were 41 adrenocortical adenomas, 1 nodular adrenocortical hyperplasia with associated myelolipoma, 1 benign adrenocortical cyst, and 10 nonneoplastic adrenal glands with hemorrhage. A definitive diagnosis for the 6 biopsies was precluded by the sample size. The adrenocortical adenomas (size, 1-13 cm; 25%-95% hemorrhage) showed clear cell change in the neoplastic area (10%-80% of the tumor), 19 showed focal calcification (1 with ossification), 11 showed areas of papillary endothelial hyperplasia, 10 showed scattered lymphoplasmacytic inflammation, 6 showed benign cortical tissue extending beyond the adrenal capsule into soft tissue, 1 showed necrosis in the form of ghost cells, 2 showed lipomatous change, and 6 were associated with incidental benign lesions (1 cortical cyst, 1 schwannoma, and 4 myelolipomas). Twenty-four of the adrenocortical adenomas were consults where the referring pathologist had trouble classifying the lesion. Of the 10 nonneoplastic adrenals (4.5-22 cm; 40%-80% hemorrhage), 2 were consults. In summary, pathologists have difficulties recognizing adrenocortical adenomas in the setting of a massively enlarged and hemorrhagic adrenal gland. Although there is a correlation between adrenocortical malignancy and size, hemorrhage into nonmalignant adrenal glands can result in markedly enlarged adrenals.

  8. Scalable screen-size enlargement by multi-channel viewing-zone scanning holography.

    PubMed

    Takaki, Yasuhiro; Nakaoka, Mitsuki

    2016-08-01

    Viewing-zone scanning holographic displays can enlarge both the screen size and the viewing zone. However, limitations exist in the screen size enlargement process even if the viewing zone is effectively enlarged. This study proposes a multi-channel viewing-zone scanning holographic display comprising multiple projection systems and a planar scanner to enable the scalable enlargement of the screen size. Each projection system produces an enlarged image of the screen of a MEMS spatial light modulator. The multiple enlarged images produced by the multiple projection systems are seamlessly tiled on the planar scanner. This screen size enlargement process reduces the viewing zones of the projection systems, which are horizontally scanned by the planar scanner comprising a rotating off-axis lens and a vertical diffuser to enlarge the viewing zone. A screen size of 7.4 in. and a viewing-zone angle of 43.0° are demonstrated. PMID:27505840

  9. Novel Annular and Subvalvular Enlargement in Congenital Mitral Valve Replacement.

    PubMed

    Carroll, Nels D; Beers, Kevin M; Maldonado, Elaine M; Calhoon, John H; Husain, S Adil

    2016-09-01

    Reparative procedures are not always feasible in congenitally abnormal mitral valves. Mechanical prosthesis has been accepted as the choice for valve replacement in the pediatric population. This report describes a case of congenital mitral valve disease requiring mitral valve replacement. The infant's mitral valve annulus was not amenable to placement of the smallest available mechanical prosthesis. The approach used here for annular and subvalvular enlargement facilitated implantation of a larger prosthesis for congenital mitral valve replacement. Five-year outcomes in a single patient may indicate broader applicability and avoidance of patient-prosthesis mismatch.

  10. Small lymphocytic lymphoma involving an enlarging complex renal cyst.

    PubMed

    Iczkowski, Kenneth A; Gapin, Tracy B; Wajsman, Zev

    2005-01-01

    A 47-year-old white man presented for evaluation of a complex right renal mass. He had a history of human immunodeficiency virus. Cervical lymph node biopsy had revealed small lymphocytic lymphoma. Computed tomographic scan disclosed diffuse mesenteric and retroperitoneal adenopathy consistent with chronic lymphocytic leukemia, as well as a 4.5-cm complex cystic right renal mass, which 17 months later enlarged to 6.2 cm. The mass resembled multiloculated cystic nephroma. Partial nephrectomy revealed infiltration of the cyst wall by small lymphocytic lymphoma. To our knowledge, this is the first reported case of lymphoma arising in or colonizing a renal cyst.

  11. Distinct relationships of parietal and prefrontal cortices to evidence accumulation

    PubMed Central

    Hanks, Timothy; Kopec, Charles D.; Brunton, Bingni W.; Duan, Chunyu A.; Erlich, Jeffrey C.; Brody, Carlos D.

    2014-01-01

    Gradual accumulation of evidence is thought to be fundamental for decision-making, and its neural correlates have been found in multiple brain regions1–8. Here we develop a generalizable method to measure tuning curves that specify the relationship between neural responses and mentally-accumulated evidence, and apply it to distinguish the encoding of decision variables in posterior parietal cortex (PPC) and prefrontal cortex (frontal orienting fields, FOF). We recorded the firing rates of neurons in PPC and FOF from rats performing a perceptual decision-making task. Classical analyses uncovered correlates of accumulating evidence, similar to previous observations in primates and also similar across the two regions. However, tuning curve assays revealed that while the PPC encodes a graded value of the accumulating evidence, the FOF has a more categorical encoding that indicates, throughout the trial, the decision provisionally favored by the evidence accumulated so far. Contrary to current views3,5,7–9, this suggests that premotor activity in frontal cortex does not play a role in the accumulation process, but instead has a more categorical function, such as transforming accumulated evidence into a discrete choice. To causally probe the role of FOF activity, we optogenetically silenced it during different timepoints of the trial. Consistent with a role in committing to a categorical choice at the end of the evidence accumulation process, but not consistent with a role during the accumulation itself, a behavioral effect was observed only when FOF silencing occurred at the end of the perceptual stimulus. Our results place important constraints on the circuit logic of brain regions involved in decision-making. PMID:25600270

  12. A frontal but not parietal neural correlate of auditory consciousness.

    PubMed

    Brancucci, Alfredo; Lugli, Victor; Perrucci, Mauro Gianni; Del Gratta, Cosimo; Tommasi, Luca

    2016-01-01

    Hemodynamic correlates of consciousness were investigated in humans during the presentation of a dichotic sequence inducing illusory auditory percepts with features analogous to visual multistability. The sequence consisted of a variation of the original stimulation eliciting the Deutsch's octave illusion, created to maintain a stable illusory percept long enough to allow the detection of the underlying hemodynamic activity using functional magnetic resonance imaging (fMRI). Two specular 500 ms dichotic stimuli (400 and 800 Hz) presented in alternation by means of earphones cause an illusory segregation of pitch and ear of origin which can yield up to four different auditory percepts per dichotic stimulus. Such percepts are maintained stable when one of the two dichotic stimuli is presented repeatedly for 6 s, immediately after the alternation. We observed hemodynamic activity specifically accompanying conscious experience of pitch in a bilateral network including the superior frontal gyrus (SFG, BA9 and BA10), medial frontal gyrus (BA6 and BA9), insula (BA13), and posterior lateral nucleus of the thalamus. Conscious experience of side (ear of origin) was instead specifically accompanied by bilateral activity in the MFG (BA6), STG (BA41), parahippocampal gyrus (BA28), and insula (BA13). These results suggest that the neural substrate of auditory consciousness, differently from that of visual consciousness, may rest upon a fronto-temporal rather than upon a fronto-parietal network. Moreover, they indicate that the neural correlates of consciousness depend on the specific features of the stimulus and suggest the SFG-MFG and the insula as important cortical nodes for auditory conscious experience.

  13. 47 CFR 1.229 - Motions to enlarge, change, or delete issues.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Motions to enlarge, change, or delete issues. 1.229 Section 1.229 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND PROCEDURE Hearing Proceedings Participants and Issues § 1.229 Motions to enlarge, change, or delete issues. (a) A motion to enlarge, change or delete...

  14. Enlargement of the apical gap after laser root resection

    NASA Astrophysics Data System (ADS)

    Mello, Guilherme P. S.; Paradella, Thais C.; Munin, Egberto; Mello, Jose B.; Pacheco, Marcos T. T.

    2000-11-01

    An apical filling material should establish, as perfect as possible, the hermetic sealing of an apical cavity. However, a gap is formed between the filling material (gutta-percha) and the root canal wall. The egress of irritants into the root canal system to the periapical tissues is considered the principal cause of fails in apicoectomy and retro-filling, being assumed that irritants penetrate mainly through the gap located between the gutta-percha and the dentin. In this paper, we report the observation of an enlargement of the apical gap, after laser apicoectomy, comparing to conventional apicoectomy. The samples were divided into groups, and the conventional apicoectomy group, together with the Er:YAG laser group (400 mJ/10 Hz) produced both similar results, being the gap unaltered. On the other hand, the samples that were irradiated with the Er:YAG laser, followed by Nd:YAG laser irradiation (1.5 W/10 Hz) presented a larger gap, conclusions that were drawn from Scanning Electronic Microscope analysis. The enlargement of the gap was due to the fusion of the dentin on the border, close to the gutta-percha. This pronounced behavior might have been caused by the surface discontinuity, imposing a non-homogeneous condition, in relation to heat propagation, existing many clinical applications of these observations.

  15. Cerebral ventricular enlargement in subtypes of chronic schizophrenia.

    PubMed

    Nasrallah, H A; Jacoby, C G; McCalley-Whitters, M; Kuperman, S

    1982-07-01

    A computed tomographic study of the brain in 55 young men with chronic schizophrenia and 27 age- and sex-matched control subjects showed a significantly higher ventricle-brain ratio (VBR) in the patients with chronic schizophrenia. Using the Tsuang-Winokur criteria, the sample was classified into paranoid and nonparanoid-hebephrenic subtypes. Nonparanoid patients who did not fulfill the criteria for hebephrenia were grouped as a nonparanoid-undifferentiated subtype. All three groups of subtypes had a significantly higher mean VBR than control subjects. Among the schizophrenia subtypes, the paranoid and nonparanoid-hebephrenic groups were not different, and both had a significantly larger mean VBR than the nonparanoid-undifferentiated group. The results suggest that although the extent of ventricular enlargement varies among schizophrenia subtypes, they all show a significant enlargement compared with the control group. Also, in contrast with previous reports linking a high VBR with negative symptoms, poor prognosis, and impaired cognition, the data in this study show the largest mean VBR in the paranoid patients who generally have a good premorbid history, positive symptoms, less impaired cognition, and relatively better prognosis.

  16. Bone tunnel enlargement on anterior cruciate ligament reconstruction

    PubMed Central

    Leonardi, Adriano Barros de Aguiar; Duarte, Aires; Severino, Nilson Roberto

    2014-01-01

    Objective: To assess the presence of tibial bone tunnel enlargement after surgical reconstruction of the anterior cruciate ligament using quadruple graft of the flexor tendons and correlate the functional results in their presence. Methods: The studied lasted six months and included 25 patients, with ages ranging from 18 to 43 years old. Assessment was based on radiographs taken immediately postoperatively and at the third and sixth month of follow up in the anterior cruciate ligament reconstruction. Reconstruction of ligaments was performed with tendon grafts of the semitendinosus and gracilis muscle fixated in the femur with transverse metal screw and in the tibia with interference screws. Patients were evaluated objectively by tests ligament, graded from zero to four crosses and subjectively by the Lysholm method preoperative and after sixth month follow up. Results: Significant increase in the tunnels diameters were observed, 20.56% for radiographs in the anteroposterior view, 26.48% in profile view and 23.22% in computed tomography. Descriptive statistics showed significant improvement in subjective and objective clinical parameters. Conclusions: The bone tunnel enlargement is a phenomenon found in the first months after surgical reconstruction of the anterior cruciate ligament and it has no implications on clinical outcomes in the short term. Level of Evidence II, Prospective Study. PMID:25328430

  17. Capsule of Cryptococcus neoformans grows by enlargement of polysaccharide molecules

    PubMed Central

    Frases, Susana; Pontes, Bruno; Nimrichter, Leonardo; Viana, Nathan B.; Rodrigues, Marcio L.; Casadevall, Arturo

    2009-01-01

    The human pathogenic fungus Cryptococcus neoformans has a distinctive polysaccharide (PS) capsule that enlarges during infection. The capsule is essential for virulence, but the mechanism for capsular growth is unknown. In the present study, we used dynamic light scattering (LS) analysis of capsular PS and optical tweezers (OT) to explore the architecture of the capsule. Analysis of capsular PS from cells with small and large capsules by dynamic LS revealed a linear correlation between PS effective diameter and microscopic capsular diameter. This result implied that capsule growth was achieved by the addition of molecules with larger effective diameter, such that some molecules can span the entire diameter of the capsule. Measurement of polystyrene bead penetration of C. neoformans capsules by using OT techniques revealed that the outer regions were penetrable, but not the inner regions. Our results provide a mechanism for capsular enlargement based on the axial lengthening of PS molecules and suggest a model for the architecture of a eukaryotic microbial capsule. PMID:19164571

  18. [The parietal cell mass and acid secretion: Helicobacter pylori does not induce changes in the course of a duodenal ulcer].

    PubMed

    Testino, G; Sumberaz, A; Cornaggia, M

    1995-12-01

    Some studies have postulated that Helicobacter pylori (HP) itself might be responsible for hypergastrinemia and acid secretion in duodenal ulcer (DU). In each DU patient parietal cell mass (expressed by a parietal index) and stimulated acid secretion (expressed by maximal acid output) were evaluated. The study has been conducted grouping DU patients in relation to HP infection in antral mucosa. HP infection does not modify parietal cell mass and stimulated acid secretion. Therefore, mild chronic hypergastrinemia induced by HP infection is not sufficient to justify any increase of parietal index and acid secretion. In fact, parietal cells and acid secretion remain higher in DU subjects independently from HP infection.

  19. Fusion and Fission of Cognitive Functions in the Human Parietal Cortex

    PubMed Central

    Humphreys, Gina F.; Lambon Ralph, Matthew A.

    2015-01-01

    How is higher cognitive function organized in the human parietal cortex? A century of neuropsychology and 30 years of functional neuroimaging has implicated the parietal lobe in many different verbal and nonverbal cognitive domains. There is little clarity, however, on how these functions are organized, that is, where do these functions coalesce (implying a shared, underpinning neurocomputation) and where do they divide (indicating different underlying neural functions). Until now, there has been no multi-domain synthesis in order to reveal where there is fusion or fission of functions in the parietal cortex. This aim was achieved through a large-scale activation likelihood estimation (ALE) analysis of 386 studies (3952 activation peaks) covering 8 cognitive domains. A tripartite, domain-general neuroanatomical division and 5 principles of cognitive organization were established, and these are discussed with respect to a unified theory of parietal functional organization. PMID:25205661

  20. Cortical networks for visual reaching: physiological and anatomical organization of frontal and parietal lobe arm regions.

    PubMed

    Johnson, P B; Ferraina, S; Bianchi, L; Caminiti, R

    1996-01-01

    The functional and structural properties of the dorsolateral frontal lobe and posterior parietal proximal arm representations were studied in macaque monkeys. Physiological mapping of primary motor (MI), dorsal premotor (PMd), and posterior parietal (area 5) cortices was performed in behaving monkeys trained in an instructed-delay reaching task. The parietofrontal corticocortical connectivities of these same areas were subsequently examined anatomically by means of retrograde tracing techniques. Signal-, set-, movement-, and position-related directional neuronal activities were distributed nonuniformly within the task-related areas in both frontal and parietal cortices. Within the frontal lobe, moving caudally from PMd to the MI, the activity that signals for the visuo-spatial events leading to target localization decreased, while the activity more directly linked to movement generation increased. Physiological recordings in the superior parietal lobule revealed a gradient-like distribution of functional properties similar to that observed in the frontal lobe. Signal- and set-related activities were encountered more frequently in the intermediate and ventral part of the medial bank of the intraparietal sulcus (IPS), in area MIP. Movement-and position-related activities were distributed more uniformly within the superior parietal lobule (SPL), in both dorsal area 5 and in MIP. Frontal and parietal regions sharing similar functional properties were preferentially connected through their association pathways. As a result of this study, area MIP, and possibly areas MDP and 7m as well, emerge as the parietal nodes by which visual information may be relayed to the frontal lobe arm region. These parietal and frontal areas, along with their association connections, represent a potential cortical network for visual reaching. The architecture of this network is ideal for coding reaching as the result of a combination between visual and somatic information.

  1. Sustained activity in topographic areas of human posterior parietal cortex during memory-guided saccades

    PubMed Central

    Schluppeck, Denis; Curtis, Clayton E.; Glimcher, Paul W.; Heeger, David J.

    2006-01-01

    In a previous study we identified three cortical areas in human posterior parietal cortex that exhibited topographic responses during memory-guided saccades (V7, IPS1, and IPS2), which are candidate homologues of macaque parietal areas such as the lateral intraparietal area (LIP) and parietal reach region (PRR). Here, we show that these areas exhibit sustained delay-period activity, a critical physiological signature of areas in macaque parietal areas. By varying delay duration we disambiguated delay-period activity from sensory and motor responses. Mean time-courses in the parietal areas were well-fit by a linear model comprising 3 components representing responses to: (1) the visual target, (2) the delay period, and (3) the eye movement interval. We estimated the contributions of each component: the response amplitude during the delay period was substantially smaller (<30%) than that elicited by the transient visual target. All 3 parietal regions showed comparable delay period response amplitudes, with a trend towards larger responses from V7, to IPS1, and IPS2. Responses to the cue and during the delay period showed clear lateralization with larger responses to trials in which the target was placed in the contralateral visual field, suggesting that both these components contributed to the topography we measured. PMID:16687501

  2. Altered pain and thermal sensation in subjects with isolated parietal and insular cortical lesions

    PubMed Central

    Veldhuijzen, D.S.; Greenspan, J.D; Kim, J.H.; Lenz, F.A.

    2009-01-01

    Studies of sensory function following cortical lesions have often included lesions which multiple cortical, white matter, and thalamic structures. We now test the hypothesis that lesions anatomically constrained to particular insular and parietal structures and their subjacent white matter are associated with different patterns of sensory loss. Sensory loss was measured by quantitative sensory testing (QST), and evaluated statistically with respect to normal values. All seven subjects with insular and/or parietal lesions demonstrated thermal hypoesthesia, although the etiology of the lesions was heterogeneous. Cold and heat hypoalgesia were only found in the subject with the most extensive parietal and insular lesion, which occurred in utero. Cold allodynia occurred clinically and by thresholds in two subjects with isolated ischemic lesions of the posterior insular/ retroinsular cortex, and by thresholds in two subjects with a lesion of parietal cortex with little or no insular involvement. Central pain occurred in the two subjects with clinical allodynia secondary to isolated lesions of the posterior insular/retroinsular cortex, which spared the anterior and posterior parietal cortex. These results suggest that nonpainful cold and heat sensations are jointly mediated by parietal and insular cortical structures so that lesions anywhere in this system may diminish sensitivity. In contrast, thermal pain is more robust requiring larger cortical lesions of these same structures to produce hypoalgesia. In addition, cold allodynia can result from restricted lesions that also produce thermal hypoesthesia, but not from all such lesions. PMID:19939715

  3. Bilateral extraocular muscles enlargement from Kimura's disease of the orbit

    PubMed Central

    Gonçalves, Allan Christian Pieroni; Moritz, Rodrigo B; Aldred, Vera L.; Monteiro, Mário Luiz Ribeiro

    2016-01-01

    Kimura's disease (KD) is a rare chronic inflammatory disease of unclear etiology, characterized by subcutaneous nodules, mainly in the head and neck region, frequently associated with regional lymphadenopathy. Orbital involvement is infrequent and when it occurs, usually affects the eyelid or the lacrimal gland. We report a case of a 44-year-old man that presented with bilateral slowly progressive proptosis that was initially misdiagnosed as Graves’ Ophthalmopathy. 15 months of worsening proptosis and the development of facial and temporal swelling led to further investigation. Computed tomography and magnetic resonance imaging showed enlargement of all recti muscles and diffuse orbital infiltration. An orbital biopsy was performed and was consistent with the diagnosis of KD. Long term oral corticosteroid showed marked improvement of proptosis and facial swelling. This case serves to emphasize that KD should be included in the differential diagnosis of inflammatory diseases of the orbit, even when characterized by predominant involvement of the extraocular muscles. PMID:24088630

  4. Hemorrhage from an enlarged emphysematous bulla during commercial air travel.

    PubMed

    Chen, Chien-Wen; Perng, Wann-Cherng; Li, Min-Hui; Yan, Horng-Chin; Wu, Chin-Pyng

    2006-12-01

    Pulmonary bullae are a common late complication in patients with emphysema. Non-communicating emphysematous bullae may expand during air travel when the ambient pressure is reduced, resulting in various forms of barotrauma including pneumothorax and air embolism. We report a 62-yr-old man with emphysema who developed hemoptysis during international commercial air travel. CT scan of the chest obtained after the travel showed air-fluid level in an enlarged bulla. He underwent resection of the bulla and had a full recovery. This is a unique presentation of stretch injury of a bulla as a form of pulmonary barotrauma occurring during commercial air travel. With the most recent ruling by the Federal Aviation Administration to allow patients with advanced chronic obstructive lung disease to travel by air with their own supplemental oxygen devices, physicians need to be aware of this type of pulmonary barotrauma and properly advise such patients who are planning to travel by air.

  5. Prestimulus frontal-parietal coherence predicts auditory detection performance in rats

    PubMed Central

    Herzog, Linnea; Salehi, Kia; Bohon, Kaitlin S.

    2014-01-01

    Electrophysiology in primates has implicated long-range neural coherence as a potential mechanism for enhancing sensory detection. To test whether local synchronization and long-range neural coherence support detection performance in rats, we recorded local field potentials (LFPs) in frontal and parietal cortex while rats performed an auditory detection task. We observed significantly elevated power at multiple low frequencies (<15 Hz) preceding the target beep when the animal failed to respond to the signal (misses), in both frontal and parietal cortex. In terms of long-range coherence, we observed significantly more frontal-parietal coherence in the beta band (15–30 Hz) before the signal on misses compared with hits. This effect persisted after regressing away linear trends in the coherence values during a session, showing that the excess frontal-parietal beta coherence prior to misses cannot be explained by slow motivational changes during a session. In addition, a trend toward higher low-frequency (<15 Hz) coherence prior to miss trials compared with hits became highly significant when we rereferenced the LFPs to the mean voltage on each recording array, suggesting that the results are specific to our frontal and parietal areas. These results do not support a role for long-range frontal-parietal coherence or local synchronization in facilitating the detection of external stimuli. Rather, they extend to long-range frontal-parietal coherence previous findings that correlate local synchronization of low-frequency (<15 Hz) oscillations with inattention to external stimuli and synchronization of beta rhythms (15–30 Hz) with voluntary or involuntary prolongation of the current cognitive or motor state. PMID:24572093

  6. Reward-based decision signals in parietal cortex are partially embodied.

    PubMed

    Kubanek, Jan; Snyder, Lawrence H

    2015-03-25

    Recordings in the lateral intraparietal area (LIP) reveal that parietal cortex encodes variables related to spatial decision-making, the selection of desirable targets in space. It has been unclear whether parietal cortex is involved in spatial decision-making in general, or whether specific parietal compartments subserve decisions made using specific actions. To test this, we engaged monkeys (Macaca mulatta) in a reward-based decision task in which they selected a target based on its desirability. The animals' choice behavior in this task followed the molar matching law, and in each trial was governed by the desirability of the choice targets. Critically, animals were instructed to make the choice using one of two actions: eye movements (saccades) and arm movements (reaches). We recorded the discharge activity of neurons in area LIP and the parietal reach region (PRR) of the parietal cortex. In line with previous studies, we found that both LIP and PRR encode a reward-based decision variable, the target desirability. Crucially, the target desirability was encoded in LIP at least twice as strongly when choices were made using saccades compared with reaches. In contrast, PRR encoded target desirability only for reaches and not for saccades. These data suggest that decisions can evolve in dedicated parietal circuits in the context of specific actions. This finding supports the hypothesis of an intentional representation of developing decisions in parietal cortex. Furthermore, the close link between the cognitive (decision-related) and bodily (action-related) processes presents a neural contribution to the theories of embodied cognition. PMID:25810518

  7. Parietal Epithelial Cell Activation Marker in Early Recurrence of FSGS in the Transplant

    PubMed Central

    Fatima, Huma; Moeller, Marcus J.; Smeets, Bart; Yang, Hai-Chun; D’Agati, Vivette D.; Alpers, Charles E.

    2012-01-01

    Summary Background and objectives Podocyte loss is key in glomerulosclerosis. Activated parietal epithelial cells are proposed to contribute to pathogenesis of glomerulosclerosis and may serve as stem cells that can transition to podocytes. CD44 is a marker for activated parietal epithelial cells. This study investigated whether activated parietal epithelial cells are increased in early recurrent FSGS in transplant compared with minimal change disease. Design, setting, participants, & measurements CD44 staining in renal allograft biopsies from 12 patients with recurrent FSGS was performed and compared with native kidneys with minimal change disease or FSGS and normal control native and transplant kidneys without FSGS. CD44+ epithelial cells along Bowman’s capsule in the parietal epithelial cell location and over the glomerular tuft in the visceral epithelial cell location were assessed. Results Cases with early recurrent FSGS manifesting only foot process effacement showed significantly increased CD44+ visceral epithelial cells involving 29.0% versus 2.6% of glomeruli in minimal change disease and 0% in non-FSGS transplants. Parietal location CD44 positivity also was numerically increased in recurrent FSGS. In later transplant biopsies, glomeruli with segmental lesions had more CD44+ visceral epithelial cells than glomeruli without lesions. Conclusions Parietal epithelial cell activation marker is significantly increased in evolving FSGS versus minimal change disease, and this increase may distinguish early FSGS from minimal change disease. Whether parietal epithelial cell activation contributes to pathogenesis of sclerosis in idiopathic FSGS or is a regenerative/repair response to replace injured podocytes awaits additional study. PMID:22917699

  8. Ventral fronto-parietal contributions to the disruption of visual working memory storage.

    PubMed

    Hakun, Jonathan G; Ravizza, Susan M

    2016-01-01

    The ability to maintain information in visual working memory (VWM) in the presence of ongoing visual input allows for flexible goal-directed behavior. Previous evidence suggests that categorical overlap between visual distractors and the contents of VWM is associated with both the degree to which distractors disrupt VWM performance and activation among fronto-parietal regions of cortex. While within-category distractors have been shown to elicit a greater response in ventral fronto-parietal regions, to date, no study has linked distractor-evoked response of these regions to VWM performance costs. Here we examined the contributions of ventral fronto-parietal cortex to the disruption of VWM storage by manipulating memoranda-distractor similarity. Our results revealed that the degree of activation across cortex was graded in a manner suggesting that similarity between the contents of VWM and visual distractors influenced distractor processing. While abrupt visual onsets failed to engage ventral fronto-parietal regions during VWM maintenance, objects sharing categorical- (Related objects) and feature-overlap (Matched objects) with VWM elicited a significant response in the right TPJ and right AI. Of central relevance, the magnitude of activation in the right AI elicited by both types of distractor objects subsequently predicted costs to binding change detection accuracy. In addition, Related and Matched distractors differentially affected ventral-dorsal connectivity between the right AI and dorsal parietal regions, uniquely contributing to disruption of VWM storage. Together, our current results implicate activation of ventral fronto-parietal cortex in disruption of VWM storage, and disconnection between ventral frontal and dorsal parietal cortices as a mechanism to protect the contents of VWM.

  9. Ventral fronto-parietal contributions to the disruption of visual working memory storage.

    PubMed

    Hakun, Jonathan G; Ravizza, Susan M

    2016-01-01

    The ability to maintain information in visual working memory (VWM) in the presence of ongoing visual input allows for flexible goal-directed behavior. Previous evidence suggests that categorical overlap between visual distractors and the contents of VWM is associated with both the degree to which distractors disrupt VWM performance and activation among fronto-parietal regions of cortex. While within-category distractors have been shown to elicit a greater response in ventral fronto-parietal regions, to date, no study has linked distractor-evoked response of these regions to VWM performance costs. Here we examined the contributions of ventral fronto-parietal cortex to the disruption of VWM storage by manipulating memoranda-distractor similarity. Our results revealed that the degree of activation across cortex was graded in a manner suggesting that similarity between the contents of VWM and visual distractors influenced distractor processing. While abrupt visual onsets failed to engage ventral fronto-parietal regions during VWM maintenance, objects sharing categorical- (Related objects) and feature-overlap (Matched objects) with VWM elicited a significant response in the right TPJ and right AI. Of central relevance, the magnitude of activation in the right AI elicited by both types of distractor objects subsequently predicted costs to binding change detection accuracy. In addition, Related and Matched distractors differentially affected ventral-dorsal connectivity between the right AI and dorsal parietal regions, uniquely contributing to disruption of VWM storage. Together, our current results implicate activation of ventral fronto-parietal cortex in disruption of VWM storage, and disconnection between ventral frontal and dorsal parietal cortices as a mechanism to protect the contents of VWM. PMID:26436710

  10. Neural correlates of superior intelligence: stronger recruitment of posterior parietal cortex.

    PubMed

    Lee, Kun Ho; Choi, Yu Yong; Gray, Jeremy R; Cho, Sun Hee; Chae, Jeong-Ho; Lee, Seungheun; Kim, Kyungjin

    2006-01-15

    General intelligence (g) is a common factor in diverse cognitive abilities and a major influence on life outcomes. Neuroimaging studies in adults suggest that the lateral prefrontal and parietal cortices play a crucial role in related cognitive activities including fluid reasoning, the control of attention, and working memory. Here, we investigated the neural bases for intellectual giftedness (superior-g) in adolescents, using fMRI. The participants consisted of a superior-g group (n = 18, mean RAPM = 33.9 +/- 0.8, >99%) from the national academy for gifted adolescents and the control group (n = 18, mean RAPM = 22.8 +/- 1.6, 60%) from local high schools in Korea (mean age = 16.5 +/- 0.8). fMRI data were acquired while they performed two reasoning tasks with high and low g-loadings. In both groups, the high g-loaded tasks specifically increased regional activity in the bilateral fronto-parietal network including the lateral prefrontal, anterior cingulate, and posterior parietal cortices. However, the regional activations of the superior-g group were significantly stronger than those of the control group, especially in the posterior parietal cortex. Moreover, regression analysis revealed that activity of the superior and intraparietal cortices (BA 7/40) strongly covaried with individual differences in g (r = 0.71 to 0.81). A correlated vectors analysis implicated bilateral posterior parietal areas in g. These results suggest that superior-g may not be due to the recruitment of additional brain regions but to the functional facilitation of the fronto-parietal network particularly driven by the posterior parietal activation.

  11. Behaviorally Relevant Abstract Object Identity Representation in the Human Parietal Cortex

    PubMed Central

    Jeong, Su Keun

    2016-01-01

    The representation of object identity is fundamental to human vision. Using fMRI and multivoxel pattern analysis, here we report the representation of highly abstract object identity information in human parietal cortex. Specifically, in superior intraparietal sulcus (IPS), a region previously shown to track visual short-term memory capacity, we found object identity representations for famous faces varying freely in viewpoint, hairstyle, facial expression, and age; and for well known cars embedded in different scenes, and shown from different viewpoints and sizes. Critically, these parietal identity representations were behaviorally relevant as they closely tracked the perceived face-identity similarity obtained in a behavioral task. Meanwhile, the task-activated regions in prefrontal and parietal cortices (excluding superior IPS) did not exhibit such abstract object identity representations. Unlike previous studies, we also failed to observe identity representations in posterior ventral and lateral visual object-processing regions, likely due to the greater amount of identity abstraction demanded by our stimulus manipulation here. Our MRI slice coverage precluded us from examining identity representation in anterior temporal lobe, a likely region for the computing of identity information in the ventral region. Overall, we show that human parietal cortex, part of the dorsal visual processing pathway, is capable of holding abstract and complex visual representations that are behaviorally relevant. These results argue against a “content-poor” view of the role of parietal cortex in attention. Instead, the human parietal cortex seems to be “content rich” and capable of directly participating in goal-driven visual information representation in the brain. SIGNIFICANCE STATEMENT The representation of object identity (including faces) is fundamental to human vision and shapes how we interact with the world. Although object representation has traditionally been

  12. UNDERSTANDING THE PARIETAL LOBE SYNDROME FROM A NEUROPHYSIOLOGICAL AND EVOLUTIONARY PERSPECTIVE

    PubMed Central

    Caminiti, Roberto; Chafee, Matthew V.; Battaglia-Mayer, Alexandra; Averbeck, Bruno B.; Crowe, David A.; Georgopoulos, Apostolos P.

    2010-01-01

    In human and non-human primates parietal cortex is formed by a multiplicity of areas. For those of the Superior Parietal Lobule (SPL) there exists a certain homology between man and macaques. As a consequence, Optic Ataxia, a disturbed visual control of hand reaching, has similar features in man and monkeys. Establishing such correspondence has proven difficult for the areas of the Inferior Parietal Lobule (IPL). This difficulty depends on many factors. First, no physiological information is available in man on the dynamic properties of cells in the IPL. Second, the number of IPL areas identified in the monkey is paradoxically higher that that so far described in man, although this issue will probably be reconsidered in future years, thanks to comparative imaging studies. Third, the consequences of parietal lesions in monkeys do not always match those observed in humans. This is another paradox if one considers that, in certain cases, the functional properties of neurons in the monkeys IPL would predict the presence of behavioral skills, such as construction capacity, that however do not seem to emerge in the wild. Therefore, Constructional Apraxia, which is well characterized in man, has never been described in monkeys and apes. Finally, only certain aspects, i.e. hand Directional Hypokinesia and Gaze Apraxia (Balint's Psychic Paralysis of Gaze), of the multifaceted syndrome Hemispatial Neglect have been described in monkeys. These similarities, differences and paradoxes, among many others, make the study of the evolution and function of parietal cortex a challenging “case”. PMID:20550568

  13. Role of Medio-Dorsal Frontal and Posterior Parietal Neurons during Auditory Detection Performance in Rats

    PubMed Central

    Bohon, Kaitlin S.; Wiest, Michael C.

    2014-01-01

    To further characterize the role of frontal and parietal cortices in rat cognition, we recorded action potentials simultaneously from multiple sites in the medio-dorsal frontal cortex and posterior parietal cortex of rats while they performed a two-choice auditory detection task. We quantified neural correlates of task performance, including response movements, perception of a target tone, and the differentiation between stimuli with distinct features (different pitches or durations). A minority of units—15% in frontal cortex, 23% in parietal cortex—significantly distinguished hit trials (successful detections, response movement to the right) from correct rejection trials (correct leftward response to the absence of the target tone). Estimating the contribution of movement-related activity to these responses suggested that more than half of these units were likely signaling correct perception of the auditory target, rather than merely movement direction. In addition, we found a smaller and mostly not overlapping population of units that differentiated stimuli based on task-irrelevant details. The detection-related spiking responses we observed suggest that correlates of perception in the rat are sparsely represented among neurons in the rat's frontal-parietal network, without being concentrated preferentially in frontal or parietal areas. PMID:25479194

  14. Neural sources of visual working memory maintenance in human parietal and ventral extrastriate visual cortex.

    PubMed

    Becke, Andreas; Müller, Notger; Vellage, Anne; Schoenfeld, Mircea Ariel; Hopf, Jens-Max

    2015-04-15

    Maintaining information in visual working memory is reliably indexed by the contralateral delay activity (CDA) - a sustained modulation of the event-related potential (ERP) with a topographical maximum over posterior scalp regions contralateral to the memorized input. Based on scalp topography, it is hypothesized that the CDA reflects neural activity in the parietal cortex, but the precise cortical origin of underlying electric activity was never determined. Here we combine ERP recordings with magnetoencephalography based source localization to characterize the cortical current sources generating the CDA. Observers performed a cued delayed match to sample task where either the color or the relative position of colored dots had to be maintained in memory. A detailed source-localization analysis of the magnetic activity in the retention interval revealed that the magnetic analog of the CDA (mCDA) is generated by current sources in the parietal cortex. Importantly, we find that the mCDA also receives contribution from current sources in the ventral extrastriate cortex that display a time-course similar to the parietal sources. On the basis of the magnetic responses, forward modeling of ERP data reveals that the ventral sources have non-optimal projections and that these sources are therefore concealed in the ERP by overlapping fields with parietal projections. The present observations indicate that visual working memory maintenance, as indexed by the CDA, involves the parietal cortical regions as well as the ventral extrastriate regions, which code the sensory representation of the memorized content.

  15. Black spots concentrate oncogenic asbestos fibers in the parietal pleura. Thoracoscopic and mineralogic study.

    PubMed

    Boutin, C; Dumortier, P; Rey, F; Viallat, J R; De Vuyst, P

    1996-01-01

    Epidemiologic and pathologic data demonstrate that malignant mesothelioma occurs preferentially after exposure to long amphibole asbestos fibers. However, mineralogic studies have rarely detected such fibers in the parietal pleura. We hypothesized that the distribution of asbestos fibers in the pleura was heterogeneous and that they might concentrate in certain areas, as does coal dust in patients showing anthracotic "black spots" of the parietal pleura during thoracoscopy. We collected thoracoscopic biopsy samples from these black spots and from normal areas of the parietal pleura and lung from 14 subjects (eight with and six without asbestos exposure). Asbestos content was determined by transmission electron microscopy. In exposed subjects, mean fiber concentrations were 12.4 +/- 9.8 x 10(6) fibers/g of dry tissue in lung, 4.1 +/- 1.9 in black spots, and 0.5 +/- 0.2 in normal pleura. In unexposed patients, concentrations were 0, 0.3 +/- 0.1, and 0, respectively. Amphiboles outnumbered chrysotile in all samples. A total of 22.5% of fibers were > or = 5 microns in length in black spots. A histologic similarity of these black spots with milky spots is suggested by conventional and electron microscopy. We conclude that the distribution of asbestos fibers is heterogeneous in the parietal pleura. Indeed, the fibers concentrate in black spots, where they can reach high concentrations. These findings could explain why the parietal pleura is the target organ for mesothelioma and plaques.

  16. Frontal and parietal lobe involvement in the processing of pretence and intention.

    PubMed

    Chiavarino, Claudia; Apperly, Ian A; Humphreys, Glyn W

    2009-09-01

    We assessed whether different processes might be at play during pretence understanding by examining breakdowns of performance in participants with acquired brain damage. In Experiment 1 patients with frontal or parietal lesions and neurologically intact adults were asked to categorize videos of pretend and real actions. In Experiment 2 participants saw three types of videos: real intentional actions, real accidental actions, and pretend actions. In one session they judged whether the actions they saw were intentional or accidental, and in a second session they judged whether the actions were real or pretend. Parietal patients had particular difficulties in the identification of pretend actions, and both parietal and frontal patients were more impaired than controls in understanding the intentional nature of pretence. Analyses of individual patients' performance revealed that parietal lesions, and in particular lesions to the temporo-parietal junction, impaired the ability to discriminate pretend from real actions. However, this did not necessarily affect the discrimination of intentional from unintentional actions, which instead may be independently disrupted by damage to frontal areas. Moreover, spared ability to discriminate pretend actions from real actions, and intentional actions from accidental actions, did not grant a full conceptual understanding of the intentional nature of pretence. The implications for pretence understanding are discussed. PMID:19219753

  17. Assembly and enlargement of the primary cell wall in plants

    NASA Technical Reports Server (NTRS)

    Cosgrove, D. J.

    1997-01-01

    Growing plant cells are shaped by an extensible wall that is a complex amalgam of cellulose microfibrils bonded noncovalently to a matrix of hemicelluloses, pectins, and structural proteins. Cellulose is synthesized by complexes in the plasma membrane and is extruded as a self-assembling microfibril, whereas the matrix polymers are secreted by the Golgi apparatus and become integrated into the wall network by poorly understood mechanisms. The growing wall is under high tensile stress from cell turgor and is able to enlarge by a combination of stress relaxation and polymer creep. A pH-dependent mechanism of wall loosening, known as acid growth, is characteristic of growing walls and is mediated by a group of unusual wall proteins called expansins. Expansins appear to disrupt the noncovalent bonding of matrix hemicelluloses to the microfibril, thereby allowing the wall to yield to the mechanical forces generated by cell turgor. Other wall enzymes, such as (1-->4) beta-glucanases and pectinases, may make the wall more responsive to expansin-mediated wall creep whereas pectin methylesterases and peroxidases may alter the wall so as to make it resistant to expansin-mediated creep.

  18. Enlargement of cerebral ventricles as an early indicator of encephalomyelitis.

    PubMed

    Lepore, Stefano; Waiczies, Helmar; Hentschel, Jan; Ji, Yiyi; Skodowski, Julia; Pohlmann, Andreas; Millward, Jason M; Paul, Friedemann; Wuerfel, Jens; Niendorf, Thoralf; Waiczies, Sonia

    2013-01-01

    Inflammatory disorders of the central nervous system such as multiple sclerosis and acute disseminated encephalomyelitis involve an invasion of immune cells that ultimately leads to white matter demyelination, neurodegeneration and development of neurological symptoms. A clinical diagnosis is often made when neurodegenerative processes are already ongoing. In an attempt to seek early indicators of disease, we studied the temporal and spatial distribution of brain modifications in experimental autoimmune encephalomyelitis (EAE). In a thorough magnetic resonance imaging study performed with EAE mice, we observed significant enlargement of the ventricles prior to disease clinical manifestation and an increase in free water content within the cerebrospinal fluid as demonstrated by changes in T2 relaxation times. The increase in ventricle size was seen in the lateral, third and fourth ventricles. In some EAE mice the ventricle size started returning to normal values during disease remission. In parallel to this macroscopic phenomenon, we studied the temporal evolution of microscopic lesions commonly observed in the cerebellum also starting prior to disease onset. Our data suggest that changes in ventricle size during the early stages of brain inflammation could be an early indicator of the events preceding neurological disease and warrant further exploration in preclinical and clinical studies. PMID:23991157

  19. Hydrodynamic drag constrains head enlargement for mouthbrooding in cichlids.

    PubMed

    Van Wassenbergh, Sam; Potes, Nuno Zavattieri; Adriaens, Dominique

    2015-08-01

    Presumably as an adaptation for mouthbrooding, many cichlid fish species have evolved a prominent sexual dimorphism in the adult head. Since the head of fishes serves as a bow during locomotion, an evolutionary increase in head volume to brood more eggs can trade-off with the hydrodynamic efficiency of swimming. Here, the differences between males and females in three-dimensional shape and size of the external head surfaces and the effect thereof on drag force during locomotion was analysed for the Nile tilapia (Oreochromis niloticus), a maternal mouthbrooder. To do so, three-dimensional body surface reconstructions from laser scans and computational fluid dynamics simulations were performed. After scaling the scanned specimens to post-cranial body volume, in order to theoretically equalize propulsive power, the external volume of the head of females was 27% larger than that of males (head length + 14%; head width + 9%). These differences resulted in an approximate 15% increase in drag force. Yet, hydrodynamics imposed important constraints on the adaptation for mouthbrooding as a much more drastic drop in swimming efficiency seems avoided by mainly enlarging the head along the swimming direction.

  20. Positive T wave overshoot as a sign of ventricular enlargement.

    PubMed

    Short, D; Weir, J

    1984-03-01

    A consecutive series of 86 patients with an inverted T wave showing terminal positivity (overshoot) of a specific pattern in the resting electrocardiogram were studied. Patients with bundle branch block or electrocardiographic evidence of acute infarction and those taking digoxin or a similar drug were excluded. In 67 patients the heart was examined by echocardiography and in a further two by direct inspection. Sixty six of the 69 patients had an abnormal thickness of the left (or right) ventricle or a calculated left ventricular mass greater than 200 g. Seven of the patients examined by echocardiography had clinically pure ischaemic heart disease; all showed evidence of left ventricular enlargement. In only 39 of the 63 patients with anatomical evidence of left ventricular hypertrophy or dilatation did the electrocardiogram satisfy the standard voltage criterion of left ventricular hypertrophy. In the absence of acute infarction, bundle branch block, or digitalisation positive T wave overshoot of the pattern described is a sign of increased ventricular mass. PMID:6230092

  1. In vivo phospholipid biosynthesis in cotton cotyledons during glyoxysome enlargement

    SciTech Connect

    Chapman, K.D.; Trelease, R.N. )

    1990-05-01

    The surface are of cottonseed glyoxysomes increases about 4 fold within 36 h after imbibition. Membrane phospholipid must become available to glyoxysomes to accommodate expansion. Incubation of cotyledons (18-h-old) in 14C-choline (1 h) resulted in at least 85% recovery of 14C-phosphatidylcholine (PC) in membranes comigrating on sucrose gradients (20-59% w/w) with antimycin A-insensitive cytochrome c reductase (CCR) activity and choline- and ethanolaminephosphotransferase (CPT and EPT) activities (ER at about 24% w/w sucrose). Chase experiments with 3.4 M choline chloride for 2, 12, or 24 h led to increasing proportions of 14C-PC (36% after 24 h) recovery in mitochondria. No transfer of 14C-PC to enlarging glyoxysomes was detected. Incubations in 14C-ethanolamine yielded ER labeling after only 30 min. 14C-PE chased into mitochondria membranes more rapidly than PC (45% after 12 h), and no 14C-PE chased into glyoxysome membranes. Evidence for synthesis of 14C-PC from 14C-PE was found after 12 h chase with 1 M ethanolamine hydrochloride. Our results indicate that ER is the primary site of PC and PE synthesis in vivo and that ER contributes newly synthesized PC and PE to mitochondrial membranes but not to expanding glyoxysomal membranes. This is different from membrane biogenesis of glyoxysomes proliferating in castor bean endosperm.

  2. A nidus, crystalluria and aggregation: key ingredients for stone enlargement.

    PubMed

    Saw, N K; Rao, P N; Kavanagh, J P

    2008-02-01

    The in vitro study of calcium oxalate (CaOx) stone formation is usually based on crystallisation models but it is recognised that both healthy individuals and stone formers have crystalluria. We have established a robust in vitro stone growth model based on the principle of mixed suspension, mixed product removal system (MSMPR). Utilising this technique we studied the influence of CaOx crystallisation kinetics and the variation of calcium and oxalate concentrations on CaOx stone growth in vitro. Six stones received standard concentration of Ca (6 mM) and Ox (1.2 mM) in the medium while another six received variable concentrations of both Ca and Ox at various intervals. Stone mass was plotted against the experiment duration (typically 5-7 weeks). The stone growth was dependent on sufficient input calcium and oxalate concentrations and once triggered, stone growth could not be maintained at reduced calcium and oxalate inputs. The stone growth rate was positively correlated to the number of crystals in suspension around the stone and to the crystal nucleation rate and negatively correlated to the crystal growth rates. This leads to the conclusion that aggregation of crystals from the surrounding suspension was the dominant mechanism for stone enlargement.

  3. Gingival Enlargement in a Case of Variant Jones Syndrome: a Case Report

    PubMed Central

    DA, Roopa; Singh, Shinkhala; Gupta, Ira; Gopal, Saumiya

    2016-01-01

    Gingival enlargement can be caused by a variety of etiological factors like inflammation, drugs, and systemic diseases or can be presented as a part of a syndrome. One such syndrome is Jones Syndrome, which is associated with gingival enlargement and progressive hearing loss. We present here a case of fifteen-year-old boy with gingival enlargement, hearing loss, and generalized alveolar bone loss and diagnosed as Jones syndrome. The diagnosis was made based on history, clinical, radiographic, and histopathological findings. Gingival enlargement was surgically managed using gingivectomy and no recurrence was observed. The patient showed remarkable esthetical and functional improvement. PMID:26966711

  4. Low dose amlodipine-induced gingival enlargement: A clinical case series

    PubMed Central

    Tripathi, Amitandra Kumar; Mukherjee, Sudarshana; Saimbi, Charanjit Singh; Kumar, Vivek

    2015-01-01

    Gingival enlargement sometimes has an adverse effect of certain systemic drugs such as the use of anticonvulsants, phenytoin, antihypertensive, calcium channel blockers and immunosuppressant, cyclosporine. Amlodipine, a relatively newer calcium channel blocker drugs, exhibit adverse effect of gingival enlargement in middle to older aged adults. There are very few reports of amlodipine-induced gingival enlargement at a lower dose (5 mg). In this article, three cases of amlodipine-induced gingival enlargement in the age range of 50-65 years old hypertensive patient with a lower dose of amlodipine (5 mg). PMID:25684923

  5. Aftermath of a Crusade: World War I and the Enlarged Program of the American Library Association.

    ERIC Educational Resources Information Center

    Young, Arthur P.

    1980-01-01

    Considers the objectives, campaign strategy, ideology, and reception of the American Library Association's Enlarged Program to revitalize library services after World War I. Forty references are cited. (FM)

  6. Fractionation of parietal function in bistable perception probed with concurrent TMS-EEG.

    PubMed

    Schauer, Georg; Chang, Acer; Schwartzman, David; Rae, Charlotte L; Iriye, Heather; Seth, Anil K; Kanai, Ryota

    2016-01-01

    When visual input has conflicting interpretations, conscious perception can alternate spontaneously between these possible interpretations. This is called bistable perception. Previous neuroimaging studies have indicated the involvement of two right parietal areas in resolving perceptual ambiguity (ant-SPLr and post-SPLr). Transcranial magnetic stimulation (TMS) studies that selectively interfered with the normal function of these regions suggest that they play opposing roles in this type of perceptual switch. In the present study, we investigated this fractionation of parietal function by use of combined TMS with electroencephalography (EEG). Specifically, while participants viewed either a bistable stimulus, a replay stimulus, or resting-state fixation, we applied single pulse TMS to either location independently while simultaneously recording EEG. Combined with participant's individual structural magnetic resonance imaging (MRI) scans, this dataset allows for complex analyses of the effect of TMS on neural time series data, which may further elucidate the causal role of the parietal cortex in ambiguous perception. PMID:27529410

  7. Physiological implications of the abnormal absence of the parietal foramen in a late Permian cynodont (Therapsida)

    NASA Astrophysics Data System (ADS)

    Benoit, Julien; Abdala, Fernando; Van den Brandt, Marc J.; Manger, Paul R.; Rubidge, Bruce S.

    2015-12-01

    The third eye (pineal eye), an organ responsible for regulating exposure to sunlight in extant ectotherms, is located in an opening on the dorsal surface of the skull, the parietal foramen. The parietal foramen is absent in extant mammals but often observed in basal therapsids, the stem-group to true mammals. Here, we report the absence of the parietal foramen in a specimen of Cynosaurus suppostus, a Late Permian cynodont from South Africa (SA). Comparison with Procynosuchus delaharpeae, a contemporaneous non-mammalian cynodont from SA, demonstrates that the absence of this foramen is an abnormal condition for such a basal species. Because seasonality was marked during the Late Permian in SA, it is proposed that the third eye was functionally redundant in Cynosaurus, possibly due to the acquisition of better thermoregulation or the evolution of specialized cells in the lateral eyes to compensate for the role of the third eye.

  8. Parietal theta burst TMS: Functional fractionation observed during bistable perception not evident in attention tasks.

    PubMed

    Schauer, Georg; Kanai, Ryota; Brascamp, Jan W

    2016-02-01

    When visual input is ambiguous, perception spontaneously alternates between interpretations: bistable perception. Studies have identified two distinct sites near the right intraparietal sulcus where inhibitory transcranial magnetic stimulation (TMS) affects the frequency of occurrence of these alternations, but strikingly with opposite directions of effect for the two sites. Lesion and TMS studies on spatial and sustained attention have also indicated a parcellation of right parietal cortex, into areas serving distinct attentional functions. We used the exact TMS procedure previously employed to affect bistable perception, yet measured its effect on spatial and sustained attention tasks. Although there was a trend for TMS to affect performance, trends were consistently similar for both parietal sites, with no indication of opposite effects. We interpret this as signifying that the previously observed parietal fractionation of function regarding the perception of ambiguous stimuli is not due to TMS-induced modification of spatial or sustained attention.

  9. Effects of parietal lesions in humans on color and location priming.

    PubMed

    Marangolo, P; Di Pace, E; Rafal, R; Scabini, D

    1998-11-01

    To determine whether the parietal lobes contribute tot he selection of nonspatial features known to be processed in the ventral stream, the current study examined the effect of chronic unilateral parietal lobe lesions in humans on color and location priming. Patients and normal controls performed a go/no-go color discrimination task in which either the same color and different color pairs of stimuli (prime and probe) were projected sequentially either in the same hemifield or in opposite hemifields. Control subjects and patients both showed independent effects of color and location priming. In the patients, primes in either field produced color priming for target probes in the ipsilesional field but not for probes in the contralesional field. This observation implicates the parietal cortex in processing activated codes of stimulus attributes not only for spatial information but also for visual features processed in the ventral visual pathways.

  10. Fractionation of parietal function in bistable perception probed with concurrent TMS-EEG

    PubMed Central

    Schauer, Georg; Chang, Acer; Schwartzman, David; Rae, Charlotte L.; Iriye, Heather; Seth, Anil K.; Kanai, Ryota

    2016-01-01

    When visual input has conflicting interpretations, conscious perception can alternate spontaneously between these possible interpretations. This is called bistable perception. Previous neuroimaging studies have indicated the involvement of two right parietal areas in resolving perceptual ambiguity (ant-SPLr and post-SPLr). Transcranial magnetic stimulation (TMS) studies that selectively interfered with the normal function of these regions suggest that they play opposing roles in this type of perceptual switch. In the present study, we investigated this fractionation of parietal function by use of combined TMS with electroencephalography (EEG). Specifically, while participants viewed either a bistable stimulus, a replay stimulus, or resting-state fixation, we applied single pulse TMS to either location independently while simultaneously recording EEG. Combined with participant’s individual structural magnetic resonance imaging (MRI) scans, this dataset allows for complex analyses of the effect of TMS on neural time series data, which may further elucidate the causal role of the parietal cortex in ambiguous perception. PMID:27529410

  11. Role of the parietal associative area of the cortex for "counting" behavior in dogs.

    PubMed

    Varga, M E; Pavlova, O G; Mats, V N

    2007-10-01

    Experiments were performed on six dogs to study the effects of simultaneous and separate ablation of fields 5 and 7 of the parietal cortex on "counting" behavior. Dogs were trained to discriminate series of five sound clicks presented with variable interstimulus intervals from similar series consisting of three clicks. A food-related operant response (elevation of the right forepaw to place it on the feeder) was used to develop asymmetrical differentiation; the positive signal was a series of five clicks with variable interstimulus intervals and the negative (unreinforced) stimulus was a series of three clicks. Simultaneous bilateral ablation of fields 5 and 7 of the parietal cortex, like bilateral ablation only of field 5, produced profound impairment of differentiation lasting 2-3 months. Isolated bilateral ablation of field 7 produced no impairment of differentiation. These data led to the conclusion that field 5 of the parietal cortex is important for discriminating the numbers of sequential signals.

  12. Optimized Gamma Synchronization Enhances Functional Binding of Fronto-Parietal Cortices in Mathematically Gifted Adolescents during Deductive Reasoning

    PubMed Central

    Zhang, Li; Gan, John Q.; Wang, Haixian

    2014-01-01

    As enhanced fronto-parietal network has been suggested to support reasoning ability of math-gifted adolescents, the main goal of this EEG source analysis is to investigate the temporal binding of the gamma-band (30–60 Hz) synchronization between frontal and parietal cortices in adolescents with exceptional mathematical ability, including the functional connectivity of gamma neurocognitive network, the temporal dynamics of fronto-parietal network (phase-locking durations and network lability in time domain), and the self-organized criticality of synchronizing oscillation. Compared with the average-ability subjects, the math-gifted adolescents show a highly integrated fronto-parietal network due to distant gamma phase-locking oscillations, which is indicated by lower modularity of the global network topology, more “connector bridges” between the frontal and parietal cortices and less “connector hubs” in the sensorimotor cortex. The time domain analysis finds that, while maintaining more stable phase dynamics of the fronto-parietal coupling, the math-gifted adolescents are characterized by more extensive fronto-parietal connection reconfiguration. The results from sample fitting in the power-law model further find that the phase-locking durations in the math-gifted brain abides by a wider interval of the power-law distribution. This phase-lock distribution mechanism could represent a relatively optimized pattern for the functional binding of frontal–parietal network, which underlies stable fronto-parietal connectivity and increases flexibility of timely network reconfiguration. PMID:24966829

  13. Frontal and Parietal Cortices Show Different Spatiotemporal Dynamics across Problem-solving Stages.

    PubMed

    Tschentscher, Nadja; Hauk, Olaf

    2016-08-01

    Arithmetic problem-solving can be conceptualized as a multistage process ranging from task encoding over rule and strategy selection to step-wise task execution. Previous fMRI research suggested a frontal-parietal network involved in the execution of complex numerical and nonnumerical tasks, but evidence is lacking on the particular contributions of frontal and parietal cortices across time. In an arithmetic task paradigm, we evaluated individual participants' "retrieval" and "multistep procedural" strategies on a trial-by-trial basis and contrasted those in time-resolved analyses using combined EEG and MEG. Retrieval strategies relied on direct retrieval of arithmetic facts (e.g., 2 + 3 = 5). Procedural strategies required multiple solution steps (e.g., 12 + 23 = 12 + 20 + 3 or 23 + 10 + 2). Evoked source analyses revealed independent activation dynamics within the first second of problem-solving in brain areas previously described as one network, such as the frontal-parietal cognitive control network: The right frontal cortex showed earliest effects of strategy selection for multistep procedural strategies around 300 msec, before parietal cortex activated around 700 msec. In time-frequency source power analyses, memory retrieval and multistep procedural strategies were differentially reflected in theta, alpha, and beta frequencies: Stronger beta and alpha desynchronizations emerged for procedural strategies in right frontal, parietal, and temporal regions as function of executive demands. Arithmetic fact retrieval was reflected in right prefrontal increases in theta power. Our results demonstrate differential brain dynamics within frontal-parietal networks across the time course of a problem-solving process, and analyses of different frequency bands allowed us to disentangle cortical regions supporting the underlying memory and executive functions.

  14. Vacuolar-type H+-ATPase-mediated proton transport in the rat parietal cell.

    PubMed

    Kopic, Sascha; Wagner, Maximilian E H; Griessenauer, Christoph; Socrates, Thenral; Ritter, Markus; Geibel, John P

    2012-03-01

    The vacuolar-type H-ATPase (V-ATPase) plays an important role in the active acidification of intracellular organelles. In certain specialized cells, such as the renal intercalated cell, apical V-ATPase can also function as a proton secretion pathway. In the parietal cells of the stomach, it has been thought that acid secretion is controlled solely via the H,K-ATPase. However, recent observations suggest that functional V-ATPase is necessary for acid secretion to take place. This study aimed to investigate and characterize the role of V-ATPase in parietal cell proton transport. Individual rat gastric glands were incubated with the pH-sensitive dye (BCECF) to monitor changes in intracellular pH in real time. Parietal cell V-ATPase activity was measured by quantifying the rate of intracellular alkalinization (ΔpH/minute) following an acid load, while excluding the contribution of non-V-ATPase proton transport mechanisms through pharmacological inhibition or ion substitution. Expression of V-ATPase was confirmed by immunohistochemistry. We observed concanamycin A-sensitive V-ATPase activity in rat parietal cells following intracellular acidification and H,K-ATPase inhibition. Furthermore, V-ATPase-mediated proton transport could be abolished by inhibiting trafficking mechanisms with paclitaxel and by stimulating H,K-ATPase with acid secretagogues. Our results propose that parietal cells contain a functional V-ATPase that can be mobilized using a microtubule network. V-ATPase may function as an auxiliary acid secretion or proton-buffering pathway in parietal cells, which is inactive during H,K-ATPase activity. Our findings may have important implications for patients experiencing acid breakthrough under proton pump inhibitor therapy.

  15. Frontal and Parietal Cortices Show Different Spatiotemporal Dynamics across Problem-solving Stages.

    PubMed

    Tschentscher, Nadja; Hauk, Olaf

    2016-08-01

    Arithmetic problem-solving can be conceptualized as a multistage process ranging from task encoding over rule and strategy selection to step-wise task execution. Previous fMRI research suggested a frontal-parietal network involved in the execution of complex numerical and nonnumerical tasks, but evidence is lacking on the particular contributions of frontal and parietal cortices across time. In an arithmetic task paradigm, we evaluated individual participants' "retrieval" and "multistep procedural" strategies on a trial-by-trial basis and contrasted those in time-resolved analyses using combined EEG and MEG. Retrieval strategies relied on direct retrieval of arithmetic facts (e.g., 2 + 3 = 5). Procedural strategies required multiple solution steps (e.g., 12 + 23 = 12 + 20 + 3 or 23 + 10 + 2). Evoked source analyses revealed independent activation dynamics within the first second of problem-solving in brain areas previously described as one network, such as the frontal-parietal cognitive control network: The right frontal cortex showed earliest effects of strategy selection for multistep procedural strategies around 300 msec, before parietal cortex activated around 700 msec. In time-frequency source power analyses, memory retrieval and multistep procedural strategies were differentially reflected in theta, alpha, and beta frequencies: Stronger beta and alpha desynchronizations emerged for procedural strategies in right frontal, parietal, and temporal regions as function of executive demands. Arithmetic fact retrieval was reflected in right prefrontal increases in theta power. Our results demonstrate differential brain dynamics within frontal-parietal networks across the time course of a problem-solving process, and analyses of different frequency bands allowed us to disentangle cortical regions supporting the underlying memory and executive functions. PMID:27027542

  16. Episodic memory retrieval, parietal cortex, and the default mode network: functional and topographic analyses.

    PubMed

    Sestieri, Carlo; Corbetta, Maurizio; Romani, Gian Luca; Shulman, Gordon L

    2011-03-23

    The default mode network (DMN) is often considered a functionally homogeneous system that is broadly associated with internally directed cognition (e.g., episodic memory, theory of mind, self-evaluation). However, few studies have examined how this network interacts with other networks during putative "default" processes such as episodic memory retrieval. Using functional magnetic resonance imaging, we investigated the topography and response profile of human parietal regions inside and outside the DMN, independently defined using task-evoked deactivations and resting-state functional connectivity, during episodic memory retrieval. Memory retrieval activated posterior nodes of the DMN, particularly the angular gyrus, but also more anterior and dorsal parietal regions that were anatomically separate from the DMN. The two sets of parietal regions showed different resting-state functional connectivity and response profiles. During memory retrieval, responses in DMN regions peaked sooner than non-DMN regions, which in turn showed responses that were sustained until a final memory judgment was reached. Moreover, a parahippocampal region that showed strong resting-state connectivity with parietal DMN regions also exhibited a pattern of task-evoked activity similar to that exhibited by DMN regions. These results suggest that DMN parietal regions directly supported memory retrieval, whereas non-DMN parietal regions were more involved in postretrieval processes such as memory-based decision making. Finally, a robust functional dissociation within the DMN was observed. Whereas angular gyrus and posterior cingulate/precuneus were significantly activated during memory retrieval, an anterior DMN node in medial prefrontal cortex was strongly deactivated. This latter finding demonstrates functional heterogeneity rather than homogeneity within the DMN during episodic memory retrieval.

  17. Multimodal responses induced by cortical stimulation of the parietal lobe: a stereo-electroencephalography study.

    PubMed

    Balestrini, Simona; Francione, Stefano; Mai, Roberto; Castana, Laura; Casaceli, Giuseppe; Marino, Daniela; Provinciali, Leandro; Cardinale, Francesco; Tassi, Laura

    2015-09-01

    The functional complexity of the parietal lobe still represents a challenge for neurophysiological and functional neuroimaging studies. While the somatosensory functions of the anterior parietal cortex are well established, the posterior parietal cortex has a relevant role in processing the sensory information, including visuo-spatial perception, visual attention, visuo-motor transformations and other complex and not completely understood functions. We retrospectively analysed all the clinical manifestations induced by intracerebral bipolar electrical stimulation in 172 patients suffering from drug-resistant focal epilepsy (mean age 25.6, standard deviation 11.6; 44% females and 56% males) with at least one electrode stereotactically implanted in the parietal cortex. A total of 1186 electrical stimulations were included in the analysis, of which 88 were subsequently excluded because of eliciting pathological electric activity or inducing ictal symptomatology. In the dominant parietal lobe, clinical responses were observed for 56 (25%) of the low-frequency stimulations and for 76 (50%) of the high-frequency stimulations. In the non-dominant parietal lobe, 111 (27%) low-frequency and 176 (55%) high-frequency stimulations were associated with a clinical response. Body scheme alteration was the only clinical effect showing a lateralization, as they were evoked only in the non-dominant hemisphere. The occurrence of somatosensory sensations, motor symptoms, dysarthria and multimodal responses were significantly associated with stimulation of the postcentral gyrus (odds ratio: 5.83, P < 0.001; odds ratio: 8.77, P < 0.001; odds ratio: 5.44, P = 0.011; odds ratio: 8.33, P = 0.006; respectively). Stimulation of the intraparietal sulcus was associated with the occurrence of sensory illusions or hallucinations (odds ratio: 8.68, P < 0.001) and eyeball/eyelid movements or sensations (odds ratio: 4.35, P = 0.047). To our knowledge, this is the only currently available complete

  18. Anarchic hand with abnormal agency following right inferior parietal lobe damage: a case report.

    PubMed

    Jenkinson, Paul M; Edelstyn, Nicola M J; Preston, Catherine; Ellis, Simon J

    2015-01-01

    Anarchic hand syndrome (AHS) is characterized by goal-directed movements performed without volitional control (agency). Different AHS subtypes have been identified; however, few studies have examined the posterior subtype. We report a case of AHS following right-hemisphere parietal damage, with left-sided somatosensory and proprioceptive impairment. Agency was examined for nonanarchic (volitional) movements performed using the anarchic hand. The patient experienced abnormal agency for movements whether motor intention and visual feedback were congruent or incongruent, but not when intention was absent (passive movement). Findings suggest a general disturbance of veridical motor awareness and agency in this case of parietal AHS.

  19. Altered prefronto-striato-parietal network response to mental rotation in HIV.

    PubMed

    Schweinsburg, Brian C; Scott, J Cobb; Schweinsburg, Alecia Dager; Jacobus, Joanna; Theilmann, Rebecca J; Frank, Larry R; Weber, Erica; Grant, Igor; Woods, Steven Paul

    2012-02-01

    The present study used functional magnetic resonance imaging to examine the neural substrates of mental rotation in 11 individuals with HIV infection and 13 demographically similar HIV seronegative volunteers. Individuals with HIV showed increased brain response to mental rotation in prefrontal and posterior parietal cortices, striatum, and thalamus, with significant HIV by angle interactions emerging in the prefrontal cortex and caudate. Results indicate that HIV infection is associated with altered brain response to mental rotation in fronto-striato-parietal pathways, which may reflect compensatory strategies, recruitment of additional brain regions, and/or increased neuroenergetic demands during mental rotation needed to offset underlying HIV-associated neural injury.

  20. The Impact of Amlodipine on Gingival Enlargement After Kidney Transplantation

    PubMed Central

    Rostami, Zohreh; Einollahi, Behzad; Einollahi, Mohammad Javad; lessan, Simin

    2012-01-01

    Abstract Background: Although cyclosporine (CsA) and calcium channel blockers (CCBs) parallel to each other may provoke gingival enlargement (GE), there are few considerations about combined effects of CsA and CCBs on gingival tissues. Objectives: This study aimed to determine prevalence of GE among renal transplant recipients and to compare its occurrence in patients who received only CsA and those who were on CsA and amlodipine. Patients and Methods: We conducted a prospective randomized case-control trial including 213 renal transplant recipients between February 2010 and August 2010. They were randomly divided into two groups including control group (on continuous treatment with CsA alone; n = 112) and trial group (treated with combined CsA and amlodipine; n = 101). Buccal, lingual, and inter-proximal membranes at last 12 anterior teeth were assessed for GE and packet depth (PD) using Gingival Index of McGaw and others, and Packet Index of Turesky–Gilmore–Glickman, respectively. Results: Marked GE was observed in 26 patients (25.7%) in trial group and only in 4 individuals (3.6%) in control group (P = 0.000). In logistic regression analysis, obese (OR = 3, P = 0.04), older (OR = 2.8, P = 0.03), and female (OR = 1.3, P = 0.03) recipients as well as who received high dose amlodipine (OR = 4.4, P = 0.000) were at risk for marked GE. Conclusions: There is a strong correlation between GE, in particular marked GE, and combination therapy with CsA and amlodipine in transplant patients compared to those treated by CsA alone. We suggest CsA dose reduction may restrain this adverse effect. PMID:23573487

  1. Body-enlarging effect of royal jelly in a non-holometabolous insect species, Gryllus bimaculatus.

    PubMed

    Miyashita, Atsushi; Kizaki, Hayato; Sekimizu, Kazuhisa; Kaito, Chikara

    2016-01-01

    Honeybee royal jelly is reported to have body-enlarging effects in holometabolous insects such as the honeybee, fly and silkmoth, but its effect in non-holometabolous insect species has not yet been examined. The present study confirmed the body-enlarging effect in silkmoths fed an artificial diet instead of mulberry leaves used in the previous literature. Administration of honeybee royal jelly to silkmoth from early larval stage increased the size of female pupae and adult moths, but not larvae (at the late larval stage) or male pupae. We further examined the body-enlarging effect of royal jelly in a non-holometabolous species, the two-spotted cricket Gryllus bimaculatus, which belongs to the evolutionarily primitive group Polyneoptera. Administration of royal jelly to G. bimaculatus from its early nymph stage enlarged both males and females at the mid-nymph and adult stages. In the cricket, the body parts were uniformly enlarged in both males and females; whereas the enlarged female silkmoths had swollen abdomens. Administration of royal jelly increased the number, but not the size, of eggs loaded in the abdomen of silkmoth females. In addition, fat body cells were enlarged by royal jelly in the silkmoth, but not in the cricket. These findings suggest that the body-enlarging effect of royal jelly is common in non-holometabolous species, G. bimaculatus, but it acts in a different manner than in holometabolous species. PMID:27185266

  2. Body-enlarging effect of royal jelly in a non-holometabolous insect species, Gryllus bimaculatus

    PubMed Central

    Miyashita, Atsushi; Kizaki, Hayato; Sekimizu, Kazuhisa; Kaito, Chikara

    2016-01-01

    ABSTRACT Honeybee royal jelly is reported to have body-enlarging effects in holometabolous insects such as the honeybee, fly and silkmoth, but its effect in non-holometabolous insect species has not yet been examined. The present study confirmed the body-enlarging effect in silkmoths fed an artificial diet instead of mulberry leaves used in the previous literature. Administration of honeybee royal jelly to silkmoth from early larval stage increased the size of female pupae and adult moths, but not larvae (at the late larval stage) or male pupae. We further examined the body-enlarging effect of royal jelly in a non-holometabolous species, the two-spotted cricket Gryllus bimaculatus, which belongs to the evolutionarily primitive group Polyneoptera. Administration of royal jelly to G. bimaculatus from its early nymph stage enlarged both males and females at the mid-nymph and adult stages. In the cricket, the body parts were uniformly enlarged in both males and females; whereas the enlarged female silkmoths had swollen abdomens. Administration of royal jelly increased the number, but not the size, of eggs loaded in the abdomen of silkmoth females. In addition, fat body cells were enlarged by royal jelly in the silkmoth, but not in the cricket. These findings suggest that the body-enlarging effect of royal jelly is common in non-holometabolous species, G. bimaculatus, but it acts in a different manner than in holometabolous species. PMID:27185266

  3. Merit Pay and Job Enlargement as Reforms: Incentives, Implementation, and Teacher Response.

    ERIC Educational Resources Information Center

    Firestone, William A.

    1991-01-01

    Based on intensive case studies of two school districts, this study compared two teacher work reforms: merit pay and job enlargement. Interviews with 64 teachers and 53 administrators, supplemented by over 1,300 survey responses, indicate the efficacy of each approach and the potential advantages of job enlargement. (SLD)

  4. Body-enlarging effect of royal jelly in a non-holometabolous insect species, Gryllus bimaculatus.

    PubMed

    Miyashita, Atsushi; Kizaki, Hayato; Sekimizu, Kazuhisa; Kaito, Chikara

    2016-06-15

    Honeybee royal jelly is reported to have body-enlarging effects in holometabolous insects such as the honeybee, fly and silkmoth, but its effect in non-holometabolous insect species has not yet been examined. The present study confirmed the body-enlarging effect in silkmoths fed an artificial diet instead of mulberry leaves used in the previous literature. Administration of honeybee royal jelly to silkmoth from early larval stage increased the size of female pupae and adult moths, but not larvae (at the late larval stage) or male pupae. We further examined the body-enlarging effect of royal jelly in a non-holometabolous species, the two-spotted cricket Gryllus bimaculatus, which belongs to the evolutionarily primitive group Polyneoptera. Administration of royal jelly to G. bimaculatus from its early nymph stage enlarged both males and females at the mid-nymph and adult stages. In the cricket, the body parts were uniformly enlarged in both males and females; whereas the enlarged female silkmoths had swollen abdomens. Administration of royal jelly increased the number, but not the size, of eggs loaded in the abdomen of silkmoth females. In addition, fat body cells were enlarged by royal jelly in the silkmoth, but not in the cricket. These findings suggest that the body-enlarging effect of royal jelly is common in non-holometabolous species, G. bimaculatus, but it acts in a different manner than in holometabolous species.

  5. Idiopathic gingival enlargement associated with generalized aggressive periodontitis in a 19-year-old female

    PubMed Central

    Shetty, Arvind; Gupta, Neha; Shetty, Devanand; Kadakia, Rukshit

    2014-01-01

    Gingival enlargement, one of the manifestations of gingival and periodontal disease, is also known as gingival overgrowth. Idiopathic gingival enlargement is a rare gingival overgrowth, which is of an undetermined cause. This unknown etiology has now been linked to specific genes and idiopathic gingival enlargement is at times referred to as hereditary gingival enlargement. This condition is a benign, slow growing proliferation of gingival tissues. Aggressive periodontitis is the rapid form of periodontal disease which is characterized by extensive periodontal tissue destruction, increased host-susceptibility toward periodontal disease progress and a genetic predilection toward disease occurrence. We present a rare case of idiopathic gingival fibromatosis associated with generalized aggressive periodontitis in a young female. The patient presented with classic clinical and radiographic presentation associated with gingival enlargement and aggressive periodontitis. The diagnosis was then confirmed by histopathological and neutrophil functions tests. PMID:24872638

  6. Seeing Is Not Feeling: Posterior Parietal But Not Somatosensory Cortex Engagement During Touch Observation

    PubMed Central

    Baker, Chris I.

    2015-01-01

    Observing touch has been reported to elicit activation in human primary and secondary somatosensory cortices and is suggested to underlie our ability to interpret other's behavior and potentially empathy. However, despite these reports, there are a large number of inconsistencies in terms of the precise topography of activation, the extent of hemispheric lateralization, and what aspects of the stimulus are necessary to drive responses. To address these issues, we investigated the localization and functional properties of regions responsive to observed touch in a large group of participants (n = 40). Surprisingly, even with a lenient contrast of hand brushing versus brushing alone, we did not find any selective activation for observed touch in the hand regions of somatosensory cortex but rather in superior and inferior portions of neighboring posterior parietal cortex, predominantly in the left hemisphere. These regions in the posterior parietal cortex required the presence of both brush and hand to elicit strong responses and showed some selectivity for the form of the object or agent of touch. Furthermore, the inferior parietal region showed nonspecific tactile and motor responses, suggesting some similarity to area PFG in the monkey. Collectively, our findings challenge the automatic engagement of somatosensory cortex when observing touch, suggest mislocalization in previous studies, and instead highlight the role of posterior parietal cortex. PMID:25632124

  7. Cortical infarction of the right parietal lobe and neurogenic heart disease: A report of three cases.

    PubMed

    Li, Fang; Jia, Yujie

    2012-04-25

    Three male patients were diagnosed with new cortical infarctions of the right parietal lobe on the basis of head magnetic resonance imaging; high-intensity signals indicating lesions in the right parietal lobe were noted on diffusion-weighted images at admission. Two of them presented with left hand weakness, and one exhibited left upper limb weakness. Treatment for improving blood supply to the brain was administered. One patient died suddenly because of ventricular fibrillation 3 days after admission. The other two patients had increased troponin levels and abnormal electrocardiograms, and were diagnosed with acute myocardial infarction half a month after admission. When lesions exist in field 7 of the parietal cortex (resulting in paralysis of the contralateral hand), the sympathetic center of the posterior lateral nucleus of the hypothalamus demonstrates compensatory excitement, which easily causes tachyarrhythmia and sudden death. Our experimental findings indicate that close electrocardiograph monitoring and cerebral infarction treatment should be standard procedures to predict and help prevent heart disease in patients with cerebral infarction in the right parietal lobe and left upper limb weakness as the main complaint. PMID:25722680

  8. Parietal Lobe Volume Deficits in Adolescents with Schizophrenia and Adolescents with Cannabis Use Disorders

    ERIC Educational Resources Information Center

    Kumra, Sanjiv; Robinson, Paul; Tambyraja, Rabindra; Jensen, Daniel; Schimunek, Caroline; Houri, Alaa; Reis, Tiffany; Lim, Kelvin

    2012-01-01

    Objective: In early-onset schizophrenia (EOS), the earliest structural brain volumetric abnormalities appear in the parietal cortices. Early exposure to cannabis may represent an environmental risk factor for developing schizophrenia. This study characterized cerebral cortical gray matter structure in adolescents in regions of interest (ROIs) that…

  9. The Neural Dynamics of Fronto-Parietal Networks in Childhood Revealed using Magnetoencephalography.

    PubMed

    Astle, Duncan E; Luckhoo, Henry; Woolrich, Mark; Kuo, Bo-Cheng; Nobre, Anna C; Scerif, Gaia

    2015-10-01

    Our ability to hold information in mind is limited, requires a high degree of cognitive control, and is necessary for many subsequent cognitive processes. Children, in particular, are highly variable in how, trial-by-trial, they manage to recruit cognitive control in service of memory. Fronto-parietal networks, typically recruited under conditions where this cognitive control is needed, undergo protracted development. We explored, for the first time, whether dynamic changes in fronto-parietal activity could account for children's variability in tests of visual short-term memory (VSTM). We recorded oscillatory brain activity using magnetoencephalography (MEG) as 9- to 12-year-old children and adults performed a VSTM task. We combined temporal independent component analysis (ICA) with general linear modeling to test whether the strength of fronto-parietal activity correlated with VSTM performance on a trial-by-trial basis. In children, but not adults, slow frequency theta (4-7 Hz) activity within a right lateralized fronto-parietal network in anticipation of the memoranda predicted the accuracy with which those memory items were subsequently retrieved. These findings suggest that inconsistent use of anticipatory control mechanism contributes significantly to trial-to-trial variability in VSTM maintenance performance.

  10. The Role of the Parietal Lobe in Visual Extinction Studied with Transcranial Magnetic Stimulation

    ERIC Educational Resources Information Center

    Battelli, Lorella; Alvarez, George A.; Carlson, Thomas; Pascual-Leone, Alvaro

    2009-01-01

    Interhemispheric competition between homologous areas in the human brain is believed to be involved in a wide variety of human behaviors from motor activity to visual perception and particularly attention. For example, patients with lesions in the posterior parietal cortex are unable to selectively track objects in the contralesional side of…

  11. Role of Right Posterior Parietal Cortex in Maintaining Attention to Spatial Locations over Time

    ERIC Educational Resources Information Center

    Malhotra, Paresh; Coulthard, Elizabeth J.; Husain, Masud

    2009-01-01

    Recent models of human posterior parietal cortex (PPC) have variously emphasized its role in spatial perception, visuomotor control or directing attention. However, neuroimaging and lesion studies also suggest that the right PPC might play a special role in maintaining an alert state. Previously, assessments of right-hemisphere patients with…

  12. The Role of the Right Posterior Parietal Cortex in Temporal Order Judgment

    ERIC Educational Resources Information Center

    Woo, Sung-Ho; Kim, Ki-Hyun; Lee, Kyoung-Min

    2009-01-01

    Perceived order of two consecutive stimuli may not correspond to the order of their physical onsets. Such a disagreement presumably results from a difference in the speed of stimulus processing toward central decision mechanisms. Since previous evidence suggests that the right posterior parietal cortex (PPC) plays a role in modulating the…

  13. High Frequency rTMS over the Left Parietal Lobule Increases Non-Word Reading Accuracy

    ERIC Educational Resources Information Center

    Costanzo, Floriana; Menghini, Deny; Caltagirone, Carlo; Oliveri, Massimiliano; Vicari, Stefano

    2012-01-01

    Increasing evidence in the literature supports the usefulness of Transcranial Magnetic Stimulation (TMS) in studying reading processes. Two brain regions are primarily involved in phonological decoding: the left superior temporal gyrus (STG), which is associated with the auditory representation of spoken words, and the left inferior parietal lobe…

  14. The Neuroanatomical Basis for Posterior Superior Parietal Lobule Control Lateralization of Visuospatial Attention.

    PubMed

    Wu, Yan; Wang, Jiaojian; Zhang, Yun; Zheng, Dingchen; Zhang, Jinfeng; Rong, Menglin; Wu, Huawang; Wang, Yinyan; Zhou, Ke; Jiang, Tianzi

    2016-01-01

    The right hemispheric dominance in visuospatial attention in human brain has been well established. Converging evidence has documented that ventral posterior parietal cortex (PPC) plays an important role in visuospatial attention. The role of dorsal PPC subregions, especially the superior parietal lobule (SPL) in visuospatial attention is still controversial. In the current study, we used repetitive transcranial magnetic stimulation (rTMS) and diffusion magnetic resonance imaging (MRI) techniques to test the role of posterior SPL in visuospatial attention and to investigate the potential neuroanatomical basis for right hemisphere dominance in visuospatial function. Transcranial magnetic stimulation (TMS) results unraveled that the right SPL predominantly mediated visuospatial attention compared to left SPL. Anatomical connections analyses between the posterior SPL and the intrahemispheric frontal subregions and the contralateral PPC revealed that right posterior SPL has stronger anatomical connections with the ipsilateral middle frontal gyrus (MFG), with the ipsilateral inferior frontal gyrus (IFG), and with contralateral PPC than that of the left posterior SPL. Furthermore, these asymmetric anatomical connections were closely related to behavioral performances. Our findings indicate that SPL plays a crucial role in regulating visuospatial attention, and dominance of visuospatial attention results from unbalanced interactions between the bilateral fronto-parietal networks and the interhemispheric parietal network. PMID:27047351

  15. Coordinate expression of parietal endodermal functions in hybrids of embryonal carcinoma and endodermal cells.

    PubMed Central

    Howe, W E; Oshima, R G

    1982-01-01

    A derivative, FOT5, of the F9 murine embryonal carcinoma cell line which is resistant to ouabain and thioguanine was fused with a near diploid parietal endodermal cell line, PFHR9, Hybrid clones (ENEC1 to ENEC5) were isolated in HAT Medium containing ouabain at a frequency of approximately 2 x 10(-4). The DNA contents and chromosome number of the ENEC hybrids were approximately the sum of those of the parents. Five hybrid cell lines examined in detail expressed the following parietal endodermal functions: plasminogen activator activity, basement membrane proteins, and endodermal cytoskeletal proteins. Embryonal carcinoma characteristic functions (tumorigenicity, a stage specific embryonic antigen, and high alkaline phosphatase activity) were extinguished in the hybrids. No hybrid clones with embryonal carcinoma morphology were observed among 1,358 hybrid clones examined. Hybrids, propagated for over 100 generations, continued to express endodermal functions and not embryonal carcinoma functions. The coordinate expression of endodermal functions and the extinction of embryonal carcinoma functions in the ENEC hybrids suggest that the parietal endodermal cells contain diffusible activities which extinguish embryonal carcinoma functions and possibly cause the embryonal carcinoma genome to express parietal endodermal characteristics. Images PMID:7202115

  16. Task-Dependent Changes in Frontal-Parietal Activation and Connectivity During Visual Search.

    PubMed

    Maximo, Jose O; Neupane, Ajaya; Saxena, Nitesh; Joseph, Robert M; Kana, Rajesh K

    2016-05-01

    Visual search is an important skill in navigating and locating objects (a target) among distractors in our environment. Efficient and faster target detection involves reciprocal interaction between a viewer's attentional resources as well as salient target characteristics. The neural correlates of visual search have been extensively investigated over the last decades, suggesting the involvement of a frontal-parietal network comprising the frontal eye fields (FEFs) and intraparietal sulcus (IPS). In addition, activity and connectivity of these network changes as the visual search become complex and more demanding. The current functional magnetic resonance imaging study examined the modulation of the frontal-parietal network in response to cognitive demand in 22 healthy adult participants. In addition to brain activity, changes in functional connectivity and effective connectivity in this network were examined in response to easy and difficult visual search. Results revealed significantly increased activation in FEF, IPS, and supplementary motor area, more so in difficult search than in easy search. Functional and effective connectivity analyses showed enhanced connectivity in the frontal-parietal network during difficult search and enhanced information transfer from left to right hemisphere during the difficult search process. Our overall findings suggest that cognitive demand significantly increases brain resources across all three measures of brain processing. In sum, we found that goal-directed visual search engages a network of frontal-parietal areas that are modulated in relation to cognitive demand.

  17. Contrasting Effects of Vocabulary Knowledge on Temporal and Parietal Brain Structure across Lifespan

    ERIC Educational Resources Information Center

    Richardson, Fiona M.; Thomas, Michael S. C.; Filippi, Roberto; Harth, Helen; Price, Cathy J.

    2010-01-01

    Using behavioral, structural, and functional imaging techniques, we demonstrate contrasting effects of vocabulary knowledge on temporal and parietal brain structure in 47 healthy volunteers who ranged in age from 7 to 73 years. In the left posterior supramarginal gyrus, vocabulary knowledge was positively correlated with gray matter density in…

  18. Assembly and use of new task rules in fronto-parietal cortex.

    PubMed

    Dumontheil, Iroise; Thompson, Russell; Duncan, John

    2011-01-01

    Severe capacity limits, closely associated with fluid intelligence, arise in learning and use of new task rules. We used fMRI to investigate these limits in a series of multirule tasks involving different stimuli, rules, and response keys. Data were analyzed both during presentation of instructions and during later task execution. Between tasks, we manipulated the number of rules specified in task instructions, and within tasks, we manipulated the number of rules operative in each trial block. Replicating previous results, rule failures were strongly predicted by fluid intelligence and increased with the number of operative rules. In fMRI data, analyses of the instruction period showed that the bilateral inferior frontal sulcus, intraparietal sulcus, and presupplementary motor area were phasically active with presentation of each new rule. In a broader range of frontal and parietal regions, baseline activity gradually increased as successive rules were instructed. During task performance, we observed contrasting fronto-parietal patterns of sustained (block-related) and transient (trial-related) activity. Block, but not trial, activity showed effects of task complexity. We suggest that, as a new task is learned, a fronto-parietal representation of relevant rules and facts is assembled for future control of behavior. Capacity limits in learning and executing new rules, and their association with fluid intelligence, may be mediated by this load-sensitive fronto-parietal network. PMID:20146600

  19. Lower neuronal variability in the monkey dorsolateral prefrontal than posterior parietal cortex.

    PubMed

    Qi, Xue-Lian; Constantinidis, Christos

    2015-10-01

    The dorsolateral prefrontal and posterior parietal cortex are two brain areas involved in cognitive functions such as spatial attention and working memory. When tested with identical tasks, only subtle differences in firing rate are present between neurons recorded in the two areas. In this article we report that major differences in neuronal variability characterize the two areas during working memory. The Fano factors of spike counts in dorsolateral prefrontal neurons were consistently lower than those of the posterior parietal cortex across a range of tasks, epochs, and conditions in the same monkeys. Variability differences were observed despite minor differences in firing rates between the two areas in the tasks tested and higher overall firing rate in the prefrontal than in the posterior parietal sample. Other measures of neuronal discharge variability, such as the coefficient of variation of the interspike interval, displayed the same pattern of lower prefrontal variability. Fano factor values were negatively correlated with performance in the working memory task, suggesting that higher neuronal variability was associated with diminished task performance. The results indicate that information involving remembered stimuli is more reliably represented in the prefrontal than the posterior parietal cortex based on the variability of neuronal responses, and suggest functional differentiation between the two areas beyond differences in firing rate. PMID:26269556

  20. The precision of value-based choices depends causally on fronto-parietal phase coupling.

    PubMed

    Polanía, Rafael; Moisa, Marius; Opitz, Alexander; Grueschow, Marcus; Ruff, Christian C

    2015-01-01

    Which meal would you like today, chicken or pasta? For such value-based choices, organisms must flexibly integrate various types of sensory information about internal states and the environment to transform them into actions. Recent accounts suggest that these choice-relevant processes are mediated by information transfer between functionally specialized but spatially distributed brain regions in parietal and prefrontal cortex; however, it remains unclear whether such fronto-parietal communication is causally involved in guiding value-based choices. We find that transcranially inducing oscillatory desynchronization between the frontopolar and -parietal cortex leads to more inaccurate choices between food rewards while leaving closely matched perceptual decisions unaffected. Computational modelling shows that this exogenous manipulation leads to imprecise value assignments to the choice alternatives. Thus, our study demonstrates that accurate value-based decisions critically involve coherent rhythmic information transfer between fronto-parietal brain areas and establishes an experimental approach to non-invasively manipulate the precision of value-based choices in humans. PMID:26290482

  1. The Neuroanatomical Basis for Posterior Superior Parietal Lobule Control Lateralization of Visuospatial Attention

    PubMed Central

    Wu, Yan; Wang, Jiaojian; Zhang, Yun; Zheng, Dingchen; Zhang, Jinfeng; Rong, Menglin; Wu, Huawang; Wang, Yinyan; Zhou, Ke; Jiang, Tianzi

    2016-01-01

    The right hemispheric dominance in visuospatial attention in human brain has been well established. Converging evidence has documented that ventral posterior parietal cortex (PPC) plays an important role in visuospatial attention. The role of dorsal PPC subregions, especially the superior parietal lobule (SPL) in visuospatial attention is still controversial. In the current study, we used repetitive transcranial magnetic stimulation (rTMS) and diffusion magnetic resonance imaging (MRI) techniques to test the role of posterior SPL in visuospatial attention and to investigate the potential neuroanatomical basis for right hemisphere dominance in visuospatial function. Transcranial magnetic stimulation (TMS) results unraveled that the right SPL predominantly mediated visuospatial attention compared to left SPL. Anatomical connections analyses between the posterior SPL and the intrahemispheric frontal subregions and the contralateral PPC revealed that right posterior SPL has stronger anatomical connections with the ipsilateral middle frontal gyrus (MFG), with the ipsilateral inferior frontal gyrus (IFG), and with contralateral PPC than that of the left posterior SPL. Furthermore, these asymmetric anatomical connections were closely related to behavioral performances. Our findings indicate that SPL plays a crucial role in regulating visuospatial attention, and dominance of visuospatial attention results from unbalanced interactions between the bilateral fronto-parietal networks and the interhemispheric parietal network. PMID:27047351

  2. Human Topological Task Adapted for Rats: Spatial Information Processes of the Parietal Cortex

    PubMed Central

    Goodrich-Hunsaker, Naomi J.; Howard, Brian P.; Hunsaker, Michael R.; Kesner, Raymond P.

    2008-01-01

    Human research has shown that lesions of the parietal cortex disrupt spatial information processing, specifically topological information. Similar findings have been found in nonhumans. It has been difficult to determine homologies between human and non-human mnemonic mechanisms for spatial information processing because methodologies and neuropathology differ. The first objective of the present study was to adapt a previously established human task for rats. The second objective was to better characterize the role of parietal cortex (PC) and dorsal hippocampus (dHPC) for topological spatial information processing. Rats had to distinguish whether a ball inside a ring or a ball outside a ring was the correct, rewarded object. After rats reached criterion on the task (>95%) they were randomly assigned to a lesion group (control, PC, dHPC). Animals were then re-tested. Post-surgery data show that controls were 94% correct on average, dHPC rats were 89% correct on average, and PC rats were 56% correct on average. The results from the present study suggest that the parietal cortex, but not the dHPC processes topological spatial information. The present data are the first to support comparable topological spatial information processes of the parietal cortex in humans and rats. PMID:18571941

  3. Attentional Demands Predict Short-Term Memory Load Response in Posterior Parietal Cortex

    ERIC Educational Resources Information Center

    Magen, Hagit; Emmanouil, Tatiana-Aloi; McMains, Stephanie A.; Kastner, Sabine; Treisman, Anne

    2009-01-01

    Limits to the capacity of visual short-term memory (VSTM) indicate a maximum storage of only 3 or 4 items. Recently, it has been suggested that activity in a specific part of the brain, the posterior parietal cortex (PPC), is correlated with behavioral estimates of VSTM capacity and might reflect a capacity-limited store. In three experiments that…

  4. Lateralization of Egocentric and Allocentric Spatial Processing after Parietal Brain Lesions

    ERIC Educational Resources Information Center

    Iachini, Tina; Ruggiero, Gennaro; Conson, Massimiliano; Trojano, Luigi

    2009-01-01

    The purpose of this paper was to verify whether left and right parietal brain lesions may selectively impair egocentric and allocentric processing of spatial information in near/far spaces. Two Right-Brain-Damaged (RBD), 2 Left-Brain-Damaged (LBD) patients (not affected by neglect or language disturbances) and eight normal controls were submitted…

  5. Planning Movements in Visual and Physical Space in Monkey Posterior Parietal Cortex.

    PubMed

    Kuang, Shenbing; Morel, Pierre; Gail, Alexander

    2016-02-01

    Neurons in the posterior parietal cortex respond selectively for spatial parameters of planned goal-directed movements. Yet, it is still unclear which aspects of the movement the neurons encode: the spatial parameters of the upcoming physical movement (physical goal), or the upcoming visual limb movement (visual goal). To test this, we recorded neuronal activity from the parietal reach region while monkeys planned reaches under either normal or prism-reversed viewing conditions. We found predominant encoding of physical goals while fewer neurons were selective for visual goals during planning. In contrast, local field potentials recorded in the same brain region exhibited predominant visual goal encoding, similar to previous imaging data from humans. The visual goal encoding in individual neurons was neither related to immediate visual input nor to visual memory, but to the future visual movement. Our finding suggests that action planning in parietal cortex is not exclusively a precursor of impending physical movements, as reflected by the predominant physical goal encoding, but also contains spatial kinematic parameters of upcoming visual movement, as reflected by co-existing visual goal encoding in neuronal spiking. The co-existence of visual and physical goals adds a complementary perspective to the current understanding of parietal spatial computations in primates.

  6. Sex Differences in Parietal Lobe Morphology: Relationship to Mental Rotation Performance

    ERIC Educational Resources Information Center

    Koscik, Tim; O'Leary, Dan; Moser, David J.; Andreasen, Nancy C.; Nopoulos, Peg

    2009-01-01

    Structural magnetic resonance imaging (MRI) studies of the human brain have reported evidence for sexual dimorphism. In addition to sex differences in overall cerebral volume, differences in the proportion of gray matter (GM) to white matter (WM) volume have been observed, particularly in the parietal lobe. To our knowledge there have been no…

  7. Monitoring cerebral tissue oxygen saturation at frontal and parietal regions during carotid artery stenting.

    PubMed

    Meng, Lingzhong; Hall, Melanie; Settecase, Fabio; Higashida, Randall T; Gelb, Adrian W

    2016-04-01

    Cerebral oximetry is normally placed on the upper forehead to monitor the frontal lobe cerebral tissue oxygen saturation (SctO2). We present a case in which the SctO2 was simultaneously monitored at both frontal and parietal regions during internal carotid artery (ICA) stenting. Our case involves a 79-year-old man who presented after a sudden fall and was later diagnosed with a watershed ischemic stroke in the distal fields perfused by the left middle cerebral artery. He had diffuse atherosclerotic occlusive lesions in the carotid and cerebral arterial systems including an 85 % stenotic lesion in the left distal cervical ICA. The brain territory perfused by the left ICA was devoid of collateral flow from anterior and posterior communicating arteries due to an abnormal circle of Willis. During stenting, the SctO2 monitored at both frontal and parietal regions tracked the procedure-induced acute flow change. However, the baseline SctO2 values of frontal and parietal regions differed. The SctO2-MAP correlation was more consistent on the stroked hemisphere than the non-stroked hemisphere. This case showed that SctO2 can be reliably monitored at the parietal region, which is primarily perfused by the ICA. SctO2 of the stroked brain is more pressure dependent than the non-stroked brain.

  8. The Neural Dynamics of Fronto-Parietal Networks in Childhood Revealed using Magnetoencephalography.

    PubMed

    Astle, Duncan E; Luckhoo, Henry; Woolrich, Mark; Kuo, Bo-Cheng; Nobre, Anna C; Scerif, Gaia

    2015-10-01

    Our ability to hold information in mind is limited, requires a high degree of cognitive control, and is necessary for many subsequent cognitive processes. Children, in particular, are highly variable in how, trial-by-trial, they manage to recruit cognitive control in service of memory. Fronto-parietal networks, typically recruited under conditions where this cognitive control is needed, undergo protracted development. We explored, for the first time, whether dynamic changes in fronto-parietal activity could account for children's variability in tests of visual short-term memory (VSTM). We recorded oscillatory brain activity using magnetoencephalography (MEG) as 9- to 12-year-old children and adults performed a VSTM task. We combined temporal independent component analysis (ICA) with general linear modeling to test whether the strength of fronto-parietal activity correlated with VSTM performance on a trial-by-trial basis. In children, but not adults, slow frequency theta (4-7 Hz) activity within a right lateralized fronto-parietal network in anticipation of the memoranda predicted the accuracy with which those memory items were subsequently retrieved. These findings suggest that inconsistent use of anticipatory control mechanism contributes significantly to trial-to-trial variability in VSTM maintenance performance. PMID:25410426

  9. The role of parietal cortex in the formation of color and motion based concepts

    PubMed Central

    Cheadle, Samuel W.; Zeki, Semir

    2014-01-01

    Imaging evidence shows that separate subdivisions of parietal cortex, in and around the intraparietal sulcus (IPS), are engaged when stimuli are grouped according to color and to motion (Zeki and Stutters, 2013). Since grouping is an essential step in the formation of concepts, we wanted to learn whether parietal cortex is also engaged in the formation of concepts according to these two attributes. Using functional magnetic resonance imaging (fMRI), and choosing the recognition of concept-based color or motion stimuli as our paradigm, we found that there was strong concept-related activity in and around the IPS, a region whose homolog in the macaque monkey is known to receive direct but segregated anatomical inputs from V4 and V5. Parietal activity related to color concepts was juxtaposed but did not overlap with activity related to motion concepts, thus emphasizing the continuation of the segregation of color and motion into the conceptual system. Concurrent retinotopic mapping experiments showed that within the parietal cortex, concept-related activity increases within later stage IPS areas. PMID:25120447

  10. Temporo-Parietal Junction Activity in Theory-of-Mind Tasks: Falseness, Beliefs, or Attention

    ERIC Educational Resources Information Center

    Aichhorn, Markus; Perner, Josef; Weiss, Benjamin; Kronbichler, Martin; Staffen, Wolfgang; Ladurner, Gunther

    2009-01-01

    By combining the false belief (FB) and photo (PH) vignettes to identify theory-of-mind areas with the false sign (FS) vignettes, we re-establish the functional asymmetry between the left and right temporo-parietal junction (TPJ). The right TPJ (TPJ-R) is specially sensitive to processing belief information, whereas the left TPJ (TPJ-L) is equally…

  11. Space Radar Image of Giza Egypt - with enlargement

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This radar image shows the area west of the Nile River near Cairo, Egypt. The Nile River is the dark band along the right side of the image and it flows approximately due North from the bottom to the right. The boundary between dense urbanization and the desert can be clearly seen between the bright and dark areas in the center of the image. This boundary represents the approximate extent of yearly Nile flooding which played an important part in determining where people lived in ancient Egypt. This land usage pattern persists to this day. The pyramids at Giza appear as three bright triangles aligned with the image top just at the boundary of the urbanized area. They are also shown enlarged in the inset box in the top left of the image. The Great Pyramid of Khufu (Cheops in Greek) is the northern most of the three Giza pyramids. The side-looking radar illuminates the scene from the top, the two sides of the pyramids facing the radar reflect most of the energy back to the antenna and appear radar bright; the two sides away from the radar reflect less energy back and appear dark Two additional pyramids can be seen left of center in the lower portion of the image. The modern development in the desert on the left side of the image is the Sixth of October City, an area of factories and residences started by Anwar Sadat to relieve urban crowding. The image was taken on April 19, 1994 by the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) aboard the shuttle Endeavour. SIR-C/X-SAR, a joint mission of the German, Italian and the United States space agencies, is part of NASA's Mission to Planet Earth. The image is centered on latitude 29.72 degrees North latitude and 30.83 degrees East longitude. The area shown is approximately 20 kilometers by 30 kilometers. The colors in the image are assigned to different frequencies and polarizations of the radar as follows: red is L-band horizontally transmitted, horizontally received; green is C

  12. Molecular insights into evolution of the vertebrate gut: focus on stomach and parietal cells in the marsupial, Macropus eugenii.

    PubMed

    Kwek, Joly; De Iongh, Robbert; Nicholas, Kevin; Familari, Mary

    2009-09-15

    Gastrulation in vertebrate embryos results in the formation of the primary germ layers: ectoderm, mesoderm and endoderm, which contain the progenitors of the tissues of the entire fetal body. Extensive studies undertaken in Xenopus, zebrafish and mouse have revealed a high degree of conservation in the genes and cellular mechanisms regulating endoderm formation. Nodal, Mix and Sox gene factor families have been implicated in the specification of the endoderm across taxa. Considerably less is known about endoderm development in marsupials. In this study we review what is known about the molecular aspects of endoderm development, focusing on evolution and development of the stomach and parietal cells and highlight recent studies on parietal cells in the stomach of Tammar Wallaby, Macropus eugenii. Although the regulation of parietal cells has been extensively studied, very little is known about the regulation of parietal cell differentiation. Intriguingly, during late-stage forestomach maturation in M. eugenii, there is a sudden and rapid loss of parietal cells, compared with the sharp increase in parietal cell numbers in the hindstomach region. This has provided a unique opportunity to study the development and regulation of parietal cell differentiation. A PCR-based subtractive hybridization strategy was used to identify candidate genes involved in this phenomenon. This will allow us to dissect the molecular mechanisms that underpin regulation of parietal cell development and differentiation, which have been a difficult process to study and provide markers that can be used to study the evolutionary origin of these cells in vertebrates.

  13. Fronto-Parietal Connectivity Is a Non-Static Phenomenon with Characteristic Changes during Unconsciousness

    PubMed Central

    Kochs, Eberhard F.; Ilg, Rüdiger; Schneider, Gerhard

    2014-01-01

    Background It has been previously shown that loss of consciousness is associated with a breakdown of dominating fronto-parietal feedback connectivity as assessed by electroencephalogram (EEG) recordings. Structure and strength of network connectivity may change over time. Aim of the current study is to investigate cortico-cortical connectivity at different time intervals during consciousness and unconsciousness. For this purpose, EEG symbolic transfer entropy (STEn) was calculated to indicate cortico-cortical information transfer at different transfer times. Methods The study was performed in 15 male volunteers. 29-channel EEG was recorded during consciousness and propofol-induced unconsciousness. EEG data were analyzed by STEn, which quantifies intensity and directionality of the mutual information flow between two EEG channels. STEn was computed over fronto-parietal channel pair combinations (10 s length, 0.5–45 Hz total bandwidth) to analyze changes of intercortical directional connectivity. Feedback (fronto → parietal) and feedforward (parieto → frontal) connectivity was calculated for transfer times from 25 ms to 250 ms in 5 ms steps. Transfer times leading to maximum directed interaction were identified to detect changes of cortical information transfer (directional connectivity) induced by unconsciousness (p<0.05). Results The current analyses show that fronto-parietal connectivity is a non-static phenomenon. Maximum detected interaction occurs at decreased transfer times during propofol-induced unconsciousness (feedback interaction: 60 ms to 40 ms, p = 0.002; feedforward interaction: 65 ms to 45 ms, p = 0.001). Strength of maximum feedback interaction decreases during unconsciousness (p = 0.026), while no effect of propofol was observed on feedforward interaction. During both consciousness and unconsciousness, intensity of fronto-parietal interaction fluctuates with increasing transfer times. Conclusion Non-stationarity of directional

  14. Contribution of the posterior parietal cortex in reaching, grasping, and using objects and tools.

    PubMed

    Vingerhoets, Guy

    2014-01-01

    Neuropsychological and neuroimaging data suggest a differential contribution of posterior parietal regions during the different components of a transitive gesture. Reaching requires the integration of object location and body position coordinates and reaching tasks elicit bilateral activation in different foci along the intraparietal sulcus. Grasping requires a visuomotor match between the object's shape and the hand's posture. Lesion studies and neuroimaging confirm the importance of the anterior part of the intraparietal sulcus for human grasping. Reaching and grasping reveal bilateral activation that is generally more prominent on the side contralateral to the hand used or the hemifield stimulated. Purposeful behavior with objects and tools can be assessed in a variety of ways, including actual use, pantomimed use, and pure imagery of manipulation. All tasks have been shown to elicit robust activation over the left parietal cortex in neuroimaging, but lesion studies have not always confirmed these findings. Compared to pantomimed or imagined gestures, actual object and tool use typically produces activation over the left primary somatosensory region. Neuroimaging studies on pantomiming or imagery of tool use in healthy volunteers revealed neural responses in possibly separate foci in the left supramarginal gyrus. In sum, the parietal contribution of reaching and grasping of objects seems to depend on a bilateral network of intraparietal foci that appear organized along gradients of sensory and effector preferences. Dorsal and medial parietal cortex appears to contribute to the online monitoring/adjusting of the ongoing prehensile action, whereas the functional use of objects and tools seems to involve the inferior lateral parietal cortex. This functional input reveals a clear left lateralized activation pattern that may be tuned to the integration of acquired knowledge in the planning and guidance of the transitive movement.

  15. Matrix metalloproteinase-9 expression is enhanced in renal parietal epithelial cells of zucker diabetic Fatty rats and is induced by albumin in in vitro primary parietal cell culture.

    PubMed

    Zhang, Yuanyuan; George, Jasmine; Li, Yun; Olufade, Rebecca; Zhao, Xueying

    2015-01-01

    As a subfamily of matrix metalloproteinases (MMPs), gelatinases including MMP-2 and MMP-9 play an important role in remodeling and homeostasis of the extracellular matrix. However, conflicting results have been reported regarding their expression level and activity in the diabetic kidney. This study investigated whether and how MMP-9 expression and activity were changed in glomerular epithelial cells upon albumin overload. In situ zymography, immunostaining and Western blot for renal MMP gelatinolytic activity and MMP-9 protein expression were performed in Zucker lean and Zucker diabetic rats. Confocal microscopy revealed a focal increase in gelatinase activity and MMP-9 protein in the glomeruli of diabetic rats. Increased glomerular MMP-9 staining was mainly observed in hyperplastic parietal epithelial cells (PECs) expressing claudin-1 in the diabetic kidneys. Interestingly, increased parietal MMP-9 was often accompanied by decreased staining for podocyte markers (nephrin and podocalyxin) in the sclerotic area of affected glomeruli in diabetic rats. Additionally, urinary excretion of podocyte marker proteins was significantly increased in association with the levels of MMP-9 and albumin in the urine of diabetic animals. To evaluate the direct effect of albumin on expression and activity of MMP-9, primary cultured rat glomerular PECs were incubated with rat serum albumin (0.25 - 1 mg/ml) for 24 - 48 hrs. MMP-9 mRNA levels were significantly increased following albumin treatment. Meanwhile, albumin administration resulted in a dose-dependent increase in MMP-9 protein and activity in culture supernatants of PECs. Moreover, albumin activated p44/42 mitogen-activated protein kinase (MAPK) in PECs. Inhibition of p44/42 MAPK suppressed albumin-induced MMP-9 secretion from glomerular PECs. Taken together, we have demonstrated that an up-regulation of MMP-9 in activated parietal epithelium is associated with a loss of adjacent podocytes in progressive diabetic nephropathy

  16. Cooperative diplomacy: Citizens, sovereignty, and the logic of democratic enlargement

    NASA Astrophysics Data System (ADS)

    Ndungu, Anthony Mark

    2000-12-01

    that intergovernmental agreement on compliance questions is most likely to occur when decision-making and policy-implementing processes are decentralized, and when governments establish and support decentralized intra- and trans-governmental institutions that enable private domestic groups of individuals to participate in international governance through two mechanisms. First, those decentralized institutions facilitate the formation of transnational coalitions of politically autonomous private domestic groups that can serve as a ``horizontal transmission belt'' for ideas and practices among private and public proponents of the major opposing domestic positions, thereby generating public transnational deliberation on compliance, monitoring and distributive questions. Second, politically autonomous private domestic groups can, by engaging in performance-based partnerships with senior government officials, also serve as a ``vertical transmission belt'' between domestic and intergovernmental regimes and vice versa, thereby encouraging their respective governments to adapt the social practices in issue-specific domestic regimes to international structural forces. These findings have significant ramifications for the concept of democratic enlargement, the institutionalization of competitive pluralism in non- liberal states. The robustness, across changes in administrations both at home and abroad, of the norms codified in international agreements may hinge on institutionalizing the participation of politically autonomous private domestic groups in decentralized intra- and trans-governmental decision-making and policy- implementing processes.

  17. ES1 is a mitochondrial enlarging factor contributing to form mega-mitochondria in zebrafish cones.

    PubMed

    Masuda, Takamasa; Wada, Yasutaka; Kawamura, Satoru

    2016-03-01

    Total mass of mitochondria increases during cell proliferation and differentiation through mitochondrial biogenesis, which includes mitochondrial proliferation and growth. During the mitochondrial growth, individual mitochondria have been considered to be enlarged independently of mitochondrial fusion. However, molecular basis for this enlarging process has been poorly understood. Cone photoreceptor cells in the retina possess large mitochondria, so-called mega-mitochondria that have been considered to arise via the enlarging process. Here we show that ES1 is a novel mitochondria-enlarging factor contributing to form mega-mitochondria in cones. ES1 is specifically expressed in cones and localized to mitochondria including mega-mitochondria. Knockdown of ES1 markedly reduced the mitochondrial size in cones. In contrast, ectopic expression of ES1 in rods significantly increased both the size of individual mitochondria and the total mass of the mitochondrial cluster without changing the number of them. RNA-seq analysis showed that ERRα and its downstream mitochondrial genes were significantly up-regulated in the ES1-expressing rods, suggesting facilitation of mitochondrial enlargement via ERRα-dependent processes. Furthermore, higher energy state was detected in the ES1-expressing rods, indicating that the enlarged mitochondria by ES1 are capable of producing high energy. ES1 is the mitochondrial protein that is first found to promote enlargement of individual mitochondria.

  18. ES1 is a mitochondrial enlarging factor contributing to form mega-mitochondria in zebrafish cones

    PubMed Central

    Masuda, Takamasa; Wada, Yasutaka; Kawamura, Satoru

    2016-01-01

    Total mass of mitochondria increases during cell proliferation and differentiation through mitochondrial biogenesis, which includes mitochondrial proliferation and growth. During the mitochondrial growth, individual mitochondria have been considered to be enlarged independently of mitochondrial fusion. However, molecular basis for this enlarging process has been poorly understood. Cone photoreceptor cells in the retina possess large mitochondria, so-called mega-mitochondria that have been considered to arise via the enlarging process. Here we show that ES1 is a novel mitochondria-enlarging factor contributing to form mega-mitochondria in cones. ES1 is specifically expressed in cones and localized to mitochondria including mega-mitochondria. Knockdown of ES1 markedly reduced the mitochondrial size in cones. In contrast, ectopic expression of ES1 in rods significantly increased both the size of individual mitochondria and the total mass of the mitochondrial cluster without changing the number of them. RNA-seq analysis showed that ERRα and its downstream mitochondrial genes were significantly up-regulated in the ES1-expressing rods, suggesting facilitation of mitochondrial enlargement via ERRα-dependent processes. Furthermore, higher energy state was detected in the ES1-expressing rods, indicating that the enlarged mitochondria by ES1 are capable of producing high energy. ES1 is the mitochondrial protein that is first found to promote enlargement of individual mitochondria. PMID:26926452

  19. Phospholipids trigger Cryptococcus neoformans capsular enlargement during interactions with amoebae and macrophages.

    PubMed

    Chrisman, Cara J; Albuquerque, Patricia; Guimaraes, Allan J; Nieves, Edward; Casadevall, Arturo

    2011-05-01

    A remarkable aspect of the interaction of Cryptococcus neoformans with mammalian hosts is a consistent increase in capsule volume. Given that many aspects of the interaction of C. neoformans with macrophages are also observed with amoebae, we hypothesized that the capsule enlargement phenomenon also had a protozoan parallel. Incubation of C. neoformans with Acanthamoeba castellanii resulted in C. neoformans capsular enlargement. The phenomenon required contact between fungal and protozoan cells but did not require amoeba viability. Analysis of amoebae extracts showed that the likely stimuli for capsule enlargement were protozoan polar lipids. Extracts from macrophages and mammalian serum also triggered cryptococcal capsular enlargement. C. neoformans capsule enlargement required expression of fungal phospholipase B, but not phospholipase C. Purified phospholipids, in particular, phosphatidylcholine, and derived molecules triggered capsular enlargement with the subsequent formation of giant cells. These results implicate phospholipids as a trigger for both C. neoformans capsule enlargement in vivo and exopolysaccharide production. The observation that the incubation of C. neoformans with phospholipids led to the formation of giant cells provides the means to generate these enigmatic cells in vitro. Protozoan- or mammalian-derived polar lipids could represent a danger signal for C. neoformans that triggers capsular enlargement as a non-specific defense mechanism against potential predatory cells. Hence, phospholipids are the first host-derived molecules identified to trigger capsular enlargement. The parallels apparent in the capsular response of C. neoformans to both amoebae and macrophages provide additional support for the notion that certain aspects of cryptococcal virulence emerged as a consequence of environmental interactions with other microorganisms such as protists.

  20. Temporo-parietal and fronto-parietal lobe contributions to theory of mind and executive control: an fMRI study of verbal jokes

    PubMed Central

    Chan, Yu-Chen; Lavallee, Joseph P.

    2015-01-01

    ‘Getting a joke’ always requires resolving an apparent incongruity, but the particular cognitive operations called upon vary depending on the nature of the joke itself. Previous research has identified the primary neural correlates of the cognitive and affective processes called upon to respond to humor generally, but little work has been done on the substrates underlying the distinct cognitive operations required to comprehend particular joke types. This study explored the neural correlates of the cognitive processes required to successfully comprehend three joke types: bridging-inference jokes (BJs), exaggeration jokes (EJs), and ambiguity jokes (AJs). For all joke types, the left dlPFC appeared to support common cognitive mechanisms, such as script-shifting, while the vACC was associated with affective appreciation. The temporo-parietal lobe (TPJ and MTG) was associated with BJs, suggesting involvement of these regions with ‘theory of mind’ processing. The fronto-parietal lobe (IPL and IFG) was associated with both EJs and AJs, suggesting that it supports executive control processes such as retrieval from episodic memory, self-awareness, and language-based decoding. The social-affective appreciation of verbal jokes was associated with activity in the orbitofrontal cortex, amygdala, and parahippocampal gyrus. These results allow a more precise account of the neural processes required to support the particular cognitive operations required for the understanding of different types of humor. PMID:26388803

  1. A Study of Temporal Aspect of Posterior Parietal Cortex in Visual Search Using Transcranial Magnetic Stimulation

    NASA Astrophysics Data System (ADS)

    Ge, Sheng; Matsuoka, Akira; Ueno, Shoogo; Iramina, Keiji

    It is known that the posterior parietal cortex (PPC) plays a dominant role in spatial processing during visual search. However, the temporal aspect of the PPC is unclear. In the present study, to investigate the temporal aspects of the PPC in feature search, we applied Transcranial Magnetic Stimulation (TMS) over the right PPC with the TMS stimulus onset asynchronies (SOAs) set at 100, 150, 200 and 250 ms after visual search stimulation. We found that when SOA was set at 150 ms, compared to the sham TMS condition, there was a significant elevation in response time when TMS pulses were applied. However, there was no significant difference between the TMS and sham TMS conditions for the other SOA settings. Therefore, we suggest that the spatial processing of feature search is probably processed in the posterior parietal cortex at about 150-170 ms after visual search stimuli presentation.

  2. Pseudodystonic hand posturing contralateral to a metastasis of the parietal association cortex.

    PubMed

    Coria, F; Blanco Martín, A I; Rivas Vilas, M D

    2000-10-01

    A 56 year-old patient, with a history of surgically removed breast cancer three years earlier, presented with incoordination of hand movements while playing piano. Neurological examination disclosed mild position sensory loss and limb-kinetic apraxia of the distal part of the right upper extremity. The most conspicuous neurological sign was a dystonic posturing of the right hand, which was only elicited when the patient outstretched her arms with the eyes closed. MRI revealed a metastatic lesion involving the left parietal cortex. The association of focal dystonic postures with lesions of the parietal association cortex indicates that dystonia may feature damage of brain cortical areas far from the basal ganglia. In addition, this provides support to the hypothesis that impairment of sensory pathways may play a role in the origin of some hyperkinetic movement disorders, such as dystonia and athetosis.

  3. Decoding the view expectation during learned maze navigation from human fronto-parietal network

    PubMed Central

    Shikauchi, Yumi; Ishii, Shin

    2015-01-01

    Humans use external cues and prior knowledge about the environment to monitor their positions during spatial navigation. View expectation is essential for correlating scene views with a cognitive map. To determine how the brain performs view expectation during spatial navigation, we applied a multiple parallel decoding technique to functional magnetic resonance imaging (fMRI) when human participants performed scene choice tasks in learned maze navigation environments. We decoded participants’ view expectation from fMRI signals in parietal and medial prefrontal cortices, whereas activity patterns in occipital cortex represented various types of external cues. The decoder’s output reflected participants’ expectations even when they were wrong, corresponding to subjective beliefs opposed to objective reality. Thus, view expectation is subjectively represented in human brain, and the fronto-parietal network is involved in integrating external cues and prior knowledge during spatial navigation. PMID:26631641

  4. Parietal dysfunction during number processing in children with fetal alcohol spectrum disorders

    PubMed Central

    Woods, K.J.; Meintjes, E.M.; Molteno, C.D.; Jacobson, S.W.; Jacobson, J.L.

    2015-01-01

    Number processing deficits are frequently seen in children prenatally exposed to alcohol. Although the parietal lobe, which is known to mediate several key aspects of number processing, has been shown to be structurally impaired in fetal alcohol spectrum disorders (FASD), effects on functional activity in this region during number processing have not previously been investigated. This fMRI study of 49 children examined differences in activation associated with prenatal alcohol exposure in five key parietal regions involved in number processing, using tasks involving simple addition and magnitude comparison. Despite generally similar behavioral performance, in both tasks greater prenatal alcohol exposure was related to less activation in an anterior section of the right horizontal intraparietal sulcus known to mediate mental representation and manipulation of quantity. Children with fetal alcohol syndrome and partial fetal alcohol syndrome appeared to compensate for this deficit by increased activation of the angular gyrus during the magnitude comparison task. PMID:26199871

  5. Making sense of another mind: the role of the right temporo-parietal junction.

    PubMed

    Saxe, Rebecca; Wexler, Anna

    2005-01-01

    Human adults conceive of one another as beings with minds, and attribute to one another mental states like perceptions, desires and beliefs. That is, we understand other people using a 'Theory of Mind'. The current study investigated the contributions of four brain regions to Theory of Mind reasoning. The right temporo-parietal junction (RTPJ) was recruited selectively for the attribution of mental states, and not for other socially relevant facts about a person, and the response of the RTPJ was modulated by the congruence or incongruence of multiple relevant facts about the target's mind. None of the other three brain regions commonly implicated in Theory of Mind reasoning--the left temporo-parietal junction (LTPJ), posterior cingulate (PC) and medial prefrontal cortex (MPFC)--showed an equally selective profile of response. The implications of these results for an alternative theory of reasoning about other minds--Simulation Theory--are discussed. PMID:15936784

  6. Parietal dysfunction during number processing in children with fetal alcohol spectrum disorders.

    PubMed

    Woods, K J; Meintjes, E M; Molteno, C D; Jacobson, S W; Jacobson, J L

    2015-01-01

    Number processing deficits are frequently seen in children prenatally exposed to alcohol. Although the parietal lobe, which is known to mediate several key aspects of number processing, has been shown to be structurally impaired in fetal alcohol spectrum disorders (FASD), effects on functional activity in this region during number processing have not previously been investigated. This fMRI study of 49 children examined differences in activation associated with prenatal alcohol exposure in five key parietal regions involved in number processing, using tasks involving simple addition and magnitude comparison. Despite generally similar behavioral performance, in both tasks greater prenatal alcohol exposure was related to less activation in an anterior section of the right horizontal intraparietal sulcus known to mediate mental representation and manipulation of quantity. Children with fetal alcohol syndrome and partial fetal alcohol syndrome appeared to compensate for this deficit by increased activation of the angular gyrus during the magnitude comparison task.

  7. Differential diagnosis of bilateral parietal abnormalities in I-123 IMP SPECT imaging

    SciTech Connect

    Kuwabara, Y.; Ichiya, Y.; Otsuka, M.; Tahara, T.; Fukumura, T.; Gunasekera, R.; Masuda, K. )

    1990-12-01

    This report discusses the clinical significance of bilateral parietal abnormalities on I-123 IMP SPECT imaging in 158 patients with cerebral disorders. This pattern was seen in 15 out of 21 patients with Alzheimer's disease; it was also seen in 4 out of 5 patients with Parkinson's disease with dementia, in 3 out of 17 patients with vascular dementia, in 1 out of 36 patients with cerebral infarction without dementia, in 1 out of 2 patients with hypoglycemia, and in 1 out of 2 patients with CO intoxication. Detection of bilateral parietal abnormalities is a useful finding in the diagnosis of Alzheimer's disease, but one should keep in mind that other cerebral disorders may also show a similar pattern with I-123 IMP SPECT imaging.

  8. Parietal dysfunction during number processing in children with fetal alcohol spectrum disorders.

    PubMed

    Woods, K J; Meintjes, E M; Molteno, C D; Jacobson, S W; Jacobson, J L

    2015-01-01

    Number processing deficits are frequently seen in children prenatally exposed to alcohol. Although the parietal lobe, which is known to mediate several key aspects of number processing, has been shown to be structurally impaired in fetal alcohol spectrum disorders (FASD), effects on functional activity in this region during number processing have not previously been investigated. This fMRI study of 49 children examined differences in activation associated with prenatal alcohol exposure in five key parietal regions involved in number processing, using tasks involving simple addition and magnitude comparison. Despite generally similar behavioral performance, in both tasks greater prenatal alcohol exposure was related to less activation in an anterior section of the right horizontal intraparietal sulcus known to mediate mental representation and manipulation of quantity. Children with fetal alcohol syndrome and partial fetal alcohol syndrome appeared to compensate for this deficit by increased activation of the angular gyrus during the magnitude comparison task. PMID:26199871

  9. Optic ataxia: from Balint’s syndrome to the parietal reach region

    PubMed Central

    Andersen, Richard A.; Andersen, Kristen N.; Hwang, EunJung; Hauschild, Markus

    2014-01-01

    Optic ataxia is a high order deficit in reaching to visual goals that occurs with posterior parietal cortex (PPC) lesions. It is a component of Balint’s syndrome that also includes attentional and gaze disorders. Aspects of optic ataxia are misreaching in the contralesional visual field, difficulty preshaping the hand for grasping, and an inability to correct reaches online. Recent research in non-human primates (NHPs) suggests that many aspects of Balint’s syndrome and optic ataxia are a result of damage to specific functional modules for reaching, saccades, grasp, attention, and state estimation. The deficits from large lesions in humans are likely composite effects from damage to combinations of these functional modules. Interactions between these modules, either within posterior parietal cortex or downstream within frontal cortex, may account for more complex behaviors such as hand-eye coordination and reach-to-grasp. PMID:24607223

  10. Negligible fronto-parietal BOLD activity accompanying unreportable switches in bistable perception

    PubMed Central

    Brascamp, Jan; Blake, Randolph; Knapen, Tomas

    2015-01-01

    The human brain's executive systems play a vital role in deciding and selecting among actions. Selection among alternatives also occurs in the perceptual domain, for instance when perception switches between interpretations during perceptual bistability. Whether executive systems also underlie this functionality remains debated, with known fronto-parietal concomitants of perceptual switches being variously interpreted as reflecting the switches' cause, or as reflecting their consequences. We developed a paradigm where the two eyes receive different inputs and perception demonstrably switches between these inputs, yet where switches themselves are so inconspicuous as to become unreportable, minimizing their executive consequences. Fronto-parietal fMRI BOLD responses that accompany perceptual switches were similarly minimized in this paradigm, indicating that these reflect the switches' consequences rather than their cause. We conclude that perceptual switches do not always rely on executive brain areas, and that processes responsible for selection among alternatives may operate outside of the brain's executive systems. PMID:26436901

  11. Sensory monitoring of prehension in the parietal lobe: a study using digital video.

    PubMed

    Gardner, Esther P; Debowy, Daniel J; Ro, Jin Y; Ghosh, Soumya; Babu, K Srinivasa

    2002-09-20

    Digital video provides technological tools for monitoring hand kinematics during prehension, and for correlating motor behavior with the simultaneously recorded firing patterns of neurons in parietal cortex of monkeys. The constancy of the hand action in the task allowed us to derive population responses of neurons in both S-I and posterior parietal cortex (PPC) from serial single unit recordings. Activity of PPC neurons preceded that in S-I, and was often shape-selective for particular objects, suggesting that they play an important role in motor planning of prehension. Detailed sensory monitoring of hand-object interactions occurred in S-I, where distinct groups of neurons responded to specific behaviors such as grasping, lifting, holding or releasing objects.

  12. Alice in Wonderland Syndrome associated with a temporo-parietal cavernoma.

    PubMed

    Philip, Michelle; Kornitzer, Jeffery; Marks, David; Lee, Huey-Jen; Souayah, Nizar

    2015-12-01

    Alice in Wonderland Syndrome (AIWS) is characterized by a rare constellation of perceptual disturbances including distorted body image, metamorphopsia, and visual hallucinations. In this report, we relate a unique case of AIWS in a woman with a right temporo-parietal cavernoma. AIWS in this patient may be secondary to epileptiform activity associated with the cavernoma and improved with anti-epileptic treatment. PMID:25663031

  13. Phospho-regulated ACAP4-Ezrin interaction is essential for histamine-stimulated parietal cell secretion.

    PubMed

    Ding, Xia; Deng, Hui; Wang, Dongmei; Zhou, Jiajia; Huang, Yuejia; Zhao, Xuannv; Yu, Xue; Wang, Ming; Wang, Fengsong; Ward, Tarsha; Aikhionbare, Felix; Yao, Xuebiao

    2010-06-11

    The ezrin-radixin-moesin proteins provide a regulated linkage between membrane proteins and the cortical cytoskeleton and also participate in signal transduction pathways. Ezrin is localized to the apical membrane of parietal cells and couples the protein kinase A activation cascade to the regulated HCl secretion. Our recent proteomic study revealed a protein complex of ezrin-ACAP4-ARF6 essential for volatile membrane remodeling (Fang, Z., Miao, Y., Ding, X., Deng, H., Liu, S., Wang, F., Zhou, R., Watson, C., Fu, C., Hu, Q., Lillard, J. W., Jr., Powell, M., Chen, Y., Forte, J. G., and Yao, X. (2006) Mol. Cell Proteomics 5, 1437-1449). However, knowledge of whether ACAP4 physically interacts with ezrin and how their interaction is integrated into membrane-cytoskeletal remodeling has remained elusive. Here we provide the first evidence that ezrin interacts with ACAP4 in a protein kinase A-mediated phosphorylation-dependent manner through the N-terminal 400 amino acids of ACAP4. ACAP4 locates in the cytoplasmic membrane in resting parietal cells but translocates to the apical plasma membrane upon histamine stimulation. ACAP4 was precipitated with ezrin from secreting but not resting parietal cell lysates, suggesting a phospho-regulated interaction. Indeed, this interaction is abolished by phosphatase treatment and validated by an in vitro reconstitution assay using phospho-mimicking ezrin(S66D). Importantly, ezrin specifies the apical distribution of ACAP4 in secreting parietal cells because either suppression of ezrin or overexpression of non-phosphorylatable ezrin prevents the apical localization of ACAP4. In addition, overexpressing GTPase-activating protein-deficient ACAP4 results in an inhibition of apical membrane-cytoskeletal remodeling and gastric acid secretion. Taken together, these results define a novel molecular mechanism linking ACAP4-ezrin interaction to polarized epithelial secretion.

  14. Praxis-induced reflex seizures mainly precipitated by writing due to a parietal focal cortical dysplasia.

    PubMed

    Racicot, Frédéric; Obaid, Sami; Bouthillier, Alain; Guillon-Létourneau, Laurent; Clément, Jean-François; Nguyen, Dang Khoa

    2016-01-01

    We report the case of a 23-year-old left-handed woman with medically intractable praxis-induced reflex seizures mainly precipitated by writing. Selective resection of subtle end-of-sulcus cortical dysplasia in the right inferior parietal lobule resulted in freedom from seizures. To the best of our knowledge, this is the first case of praxis-induced reflex seizures mainly precipitated by writing in which a focal lesion was found and treated successfully by surgery. PMID:27630817

  15. Frontal and parietal cortical interactions with distributed visual representations during selective attention and action selection.

    PubMed

    Nelissen, Natalie; Stokes, Mark; Nobre, Anna C; Rushworth, Matthew F S

    2013-10-16

    Using multivoxel pattern analysis (MVPA), we studied how distributed visual representations in human occipitotemporal cortex are modulated by attention and link their modulation to concurrent activity in frontal and parietal cortex. We detected similar occipitotemporal patterns during a simple visuoperceptual task and an attention-to-working-memory task in which one or two stimuli were cued before being presented among other pictures. Pattern strength varied from highest to lowest when the stimulus was the exclusive focus of attention, a conjoint focus, and when it was potentially distracting. Although qualitatively similar effects were seen inside regions relatively specialized for the stimulus category and outside, the former were quantitatively stronger. By regressing occipitotemporal pattern strength against activity elsewhere in the brain, we identified frontal and parietal areas exerting top-down control over, or reading information out from, distributed patterns in occipitotemporal cortex. Their interactions with patterns inside regions relatively specialized for that stimulus category were higher than those with patterns outside those regions and varied in strength as a function of the attentional condition. One area, the frontal operculum, was distinguished by selectively interacting with occipitotemporal patterns only when they were the focus of attention. There was no evidence that any frontal or parietal area actively inhibited occipitotemporal representations even when they should be ignored and were suppressed. Using MVPA to decode information within these frontal and parietal areas showed that they contained information about attentional context and/or readout information from occipitotemporal cortex to guide behavior but that frontal regions lacked information about category identity.

  16. Decision and action planning signals in human posterior parietal cortex during delayed perceptual choices.

    PubMed

    Tosoni, Annalisa; Corbetta, Maurizio; Calluso, Cinzia; Committeri, Giorgia; Pezzulo, Giovanni; Romani, G L; Galati, Gaspare

    2014-04-01

    During simple perceptual decisions, sensorimotor neurons in monkey fronto-parietal cortex represent a decision variable that guides the transformation of sensory evidence into a motor response, supporting the view that mechanisms for decision-making are closely embedded within sensorimotor structures. Within these structures, however, decision signals can be dissociated from motor signals, thus indicating that sensorimotor neurons can play multiple and independent roles in decision-making and action selection/planning. Here we used functional magnetic resonance imaging to examine whether response-selective human brain areas encode signals for decision-making or action planning during a task requiring an arbitrary association between face pictures (male vs. female) and specific actions (saccadic eye vs. hand pointing movements). The stimuli were gradually unmasked to stretch the time necessary for decision, thus maximising the temporal separation between decision and action planning. Decision-related signals were measured in parietal and motor/premotor regions showing a preference for the planning/execution of saccadic or pointing movements. In a parietal reach region, decision-related signals were specific for the stimulus category associated with its preferred pointing response. By contrast, a saccade-selective posterior intraparietal sulcus region carried decision-related signals even when the task required a pointing response. Consistent signals were observed in the motor/premotor cortex. Whole-brain analyses indicated that, in our task, the most reliable decision signals were found in the same neural regions involved in response selection. However, decision- and action-related signals within these regions can be dissociated. Differences between the parietal reach region and posterior intraparietal sulcus plausibly depend on their functional specificity rather than on the task structure.

  17. Distinguishing Intentions from Desires: Contributions of the Frontal and Parietal Lobes

    ERIC Educational Resources Information Center

    Chiavarino, Claudia; Apperly, Ian A.; Humphreys, Glyn W.

    2010-01-01

    The ability to represent desires and intentions as two distinct mental states was investigated in patients with parietal (N = 8) and frontal (N = 6) lesions and in age-matched controls (N = 7). A task was used where the satisfaction of the desire and the fulfilment of the intention did not co-vary and were manipulated in a 2 x 2 set. In two…

  18. Representation of remembered stimuli and task information in the monkey dorsolateral prefrontal and posterior parietal cortex.

    PubMed

    Qi, Xue-Lian; Elworthy, Anthony C; Lambert, Bryce C; Constantinidis, Christos

    2015-01-01

    Both dorsolateral prefrontal and posterior parietal cortex have been implicated in spatial working memory and representation of task information. Prior experiments training animals to recall the first of a sequence of stimuli and examining the effect of subsequent distractors have identified increased ability of the prefrontal cortex to represent remembered stimuli and filter distractors. It is unclear, however, if this prefrontal functional specialization extends to stimuli appearing earlier in a sequence, when subjects are cued to remember subsequent ones. It is also not known how task information interacts with persistent activity representing remembered stimuli and distractors in the two areas. To address these questions, we trained monkeys to remember either the first or second of two stimuli presented in sequence and recorded neuronal activity from the posterior parietal and dorsolateral prefrontal cortex. The prefrontal cortex was better able to represent the actively remembered stimulus, whereas the posterior parietal cortex was more modulated by distractors; however, task effects interfered with this representation. As a result, large proportions of neurons with persistent activity and task effects exhibited a preference for a stimulus when it appeared as a distractor in both areas. Additionally, prefrontal neurons were modulated to a greater extent by task factors during the delay period of the task. The results indicate that the prefrontal cortex is better able than the posterior parietal cortex to differentiate between distractors and actively remembered stimuli and is more modulated by the task; however, this relative preference is highly context dependent and depends on the specific requirements of the task. PMID:25298389

  19. Distinct parietal sites mediate the influences of mood, arousal, and their interaction on human recognition memory.

    PubMed

    Greene, Ciara M; Flannery, Oliver; Soto, David

    2014-12-01

    The two dimensions of emotion, mood valence and arousal, have independent effects on recognition memory. At present, however, it is not clear how those effects are reflected in the human brain. Previous research in this area has generally dealt with memory for emotionally valenced or arousing stimuli, but the manner in which interacting mood and arousal states modulate responses in memory substrates remains poorly understood. We investigated memory for emotionally neutral items while independently manipulating mood valence and arousal state by means of music exposure. Four emotional conditions were created: positive mood/high arousal, positive mood/low arousal, negative mood/high arousal, and negative mood/low arousal. We observed distinct effects of mood valence and arousal in parietal substrates of recognition memory. Positive mood increased activity in ventral posterior parietal cortex (PPC) and orbitofrontal cortex, whereas arousal condition modulated activity in dorsal PPC and the posterior cingulate. An interaction between valence and arousal was observed in left ventral PPC, notably in a parietal area distinct from the those identified for the main effects, with a stronger effect of mood on recognition memory responses here under conditions of relative high versus low arousal. We interpreted the PPC activations in terms of the attention-to-memory hypothesis: Increased arousal may lead to increased top-down control of memory, and hence dorsal PPC activation, whereas positive mood valence may result in increased activity in ventral PPC regions associated with bottom-up attention to memory. These findings indicate that distinct parietal sites mediate the influences of mood, arousal, and their interplay during recognition memory.

  20. Potential mediation of prostaglandin E2 release from isolated human parietal cells by protein kinase C.

    PubMed

    Schepp, W; Schneider, J; Tatge, C; Schusdziarra, V; Classen, M

    1990-01-01

    Parietal cells are a major source of gastric mucosal prostaglandins in various species. We examined cholinergic stimulation of prostaglandin E2 (PGE2) release from human parietal cells; using activators of the protein kinase C we attempted to get an indirect insight into cellular mechanisms which control PGE2 release. Gastric mucosal specimens were obtained at surgery and the cells were dispersed by collagenase and pronase E. Parietal cells were enriched to 65-80% by a Percoll gradient, and were incubated for 30 min. PGE2 release into the medium (radioimmunoassay) was 74-126 pg/10(6) cells/30 min under basal conditions and was 2.6-fold increased by carbachol (10(-5) and 10(-4) M). Similarly, PGE2 release was stimulated by phospholipase C (20-200 mU/ml, 364% above basal), 1-oleoyl-2-acetyl-sn-glycerol (10(-9)-10(-5) M, 229%), 12-O-tetradecanoylphorbol-13-acetate (TPA; 10(-9)-10(-5) M, 283%) and calcium ionophore A23187 (10(-7)-10(-5) M, 219%). Simultaneous presence of A23187 and TPA synergistically induced stimulation which was slightly higher than the sum of the individual responses. N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide W-7, a putative calmodulin antagonist, inhibited TPA-induced PGE2 release at concentrations regarded specific for blocking calmodulin (IC50 = 1.5 X 0(-6) M). We conclude that in human parietal cells PGE2 is released upon cholinergic stimulation and that phospholipase C and protein kinase C are involved in the control of PGE2 release. We speculate that calmodulin might interact with a protein phosphorylated by protein kinase C to cause PGE2 release.

  1. Thematic role assignment in the posterior parietal cortex: A TMS study.

    PubMed

    Finocchiaro, Chiara; Capasso, Rita; Cattaneo, Luigi; Zuanazzi, Arianna; Miceli, Gabriele

    2015-10-01

    Verbs denote relations between entities acting a role in an event. Thematic roles are essential to the correct use of verbs and involve both semantic and syntactic aspects. We used repetitive Transcranial Magnetic Stimulation (rTMS) to study the involvement of three different left parietal sites in the understanding of thematic roles. In a sentence-to-picture matching task, twelve participants were asked to judge whether or not a given picture matched with a written sentence. Pictures represented simple reversible actions, and sentences were in the active or passive diathesis. Whereas both active and passive sentences require the correct encoding of thematic roles, passives also imply thematic reanalysis, as the canonical order of thematic roles is systematically reversed. The experiment was divided in three sessions. In each session a different parietal site (anterior, middle, posterior) was stimulated at 5 Hz in an event-related fashion, time-locked to the presentation of visual stimuli. Results showed increased accuracy for passive sentences following posterior parietal stimulation. The effect appeared to be (a) TMS-related, as no effect was observed in a control, no-TMS experiment with eighteen new participants; (b) independent from semantic processes involved in word-picture association, as no TMS-related effects were observed in a picture-word matching task. We interpret the results as showing that the posterior parietal site is specifically involved in the assignment of thematic roles, in particular when the correct interpretation of a sentence requires reanalysis of temporarily encoded thematic roles, as in passive reversible sentences.

  2. A case of granulomatous hypophysitis with hypopituitarism and minimal pituitary enlargement.

    PubMed Central

    Hassoun, P; Anayssi, E; Salti, I

    1985-01-01

    A case of hypopituitarism and minimal sellar enlargement was found at hypophysectomy to have a giant cell granuloma of the pituitary. The clinical and histopathological features of this rare entity are reviewed. It is proposed that hypopituitarism which is out of proportion to minimal sellar enlargement may be a suggestive clue to the preoperative diagnosis of giant cell granulous which normally simulates a pituitary tumour. Images PMID:4045491

  3. Differential roles of the dorsal prefrontal and posterior parietal cortices in visual search: a TMS study.

    PubMed

    Yan, Yulong; Wei, Rizhen; Zhang, Qian; Jin, Zhenlan; Li, Ling

    2016-01-01

    Although previous studies have shown that fronto-parietal attentional networks play a crucial role in bottom-up and top-down processes, the relative contribution of the frontal and parietal cortices to these processes remains elusive. Here we used transcranial magnetic stimulation (TMS) to interfere with the activity of the right dorsal prefrontal cortex (DLPFC) or the right posterior parietal cortex (PPC), immediately prior to the onset of the visual search display. Participants searched a target defined by color and orientation in "pop-out" or "search" condition. Repetitive TMS was applied to either the right DLPFC or the right PPC on different days. Performance was evaluated at baseline (no TMS), during TMS, and after TMS (Post-session). RTs were prolonged when TMS was applied over the DLPFC in the search, but not in the pop-out condition, relative to the baseline session. In comparison, TMS over the PPC prolonged RTs in the pop-out condition, and when the target appeared in the left visual field for the search condition. Taken together these findings provide evidence for a differential role of DLPFC and PPC in the visual search, indicating that DLPFC has a specific involvement in the "search" condition, while PPC is mainly involved in detecting "pop-out" targets. PMID:27452715

  4. Drug-resistant parietal epilepsy: polymorphic ictal semiology does not preclude good post-surgical outcome.

    PubMed

    Francione, Stefano; Liava, Alexandra; Mai, Roberto; Nobili, Lino; Sartori, Ivana; Tassi, Laura; Scarpa, Pina; Cardinale, Francesco; Castana, Laura; Cossu, Massimo; Lo Russo, Giorgio

    2015-03-01

    We investigated the anatomo-electro-clinical features and clinical outcome of surgical resections strictly confined to the parietal lobe in 40 consecutive patients who received surgery for pharmacoresistant seizures. The population was subcategorized into a paediatric (11 subjects; mean age at surgery: 7.2+/-3.7 years) and an adult group (29 patients; mean age at surgery: 30+/-10.8 years). The paediatric group more frequently exhibited personal antecedents, neurological impairment, high seizure frequency, and dysplastic lesions. Nonetheless, compared with adults, children had better outcome and more frequently reached definitive drug discontinuation after surgery. After a mean follow-up of 9.4 years (range: 3.1-16.7), 30 subjects (75%) were classified as Engel Class I. The presence of multiple types of aura in the same patient, as well as a high incidence of secondary generalization, represented a characteristic feature of parietal seizures and did not correlate negatively with surgical outcome. A total resection of the epileptogenic zone and a localizing/regional interictal EEG were statistically significant predictive factors of outcome. Intracerebral investigation, performed in 55% of cases, contributed to complete tailored resections of the epileptogenic area and determination of prognosis. Frequent subjective manifestations of parietal lobe seizures, such as vertiginous, cephalic and visual-moving sensations, underscore their potential misdiagnosis as non-epileptic events.

  5. Measurements of evoked electroencephalograph by transcranial magnetic stimulation applied to motor cortex and posterior parietal cortex

    NASA Astrophysics Data System (ADS)

    Iwahashi, Masakuni; Koyama, Yohei; Hyodo, Akira; Hayami, Takehito; Ueno, Shoogo; Iramina, Keiji

    2009-04-01

    To investigate the functional connectivity, the evoked potentials by stimulating at the motor cortex, the posterior parietal cortex, and the cerebellum by transcranial magnetic stimulation (TMS) were measured. It is difficult to measure the evoked electroencephalograph (EEG) by the magnetic stimulation because of the large artifact induced by the magnetic pulse. We used an EEG measurement system with sample-and-hold circuit and an independent component analysis to eliminate the electromagnetic interaction emitted from TMS. It was possible to measure EEG signals from all electrodes over the head within 10 ms after applying the TMS. When the motor area was stimulated by TMS, the spread of evoked electrical activity to the contralateral hemisphere was observed at 20 ms after stimulation. However, when the posterior parietal cortex was stimulated, the evoked electrical activity to the contralateral hemisphere was not observed. When the cerebellum was stimulated, the cortical activity propagated from the stimulated point to the frontal area and the contralateral hemisphere at around 20 ms after stimulation. These results suggest that the motor area has a strong interhemispheric connection and the posterior parietal cortex has no interhemispheric connection.

  6. Fronto-parietal regulation of media violence exposure in adolescents: a multi-method study

    PubMed Central

    Strenziok, Maren; Krueger, Frank; Deshpande, Gopikrishna; Lenroot, Rhoshel K.; van der Meer, Elke

    2011-01-01

    Adolescents spend a significant part of their leisure time watching TV programs and movies that portray violence. It is unknown, however, how the extent of violent media use and the severity of aggression displayed affect adolescents’ brain function. We investigated skin conductance responses, brain activation and functional brain connectivity to media violence in healthy adolescents. In an event-related functional magnetic resonance imaging experiment, subjects repeatedly viewed normed videos that displayed different degrees of aggressive behavior. We found a downward linear adaptation in skin conductance responses with increasing aggression and desensitization towards more aggressive videos. Our results further revealed adaptation in a fronto-parietal network including the left lateral orbitofrontal cortex (lOFC), right precuneus and bilateral inferior parietal lobules, again showing downward linear adaptations and desensitization towards more aggressive videos. Granger causality mapping analyses revealed attenuation in the left lOFC, indicating that activation during viewing aggressive media is driven by input from parietal regions that decreased over time, for more aggressive videos. We conclude that aggressive media activates an emotion–attention network that has the capability to blunt emotional responses through reduced attention with repeated viewing of aggressive media contents, which may restrict the linking of the consequences of aggression with an emotional response, and therefore potentially promotes aggressive attitudes and behavior. PMID:20934985

  7. Fronto-parietal regulation of media violence exposure in adolescents: a multi-method study.

    PubMed

    Strenziok, Maren; Krueger, Frank; Deshpande, Gopikrishna; Lenroot, Rhoshel K; van der Meer, Elke; Grafman, Jordan

    2011-10-01

    Adolescents spend a significant part of their leisure time watching TV programs and movies that portray violence. It is unknown, however, how the extent of violent media use and the severity of aggression displayed affect adolescents' brain function. We investigated skin conductance responses, brain activation and functional brain connectivity to media violence in healthy adolescents. In an event-related functional magnetic resonance imaging experiment, subjects repeatedly viewed normed videos that displayed different degrees of aggressive behavior. We found a downward linear adaptation in skin conductance responses with increasing aggression and desensitization towards more aggressive videos. Our results further revealed adaptation in a fronto-parietal network including the left lateral orbitofrontal cortex (lOFC), right precuneus and bilateral inferior parietal lobules, again showing downward linear adaptations and desensitization towards more aggressive videos. Granger causality mapping analyses revealed attenuation in the left lOFC, indicating that activation during viewing aggressive media is driven by input from parietal regions that decreased over time, for more aggressive videos. We conclude that aggressive media activates an emotion-attention network that has the capability to blunt emotional responses through reduced attention with repeated viewing of aggressive media contents, which may restrict the linking of the consequences of aggression with an emotional response, and therefore potentially promotes aggressive attitudes and behavior. PMID:20934985

  8. Differential roles of the dorsal prefrontal and posterior parietal cortices in visual search: a TMS study.

    PubMed

    Yan, Yulong; Wei, Rizhen; Zhang, Qian; Jin, Zhenlan; Li, Ling

    2016-07-25

    Although previous studies have shown that fronto-parietal attentional networks play a crucial role in bottom-up and top-down processes, the relative contribution of the frontal and parietal cortices to these processes remains elusive. Here we used transcranial magnetic stimulation (TMS) to interfere with the activity of the right dorsal prefrontal cortex (DLPFC) or the right posterior parietal cortex (PPC), immediately prior to the onset of the visual search display. Participants searched a target defined by color and orientation in "pop-out" or "search" condition. Repetitive TMS was applied to either the right DLPFC or the right PPC on different days. Performance was evaluated at baseline (no TMS), during TMS, and after TMS (Post-session). RTs were prolonged when TMS was applied over the DLPFC in the search, but not in the pop-out condition, relative to the baseline session. In comparison, TMS over the PPC prolonged RTs in the pop-out condition, and when the target appeared in the left visual field for the search condition. Taken together these findings provide evidence for a differential role of DLPFC and PPC in the visual search, indicating that DLPFC has a specific involvement in the "search" condition, while PPC is mainly involved in detecting "pop-out" targets.

  9. Differential roles of the dorsal prefrontal and posterior parietal cortices in visual search: a TMS study

    PubMed Central

    Yan, Yulong; Wei, Rizhen; Zhang, Qian; Jin, Zhenlan; Li, Ling

    2016-01-01

    Although previous studies have shown that fronto-parietal attentional networks play a crucial role in bottom-up and top-down processes, the relative contribution of the frontal and parietal cortices to these processes remains elusive. Here we used transcranial magnetic stimulation (TMS) to interfere with the activity of the right dorsal prefrontal cortex (DLPFC) or the right posterior parietal cortex (PPC), immediately prior to the onset of the visual search display. Participants searched a target defined by color and orientation in “pop-out” or “search” condition. Repetitive TMS was applied to either the right DLPFC or the right PPC on different days. Performance was evaluated at baseline (no TMS), during TMS, and after TMS (Post-session). RTs were prolonged when TMS was applied over the DLPFC in the search, but not in the pop-out condition, relative to the baseline session. In comparison, TMS over the PPC prolonged RTs in the pop-out condition, and when the target appeared in the left visual field for the search condition. Taken together these findings provide evidence for a differential role of DLPFC and PPC in the visual search, indicating that DLPFC has a specific involvement in the “search” condition, while PPC is mainly involved in detecting “pop-out” targets. PMID:27452715

  10. Fronto-parietal regulation of media violence exposure in adolescents: a multi-method study.

    PubMed

    Strenziok, Maren; Krueger, Frank; Deshpande, Gopikrishna; Lenroot, Rhoshel K; van der Meer, Elke; Grafman, Jordan

    2011-10-01

    Adolescents spend a significant part of their leisure time watching TV programs and movies that portray violence. It is unknown, however, how the extent of violent media use and the severity of aggression displayed affect adolescents' brain function. We investigated skin conductance responses, brain activation and functional brain connectivity to media violence in healthy adolescents. In an event-related functional magnetic resonance imaging experiment, subjects repeatedly viewed normed videos that displayed different degrees of aggressive behavior. We found a downward linear adaptation in skin conductance responses with increasing aggression and desensitization towards more aggressive videos. Our results further revealed adaptation in a fronto-parietal network including the left lateral orbitofrontal cortex (lOFC), right precuneus and bilateral inferior parietal lobules, again showing downward linear adaptations and desensitization towards more aggressive videos. Granger causality mapping analyses revealed attenuation in the left lOFC, indicating that activation during viewing aggressive media is driven by input from parietal regions that decreased over time, for more aggressive videos. We conclude that aggressive media activates an emotion-attention network that has the capability to blunt emotional responses through reduced attention with repeated viewing of aggressive media contents, which may restrict the linking of the consequences of aggression with an emotional response, and therefore potentially promotes aggressive attitudes and behavior.

  11. Asymmetric Multisensory Interactions of Visual and Somatosensory Responses in a Region of the Rat Parietal Cortex

    PubMed Central

    Lippert, Michael T.; Takagaki, Kentaroh

    2013-01-01

    Perception greatly benefits from integrating multiple sensory cues into a unified percept. To study the neural mechanisms of sensory integration, model systems are required that allow the simultaneous assessment of activity and the use of techniques to affect individual neural processes in behaving animals. While rodents qualify for these requirements, little is known about multisensory integration and areas involved for this purpose in the rodent. Using optical imaging combined with laminar electrophysiological recordings, the rat parietal cortex was identified as an area where visual and somatosensory inputs converge and interact. Our results reveal similar response patterns to visual and somatosensory stimuli at the level of current source density (CSD) responses and multi-unit responses within a strip in parietal cortex. Surprisingly, a selective asymmetry was observed in multisensory interactions: when the somatosensory response preceded the visual response, supra-linear summation of CSD was observed, but the reverse stimulus order resulted in sub-linear effects in the CSD. This asymmetry was not present in multi-unit activity however, which showed consistently sub-linear interactions. These interactions were restricted to a specific temporal window, and pharmacological tests revealed significant local intra-cortical contributions to this phenomenon. Our results highlight the rodent parietal cortex as a system to model the neural underpinnings of multisensory processing in behaving animals and at the cellular level. PMID:23667650

  12. Optical imaging of visually guided reaching in macaque posterior parietal cortex.

    PubMed

    Heider, Barbara; Siegel, Ralph M

    2014-03-01

    Sensorimotor transformation for reaching movements in primates requires a large network of visual, parietal, and frontal cortical areas. We performed intrinsic optical imaging over posterior parietal cortex including areas 7a and the dorsal perilunate in macaque monkeys during visually guided hand movements. Reaching was performed while foveating one of nine static reach targets; thus eye-position-varied concurrently with reach position. The hemodynamic reflectance signal was analyzed during specific phases of the task including pre-reach, reach, and touch epochs. The eye position maps changed substantially as the task progressed: First, direction of spatial tuning shifted from a weak preference close to the center to the lower eye positions in both cortical areas. Overall tuning strength was greater in area 7a. Second, strength of spatial tuning increased from the early pre-reach to the later touch epoch. These consistent temporal changes suggest that dynamic properties of the reflectance signal were modulated by task parameters. The peak amplitude and peak delay of the reflectance signal showed considerable differences between eye position but were similar between areas. Compared with a detection task using a lever response, the reach task yielded higher amplitudes and longer delays. These findings demonstrate a spatially tuned topographical representation for reaching in both areas and suggest a strong synergistic combination of various feedback signals that result in a spatially tuned amplification of the hemodynamic response in posterior parietal cortex.

  13. Longitudinal working memory development is related to structural maturation of frontal and parietal cortices.

    PubMed

    Tamnes, Christian K; Walhovd, Kristine B; Grydeland, Håkon; Holland, Dominic; Østby, Ylva; Dale, Anders M; Fjell, Anders M

    2013-10-01

    Parallels between patterns of brain maturation and cognitive development have been observed repeatedly, but studies directly testing the relationships between improvements in specific cognitive functions and structural changes in the brain are lacking. Working memory development extends throughout childhood and adolescence and likely plays a central role for cognitive development in multiple domains and in several neurodevelopmental disorders. Neuroimaging, lesion, and electrophysiological studies indicate that working memory emerges from coordinated interactions of a distributed neural network in which fronto-parietal cortical regions are critical. In the current study, verbal working memory function, as indexed by performance on the Keep Track task, and volumes of brain regions were assessed at two time points in 79 healthy children and adolescents in the age range of 8-22 years. Longitudinal change in cortical and subcortical volumes was quantified by the use of Quantitative Anatomical Regional Change. Improvement in working memory was related to cortical volume reduction in bilateral prefrontal and posterior parietal regions and in regions around the central sulci. Importantly, these relationships were not explained by differences in gender, age, or intelligence level or change in intellectual abilities. Furthermore, the relationships did not interact with age and were not significantly different in children, young adolescents, and old adolescents. The results provide the first direct evidence that structural maturation of a fronto-parietal cortical network supports working memory development. PMID:23767921

  14. Preferential encoding of visual categories in parietal cortex compared with prefrontal cortex.

    PubMed

    Swaminathan, Sruthi K; Freedman, David J

    2012-02-01

    The ability to recognize the behavioral relevance, or category membership, of sensory stimuli is critical for interpreting the meaning of events in our environment. Neurophysiological studies of visual categorization have found categorical representations of stimuli in prefrontal cortex (PFC), an area that is closely associated with cognitive and executive functions. Recent studies have also identified neuronal category signals in parietal areas that are typically associated with visual-spatial processing. It has been proposed that category-related signals in parietal cortex and other visual areas may result from 'top-down' feedback from PFC. We directly compared neuronal activity in the lateral intraparietal (LIP) area and PFC in monkeys performing a visual motion categorization task. We found that LIP showed stronger, more reliable and shorter latency category signals than PFC. These findings suggest that LIP is strongly involved in visual categorization and argue against the idea that parietal category signals arise as a result of feedback from PFC during this task. PMID:22246435

  15. Methods of artificial enlargement of the training set for statistical shape models.

    PubMed

    Koikkalainen, Juha; Tölli, Tuomas; Lauerma, Kirsi; Antila, Kari; Mattila, Elina; Lilja, Mikko; Lötjönen, Jyrki

    2008-11-01

    Due to the small size of training sets, statistical shape models often over-constrain the deformation in medical image segmentation. Hence, artificial enlargement of the training set has been proposed as a solution for the problem to increase the flexibility of the models. In this paper, different methods were evaluated to artificially enlarge a training set. Furthermore, the objectives were to study the effects of the size of the training set, to estimate the optimal number of deformation modes, to study the effects of different error sources, and to compare different deformation methods. The study was performed for a cardiac shape model consisting of ventricles, atria, and epicardium, and built from magnetic resonance (MR) volume images of 25 subjects. Both shape modeling and image segmentation accuracies were studied. The objectives were reached by utilizing different training sets and datasets, and two deformation methods. The evaluation proved that artificial enlargement of the training set improves both the modeling and segmentation accuracy. All but one enlargement techniques gave statistically significantly (p < 0.05) better segmentation results than the standard method without enlargement. The two best enlargement techniques were the nonrigid movement technique and the technique that combines principal component analysis (PCA) and finite element model (FEM). The optimal number of deformation modes was found to be near 100 modes in our application. The active shape model segmentation gave better segmentation accuracy than the one based on the simulated annealing optimization of the model weights.

  16. Refuting the hypothesis that a unilateral human parietal lesion abolishes saccade corollary discharge.

    PubMed

    Rath-Wilson, Kate; Guitton, Daniel

    2015-12-01

    This paper questions the prominent role that the parietal lobe is thought to play in the processing of corollary discharges for saccadic eye movements. A corollary discharge copies the motor neurons' signal and sends it to brain areas involved in monitoring eye trajectories. The classic double-step saccade task has been used extensively to study these mechanisms: two targets (T1 and T2) are quickly (40-150 ms) flashed sequentially in the periphery. After the extinction of the fixation point, subjects are to make two saccades (S1 and S2), in the dark, to the remembered locations of the targets in the order they appeared. The success of S2 requires a corollary discharge encoding S1's vector. Patients with a parietal lobe lesion, particularly on the right, are impaired at generating an accurate S2 when S1 is directed contralesionally, but not ipsilesionally, thought due to an impaired contralesional corollary discharge. In contrast, we hypothesize that failure on the classic double-step task is due to visual processing and attentional deficits that commonly result from lesions of the parietal lobe and imperfect data analysis methods. Here, we studied parietal patients who fail in the classic double-step task when tested and data analysed according to previously published methods. We then tested our patients on two modified versions of the double-step task, designed to mitigate deficits other than corollary discharge that may have confounded previous investigations. In our 'exogenous' task, T2 was presented prior to T1 and for longer (T2: 800-1200 ms, T1: 350 ms) than in the classic task. S1 went to T1 and S2 to T2, all in the dark. All patients who completed sufficient trials had a corollary discharge for contralesional and ipsilesional S1s (5/5). In our 'endogenous' task, a single target was presented peripherally for 800-1200 ms. After extinction of target and fixation point, patients made first an 'endogenous' S1, of self-determined amplitude either to the left or

  17. Right Ventricular Enlargement within Months of Arteriovenous Fistula Creation in 2 Hemodialysis Patients.

    PubMed

    Ragupathi, Loheetha; Johnson, Drew; Marhefka, Gregary D

    2016-08-01

    Surgically created arteriovenous fistulae (AVF) for hemodialysis can contribute to hemodynamic changes. We describe the cases of 2 male patients in whom new right ventricular enlargement developed after an AVF was created for hemodialysis. Patient 1 sustained high-output heart failure solely attributable to the AVF. After AVF banding and subsequent ligation, his heart failure and right ventricular enlargement resolved. In Patient 2, the AVF contributed to new-onset right ventricular enlargement, heart failure, and ascites. His severe pulmonary hypertension was caused by diastolic heart failure, diabetes mellitus, and obstructive sleep apnea. His right ventricular enlargement and heart failure symptoms did not improve after AVF ligation. We think that our report is the first to specifically correlate the echocardiographic finding of right ventricular enlargement with AVF sequelae. Clinicians who treat end-stage renal disease patients should be aware of this potential sequela of AVF creation, particularly in the upper arm. We recommend obtaining preoperative echocardiograms in all patients who will undergo upper-arm AVF creation, so that comparisons can be made postoperatively. Alternative consideration should be given to creating the AVF in the radial artery, because of less shunting and therefore less potential for right-sided heart failure and pulmonary hypertension. A multidisciplinary approach is optimal when selecting patients for AVF banding or ligation.

  18. Capsule enlargement in Cryptococcus neoformans confers resistance to oxidative stress suggesting a mechanism for intracellular survival.

    PubMed

    Zaragoza, Oscar; Chrisman, Cara J; Castelli, Maria Victoria; Frases, Susana; Cuenca-Estrella, Manuel; Rodríguez-Tudela, Juan Luis; Casadevall, Arturo

    2008-10-01

    Cryptococcus neoformans is a facultative intracellular pathogen. The most distinctive feature of C. neoformans is a polysaccharide capsule that enlarges depending on environmental stimuli. The mechanism by which C. neoformans avoids killing during phagocytosis is unknown. We hypothesized that capsule growth conferred resistance to microbicidal molecules produced by the host during infection, particularly during phagocytosis. We observed that capsule enlargement conferred resistance to reactive oxygen species produced by H(2)O(2) that was not associated with a higher catalase activity, suggesting a new function for the capsule as a scavenger of reactive oxidative intermediates. Soluble capsular polysaccharide protected C. neoformans and Saccharomyces cerevisiae from killing by H(2)O(2). Acapsular mutants had higher susceptibility to free radicals. Capsular polysaccharide acted as an antioxidant in the nitroblue tetrazolium (NBT) reduction coupled to beta-nicotinamide adenine dinucleotide (NADH)/phenazine methosulfate (PMS) assay. Capsule enlargement conferred resistance to antimicrobial peptides and the antifungal drug Amphotericin B. Interestingly, the capsule had no effect on susceptibility to azoles and increased susceptibility to fluconazole. Capsule enlargement reduced phagocytosis by environmental predators, although we also noticed that in this system, starvation of C. neoformans cells produced resistance to phagocytosis. Our results suggest that capsular enlargement is a mechanism that enhances C. neoformans survival when ingested by phagocytic cells.

  19. Capsule enlargement in Cryptococcus neoformans confers resistance to oxidative stress suggesting a mechanism for intracellular survival

    PubMed Central

    Zaragoza, Oscar; Chrisman, Cara J.; Castelli, Maria Victoria; Frases, Susana; Cuenca-Estrella, Manuel; Rodríguez-Tudela, Juan Luis; Casadevall, Arturo

    2015-01-01

    Summary Cryptococcus neoformans is a facultative intracellular pathogen. The most distinctive feature of C. neoformans is a polysaccharide capsule that enlarges depending on environmental stimuli. The mechanism by which C. neoformans avoids killing during phagocytosis is unknown. We hypothesized that capsule growth conferred resistance to microbicidal molecules produced by the host during infection, particularly during phagocytosis. We observed that capsule enlargement conferred resistance to reactive oxygen species produced by H2O2 that was not associated with a higher catalase activity, suggesting a new function for the capsule as a scavenger of reactive oxidative intermediates. Soluble capsular polysaccharide protected C. neoformans and Saccharomyces cerevisiae from killing by H2O2. Acapsular mutants had higher susceptibility to free radicals. Capsular polysaccharide acted as an antioxidant in the nitroblue tetrazolium (NBT) reduction coupled to β-nicotinamide adenine dinucleotide (NADH)/phenazine methosulfate (PMS) assay. Capsule enlargement conferred resistance to antimicrobial peptides and the antifungal drug Amphotericin B. Interestingly, the capsule had no effect on susceptibility to azoles and increased susceptibility to fluconazole. Capsule enlargement reduced phagocytosis by environmental predators, although we also noticed that in this system, starvation of C. neoformans cells produced resistance to phagocytosis. Our results suggest that capsular enlargement is a mechanism that enhances C. neoformans survival when ingested by phagocytic cells. PMID:18554313

  20. Right Ventricular Enlargement within Months of Arteriovenous Fistula Creation in 2 Hemodialysis Patients.

    PubMed

    Ragupathi, Loheetha; Johnson, Drew; Marhefka, Gregary D

    2016-08-01

    Surgically created arteriovenous fistulae (AVF) for hemodialysis can contribute to hemodynamic changes. We describe the cases of 2 male patients in whom new right ventricular enlargement developed after an AVF was created for hemodialysis. Patient 1 sustained high-output heart failure solely attributable to the AVF. After AVF banding and subsequent ligation, his heart failure and right ventricular enlargement resolved. In Patient 2, the AVF contributed to new-onset right ventricular enlargement, heart failure, and ascites. His severe pulmonary hypertension was caused by diastolic heart failure, diabetes mellitus, and obstructive sleep apnea. His right ventricular enlargement and heart failure symptoms did not improve after AVF ligation. We think that our report is the first to specifically correlate the echocardiographic finding of right ventricular enlargement with AVF sequelae. Clinicians who treat end-stage renal disease patients should be aware of this potential sequela of AVF creation, particularly in the upper arm. We recommend obtaining preoperative echocardiograms in all patients who will undergo upper-arm AVF creation, so that comparisons can be made postoperatively. Alternative consideration should be given to creating the AVF in the radial artery, because of less shunting and therefore less potential for right-sided heart failure and pulmonary hypertension. A multidisciplinary approach is optimal when selecting patients for AVF banding or ligation. PMID:27547150

  1. Right Ventricular Enlargement within Months of Arteriovenous Fistula Creation in 2 Hemodialysis Patients

    PubMed Central

    Ragupathi, Loheetha; Johnson, Drew

    2016-01-01

    Surgically created arteriovenous fistulae (AVF) for hemodialysis can contribute to hemodynamic changes. We describe the cases of 2 male patients in whom new right ventricular enlargement developed after an AVF was created for hemodialysis. Patient 1 sustained high-output heart failure solely attributable to the AVF. After AVF banding and subsequent ligation, his heart failure and right ventricular enlargement resolved. In Patient 2, the AVF contributed to new-onset right ventricular enlargement, heart failure, and ascites. His severe pulmonary hypertension was caused by diastolic heart failure, diabetes mellitus, and obstructive sleep apnea. His right ventricular enlargement and heart failure symptoms did not improve after AVF ligation. We think that our report is the first to specifically correlate the echocardiographic finding of right ventricular enlargement with AVF sequelae. Clinicians who treat end-stage renal disease patients should be aware of this potential sequela of AVF creation, particularly in the upper arm. We recommend obtaining preoperative echocardiograms in all patients who will undergo upper-arm AVF creation, so that comparisons can be made postoperatively. Alternative consideration should be given to creating the AVF in the radial artery, because of less shunting and therefore less potential for right-sided heart failure and pulmonary hypertension. A multidisciplinary approach is optimal when selecting patients for AVF banding or ligation. PMID:27547150

  2. Dissociable effects of surprise and model update in parietal and anterior cingulate cortex.

    PubMed

    O'Reilly, Jill X; Schüffelgen, Urs; Cuell, Steven F; Behrens, Timothy E J; Mars, Rogier B; Rushworth, Matthew F S

    2013-09-17

    Brains use predictive models to facilitate the processing of expected stimuli or planned actions. Under a predictive model, surprising (low probability) stimuli or actions necessitate the immediate reallocation of processing resources, but they can also signal the need to update the underlying predictive model to reflect changes in the environment. Surprise and updating are often correlated in experimental paradigms but are, in fact, distinct constructs that can be formally defined as the Shannon information (IS) and Kullback-Leibler divergence (DKL) associated with an observation. In a saccadic planning task, we observed that distinct behaviors and brain regions are associated with surprise/IS and updating/DKL. Although surprise/IS was associated with behavioral reprogramming as indexed by slower reaction times, as well as with activity in the posterior parietal cortex [human lateral intraparietal area (LIP)], the anterior cingulate cortex (ACC) was specifically activated during updating of the predictive model (DKL). A second saccade-sensitive region in the inferior posterior parietal cortex (human 7a), which has connections to both LIP and ACC, was activated by surprise and modulated by updating. Pupillometry revealed a further dissociation between surprise and updating with an early positive effect of surprise and late negative effect of updating on pupil area. These results give a computational account of the roles of the ACC and two parietal saccade regions, LIP and 7a, by which their involvement in diverse tasks can be understood mechanistically. The dissociation of functional roles between regions within the reorienting/reprogramming network may also inform models of neurological phenomena, such as extinction and Balint syndrome, and neglect.

  3. Apical vacuole formation by gastric parietal cells in primary culture: effect of low extracellular Ca2+

    PubMed Central

    Nakada, Stephanie L.; Machen, Terry E.; Forte, John G.

    2012-01-01

    In primary culture, the gastric parietal cell's deeply invaginated apical membrane, seen in microscopy by phalloidin binding to F-actin (concentrated in microvilli and a subapical web), is engulfed into the cell, separated from the basolateral membrane (which then becomes the complete plasma membrane), and converted, from a lacy interconnected system of canaliculi, into several separate vacuoles. In this study, vacuolar morphology was achieved by 71% of parietal cells 8 h after typical collagenase digestion of rabbit gastric mucosa, but the tight-junctional protein zonula occludens-1 (ZO-1) was completely delocalized after ∼2 h, when cells were ready for culturing. Use of low-Ca2+ medium (4 mM EGTA) to release cells quickly from gastric glands yielded parietal cells in which ZO-1 was seen in a small spot or ring, a localization quickly lost if these cells were then cultured in normal Ca2+ but remaining up to 20 h if they were cultured in low Ca2+. The cells in low Ca2+ mostly retained, at 20 h, an intermediate morphology of many bulbous canalicular expansions (“prevacuoles”), seemingly with narrow interconnections. Histamine stimulation of 20-h cells with intermediate morphology caused colocalization of proton-pumping H-K-ATPase with canaliculi and prevacuoles but little swelling of those structures, consistent with a remaining apical pore through which secreted acid could escape. Apparent canalicular interconnections, lack of stimulated swelling, and lingering ZO-1 staining indicate inhibition of membrane fission processes that separate apical from basolateral membrane and vacuoles from each other, suggesting an important role for extracellular Ca2+ in these, and possibly other, endocytotic processes. PMID:23099641

  4. Developmental improvements in voluntary control of behavior: effect of preparation in the fronto-parietal network?

    PubMed

    Alahyane, Nadia; Brien, Donald C; Coe, Brian C; Stroman, Patrick W; Munoz, Douglas P

    2014-09-01

    The ability to prepare for an action improves the speed and accuracy of its performance. While many studies indicate that behavior performance continues to improve throughout childhood and adolescence, it remains unclear whether or how preparatory processes change with development. Here, we used a rapid event-related fMRI design in three age groups (8-12, 13-17, 18-25years) who were instructed to execute either a prosaccade (look toward peripheral target) or an antisaccade (look away from target) task. We compared brain activity within the core fronto-parietal network involved in saccade control at two epochs of saccade generation: saccade preparation related to task instruction versus saccade execution related to target appearance. The inclusion of catch trials containing only task instruction and no target or saccade response allowed us to isolate saccade preparation from saccade execution. Five regions of interest were selected: the frontal, supplementary, parietal eye fields which are consistently recruited during saccade generation, and two regions involved in top down executive control: the dorsolateral prefrontal and anterior cingulate cortices. Our results showed strong evidence that developmental improvements in saccade performance were related to better saccade preparation rather than saccade execution. These developmental differences were mostly attributable to children who showed reduced fronto-parietal activity during prosaccade and antisaccade preparation, along with longer saccade reaction times and more incorrect responses, compared to adolescents and adults. The dorsolateral prefrontal cortex was engaged similarly across age groups, suggesting a general role in maintaining task instructions through the whole experiment. Overall, these findings suggest that developmental improvements in behavioral control are supported by improvements in effectively presetting goal-appropriate brain systems.

  5. Motor imagery-based skill acquisition disrupted following rTMS of the inferior parietal lobule.

    PubMed

    Kraeutner, Sarah N; Keeler, Laura T; Boe, Shaun G

    2016-02-01

    Motor imagery (MI), the mental rehearsal of motor tasks, has promise as a therapy in post-stroke rehabilitation. The potential effectiveness of MI is attributed to the facilitation of plasticity in numerous brain regions akin to those recruited for physical practice. It is suggested, however, that MI relies more heavily on regions commonly affected post-stroke, including left hemisphere parietal regions involved in visuospatial processes. However, the impact of parietal damage on MI-based skill acquisition that underlies rehabilitation remains unclear. Here, we examine the contribution of the left inferior parietal lobule (IPL) to MI using inhibitory transcranial magnetic stimulation (TMS) and an MI-based implicit sequence learning (ISL) paradigm. Participants (N = 27) completed the MI-based ISL paradigm after receiving continuous theta burst stimulation to the left IPL (TMS), or with the coil angled away from the scalp (sham). Reaction time differences (dRT) and effect sizes between implicit and random sequences assessed success of MI-based learning. Mean dRT for the sham group was 36.1 ± 28.2 ms (d = 0.71). Mean dRT in the TMS group was 7.7 ± 38.5 ms (d = 0.11). These results indicate that inhibition of the left IPL impaired MI-based learning. We conclude that the IPL and likely the visuospatial processes it mediates are critical for MI performance and thus MI-based skill acquisition or learning. Ultimately, these findings have implications for the use of MI in post-stroke rehabilitation.

  6. Overlapping representations for reach depth and direction in caudal superior parietal lobule of macaques.

    PubMed

    Hadjidimitrakis, Kostas; Dal Bo', Giulia; Breveglieri, Rossella; Galletti, Claudio; Fattori, Patrizia

    2015-10-01

    Reaching movements in the real world have typically a direction and a depth component. Despite numerous behavioral studies, there is no consensus on whether reach coordinates are processed in separate or common visuomotor channels. Furthermore, the neural substrates of reach depth in parietal cortex have been ignored in most neurophysiological studies. In the medial posterior parietal area V6A, we recently demonstrated the strong presence of depth signals and the extensive convergence of depth and direction information on single neurons during all phases of a fixate-to-reach task in 3-dimensional (3D) space. Using the same task, in the present work we examined the processing of direction and depth information in area PEc of the caudal superior parietal lobule (SPL) in three Macaca fascicularis monkeys. Across the task, depth and direction had a similar, high incidence of modulatory effect. The effect of direction was stronger than depth during the initial fixation period. As the task progressed toward arm movement execution, depth tuning became more prominent than directional tuning and the number of cells modulated by both depth and direction increased significantly. Neurons tuned by depth showed a small bias for far peripersonal space. Cells with directional modulations were more frequently tuned toward contralateral spatial locations, but ipsilateral space was also represented. These findings, combined with results from neighboring areas V6A and PE, support a rostral-to-caudal gradient of overlapping representations for reach depth and direction in SPL. These findings also support a progressive change from visuospatial (vergence angle) to somatomotor representations of 3D space in SPL.

  7. Early coding of reaching: frontal and parietal association connections of parieto-occipital cortex.

    PubMed

    Caminiti, R; Genovesio, A; Marconi, B; Mayer, A B; Onorati, P; Ferraina, S; Mitsuda, T; Giannetti, S; Squatrito, S; Maioli, M G; Molinari, M

    1999-09-01

    The ipsilateral association connections of the cortex of the dorsal part of the rostral bank of the parieto-occipital sulcus and of the adjoining posterior part of the superior parietal lobule were studied by using different retrograde fluorescent tracers. Fluoro-Ruby, Fast blue and Diamidino yellow were injected into visual area V6A, and dorso-caudal (PMdc, F2) and dorso-rostral (PMdr, F7) premotor cortex, respectively. The parietal area of injection had been previously characterized physiologically in behaving monkeys, through a variety of oculomotor and visuomanual tasks. Area V6A is mainly linked by reciprocal projections to parietal areas 7m, MIP (medial intraparietal) and PEa, and, to a lesser extent, to frontal areas PMdr (rostral dorsal premotor cortex, F7) and PMdc (F2). All these areas project to that part of the dorsocaudal premotor cortex that has a direct access to primary motor cortex. V6A is also connected to area F5 and, to a lesser extent, to 7a, ventral (VIP) and lateral (LIP) intraparietal areas. This pattern of association connections may explain the presence of visually-related and eye-position signals in premotor cortex, as well as the influence of information concerning arm position and movement direction on V6A neural activity. Area V6A emerges as a potential 'early' node of the distributed network underlying visually-guided reaching. In this network, reciprocal association connections probably impose, through re-entrant signalling, a recursive property to the operations leading to the composition of eye and hand motor commands.

  8. Posterior parietal cortex mediates encoding and maintenance processes in change blindness.

    PubMed

    Tseng, Philip; Hsu, Tzu-Yu; Muggleton, Neil G; Tzeng, Ovid J L; Hung, Daisy L; Juan, Chi-Hung

    2010-03-01

    It is commonly accepted that right posterior parietal cortex (PPC) plays an important role in updating spatial representations, directing visuospatial attention, and planning actions. However, recent studies suggest that right PPC may also be involved in processes that are more closely associated with our visual awareness as its activation level positively correlates with successful conscious change detection (Beck, D.M., Rees, G., Frith, C.D., & Lavie, N. (2001). Neural correlates of change detection and change blindness. Nature Neuroscience, 4, 645-650.). Furthermore, disruption of its activity increases the occurrences of change blindness, thus suggesting a causal role for right PPC in change detection (Beck, D.M., Muggleton, N., Walsh, V., & Lavie, N. (2006). Right parietal cortex plays a critical role in change blindness. Cerebral Cortex, 16, 712-717.). In the context of a 1-shot change detection paradigm, we applied transcranial magnetic stimulation (TMS) during different time intervals to elucidate the temporally precise involvement of PPC in change detection. While subjects attempted to detect changes between two image sets separated by a brief time interval, TMS was applied either during the presentation of picture 1 when subjects were encoding and maintaining information into visual short-term memory, or picture 2 when subjects were retrieving information relating to picture 1 and comparing it to picture 2. Our results show that change blindness occurred more often when TMS was applied during the viewing of picture 1, which implies that right PPC plays a crucial role in the processes of encoding and maintaining information in visual short-term memory. In addition, since our stimuli did not involve changes in spatial locations, our findings also support previous studies suggesting that PPC may be involved in the processes of encoding non-spatial visual information (Todd, J.J. & Marois, R. (2004). Capacity limit of visual short-term memory in human

  9. Surgical trauma and CO2-insufflation impact on adhesion formation in parietal and visceral peritoneal lesions.

    PubMed

    Mynbaev, Ospan A; Eliseeva, Marina Yu; Kalzhanov, Zhomart R; Lyutova, Lv; Pismensky, Sergei V; Tinelli, Andrea; Malvasi, Antonio; Kosmas, Ioannis P

    2013-01-01

    CO2-insufflation and electrocoagulation were advanced as causative factors of postsurgical adhesions. We assumed that severe tissue reaction due to electrocoagulation might obscure CO2-insufflation impact on adhesion formation. Therefore, the purpose of this study was to evaluate the effects and interactions of surgical trauma and CO2-insufflation on adhesion formation. Prospective-randomized study with 60 rats, equally divided into 3 groups. In the control group, the sidewall adhesion model was induced by monopolar coagulation of the uterine horn and ipsilateral parietal peritoneum and by mechanical damaging - in the opposite side through open laparoscopy without CO2-insufflation. In two other groups, CO2 was insufflated for 60 min at 15 cm of water, either before or after the sidewall model-induction. Parameters of sidewall and lesion site adhesions of parietal peritoneum and uterine horns were evaluated by scoring system and analyzed by two-way ANOVA with Bonferroni posttests, one-way ANOVA Student-Newman-Keuls multiple comparisons test, as well as by two-tailed unpaired Mann-Whitney test. Monopolar coagulation significantly increased peritoneal lesion site adhesion scores, as compared with the scores for mechanical damaging (p=0.0001). Visceral peritoneal lesion sites were more predisposed to adhesion formation than parietal peritoneal lesion sites (p=0.0009), whereas CO2 did not affect parameters of either sidewall or peritoneal lesion site adhesions, regardless of the insufflation mode (p>0.05). The data suggest that both surgical trauma and peritoneal lesion sites had a substantial impact on adhesion formation, whereas CO2 did not interfere with adhesion parameters irrespective of its insufflation mode. These findings may improve our insights into adhesion formation pathophysiology and open new perspectives in developing future adhesion prevention strategies.

  10. Observational learning of new movement sequences is reflected in fronto-parietal coherence.

    PubMed

    van der Helden, Jurjen; van Schie, Hein T; Rombouts, Christiaan

    2010-12-31

    Mankind is unique in her ability for observational learning, i.e. the transmission of acquired knowledge and behavioral repertoire through observation of others' actions. In the present study we used electrophysiological measures to investigate brain mechanisms of observational learning. Analysis investigated the possible functional coupling between occipital (alpha) and motor (mu) rhythms operating in the 10 Hz frequency range for translating "seeing" into "doing". Subjects observed movement sequences consisting of six consecutive left or right hand button presses directed at one of two target-buttons for subsequent imitation. Each movement sequence was presented four times, intervened by short pause intervals for sequence rehearsal. During a control task subjects observed the same movement sequences without a requirement for subsequent reproduction. Although both alpha and mu rhythms desynchronized during the imitation task relative to the control task, modulations in alpha and mu power were found to be largely independent from each other over time, arguing against a functional coupling of alpha and mu generators during observational learning. This independence was furthermore reflected in the absence of coherence between occipital and motor electrodes overlaying alpha and mu generators. Instead, coherence analysis revealed a pair of symmetric fronto-parietal networks, one over the left and one over the right hemisphere, reflecting stronger coherence during observation of movements than during pauses. Individual differences in fronto-parietal coherence were furthermore found to predict imitation accuracy. The properties of these networks, i.e. their fronto-parietal distribution, their ipsilateral organization and their sensitivity to the observation of movements, match closely with the known properties of the mirror neuron system (MNS) as studied in the macaque brain. These results indicate a functional dissociation between higher order areas for observational

  11. Sequelae of a left-sided parietal stroke: posterior alien hand syndrome.

    PubMed

    Kloesel, Benjamin; Czarnecki, Kathrin; Muir, Jeffery J; Keller, A Scott

    2010-12-01

    Posterior alien hand syndrome is a new addition to a poorly understood group of movement disorders. Historically, anatomical lesions causing uncontrolled limb movement and a feeling of foreignness were found to be located in the corpus callosum or frontal lobe. Recent case reports, however, demonstrate the typical symptoms of alien hand syndrome with lesions located in the parietal/occipital lobes. Disturbance of normal function in these regions tends to produce less complex motor activity, such as hand levitation, along with a sensory component characterized by feeling of estrangement. We discuss a patient who presented with unusual symptoms following an outpatient procedure and was found to have posterior alien hand syndrome. PMID:20824573

  12. Bilateral Carotid-Cavernous Fistulas: An Uncommon Cause of Pituitary Enlargement and Hypopituitarism

    PubMed Central

    Lechan, Ronald M.

    2016-01-01

    Carotid-cavernous fistulas (CCFs) are rare, pathologic communications of the carotid artery and the venous plexus of the cavernous sinus. They can develop spontaneously in certain at risk individuals or following traumatic head injury. Typical clinical manifestations include headache, proptosis, orbital pain, and diplopia. We report a case of bilateral carotid-cavernous fistulas associated with these symptoms and also with pituitary enlargement and hypopituitarism, which improved following surgical intervention. Arterialization of the cavernous sinus and elevated portal pressure may interfere with normal venous drainage and the conveyance of inhibiting and releasing hormones from the hypothalamus, resulting in pituitary enlargement and hypopituitarism. This condition should be considered in the differential diagnosis of hypopituitarism associated with anterior pituitary enlargement. PMID:27651959

  13. Identification of the patient with enlarged prostate: diagnosis and guidelines for management

    PubMed Central

    Kaplan, Steven A

    2007-01-01

    Benign enlargement of the prostate, also referred to as benign prostatic hyperplasia, is a common condition in men. Because enlarged prostate (EP) was viewed historically as a symptomatic condition, management of voiding symptoms with α-blockers was often the goal of therapy. However, it is now recognized that EP is a progressive disorder, which may be complicated by acute urinary retention and which may eventually require EP-related surgery. The 5α-reductase inhibitors decrease dihydrotestosterone levels, which slow disease progression by causing regression of the prostate epithelial cells. These agents are considered disease modifying, and they may reduce the progression of prostate enlargement. This article reviews evaluation, diagnosis, and treatment strategies for EP, and it provides a practical algorithm for management of patients with EP. PMID:17620137

  14. Modeling the Effect of Enlarging Seating Room on Passengers' Preference of Taiwan's Domestic Airlines

    NASA Technical Reports Server (NTRS)

    Lu, Jin-Long; Tsai, Li-Non

    2003-01-01

    This study addresses the need for measuring the effect of enlarging seating room in airplane on passengers' preferences of airline in Taiwan. The results can assist Taiwan's domestic air carriers in better understanding their customers' expectations. Stated choice experiment is used to incorporate passengers' trade-offs in the preferred measurement, and three major attributes are taken into account in the stated choice experiment: (1) type of seat (enlarged or not), (2) price, and (3) brand names of airlines. Furthermore, a binary logit model is used to model the choice behavior of air passengers. The findings show that the type of seat is a major significant variable; price and airline's brand are also significant as well. It concludes that air carriers should put more emphasis on the issue of improving the quality of seat comfort. Keywords: Passengers' preference, Enlarged seating room, Stated choice experiment, Binary logit model.

  15. Nocturnal foraging enhanced by enlarged secondary eyes in a net-casting spider.

    PubMed

    Stafstrom, Jay A; Hebets, Eileen A

    2016-05-01

    Animals that possess extreme sensory structures are predicted to have a related extreme behavioural function. This study focuses on one such extreme sensory structure-the posterior median eyes of the net-casting spider Deinopis spinosa. Although past research has implicated the importance of vision in the nocturnal foraging habits of Deinopis, no direct link between vision in the enlarged eyes and nocturnal foraging has yet been made. To directly test the hypothesis that the enlarged posterior median eyes facilitate visually based nocturnal prey capture, we conducted repeated-measures, visual occlusion trials in both natural and laboratory settings. Our results indicate that D. spinosa relies heavily on visual cues detected by the posterior median eyes to capture cursorial prey items. We suggest that the enlarged posterior median eyes benefit D. spinosa not only through increased diet breadth, but also by allowing spiders to remain active solely at night, thus evading predation by diurnal animals. PMID:27194291

  16. Bilateral Carotid-Cavernous Fistulas: An Uncommon Cause of Pituitary Enlargement and Hypopituitarism.

    PubMed

    Liberatore, Anthony; Lechan, Ronald M

    2016-01-01

    Carotid-cavernous fistulas (CCFs) are rare, pathologic communications of the carotid artery and the venous plexus of the cavernous sinus. They can develop spontaneously in certain at risk individuals or following traumatic head injury. Typical clinical manifestations include headache, proptosis, orbital pain, and diplopia. We report a case of bilateral carotid-cavernous fistulas associated with these symptoms and also with pituitary enlargement and hypopituitarism, which improved following surgical intervention. Arterialization of the cavernous sinus and elevated portal pressure may interfere with normal venous drainage and the conveyance of inhibiting and releasing hormones from the hypothalamus, resulting in pituitary enlargement and hypopituitarism. This condition should be considered in the differential diagnosis of hypopituitarism associated with anterior pituitary enlargement. PMID:27651959

  17. Bilateral Carotid-Cavernous Fistulas: An Uncommon Cause of Pituitary Enlargement and Hypopituitarism

    PubMed Central

    Lechan, Ronald M.

    2016-01-01

    Carotid-cavernous fistulas (CCFs) are rare, pathologic communications of the carotid artery and the venous plexus of the cavernous sinus. They can develop spontaneously in certain at risk individuals or following traumatic head injury. Typical clinical manifestations include headache, proptosis, orbital pain, and diplopia. We report a case of bilateral carotid-cavernous fistulas associated with these symptoms and also with pituitary enlargement and hypopituitarism, which improved following surgical intervention. Arterialization of the cavernous sinus and elevated portal pressure may interfere with normal venous drainage and the conveyance of inhibiting and releasing hormones from the hypothalamus, resulting in pituitary enlargement and hypopituitarism. This condition should be considered in the differential diagnosis of hypopituitarism associated with anterior pituitary enlargement.

  18. Enlarged band gap and electron switch in graphene-based step-barrier structure

    SciTech Connect

    Lu, Wei-Tao Ye, Cheng-Zhi; Li, Wen

    2013-11-04

    We study the transmission through a step-barrier in gapped graphene and propose a method to enlarge the band gap. The step-barrier structure consists of two or more barriers with different strengths. It is found that the band gap could be effectively enlarged and controlled by adjusting the barrier strengths in the light of the mass term. Klein tunneling at oblique incidence is suppressed due to the asymmetry of step-barrier, contrary to the cases in single-barrier and superlattices. Furthermore, a tunable conductance channel could be opened up in the conductance gap, suggesting an application of the structure as an electron switch.

  19. Unusual presentation of localized gingival enlargement associated with a slow-growing odontogenic myxoma

    PubMed Central

    Miranda Rius, Jaume; Nadal, Alfons; Lahor, Eduard; Mtui, Beatus; Brunet, Lluís

    2013-01-01

    Unusual presentation of localized gingival enlargement associated with a subjacent tumoural pathology is reported. The patient was a 55-year-old black male, whose chief complaint was a progressive gingival overgrowth for more than ten years, in the buccal area of the anterior left mandible. According to the clinical features and the radiological diagnosis of odontogenic keratocyst, a conservative surgery with enucleation and curettage was performed. Tissue submitted for histopathological analysis rendered the diagnosis of odontogenic myxoma. After 12-month of follow-up, no evidence of recurrence was found. Clinicians should be cautious when facing any gingival enlargement to avoid diagnostic pitfalls and to indicate the appropriate treatment. PMID:23722914

  20. Fit and fat from enlarged badges: a field experiment on male sand lizards.

    PubMed Central

    Anderholm, Sofia; Olsson, Mats; Wapstra, Erik; Ryberg, Karin

    2004-01-01

    To investigate the impact of nuptial coloration (the badge) on male fitness in the Swedish sand lizard (Lacerta agilis), we conducted a manipulation experiment in a natural population. Males in one group had their badges enlarged by being painted as cheaters and were compared to a control group with respect to mate acquisition, body condition and survival. Badge enlargement did not affect survival, but elevated mate acquisition by almost 400%, and body condition in small males. This increase in condition is likely to stem from greater access to female-associated sites with high food availability. PMID:15252966

  1. Platypnea-orthodeoxia syndrome in patients presenting enlarged aortic root: case report and literature review

    PubMed Central

    Townsend, Raquel da Silva; Costa, Ana Lúcia Martins; Gib, Marcelo Cúrcio; Dexheimer Neto, Felippe Leopoldo

    2014-01-01

    We describe herein a case of a patient who, when in orthostatic positions, had severe hypoxemia and ventilatory dysfunction. Although the severity of symptoms required hospitalization in an intensive care setting, the initial tests only identified the presence of enlarged aortic root, which did not explain the condition. The association of these events with an unusual etiology, namely intracardiac shunt, characterized the diagnosis of platypnea-orthodeoxia syndrome. The literature review shows that, with advancing research methods, there was a progressive increase in the identification of this condition, and this association should be part of the differential diagnosis of dyspnea in patients with enlarged aortic root. PMID:25295827

  2. Diminution and enlargement of the mosquito rhabdom in light and darkness.

    PubMed

    White, R H; Lord, E

    1975-05-01

    The rhabdoms of the larval ocelli of the mosquito Aedes aegypti undergo morphological light and dark adaptation over periods of hours. The rhabdom enlarges during dark adaptation and grows smaller during light adaptation. Diminution is exponential, enlargement linear, and rates of change are proportional to log light intensity. Rhabdoms maintained at a constant intensity level off at a constant volume proportional to log intensity. We argue that changes in rhabdom volume after changes in light intensity reflect an influence of light on the turnover of photoreceptro membrane, and that the volumes at which rhabdoms level off represent equilibria between opposed processes of membrane loss and renewal.

  3. Recency Effects in the Inferior Parietal Lobe during Verbal Recognition Memory.

    PubMed

    Buchsbaum, Bradley R; Ye, Donald; D'Esposito, Mark

    2011-01-01

    The most recently encountered information is often most easily remembered in psychological tests of memory. Recent investigations of the neural basis of such "recency effects" have shown that activation in the lateral inferior parietal cortex (LIPC) tracks the recency of a probe item when subjects make recognition memory judgments. A key question regarding recency effects in the LIPC is whether they fundamentally reflect the storage (and strength) of information in memory, or whether such effects are a consequence of task difficulty or an upswing in resting state network activity. Using functional magnetic resonance imaging we show that recency effects in the LIPC are independent of the difficulty of recognition memory decisions, that they are not a by-product of an increase in resting state network activity, and that they appear to dissociate from regions known to be involved in verbal working memory maintenance. We conclude with a discussion of two alternative explanations - the memory strength and "expectancy" hypotheses, respectively - of the parietal lobe recency effect.

  4. Parietal endoderm secreted S100A4 promotes early cardiomyogenesis in embryoid bodies

    SciTech Connect

    Stary, Martina; Schneider, Mikael; Sheikh, Soren P.; Weitzer, Georg . E-mail: georg.weitzer@meduniwien.ac.at

    2006-05-05

    Cardiomyogenesis is influenced by factors secreted by anterior-lateral and extra-embryonic endoderm. Differentiation of embryonic stem cells in embryoid bodies allows to study the influence of growth factors on cardiomyogenesis. By these means SPARC was identified as a new factor enhancing cardiomyogenesis [M. Stary, W. Pasteiner, A. Summer, A. Hrdina, A. Eger, G. Weitzer, Parietal endoderm secreted SPARC promotes early cardiomyogenesis in vitro, Exp. Cell Res. 310 (2005) 331-341]. Here we report a similar and new function for S100A4, a calcium-binding protein of the EF-hand type. S100A4 is secreted by parietal endoderm and promotes early differentiation and proliferation of cardiomyocytes. Oligomeric S100A4 supports cardiomyogenesis in a concentration-dependent manner, whereas inhibition of autocrine S100A4 severely attenuates cardiomyogenesis. S100A4 specifically influences transcription in differentiating cardiomyocytes, as evident from increased expression of cardiac transcription factor genes nkx2.5 and mef2C. These data suggest that S100A4, like SPARC, plays a supportive role in early in vitro cardiomyogenesis.

  5. Neural circuitry involved in quitting after repeated failures: role of the cingulate and temporal parietal junction

    PubMed Central

    Zhao, Weihua; Kendrick, Keith M; Chen, Fei; Li, Hong; Feng, Tingyong

    2016-01-01

    The more times people fail the more likely they are to give up, however little is known about the neural mechanisms underlying this impact of repeated failure on decision making. Here we have used a visual shape discrimination task with computer-controlled feedback combined with functional magnetic resonance imaging (fMRI) to investigate the neural circuits involved. The behavioral task confirmed that the more times subjects experienced failure the more likely they were to give up, with three successive failures being the key threshold and the majority of subjects reaching the point where they decided to quit and try a new stimulus set after three or four failures. The fMRI analysis revealed activity changes in frontal, parietal, temporal, limbic and striatal regions, especially anterior cingulate cortex (ACC), posterior cingulate cortex (PCC) and temporal parietal junction (TPJ) associated with the number of previous failures experienced. Furthermore, their parameter estimates were predictive of subjects’ quitting rate. Thus, subjects reach the point where they decide to quit after three/four failures and this is associated with differential changes in brain regions involved in error monitoring and reward which regulate both failure detection and changes in decision-making strategy. PMID:27097529

  6. [A case of conduction aphasia due to small infarction in the left parietal lobe].

    PubMed

    Ibayashi, Katsuhiko

    2002-08-01

    This is a report on the patient with conduction aphAsia due to small infarction in the left parietal lobe. The patient is a right-handed man aged 74, who developed a speech disorder and mild paralysis of the right hand on November 13. 1996. A CT scan showed a small low-density in the supramarginal gyrus of the left parietal lobe. Standard Language Test of aphasia (SLTA) conducted at five days after admission to the hospital showed preserved auditory comprehension and phonemic para-aphasia symptoms with respect to volitional speech, naming, reading aloud and repetition. Frequent self-correction was also observed while repetition was not remarkably impaired. A test at three months after the onset revealed generally fluent speech, while there still remained occasional phonemic para-aphasia and self-correction for the speech disruption. Three years and four months later, most of the aphasic syndromes disappeared, although the patient claimed he still had difficulty in speaking. This case suggests that conduction aphasia can be caused by a lesion, though small, located in arcuate fibers of the cerebrum. The characteristics are phonemic para-aphasia with respect to general speech functions as well as self-correction toward target words. The indicated that lesions in the pathway connecting Broca's area and Wernicke's area causes difficulties in selecting accurate phonemes due to a malfunctioning interface between the two areas. PMID:12701218

  7. Frontal and occipital-parietal alpha oscillations distinguish between stimulus conflict and response conflict

    PubMed Central

    Tang, Dandan; Hu, Li; Lei, Yi; Li, Hong; Chen, Antao

    2015-01-01

    Conflicts between target and distraction can occur at the level of both stimulus and response processing. However, the neural oscillations underlying occurrence of the interference in different levels have not been understood well. Here, we reveal such a neural oscillation modulation by combining a 4:2 mapping design (two targets are mapped into one response key) with a practice paradigm (pretest, practice, and posttest) when healthy human participants were performing a novel color-word flanker task. Response time (RT) results revealed constant stimulus conflict (SC, stimulus incongruent minus congruent, SI-CO) but increased response conflict (RC, response incongruent minus stimulus incongruent, RI-SI) with practice. Event-related potential (ERP) results demonstrated stable P3 amplitude differences for the SI-CO in the centro-parietal region across practice, which may reflect maintenance of the stimulus processing; and significantly larger P3 amplitudes in the same region for the RI relative to SI trial type in posttest, which may reflect inhibition of the distraction response. Further, neural oscillatory results showed that with practice, the lower alpha band in the frontal region and the upper alpha band in the occipital-parietal region distinguished between stimulus- and response-conflicts, respectively, suggesting that practice reduces the alertness (sensitiveness) of the brain to conflict occurrence, and enhances stimulus-response associations. PMID:26300758

  8. Formation of concentric saccules in murine parietal cells after injection of diazo-oxo-norleucine.

    PubMed

    Michaels, J E

    1979-04-01

    After treatment with various chemical and physical agents, flattened or ring-like saccules may occur in the cytoplasm of parietal cells of the gastric glands of several species of mammals. In the current investigation, similar structures appeared after treatment with high dosages of diazo-oxo-norleucine (DON), a glutamine antagonist. A tentative sequence for their formation is suggested. Saccules formed of unit membrane became abundant in some parietal cells of the treated mice. Single saccules often had narrow lumens and peripheral distensions. The saccules, either singular or several stacked together, became progressively more curved, enclosing a region of cytoplasm that often contained glycogen-like particles and occasionally vesicles or other organelles. Many of the concentric saccules were close to an intracellular canaliculus. Membrane bound cytoplasm containing glycogen-like particles occasionally occurred in the canaliculi, suggesting that exocytosis had occurred. Cytochemistry revealed that glycoproteins were associated with the concentric saccules, probably located on the luminal surface. The glycogen-like particles in all locations stained in a manner characteristic of glycogen. It is suggested that the concentric saccules may form from vesicles of the tubulovesicular system.

  9. Common substrate for mental arithmetic and finger representation in the parietal cortex.

    PubMed

    Andres, Michael; Michaux, Nicolas; Pesenti, Mauro

    2012-09-01

    The history of mathematics provides several examples of the use of fingers to count or calculate. These observations converge with developmental data showing that fingers play a critical role in the acquisition of arithmetic knowledge. Further studies evidenced specific interference of finger movements with arithmetic problem solving in adults, raising the question of whether or not finger and number manipulations rely on common brain areas. In the present study, functional magnetic resonance imaging (fMRI) was used to investigate the possible overlap between the brain areas involved in mental arithmetic and those involved in finger discrimination. Solving subtraction and multiplication problems was found to increase cerebral activation bilaterally in the horizontal part of the intraparietal sulcus (hIPS) and in the posterior part of the superior parietal lobule (PSPL). Finger discrimination was associated with increased activity in a bilateral occipito-parieto-precentral network extending from the extrastriate body area to the primary somatosensory and motor cortices. A conjunction analysis showed common areas for mental arithmetic and finger representation in the hIPS and PSPL bilaterally. Voxelwise correlations further showed that finger discrimination and mental arithmetic induced a similar pattern of activity within the parietal areas only. Pattern similarity was more important for the left than for the right hIPS and for subtraction than for multiplication. These findings provide the first evidence that the brain circuits involved in finger representation also underlie arithmetic operations in adults. PMID:22634854

  10. Functional heterogeneity in posterior parietal cortex across attention and episodic memory retrieval.

    PubMed

    Hutchinson, J Benjamin; Uncapher, Melina R; Weiner, Kevin S; Bressler, David W; Silver, Michael A; Preston, Alison R; Wagner, Anthony D

    2014-01-01

    While attention is critical for event memory, debate has arisen regarding the extent to which posterior parietal cortex (PPC) activation during episodic retrieval reflects engagement of PPC-mediated mechanisms of attention. Here, we directly examined the relationship between attention and memory, within and across subjects, using functional magnetic resonance imaging attention-mapping and episodic retrieval paradigms. During retrieval, 4 functionally dissociable PPC regions were identified. Specifically, 2 PPC regions positively tracked retrieval outcomes: lateral intraparietal sulcus (latIPS) indexed graded item memory strength, whereas angular gyrus (AnG) tracked recollection. By contrast, 2 other PPC regions demonstrated nonmonotonic relationships with retrieval: superior parietal lobule (SPL) tracked retrieval reaction time, consistent with a graded engagement of top-down attention, whereas temporoparietal junction displayed a complex pattern of below-baseline retrieval activity, perhaps reflecting disengagement of bottom-up attention. Analyses of retrieval effects in PPC topographic spatial attention maps (IPS0-IPS5; SPL1) revealed that IPS5 and SPL1 exhibited a nonmonotonic relationship with retrieval outcomes resembling that in the SPL region, further suggesting that SPL activation during retrieval reflects top-down attention. While demands on PPC attention mechanisms vary during retrieval attempts, the present functional parcellation of PPC indicates that 2 additional mechanisms (mediated by latIPS and AnG) positively track retrieval outcomes.

  11. Further observations on the fine structure of the parietal eye of lizards.

    PubMed

    EAKIN, R M; WESTFALL, J A

    1960-10-01

    An electron microscopical study of the third eye of the Western Fence Lizard, Sceloporus occidentalis, fixed with 1 per cent osmium tetroxide, pH 7.4-7.6, for 16 to 20 hours at 0 degrees C., revealed the following new facts. The fibrillar system of the retinal photoreceptor consists of nine double fibrils enclosed in a sheath. Pigment cells and lens cells possess similar systems. Two short cylindrical centrioles are associated with the fibrillar apparatus: one, from which striated rootlets extend inward, lies at the base of the fibrils, with the other at an oblique angle to the axis of the system. A Golgi complex, whorls of endoplasmic reticulum, lipid (?) droplets, and other organelles and inclusions in the photoreceptors are described. An axon leads from the base of the photoreceptor into the nervous layer of the retina which consists of many nerve fibers and large ganglion cells. Although the pattern of neural connections has not yet been determined, some synapses were found. The parietal nerve consists of about 250 non-medullated fibers. The capsule of the eye usually has a layer of iridocytes, which contain rows of guanine (?) rods. A few parietal eyes of the Granite Night Lizard, Xantusia henshawi, were also examined. Large lipid (?) droplets occur in the bases of their receptoral processes.

  12. Spatial effects of shifting prisms on properties of posterior parietal cortex neurons

    PubMed Central

    Karkhanis, Anushree N; Heider, Barbara; Silva, Fabian Muñoz; Siegel, Ralph M

    2014-01-01

    The posterior parietal cortex contains neurons that respond to visual stimulation and motor behaviour. The objective of the current study was to test short-term adaptation in neurons in macaque area 7a and the dorsal prelunate during visually guided reaching using Fresnel prisms that displaced the visual field. The visual perturbation shifted the eye position and created a mismatch between perceived and actual reach location. Two non-human primates were trained to reach to visual targets before, during and after prism exposure while fixating the reach target in different locations. They were required to reach to the physical location of the reach target and not the perceived, displaced location. While behavioural adaptation to the prisms occurred within a few trials, the majority of neurons responded to the distortion either with substantial changes in spatial eye position tuning or changes in overall firing rate. These changes persisted even after prism removal. The spatial changes were not correlated with the direction of induced prism shift. The transformation of gain fields between conditions was estimated by calculating the translation and rotation in Euler angles. Rotations and translations of the horizontal and vertical spatial components occurred in a systematic manner for the population of neurons suggesting that the posterior parietal cortex retains a constant representation of the visual field remapping between experimental conditions. PMID:24928956

  13. Intentional signals during saccadic and reaching delays in the human posterior parietal cortex.

    PubMed

    Galati, Gaspare; Committeri, Giorgia; Pitzalis, Sabrina; Pelle, Gina; Patria, Fabiana; Fattori, Patrizia; Galletti, Claudio

    2011-12-01

    In the monkey posterior parietal cortex (PPC), there is clear evidence of anatomically segregated neuronal populations specialized for planning saccades and arm-reaching movements. However, functional neuroimaging studies in humans have yielded controversial results. Here we show that the human PPC contains distinct subregions responsive to salient visual cues, some of which combine spatial and action-related signals into 'intentional' signals. Participants underwent event-related functional magnetic resonance imaging while performing delayed saccades and long-range arm reaches instructed by visual cues. We focused on activity in the time period following the cue and preceding the actual movement. The use of individual cortical surface reconstructions with detailed sulcal labeling allowed the definition of six responsive regions with distinctive anatomical locations in the PPC. Each region exhibited a distinctive combination of transient and sustained signals during the delay, modulated by either the cue spatial location (contralateral vs. ipsilateral), the instructed action (saccades vs. reaching) or both. Importantly, a lateral and a medial dorsal parietal region showed sustained responses during the delay preferentially for contralateral saccadic and reaching trials, respectively. In the lateral region, preference for saccades was evident only as a more sustained response during saccadic vs. reaching delays, whereas the medial region also showed a higher transient response to cues signaling reaching vs. saccadic actions. These response profiles closely match the behavior of neurons in the macaque lateral and medial intraparietal area, respectively, and suggest that these corresponding human regions are encoding spatially directed action plans or 'intentions'.

  14. Multimodal integration for the representation of space in the posterior parietal cortex.

    PubMed Central

    Andersen, R A

    1997-01-01

    The posterior parietal cortex has long been considered an 'association' area that combines information from different sensory modalities to form a cognitive representation of space. However, until recently little has been known about the neural mechanisms responsible for this important cognitive process. Recent experiments from the author's laboratory indicate that visual, somatosensory, auditory and vestibular signals are combined in areas LIP and 7a of the posterior parietal cortex. The integration of these signals can represent the locations of stimuli with respect to the observer and within the environment. Area MSTd combines visual motion signals, similar to those generated during an observer's movement through the environment, with eye-movement and vestibular signals. This integration appears to play a role in specifying the path on which the observer is moving. All three cortical areas combine different modalities into common spatial frames by using a gain-field mechanism. The spatial representations in areas LIP and 7a appear to be important for specifying the locations of targets for actions such as eye movements or reaching; the spatial representation within area MSTd appears to be important for navigation and the perceptual stability of motion signals. PMID:9368930

  15. True Memory, False Memory, and Subjective Recollection Deficits after Focal Parietal Lobe Lesions

    PubMed Central

    Drowos, David B.; Berryhill, Marian; André, Jessica M.; Olson, Ingrid R.

    2010-01-01

    Objective There is mounting evidence that the posterior parietal cortex (PPC) plays an important role in episodic memory. We previously found that patients with PPC damage exhibit retrieval-related episodic memory deficits. Our objective was to assess whether parietal lobe damage affects episodic memory on a different task: the Deese-Roediger-McDermott (DRM) false-memory paradigm. Method Two patients with bilateral PPC damage and matched controls were tested. In Experiment 1, the task was to remember words; in Experiment 2 the task was to remember pictures of common objects. Prior studies have shown that normal participants have high levels of false memory to words, low levels to pictures. Results The patients exhibited significantly lower levels of false memory to words. The patients' false memories were accompanied by reduced levels of recollection, as tested by a Remember/Know procedure. It is unlikely that a failure of gist processing accounts for these results, as patients accurately remembered thematic elements of short vignettes, but failed to remember details. These results support the view that portions of the PPC play a critical role in objective and subjective aspects of recollection. PMID:20604621

  16. Anodal tDCS targeting the left temporo-parietal junction disrupts verbal reality-monitoring.

    PubMed

    Mondino, Marine; Poulet, Emmanuel; Suaud-Chagny, Marie-Françoise; Brunelin, Jerome

    2016-08-01

    Using transcranial direct current stimulation (tDCS) we aimed to investigate the causal role of the left temporo-parietal and prefrontal regions in source-monitoring. Forty-two healthy participants received tDCS while performing a verbal reality-monitoring task (requiring discrimination between imagined and heard words) and a verbal internal source-monitoring task (requiring discrimination between imagined and said words). In 2 randomized crossover studies, 21 participants received active and sham anodal tDCS applied over the left temporo-parietal junction (TPJ) and 21 participants received active and sham cathodal tDCS applied over the left prefrontal cortex (PFC). The reference electrode was placed over the right occipital region in both experiments. Active tDCS over the left TPJ decreased reality-monitoring performance but did not modulate internal source-monitoring performance. Participants were more likely to misattribute self-generated events to externally perceived events (externalization bias). Active tDCS over the left PFC did not modulate performance of participants in both tasks. In summary, anodal tDCS applied over the left TPJ, assumed to enhance cortical excitability, can alter reality-monitoring processes in healthy subjects. Such abnormal reality-monitoring performances have been reported in hallucinating patients with schizophrenia known to display hyperactivity of the left TPJ. Our results highlighted the role of the left TPJ in self/other recognition.

  17. Abnormalities in personal space and parietal-frontal function in schizophrenia.

    PubMed

    Holt, Daphne J; Boeke, Emily A; Coombs, Garth; DeCross, Stephanie N; Cassidy, Brittany S; Stufflebeam, Steven; Rauch, Scott L; Tootell, Roger B H

    2015-01-01

    Schizophrenia is associated with subtle abnormalities in day-to-day social behaviors, including a tendency in some patients to "keep their distance" from others in physical space. The neural basis of this abnormality, and related changes in social functioning, is unknown. Here we examined, in schizophrenic patients and healthy control subjects, the functioning of a parietal-frontal network involved in monitoring the space immediately surrounding the body ("personal space"). Using fMRI, we found that one region of this network, the dorsal intraparietal sulcus (DIPS), was hyper-responsive in schizophrenic patients to face stimuli appearing to move towards the subjects, intruding into personal space. This hyper-responsivity was predicted both by the size of personal space (which was abnormally elevated in the schizophrenia group) and the severity of negative symptoms. In contrast, in a second study, the activity of two lower-level visual areas that send information to DIPS (the fusiform face area and middle temporal area) was normal in schizophrenia. Together, these findings suggest that changes in parietal-frontal networks that support the sensory-guided initiation of behavior, including actions occurring in the space surrounding the body, contribute to social dysfunction and negative symptoms in schizophrenia. PMID:26484048

  18. Alpha stimulation of the human parietal cortex attunes tactile perception to external space.

    PubMed

    Ruzzoli, Manuela; Soto-Faraco, Salvador

    2014-02-01

    An intriguing question in neuroscience concerns how somatosensory events on the skin are represented in the human brain. Since Head and Holmes' [1] neuropsychological dissociation between localizing touch on the skin and localizing body parts in external space, touch is considered to operate in a variety of spatial reference frames [2]. At least two representations of space are in competition during orienting to touch: a somatotopic one, reflecting the organization of the somatosensory cortex (S1) [3], and a more abstract, external reference frame that factors postural changes in relation to body parts and/or external space [4, 5]. Previous transcranial magnetic stimulation (TMS) studies suggest that the posterior parietal cortex (PPC) plays a key role in supporting representations as well as orienting attention in an external reference frame [4, 6]. Here, we capitalized on the TMS entrainment approach [7, 8], targeting the intraparietal sulcus (IPS). We found that frequency-specific (10 Hz) tuning of the PPC induced spatially specific enhancement of tactile detection that was expressed in an external reference frame. This finding establishes a tight causal link between a concrete form of brain activity (10 Hz oscillation) and a specific type of spatial representation, revealing a fundamental property of how the parietal cortex encodes information. PMID:24440394

  19. Contextual modulation of pain in masochists: involvement of the parietal operculum and insula.

    PubMed

    Kamping, Sandra; Andoh, Jamila; Bomba, Isabelle C; Diers, Martin; Diesch, Eugen; Flor, Herta

    2016-02-01

    Pain can be modulated by contextual stimuli, such as emotions, social factors, or specific bodily perceptions. We presented painful laser stimuli together with body-related masochistic visual stimuli to persons with and without preferred masochistic sexual behavior and used neutral, positive, and negative pictures with and without painful stimuli as control. Masochists reported substantially reduced pain intensity and unpleasantness in the masochistic context compared with controls but had unaltered pain perception in the other conditions. Functional magnetic resonance imaging revealed that masochists activated brain areas involved in sensory-discriminative processing rather than affective pain processing when they received painful stimuli on a masochistic background. The masochists compared with the controls displayed attenuated functional connectivity of the parietal operculum with the left and right insulae, the central operculum, and the supramarginal gyrus. Masochists additionally showed negative correlations between the duration of interest in masochistic activities and activation of areas involved in motor activity and affective processing. We propose that the parietal operculum serves as an important relay station that attenuates the affective-motivational aspects of pain in masochists. This novel mechanism of pain modulation might be related to multisensory integration and has important implications for the assessment and treatment of pain. PMID:26808014

  20. Further observations on the fine structure of the parietal eye of lizards.

    PubMed

    EAKIN, R M; WESTFALL, J A

    1960-10-01

    An electron microscopical study of the third eye of the Western Fence Lizard, Sceloporus occidentalis, fixed with 1 per cent osmium tetroxide, pH 7.4-7.6, for 16 to 20 hours at 0 degrees C., revealed the following new facts. The fibrillar system of the retinal photoreceptor consists of nine double fibrils enclosed in a sheath. Pigment cells and lens cells possess similar systems. Two short cylindrical centrioles are associated with the fibrillar apparatus: one, from which striated rootlets extend inward, lies at the base of the fibrils, with the other at an oblique angle to the axis of the system. A Golgi complex, whorls of endoplasmic reticulum, lipid (?) droplets, and other organelles and inclusions in the photoreceptors are described. An axon leads from the base of the photoreceptor into the nervous layer of the retina which consists of many nerve fibers and large ganglion cells. Although the pattern of neural connections has not yet been determined, some synapses were found. The parietal nerve consists of about 250 non-medullated fibers. The capsule of the eye usually has a layer of iridocytes, which contain rows of guanine (?) rods. A few parietal eyes of the Granite Night Lizard, Xantusia henshawi, were also examined. Large lipid (?) droplets occur in the bases of their receptoral processes. PMID:13725484

  1. Parietal and Frontal Cortex Encode Stimulus-Specific Mnemonic Representations during Visual Working Memory.

    PubMed

    Ester, Edward F; Sprague, Thomas C; Serences, John T

    2015-08-19

    Working memory (WM) enables the storage and manipulation of information in an active state. WM storage has long been associated with sustained increases in activation across a network of frontal and parietal cortical regions. However, recent evidence suggests that these regions primarily encode information related to general task goals rather than feature-selective representations of specific memoranda. These goal-related representations are thought to provide top-down feedback that coordinates the representation of fine-grained details in early sensory areas. Here, we test this model using fMRI-based reconstructions of remembered visual details from region-level activation patterns. We could reconstruct high-fidelity representations of a remembered orientation based on activation patterns in occipital visual cortex and in several sub-regions of frontal and parietal cortex, independent of sustained increases in mean activation. These results challenge models of WM that postulate disjoint frontoparietal "top-down control" and posterior sensory "feature storage" networks. PMID:26257053

  2. Parietal Fast Sleep Spindle Density Decrease in Alzheimer's Disease and Amnesic Mild Cognitive Impairment

    PubMed Central

    Gorgoni, Maurizio; Lauri, Giulia; Truglia, Ilaria; Cordone, Susanna; Sarasso, Simone; Scarpelli, Serena; Mangiaruga, Anastasia; D'Atri, Aurora; Tempesta, Daniela; Ferrara, Michele; Marra, Camillo; Rossini, Paolo Maria; De Gennaro, Luigi

    2016-01-01

    Several studies have identified two types of sleep spindles: fast (13–15 Hz) centroparietal and slow (11–13 Hz) frontal spindles. Alterations in spindle activity have been observed in Alzheimer's disease (AD) and Mild Cognitive Impairment (MCI). Only few studies have separately assessed fast and slow spindles in these patients showing a reduction of fast spindle count, but the possible local specificity of this phenomenon and its relation to cognitive decline severity are not clear. Moreover, fast and slow spindle density have never been assessed in AD/MCI. We have assessed fast and slow spindles in 15 AD patients, 15 amnesic MCI patients, and 15 healthy elderly controls (HC). Participants underwent baseline polysomnographic recording (19 cortical derivations). Spindles during nonrapid eye movements sleep were automatically detected, and spindle densities of the three groups were compared in the derivations where fast and slow spindles exhibited their maximum expression (parietal and frontal, resp.). AD and MCI patients showed a significant parietal fast spindle density decrease, positively correlated with Minimental State Examination scores. Our results suggest that AD-related changes in spindle density are specific for frequency and location, are related to cognitive decline severity, and may have an early onset in the pathology development. PMID:27066274

  3. Contextual modulation of pain in masochists: involvement of the parietal operculum and insula.

    PubMed

    Kamping, Sandra; Andoh, Jamila; Bomba, Isabelle C; Diers, Martin; Diesch, Eugen; Flor, Herta

    2016-02-01

    Pain can be modulated by contextual stimuli, such as emotions, social factors, or specific bodily perceptions. We presented painful laser stimuli together with body-related masochistic visual stimuli to persons with and without preferred masochistic sexual behavior and used neutral, positive, and negative pictures with and without painful stimuli as control. Masochists reported substantially reduced pain intensity and unpleasantness in the masochistic context compared with controls but had unaltered pain perception in the other conditions. Functional magnetic resonance imaging revealed that masochists activated brain areas involved in sensory-discriminative processing rather than affective pain processing when they received painful stimuli on a masochistic background. The masochists compared with the controls displayed attenuated functional connectivity of the parietal operculum with the left and right insulae, the central operculum, and the supramarginal gyrus. Masochists additionally showed negative correlations between the duration of interest in masochistic activities and activation of areas involved in motor activity and affective processing. We propose that the parietal operculum serves as an important relay station that attenuates the affective-motivational aspects of pain in masochists. This novel mechanism of pain modulation might be related to multisensory integration and has important implications for the assessment and treatment of pain.

  4. Abnormalities in personal space and parietal-frontal function in schizophrenia.

    PubMed

    Holt, Daphne J; Boeke, Emily A; Coombs, Garth; DeCross, Stephanie N; Cassidy, Brittany S; Stufflebeam, Steven; Rauch, Scott L; Tootell, Roger B H

    2015-01-01

    Schizophrenia is associated with subtle abnormalities in day-to-day social behaviors, including a tendency in some patients to "keep their distance" from others in physical space. The neural basis of this abnormality, and related changes in social functioning, is unknown. Here we examined, in schizophrenic patients and healthy control subjects, the functioning of a parietal-frontal network involved in monitoring the space immediately surrounding the body ("personal space"). Using fMRI, we found that one region of this network, the dorsal intraparietal sulcus (DIPS), was hyper-responsive in schizophrenic patients to face stimuli appearing to move towards the subjects, intruding into personal space. This hyper-responsivity was predicted both by the size of personal space (which was abnormally elevated in the schizophrenia group) and the severity of negative symptoms. In contrast, in a second study, the activity of two lower-level visual areas that send information to DIPS (the fusiform face area and middle temporal area) was normal in schizophrenia. Together, these findings suggest that changes in parietal-frontal networks that support the sensory-guided initiation of behavior, including actions occurring in the space surrounding the body, contribute to social dysfunction and negative symptoms in schizophrenia.

  5. ERP adaptation provides direct evidence for early mirror neuron activation in the inferior parietal lobule.

    PubMed

    Möhring, Nicole; Brandt, Emily S L; Mohr, Bettina; Pulvermüller, Friedemann; Neuhaus, Andres H

    2014-10-01

    Mirror neuron systems are frequently investigated by assessing overlapping brain activity during observation and execution of actions; however, distinct neuronal subpopulations may be activated that fall below the spatial resolution of magnetic resonance techniques. This shortfall can be resolved using repetition suppression paradigms that identify physiological adaptation processes caused by repeated activation of identical neuronal circuits. Here, event-related potentials were used to investigate the time course of mirror neuron circuit activation using repetition suppression within and across action observation and action execution modalities. In a lip-reading and speech production paradigm, the N170 component indexed stimulus repetition by adapting to both cross-modal and intra-modal repetitions in the left hemisphere. Neuronal source localization revealed activation of the left inferior parietal lobule during cross-modal relative to intra-modal trials. These results provide support for the position that the same neuronal circuits are activated in perceiving and performing articulatory actions. Moreover, our data strongly suggest that inferior parietal lobule mirror neurons are activated relatively early in time, which indicates partly automatic processes of linguistic perception and mirroring. Repetition suppression paradigms therefore help to elucidate neuronal correlates of different cognitive processes and may serve as a starting point for advanced electrophysiological research on mirror neurons.

  6. fMRI adaptation reveals mirror neurons in human inferior parietal cortex.

    PubMed

    Chong, Trevor T-J; Cunnington, Ross; Williams, Mark A; Kanwisher, Nancy; Mattingley, Jason B

    2008-10-28

    Mirror neurons, as originally described in the macaque, have two defining properties [1, 2]: They respond specifically to a particular action (e.g., bringing an object to the mouth), and they produce their action-specific responses independent of whether the monkey executes the action or passively observes a conspecific performing the same action. In humans, action observation and action execution engage a network of frontal, parietal, and temporal areas. However, it is unclear whether these responses reflect the activity of a single population that represents both observed and executed actions in a common neural code or the activity of distinct but overlapping populations of exclusively perceptual and motor neurons [3]. Here, we used fMRI adaptation to show that the right inferior parietal lobe (IPL) responds independently to specific actions regardless of whether they are observed or executed. Specifically, responses in the right IPL were attenuated when participants observed a recently executed action relative to one that had not previously been performed. This adaptation across action and perception demonstrates that the right IPL responds selectively to the motoric and perceptual representations of actions and is the first evidence for a neural response in humans that shows both defining properties of mirror neurons.

  7. Lateral posterior parietal activity during reality monitoring discriminations of memories of high and low perceptual vividness.

    PubMed

    King, Danielle R; Schubert, Misty L; Miller, Michael B

    2015-09-01

    Regions of the lateral posterior parietal cortex (PPC) tend to be more active during recognition of previously studied items compared to correct rejection of unstudied items. Previously, we demonstrated that this effect is source-specific. While items that were encoded through visual perception elicited robust successful retrieval activity in the lateral PPC during a subsequent source memory test, items that were visually imagined did not elicit this effect. Memories of perceived events typically contain more perceptually-based contextual details than memories of imagined events. Therefore, source-based differences in lateral parietal activity might be due to a difference in the perceptual vividness of memories of perceived and imagined events. The goal of the present study was to test this hypothesis. Participants perceived and imagined items in both high and low perceptual vividness conditions. Experiment 1 demonstrated that memories for items encoded in the high vividness conditions contained significantly greater visual detail than memories encoded in the low vividness conditions. In Experiment 2, participants were scanned while they made source memory judgments about items that were previously perceived and imagined in high and low vividness conditions. Consistent with previous findings, the left lateral PPC was more active during retrieval of perceived compared to imagined events. However, lateral PPC activity did not vary according to vividness, suggesting that source effects in this region cannot be explained by a difference in the perceptual vividness of memories encoded through perception versus imagination.

  8. Neuromodulation of parietal and motor activity affects motor planning and execution.

    PubMed

    Convento, Silvia; Bolognini, Nadia; Fusaro, Martina; Lollo, Federica; Vallar, Giuseppe

    2014-08-01

    Transcranial direct current stimulation (tDCS) is a non-invasive tool, which effectively modulates behavior, and related brain activity. When applied to the primary motor cortex (M1), tDCS affects motor function, enhancing or decreasing performance of both healthy participants and brain-damaged patients. Beyond M1, the posterior parietal cortex (PPC) is also crucially involved in controlling and guiding movement. Therefore, we explored whether the modulation of cortical excitability within PPC can also affect hand motor function in healthy right-handed participants. In Experiment 1, anodal tDCS (2 mA, 10 min) was applied to PPC and to M1 of both hemispheres. Skilled motor function of the non-dominant left hand, measured using the Jebsen-Taylor Hand Function Test (JTT), improved after anodal tDCS of the right, contralateral M1, as well as after the anodal stimulation of the left, ipsilateral PPC. Conversely, in Experiment 2, cathodal tDCS of the left PPC, or of the right M1, reduced motor performance of the left hand. Finally, Experiment 3 shows that the anodal tDCS of the left PPC selectively facilitated action planning, while the anodal tDCS of the right M1 modulated action execution only. This evidence shows that motor improvement induced by left parietal and right motor stimulations relies on substantial different mechanisms, opening up novel perspectives in the neurorehabilitation of stroke patients with motor and apraxic disorders.

  9. ERP adaptation provides direct evidence for early mirror neuron activation in the inferior parietal lobule.

    PubMed

    Möhring, Nicole; Brandt, Emily S L; Mohr, Bettina; Pulvermüller, Friedemann; Neuhaus, Andres H

    2014-10-01

    Mirror neuron systems are frequently investigated by assessing overlapping brain activity during observation and execution of actions; however, distinct neuronal subpopulations may be activated that fall below the spatial resolution of magnetic resonance techniques. This shortfall can be resolved using repetition suppression paradigms that identify physiological adaptation processes caused by repeated activation of identical neuronal circuits. Here, event-related potentials were used to investigate the time course of mirror neuron circuit activation using repetition suppression within and across action observation and action execution modalities. In a lip-reading and speech production paradigm, the N170 component indexed stimulus repetition by adapting to both cross-modal and intra-modal repetitions in the left hemisphere. Neuronal source localization revealed activation of the left inferior parietal lobule during cross-modal relative to intra-modal trials. These results provide support for the position that the same neuronal circuits are activated in perceiving and performing articulatory actions. Moreover, our data strongly suggest that inferior parietal lobule mirror neurons are activated relatively early in time, which indicates partly automatic processes of linguistic perception and mirroring. Repetition suppression paradigms therefore help to elucidate neuronal correlates of different cognitive processes and may serve as a starting point for advanced electrophysiological research on mirror neurons. PMID:25017963

  10. Examination of Frontal and Parietal Tectocortical Attention Pathways in Spina Bifida Meningomyelocele Using Probabilistic Diffusion Tractography

    PubMed Central

    Juranek, Jenifer; Stuebing, Karla; Cirino, Paul T.; Dennis, Maureen; Fletcher, Jack M.

    2013-01-01

    Abstract Abnormalities of the midbrain tectum are common but variable malformations in spina bifida meningomyelocele (SBM) and have been linked to neuropsychological deficits in attention orienting. The degree to which variations in tectum structure influence white matter (WM) connectivity to cortical regions is unknown. To assess the relationship of tectal structure and connectivity to frontal and parietal cortical regions, probabilistic diffusion tractography was performed on 106 individuals (80 SBM, 26 typically developing [TD]) to isolate anterior versus posterior tectocortical WM pathways. Results showed that those with SBM exhibited significantly reduced tectal volume, along with decreased fractional anisotropy (FA) in posterior but not anterior tectocortical WM pathways when compared with TD individuals. The group with SBM also showed greater within-subject discrepancies between frontal and parietal WM integrity compared with the TD group. Of those with SBM, qualitative classification of tectal beaking based on radiological review was associated with increased axial diffusivity across both anterior and posterior tectocortical pathways, relative to individuals with SBM and a normal appearing tectum. These results support previous volumetric findings of greater impairment to posterior versus anterior brain regions in SBM, and quantifiably relate tectal volume, tectocortical WM integrity, and tectal malformations in this population. PMID:23937233

  11. Effect of Transcranial Magnetic Stimulation (TMS) on Parietal and Premotor Cortex during Planning of Reaching Movements

    PubMed Central

    Busan, Pierpaolo; Barbera, Claudia; Semenic, Mauro; Monti, Fabrizio; Pizzolato, Gilberto; Pelamatti, Giovanna; Battaglini, Piero Paolo

    2009-01-01

    Background Cerebral activation during planning of reaching movements occurs both in the superior parietal lobule (SPL) and premotor cortex (PM), and their activation seems to take place in parallel. Methodology The activation of the SPL and PM has been investigated using transcranial magnetic stimulation (TMS) during planning of reaching movements under visual guidance. Principal Findings A facilitory effect was found when TMS was delivered on the parietal cortex at about half of the time from sight of the target to hand movement, independently of target location in space. Furthermore, at the same stimulation time, a similar facilitory effect was found in PM, which is probably related to movement preparation. Conclusions This data contributes to the understanding of cortical dynamics in the parieto-frontal network, and suggests that it is possible to interfere with the planning of reaching movements at different cortical points within a particular time window. Since similar effects may be produced at similar times on both the SPL and PM, parallel processing of visuomotor information is likely to take place in these regions. PMID:19247490

  12. The Effect of Thoracoscopic Pleurodesis in Primary Spontaneous Pneumothorax: Apical Parietal Pleurectomy versus Pleural Abrasion

    PubMed Central

    Huh, Up; Cho, Jeong Su; I, Hoseok; Lee, Jon Geun; Lee, Jun Ho

    2012-01-01

    Background The standard operative treatment of primary spontaneous pneumothorax (PSP) is thoracoscopic wedge resection, but necessity of pleurodesis still remains controversial. Nevertheless, pleural procedure after wedge resection such as pleurodesis has been performed in some patients who need an extremely low recurrence rate. Materials and Methods From January 2000 to July 2010, 207 patients who had undergone thoracoscopic wedge resection and pleurodesis were enrolled in this study. All patients were divided into two groups according to the methods of pleurodesis; apical parietal pleurectomy (group A) and pleural abrasion (group B). The recurrence after surgery had been checked by reviewing medical record through follow-up in ambulatory care clinic or calling to the patients, directly until January 2011. Results Of the 207 patients, the recurrence rate of group A and B was 9.1% and 12.8%, respectively and there was a significant difference (p=0.01, Cox's proportional hazard model). There was no significant difference in age, gender, smoking status, and body mass index between two groups. Conclusion This study suggests that the risk of recurrence after surgery in PSP is significantly low in patients who underwent thoracoscopic wedge resection with parietal pleurectomy than pleural abrasion. PMID:23130305

  13. A common prefrontal-parietal network for mnemonic and mathematical recoding strategies within working memory.

    PubMed

    Bor, Daniel; Owen, Adrian M

    2007-04-01

    Previous studies have indicated that the lateral prefrontal cortex (LPFC) is closely involved in strategic recoding, even when such processes lessen task demands. For example, 2 studies presented, in the spatial and verbal domains, sequences of stimuli for participants to retain during a short interval and then retrieve. Stimuli were either randomly arranged or structured (forming symmetries and regular shapes for the spatial task and mathematical patterns for the verbal task). Although participants performed the structured tasks better by reorganizing or "chunking" them into more efficient forms, LPFC activity was greater for the structured compared with the random sequences. However, although these results demonstrate that LPFC is involved in strategic recoding, regardless of the type of modality, it remains to be seen whether such a result generalizes to different types of strategic recoding processes. To test this, we presented digit sequence trials that separately emphasized mnemonic or mathematical recoding strategies. While participants were able to gain a performance benefit from either type of recoding strategy, increased LPFC activity was observed for both mathematical and mnemonic recoding trials, compared with either unstructured sequences or control conditions matched for mathematical or mnemonic processes. However, mathematically structured trials activated the LPFC significantly more than mnemonic recoding trials. In addition, lateral posterior parietal cortex was consistently coactivated with LPFC for strategic recoding trials, both in the current experiments and in previous related studies. We conclude that a prefrontal-parietal network is involved in strategic recoding in working memory, regardless of the type of recoding process. PMID:16707737

  14. Frontal and occipital-parietal alpha oscillations distinguish between stimulus conflict and response conflict.

    PubMed

    Tang, Dandan; Hu, Li; Lei, Yi; Li, Hong; Chen, Antao

    2015-01-01

    Conflicts between target and distraction can occur at the level of both stimulus and response processing. However, the neural oscillations underlying occurrence of the interference in different levels have not been understood well. Here, we reveal such a neural oscillation modulation by combining a 4:2 mapping design (two targets are mapped into one response key) with a practice paradigm (pretest, practice, and posttest) when healthy human participants were performing a novel color-word flanker task. Response time (RT) results revealed constant stimulus conflict (SC, stimulus incongruent minus congruent, SI-CO) but increased response conflict (RC, response incongruent minus stimulus incongruent, RI-SI) with practice. Event-related potential (ERP) results demonstrated stable P3 amplitude differences for the SI-CO in the centro-parietal region across practice, which may reflect maintenance of the stimulus processing; and significantly larger P3 amplitudes in the same region for the RI relative to SI trial type in posttest, which may reflect inhibition of the distraction response. Further, neural oscillatory results showed that with practice, the lower alpha band in the frontal region and the upper alpha band in the occipital-parietal region distinguished between stimulus- and response-conflicts, respectively, suggesting that practice reduces the alertness (sensitiveness) of the brain to conflict occurrence, and enhances stimulus-response associations. PMID:26300758

  15. A functional architecture of optic flow in the inferior parietal lobule of the behaving monkey.

    PubMed

    Raffi, Milena; Siegel, Ralph M

    2007-02-07

    The representation of navigational optic flow across the inferior parietal lobule was assessed using optical imaging of intrinsic signals in behaving monkeys. The exposed cortex, corresponding to the dorsal-most portion of areas 7a and dorsal prelunate (DP), was imaged in two hemispheres of two rhesus monkeys. The monkeys actively attended to changes in motion stimuli while fixating. Radial expansion and contraction, and rotation clockwise and counter-clockwise optic flow stimuli were presented concentric to the fixation point at two angles of gaze to assess the interrelationship between the eye position and optic flow signal. The cortical response depended upon the type of flow and was modulated by eye position. The optic flow selectivity was embedded in a patchy architecture within the gain field architecture. All four optic flow stimuli tested were represented in areas 7a and DP. The location of the patches varied across days. However the spatial periodicity of the patches remained constant across days at approximately 950 and 1100 microm for the two animals examined. These optical recordings agree with previous electrophysiological studies of area 7a, and provide new evidence for flow selectivity in DP and a fine scale description of its cortical topography. That the functional architectures for optic flow can change over time was unexpected. These and earlier results also from inferior parietal lobule support the inclusion of both static and dynamic functional architectures that define association cortical areas and ultimately support complex cognitive function.

  16. Alpha power increases in right parietal cortex reflects focused internal attention.

    PubMed

    Benedek, Mathias; Schickel, Rainer J; Jauk, Emanuel; Fink, Andreas; Neubauer, Aljoscha C

    2014-04-01

    This study investigated the functional significance of EEG alpha power increases, a finding that is consistently observed in various memory tasks and specifically during divergent thinking. It was previously shown that alpha power is increased when tasks are performed in mind-e.g., when bottom-up processing is prevented. This study aimed to examine the effect of task-immanent differences in bottom-up processing demands by comparing two divergent thinking tasks, one intrinsically relying on bottom-up processing (sensory-intake task) and one that is not (sensory-independence task). In both tasks, stimuli were masked in half of the trials to establish conditions of higher and lower internal processing demands. In line with the hypotheses, internal processing affected performance and led to increases in alpha power only in the sensory-intake task, whereas the sensory-independence task showed high levels of task-related alpha power in both conditions. Interestingly, conditions involving focused internal attention showed a clear lateralization with higher alpha power in parietal regions of the right hemisphere. Considering evidence from fMRI studies, right-parietal alpha power increases may correspond to a deactivation of the right temporoparietal junction, reflecting an inhibition of the ventral attention network. Inhibition of this region is thought to prevent reorienting to irrelevant stimulation during goal-driven, top-down behavior, which may serve the executive function of task shielding during demanding cognitive tasks such as idea generation and mental imagery.

  17. Distinct parietal and temporal connectivity profiles of ventrolateral frontal areas involved in language production.

    PubMed

    Margulies, Daniel S; Petrides, Michael

    2013-10-16

    Broca's region, which in the language-dominant hemisphere of the human brain plays a major role in language production, includes two distinct cytoarchitectonic areas: 44 and 45. The unique connectivity patterns of these two areas have not been well established. In a resting-state functional connectivity study, we tested predictions about these areas from invasive tract-tracing studies of the connectivity of their homologs in the macaque monkey. We demonstrated their distinct connectivity profiles as well as their differences from the caudally adjacent ventral parts of the premotor cortex and the primary motor cortical region that represent the orofacial musculature. Area 45 is strongly connected with the superior temporal sulcus and the cortex on the adjacent superior and middle temporal gyri. In the parietal region, area 45 is connected with the angular gyrus, whereas area 44 is connected with the supramarginal gyrus. The primary motor cortical region in the caudal precentral gyrus is not connected with the posterior parietal region, which lies outside the confines of the postcentral gyrus, whereas the ventrorostral premotor cortical area 6VR, in the most anterior part of the precentral gyrus, has strong connections with the rostral supramarginal gyrus. Thus, area 44, which has stronger connections to the posterior supramarginal gyrus, can be distinguished from both the adjacent area 6VR and area 45. These findings provide a major improvement in understanding the connectivity of the areas in the ventrolateral frontal region that are involved in language production.

  18. Damage to temporo-parietal cortex decreases incidental activation of thematic relations during spoken word comprehension

    PubMed Central

    Mirman, Daniel; Graziano, Kristen M.

    2012-01-01

    Both taxonomic and thematic semantic relations have been studied extensively in behavioral studies and there is an emerging consensus that the anterior temporal lobe plays a particularly important role in the representation and processing of taxonomic relations, but the neural basis of thematic semantics is less clear. We used eye tracking to examine incidental activation of taxonomic and thematic relations during spoken word comprehension in participants with aphasia. Three groups of participants were tested: neurologically intact control participants (N=14), individuals with aphasia resulting from lesions in left hemisphere BA 39 and surrounding temporo-parietal cortex regions (N=7), and individuals with the same degree of aphasia severity and semantic impairment and anterior left hemisphere lesions (primarily inferior frontal gyrus and anterior temporal lobe) that spared BA 39 (N=6). The posterior lesion group showed reduced and delayed activation of thematic relations, but not taxonomic relations. In contrast, the anterior lesion group exhibited longer-lasting activation of taxonomic relations and did not differ from control participants in terms of activation of thematic relations. These results suggest that taxonomic and thematic semantic knowledge are functionally and neuroanatomically distinct, with the temporo-parietal cortex playing a particularly important role in thematic semantics. PMID:22571932

  19. Parietal cell hyperplasia induced by long-term administration of antacids to rats.

    PubMed Central

    Mazzacca, G; Cascione, F; Budillon, G; D'Agostino, L; Cimino, L; Femiano, C

    1978-01-01

    Suspension of magnesium and aluminum hydroxide (30--60 mEq/24h) or a comparable volme of water was orally administered by gastric intubation to two groups of 20 male Wistar rats each over 60 days. The antacid treatment led to a significant increase in the height (0.464 +/- 0.02 mm v. 0.318 +/- 0.06) and in the volume (472 +/- 32 mm3v.328 +/- 45) of the fundic mucosa of the stomach, in the average count of parietal cells per unit area of the mucosa (32.37 +/- 1.8 v. 22.3 +/- 1.6), and in the total parietal cell population of the stomach (53.6 +/- 3.5 x 10(6) v. 43.2 +/- 3.7 x 10(6)). Furthermore fasting serum gastrin concentration was significantly higher in the antacid treated rats (81.2 +/- 7.4 pg/ml) than in control animals (56.9 +/- 6.9 pg/ml). PMID:710969

  20. Biofidelic neck influences head kinematics of parietal and occipital impacts following short falls in infants.

    PubMed

    Sullivan, Sarah; Coats, Brittany; Margulies, Susan S

    2015-09-01

    Falls are a major cause of traumatic head injury in children. Understanding head kinematics during low height falls is essential for evaluating injury risk and designing mitigating strategies. Typically, these measurements are made with commercial anthropomorphic infant surrogates, but these surrogates are designed based on adult biomechanical data. In this study, we improve upon the state-of-the-art anthropomorphic testing devices by incorporating new infant cadaver neck bending and tensile data. We then measure head kinematics following head-first falls onto 4 impact surfaces from 3 fall heights with occipital and parietal head impact locations. The biofidelic skull compliance and neck properties of the improved infant surrogate significantly influenced the measured kinematic loads, decreasing the measured impact force and peak angular accelerations, lowering the expected injury risk. Occipital and parietal impacts exhibited distinct kinematic responses in primary head rotation direction and the magnitude of the rotational velocities and accelerations, with larger angular velocities as the head rebounded after occipital impacts. Further evaluations of injury risk due to short falls should take into account the impact surface and head impact location, in addition to the fall height.

  1. Spatial selectivity in the temporoparietal junction, inferior frontal sulcus, and inferior parietal lobule.

    PubMed

    Hansen, Kathleen A; Chu, Carlton; Dickinson, Annelise; Pye, Brandon; Weller, J Patrick; Ungerleider, Leslie G

    2015-01-01

    Spatial selectivity, as measured by functional magnetic resonance imaging (fMRI) activity patterns that vary consistently with the location of visual stimuli, has been documented in many human brain regions, notably the occipital visual cortex and the frontal and parietal regions that are active during endogenous, goal-directed attention. We hypothesized that spatial selectivity also exists in regions that are active during exogenous, stimulus-driven attention. To test this hypothesis, we acquired fMRI data while subjects maintained passive fixation. At jittered time intervals, a briefly presented wedge-shaped array of rapidly expanding circles appeared at one of three contralateral or one of three ipsilateral locations. Positive fMRI activations were identified in multiple brain regions commonly associated with exogenous attention, including the temporoparietal junction, the inferior parietal lobule, and the inferior frontal sulcus. These activations were not organized as a map across the cortical surface. However, multivoxel pattern analysis of the fMRI activity correctly classified every pair of stimulus locations, demonstrating that patterns of fMRI activity were correlated with spatial location. These observations held for both contralateral and ipsilateral stimulus pairs as well as for stimuli of different textures (radial checkerboard) and shapes (squares and rings). Permutation testing verified that the obtained accuracies were not due to systematic biases and demonstrated that the findings were statistically significant. PMID:26382006

  2. Autoimmune gastritis and parietal cell reactivity in two children with abnormal intestinal permeability.

    PubMed

    Greenwood, Deanne L V; Crock, Patricia; Braye, Stephen; Davidson, Patricia; Sentry, John W

    2008-08-01

    Autoimmune gastritis is characterised by lymphocytic infiltration of the gastric submucosa, with loss of parietal and chief cells and achlorhydria. Often, gastritis is expressed clinically as cobalamin deficiency with megaloblastic anaemia, which is generally described as a disease of the elderly. Here, we report on two prepubertal children who developed autoimmune gastritis. One child developed autoimmune gastritis as part of a polyglandular autoimmune disease from a family with polyglandular autoimmune disease type II (PGA type II) and the other as part of a classic "thyro-gastric cluster," which may have been triggered by emotional trauma. Both children presented with normal small bowel biopsies, with abnormal gut permeability, which subsequently resolved. These patients are among the youngest reported to date. The immune systems targetted the gastric parietal cell autoantigens (ATP4A and ATP4B) in both children, similar to the elderly. The study of children with autoimmune gastritis and their families may provide additional insights into the disease's pathogenesis and may also lead to the identification of inheritable factors influencing susceptibility. This report underlines the necessity to screen paediatric patients with organ-specific autoimmune diseases for co-existent conditions. Children with polyglandular autoimmune disease are at particularly high risk.

  3. A Functional Architecture of Optic Flow in the Inferior Parietal Lobule of the Behaving Monkey

    PubMed Central

    Raffi, Milena; Siegel, Ralph M.

    2007-01-01

    The representation of navigational optic flow across the inferior parietal lobule was assessed using optical imaging of intrinsic signals in behaving monkeys. The exposed cortex, corresponding to the dorsal-most portion of areas 7a and dorsal prelunate (DP), was imaged in two hemispheres of two rhesus monkeys. The monkeys actively attended to changes in motion stimuli while fixating. Radial expansion and contraction, and rotation clockwise and counter-clockwise optic flow stimuli were presented concentric to the fixation point at two angles of gaze to assess the interrelationship between the eye position and optic flow signal. The cortical response depended upon the type of flow and was modulated by eye position. The optic flow selectivity was embedded in a patchy architecture within the gain field architecture. All four optic flow stimuli tested were represented in areas 7a and DP. The location of the patches varied across days. However the spatial periodicity of the patches remained constant across days at ∼950 and 1100 µm for the two animals examined. These optical recordings agree with previous electrophysiological studies of area 7a, and provide new evidence for flow selectivity in DP and a fine scale description of its cortical topography. That the functional architectures for optic flow can change over time was unexpected. These and earlier results also from inferior parietal lobule support the inclusion of both static and dynamic functional architectures that define association cortical areas and ultimately support complex cognitive function. PMID:17285147

  4. Contextual modulation of pain in masochists: involvement of the parietal operculum and insula

    PubMed Central

    Kamping, Sandra; Andoh, Jamila; Bomba, Isabelle C.; Diers, Martin; Diesch, Eugen; Flor, Herta

    2015-01-01

    Abstract Pain can be modulated by contextual stimuli, such as emotions, social factors, or specific bodily perceptions. We presented painful laser stimuli together with body-related masochistic visual stimuli to persons with and without preferred masochistic sexual behavior and used neutral, positive, and negative pictures with and without painful stimuli as control. Masochists reported substantially reduced pain intensity and unpleasantness in the masochistic context compared with controls but had unaltered pain perception in the other conditions. Functional magnetic resonance imaging revealed that masochists activated brain areas involved in sensory-discriminative processing rather than affective pain processing when they received painful stimuli on a masochistic background. The masochists compared with the controls displayed attenuated functional connectivity of the parietal operculum with the left and right insulae, the central operculum, and the supramarginal gyrus. Masochists additionally showed negative correlations between the duration of interest in masochistic activities and activation of areas involved in motor activity and affective processing. We propose that the parietal operculum serves as an important relay station that attenuates the affective-motivational aspects of pain in masochists. This novel mechanism of pain modulation might be related to multisensory integration and has important implications for the assessment and treatment of pain. PMID:26808014

  5. The eye and the hand: neural mechanisms and network models for oculomanual coordination in parietal cortex.

    PubMed

    Mascaro, Massimo; Battaglia-Mayer, Alexandra; Nasi, Lorenzo; Amit, Daniel J; Caminiti, Roberto

    2003-12-01

    The coordinated action of the eye and the hand is necessary for the successful performance of a large variety of motor tasks based on visual information. Although at the output level the neural control systems for the eye and the hand are largely segregated, in the parietal cortex of the macaque monkey there exist populations of neurons able to combine ocular and manual signals on the basis of their spatial congruence. An expression of this congruence is the clustering of eye- and hand-related preferred directions of these neurons into a restricted region of the workspace, defined as field of global tuning. This domain may represent a neural substrate for the early composition of commands for coordinated oculo-manual actions. Here we study two different prototypical network models integrating inputs about retinal target location, eye position and hand position. In the first one, we model the interaction of these different signals, as it occurs at the afferent level, in a feed-forward fashion. In the second model, we assume that recurrent interactions are responsible for their combination. Both models account surprisingly well for the experimentally observed global tuning fields of parietal neurons. When we compare them with the experimental findings, no significant difference emerges between the two. Experiments potentially able to discriminate between these models could be performed.

  6. Spatial effects of shifting prisms on properties of posterior parietal cortex neurons.

    PubMed

    Karkhanis, Anushree N; Heider, Barbara; Silva, Fabian Muñoz; Siegel, Ralph M

    2014-08-15

    The posterior parietal cortex contains neurons that respond to visual stimulation and motor behaviour. The objective of the current study was to test short-term adaptation in neurons in macaque area 7a and the dorsal prelunate during visually guided reaching using Fresnel prisms that displaced the visual field. The visual perturbation shifted the eye position and created a mismatch between perceived and actual reach location. Two non-human primates were trained to reach to visual targets before, during and after prism exposure while fixating the reach target in different locations. They were required to reach to the physical location of the reach target and not the perceived, displaced location. While behavioural adaptation to the prisms occurred within a few trials, the majority of neurons responded to the distortion either with substantial changes in spatial eye position tuning or changes in overall firing rate. These changes persisted even after prism removal. The spatial changes were not correlated with the direction of induced prism shift. The transformation of gain fields between conditions was estimated by calculating the translation and rotation in Euler angles. Rotations and translations of the horizontal and vertical spatial components occurred in a systematic manner for the population of neurons suggesting that the posterior parietal cortex retains a constant representation of the visual field remapping between experimental conditions.

  7. Functional heterogeneity of inferior parietal cortex during mathematical cognition assessed with cytoarchitectonic probability maps.

    PubMed

    Wu, S S; Chang, T T; Majid, A; Caspers, S; Eickhoff, S B; Menon, V

    2009-12-01

    Although the inferior parietal cortex (IPC) has been consistently implicated in mathematical cognition, the functional roles of its subdivisions are poorly understood. We address this problem using probabilistic cytoarchitectonic maps of IPC subdivisions intraparietal sulcus (IPS), angular gyrus (AG), and supramarginal gyrus. We quantified IPC responses relative to task difficulty and individual differences in task proficiency during mental arithmetic (MA) tasks performed with Arabic (MA-A) and Roman (MA-R) numerals. The 2 tasks showed similar levels of activation in 3 distinct IPS areas, hIP1, hIP2, and hIP3, suggesting their obligatory role in MA. Both AG areas, PGa and PGp, were strongly deactivated in both tasks, with stronger deactivations in posterior area PGp. Compared with the more difficult MA-R task, the MA-A task showed greater responses in both AG areas, but this effect was driven by less deactivation in the MA-A task. AG deactivations showed prominent overlap with lateral parietal nodes of the default mode network, suggesting a nonspecific role in MA. In both tasks, greater bilateral AG deactivation was associated with poorer performance. Our findings suggest a close link between IPC structure and function and they provide new evidence for behaviorally salient functional heterogeneity within the IPC during mathematical cognition. PMID:19406903

  8. Parietal cortex coding of limb posture: in search of the body-schema.

    PubMed

    Parkinson, Amy; Condon, Laura; Jackson, Stephen R

    2010-09-01

    Computational theories of motor control propose that the brain uses 'forward' models of the body to ensure accurate control of movements. Forward 'dynamic' models are thought to generate an estimate of the next motor state for an upcoming movement: thereby providing a dynamic representation of the current postural configuration of the body that can be utilised during movement planning and execution. We used event-related functional magnetic resonance imaging [fMRI] to investigate brain areas involved in maintaining and updating the postural representations of the upper limb that participate in the control of reaching movements. We demonstrate that the neural correlates for executing memory-guided reaching movements to unseen target locations that were defined by arm posture, are primarily within regions of the superior parietal lobule [SPL]: including an area of the medial SPL identified as the human homologue of the 'parietal reach region' [PRR]. Using effective connectivity analyses we show that signals that influence the BOLD response within this area originate within premotor areas of the frontal lobe, including premotor cortex and the supplementary motor area. These data are consistent with the view that the SPL maintains an up-to-date estimate of the current postural configuration of the arm that is used during the planning and execution of reaching movements.

  9. Emotion unfolded by motion: a role for parietal lobe in decoding dynamic facial expressions.

    PubMed

    Sarkheil, Pegah; Goebel, Rainer; Schneider, Frank; Mathiak, Klaus

    2013-12-01

    Facial expressions convey important emotional and social information and are frequently applied in investigations of human affective processing. Dynamic faces may provide higher ecological validity to examine perceptual and cognitive processing of facial expressions. Higher order processing of emotional faces was addressed by varying the task and virtual face models systematically. Blood oxygenation level-dependent activation was assessed using functional magnetic resonance imaging in 20 healthy volunteers while viewing and evaluating either emotion or gender intensity of dynamic face stimuli. A general linear model analysis revealed that high valence activated a network of motion-responsive areas, indicating that visual motion areas support perceptual coding for the motion-based intensity of facial expressions. The comparison of emotion with gender discrimination task revealed increased activation of inferior parietal lobule, which highlights the involvement of parietal areas in processing of high level features of faces. Dynamic emotional stimuli may help to emphasize functions of the hypothesized 'extended' over the 'core' system for face processing.

  10. Spatial selectivity in the temporoparietal junction, inferior frontal sulcus, and inferior parietal lobule

    PubMed Central

    Hansen, Kathleen A.; Chu, Carlton; Dickinson, Annelise; Pye, Brandon; Weller, J. Patrick; Ungerleider, Leslie G.

    2015-01-01

    Spatial selectivity, as measured by functional magnetic resonance imaging (fMRI) activity patterns that vary consistently with the location of visual stimuli, has been documented in many human brain regions, notably the occipital visual cortex and the frontal and parietal regions that are active during endogenous, goal-directed attention. We hypothesized that spatial selectivity also exists in regions that are active during exogenous, stimulus-driven attention. To test this hypothesis, we acquired fMRI data while subjects maintained passive fixation. At jittered time intervals, a briefly presented wedge-shaped array of rapidly expanding circles appeared at one of three contralateral or one of three ipsilateral locations. Positive fMRI activations were identified in multiple brain regions commonly associated with exogenous attention, including the temporoparietal junction, the inferior parietal lobule, and the inferior frontal sulcus. These activations were not organized as a map across the cortical surface. However, multivoxel pattern analysis of the fMRI activity correctly classified every pair of stimulus locations, demonstrating that patterns of fMRI activity were correlated with spatial location. These observations held for both contralateral and ipsilateral stimulus pairs as well as for stimuli of different textures (radial checkerboard) and shapes (squares and rings). Permutation testing verified that the obtained accuracies were not due to systematic biases and demonstrated that the findings were statistically significant. PMID:26382006

  11. Posterior Parietal Cortex Drives Inferotemporal Activations During Three-Dimensional Object Vision

    PubMed Central

    Van Dromme, Ilse C.; Premereur, Elsie; Verhoef, Bram-Ernst; Vanduffel, Wim; Janssen, Peter

    2016-01-01

    The primate visual system consists of a ventral stream, specialized for object recognition, and a dorsal visual stream, which is crucial for spatial vision and actions. However, little is known about the interactions and information flow between these two streams. We investigated these interactions within the network processing three-dimensional (3D) object information, comprising both the dorsal and ventral stream. Reversible inactivation of the macaque caudal intraparietal area (CIP) during functional magnetic resonance imaging (fMRI) reduced fMRI activations in posterior parietal cortex in the dorsal stream and, surprisingly, also in the inferotemporal cortex (ITC) in the ventral visual stream. Moreover, CIP inactivation caused a perceptual deficit in a depth-structure categorization task. CIP-microstimulation during fMRI further suggests that CIP projects via posterior parietal areas to the ITC in the ventral stream. To our knowledge, these results provide the first causal evidence for the flow of visual 3D information from the dorsal stream to the ventral stream, and identify CIP as a key area for depth-structure processing. Thus, combining reversible inactivation and electrical microstimulation during fMRI provides a detailed view of the functional interactions between the two visual processing streams. PMID:27082854

  12. Parietal subdural empyema as complication of acute odontogenic sinusitis: a case report

    PubMed Central

    2014-01-01

    Introduction To date intracranial complication caused by tooth extractions are extremely rare. In particular parietal subdural empyema of odontogenic origin has not been described. A literature review is presented here to emphasize the extreme rarity of this clinical entity. Case presentation An 18-year-old Caucasian man with a history of dental extraction developed dysarthria, lethargy, purulent rhinorrhea, and fever. A computed tomography scan demonstrated extensive sinusitis involving maxillary sinus, anterior ethmoid and frontal sinus on the left side and a subdural fluid collection in the temporal-parietal site on the same side. He underwent vancomycin, metronidazole and meropenem therapy, and subsequently left maxillary antrostomy, and frontal and maxillary sinuses toilette by an open approach. The last clinical control done after 3 months showed a regression of all symptoms. Conclusions The occurrence of subdural empyema is an uncommon but possible sequela of a complicated tooth extraction. A multidisciplinary approach involving otolaryngologist, neurosurgeons, clinical microbiologist, and neuroradiologist is essential. Antibiotic therapy with surgical approach is the gold standard treatment. PMID:25146384

  13. Parietal Bone Thickness and Vascular Diameters in Adult Modern Humans: A Survey on Cranial Remains.

    PubMed

    Eisová, Stanislava; Rangel de Lázaro, Gizéh; Píšová, Hana; Pereira-Pedro, Sofia; Bruner, Emiliano

    2016-07-01

    Cranial bone thickness varies among modern humans, and many factors influencing this variability remain unclear. Growth hormones and physical activity are thought to influence the vault thickness. Considering that both systemic factors and energy supply influence the vascular system, and taking into account the structural and biomechanical interaction between endocranial vessels and vault bones, in this study we evaluate the correlation between vascular and bone diameters. In particular, we tested the relationship between the thickness of the parietal bone (which is characterized, in modern humans, by a complex vascular network) and the lumen size of the middle meningeal and diploic vessels, in adult modern humans. Our results show no patent correlation between the thickness of parietal bone and the size of the main vascular channels. Values and distributions of the branching patterns, as well as anatomical relationships between vessels and bones, are also described in order to provide information concerning the arrangement of the endocranial vascular morphology. This information is relevant in both evolutionary and medical contexts. Anat Rec, 299:888-896, 2016. © 2016 Wiley Periodicals, Inc. PMID:27072555

  14. FURTHER OBSERVATIONS ON THE FINE STRUCTURE OF THE PARIETAL EYE OF LIZARDS

    PubMed Central

    Eakin, Richard M.; Westfall, Jane A.

    1960-01-01

    An electron microscopical study of the third eye of the Western Fence Lizard, Sceloporus occidentalis, fixed with 1 per cent osmium tetroxide, pH 7.4–7.6, for 16 to 20 hours at 0°C., revealed the following new facts. The fibrillar system of the retinal photoreceptor consists of nine double fibrils enclosed in a sheath. Pigment cells and lens cells possess similar systems. Two short cylindrical centrioles are associated with the fibrillar apparatus: one, from which striated rootlets extend inward, lies at the base of the fibrils, with the other at an oblique angle to the axis of the system. A Golgi complex, whorls of endoplasmic reticulum, lipid (?) droplets, and other organelles and inclusions in the photoreceptors are described. An axon leads from the base of the photoreceptor into the nervous layer of the retina which consists of many nerve fibers and large ganglion cells. Although the pattern of neural connections has not yet been determined, some synapses were found. The parietal nerve consists of about 250 non-medullated fibers. The capsule of the eye usually has a layer of iridocytes, which contain rows of guanine (?) rods. A few parietal eyes of the Granite Night Lizard, Xantusia henshawi, were also examined. Large lipid (?) droplets occur in the bases of their receptoral processes. PMID:13725484

  15. Biofidelic neck influences head kinematics of parietal and occipital impacts following short falls in infants

    PubMed Central

    Sullivan, Sarah; Coats, Brittany; Margulies, Susan S.

    2015-01-01

    Falls are a major cause of traumatic head injury in children. Understanding head kinematics during low height falls is essential for evaluating injury risk and designing mitigating strategies. Typically, these measurements are made with commercial anthropomorphic infant surrogates, but these surrogates are designed based on adult biomechanical data. In this study, we improve upon the state-of-the-art anthropomorphic testing devices by incorporating new infant cadaver neck bending and tensile data. We then measure head kinematics following head-first falls onto 4 impact surfaces from 3 fall heights with occipital and parietal head impact locations. The biofidelic skull compliance and neck properties of the improved infant surrogate significantly influenced the measured kinematic loads, decreasing the measured impact force and peak angular accelerations, lowering the expected injury risk. Occipital and parietal impacts exhibited distinct kinematic responses in primary head rotation direction and the magnitude of the rotational velocities and accelerations, with larger angular velocities as the head rebounded after occipital impacts. Further evaluations of injury risk due to short falls should take into account the impact surface and head impact location, in addition to the fall height. PMID:26072183

  16. Size abnormalities of the superior parietal cortices are related to dissociation in borderline personality disorder.

    PubMed

    Irle, Eva; Lange, Claudia; Weniger, Godehard; Sachsse, Ulrich

    2007-11-15

    Recent evidence suggests that borderline personality disorder (BPD) is related to reduced size of the parietal lobe. Dissociative symptoms occur in the majority of individuals with BPD. Structural magnetic resonance imaging (3D-MRI) was used to assess volumes of the superior (precuneus, postcentral gyrus) and inferior parietal cortices in 30 young women with BPD who had been exposed to severe childhood sexual and physical abuse and 25 healthy control subjects. Compared with control subjects, BPD subjects had significantly smaller right-sided precuneus (-9%) volumes. The left postcentral gyrus of BPD subjects with the comorbid diagnosis of dissociative amnesia (DA) or dissociative identity disorder (DID) was significantly increased compared with controls (+13%) and compared with BPD subjects without these disorders (+11%). In BPD subjects, stronger depersonalization was significantly related to larger right precuneus size. Possibly, larger precuneus size in BPD is related to symptoms of depersonalization. Increased postcentral gyrus size in BPD may be related to the development of DA or DID in the presence of severe childhood abuse.

  17. Reduced glucose metabolism in temporo-parietal cortices of women with borderline personality disorder.

    PubMed

    Lange, Claudia; Kracht, Lutz; Herholz, Karl; Sachsse, Ulrich; Irle, Eva

    2005-07-30

    Individuals with borderline personality disorder (BPD) and posttraumatic stress disorder (PTSD) often experience dissociative symptoms. Evidence is increasing that stress-related hyperglutamatergic states may contribute to dissociative symptoms and neurodegeneration in temporo-parietal cortical areas. Seventeen young women with BPD who had been exposed to severe childhood physical/sexual abuse and presented with pronounced dissociative symptoms underwent (18)fluoro-2-deoxyglucose positron emission tomography (FDG-PET). Nine healthy, matched volunteers served as comparison subjects. Borderline subjects displayed reduced FDG uptake (as analyzed by SPM) in the right temporal pole/anterior fusiform gyrus and in the left precuneus and posterior cingulate cortex. Impaired memory performance among borderline subjects was significantly correlated with metabolic activity in ventromedial and lateral temporal cortices. Our results demonstrate regional hypometabolism in temporal and medial parietal cortical regions known to be involved in episodic memory consolidation and retrieval. Currently, the precuneus/posterior cingulate cortex is modeled as part of a network of tonically active brain regions that continuously gather information about the world around and within us. Decreased resting metabolic rate of these regions may reflect dissociative symptoms and possibly also identity disturbances and interpersonal difficulties of individuals with BPD.

  18. Normalization of sonographical multifocal nerve enlargements in a MADSAM patient following a good clinical response to intravenous immunoglobulin.

    PubMed

    Tanaka, Kanta; Ota, Natsuko; Harada, Yuzuru; Wada, Ikko; Suenaga, Toshihiko

    2016-09-01

    Focal nerve enlargements at sites of conduction blocks can be visualized sonographically in patients with multifocal acquired demyelinating sensory and motor neuropathy (MADSAM). However, little is known about association between nerve morphological changes and treatment responses. Here we present a 73-year-old female MADSAM patient whose sonographical multifocal nerve enlargements normalized following a good treatment response. She was admitted to our department with progressive asymmetrical muscle weakness and sensory disturbances for 6 months. Ultrasonography revealed multifocal nerve enlargements at sites of electrophysiological demyelination. Intravenous immunoglobulin improved her symptoms and electrophysiological abnormalities. Six months later, ultrasonography revealed normalization of multifocal nerve enlargements. Contrary to our observations, one previous report described a MADSAM patient with persistent nerve enlargements at the sites of resolved conduction blocks. In this earlier patient, however, the time from onset to remission was approximately 30 months. Morphological changes of nerve enlargements in MADSAM may vary with treatment response. PMID:27460345

  19. Does shape discrimination by the mouth activate the parietal and occipital lobes? - near-infrared spectroscopy study.

    PubMed

    Kagawa, Tomonori; Narita, Noriyuki; Iwaki, Sunao; Kawasaki, Shingo; Kamiya, Kazunobu; Minakuchi, Shunsuke

    2014-01-01

    A cross-modal association between somatosensory tactile sensation and parietal and occipital activities during Braille reading was initially discovered in tests with blind subjects, with sighted and blindfolded healthy subjects used as controls. However, the neural background of oral stereognosis remains unclear. In the present study, we investigated whether the parietal and occipital cortices are activated during shape discrimination by the mouth using functional near-infrared spectroscopy (fNIRS). Following presentation of the test piece shape, a sham discrimination trial without the test pieces induced posterior parietal lobe (BA7), extrastriate cortex (BA18, BA19), and striate cortex (BA17) activation as compared with the rest session, while shape discrimination of the test pieces markedly activated those areas as compared with the rest session. Furthermore, shape discrimination of the test pieces specifically activated the posterior parietal cortex (precuneus/BA7), extrastriate cortex (BA18, 19), and striate cortex (BA17), as compared with sham sessions without a test piece. We concluded that oral tactile sensation is recognized through tactile/visual cross-modal substrates in the parietal and occipital cortices during shape discrimination by the mouth.

  20. Polarized distribution of IQGAP proteins in gastric parietal cells and their roles in regulated epithelial cell secretion.

    PubMed

    Zhou, Rihong; Guo, Zhen; Watson, Charles; Chen, Emily; Kong, Rong; Wang, Wenxian; Yao, Xuebiao

    2003-03-01

    Actin cytoskeleton plays an important role in the establishment of epithelial cell polarity. Cdc42, a member of Rho GTPase family, modulates actin dynamics via its regulators, such as IQGAP proteins. Gastric parietal cells are polarized epithelial cells in which regulated acid secretion occurs in the apical membrane upon stimulation. We have previously shown that actin isoforms are polarized to different membrane domains and that the integrity of the actin cytoskeleton is essential for acid secretion. Herein, we show that Cdc42 is preferentially distributed to the apical membrane of gastric parietal cells. In addition, we revealed that two Cdc42 regulators, IQGAP1 and IQGAP2, are present in gastric parietal cells. Interestingly, IQGAP2 is polarized to the apical membrane of the parietal cells, whereas IQGAP1 is mainly distributed to the basolateral membrane. An IQGAP peptide that competes with full-length IQGAP proteins for Cdc42-binding in vitro also inhibits acid secretion in streptolysin-O-permeabilized gastric glands. Furthermore, this peptide disrupts the association of IQGAP and Cdc42 with the apical actin cytoskeleton and prevents the apical membrane remodeling upon stimulation. We propose that IQGAP2 forms a link that associates Cdc42 with the apical cytoskeleton and thus allows for activation of polarized secretion in gastric parietal cells.

  1. Reduced alpha-gamma phase amplitude coupling over right parietal cortex is associated with implicit visuomotor sequence learning.

    PubMed

    Tzvi, Elinor; Verleger, Rolf; Münte, Thomas F; Krämer, Ulrike M

    2016-11-01

    Implicit visuomotor sequence learning is important for our daily life, e.g., when writing or playing an instrument. Previous research identified a network of cortical regions that is relevant for motor sequence learning, namely primary motor cortex, premotor cortex, superior parietal cortex, and subcortical regions, including basal ganglia and cerebellum. Here, we investigated learning-related changes in oscillatory activity (theta, alpha and gamma power) and cross-frequency interactions (theta- and alpha-gamma phase-amplitude coupling) within cortical regions during sensorimotor memory formation. EEG was recorded from a large group of participants (n=73) performing the serial reaction time task (SRTT). Posterior parietal alpha power was larger early-on during sequence learning and smaller in later sessions. Alpha/low-gamma (8-13Hz and 30-48Hz) phase-amplitude coupling (PAC) was significantly smaller during sequence learning over right superior parietal cortex and frontal cortex. During the transition from sequential stimuli to random stimuli, participants made more errors, indicating that they still implicitly attempted to implement the learned motor sequence. At the same time, alpha/low-gamma phase-amplitude coupling was found to be smaller during the transition relative to later random trials. Our results show that learning and implementing a learned motor sequence reduces alpha/low-gamma PAC over parietal and frontal cortex. Fronto-parietal alpha/low-gamma PAC might be relevant for visuomotor mapping which becomes less relevant once the motor sequence has been encoded. PMID:27403869

  2. Enlarged prostate

    MedlinePlus

    ... Possible side effects include decreased sex drive and impotence . Antibiotics may be prescribed to treat chronic prostatitis ( ... less-invasive procedures carry a lower risk for impotence and incontinence than TURP, although the risk with ...

  3. NATO Enlargement.

    ERIC Educational Resources Information Center

    Volker, Karen

    1998-01-01

    Reviews the history of the North Atlantic Treaty Organization (NATO) and describes the debate over expanding its membership. Includes a discussion of the process for adding NATO members and a copy of the treaty. Suggests several exercises to help students better understand the NATO-expansion debate. (DSK)

  4. Enlarged Tonsils

    Cancer.gov

    A cohort of about 3,000 individuals who were irradiated during childhood for benign head and neck conditions at Michael Reese Hospital was assembled and monitored for the risk of thyroid and other cancers.

  5. Diaphragmatic hernia and right-sided heart enlargement in a Florida manatee (Trichechus manatus latirostris).

    PubMed

    Gerlach, Trevor J; de Wit, Martine; Landolfi, Jennifer A

    2012-10-01

    Postmortem evaluation of a Florida manatee (Trichechus manatus latirostris) revealed cold stress lesions and previous watercraft trauma that included broken ribs, a diaphragmatic hernia, an enlarged vena cava, and right-sided cardiomegaly. We discuss these findings and present a possible pathogenesis for the cardiomegaly.

  6. Airway obstruction caused by rapid enlargement of cervical lymphangioma in a five-month-old boy.

    PubMed

    Shimizu, Junji; Taga, Takashi; Kishimoto, Takuma; Ohta, Motoki; Tagawa, Kouji; Kunitsu, Tomoaki; Yamane, Tetsunobu; Tsujita, Yasuyuki; Kubota, Yoshihiro; Eguchi, Yutaka

    2016-09-01

    Cervical lymphangioma can cause airway obstruction secondary to enlargement following infection. Physicians should be aware that the airway obstruction can progress rapidly when patients with cervical lymphangioma have respiratory symptoms. Sclerotherapy for lymphangioma can cause both transient swelling and airway obstruction; thus, prophylactic and elective tracheostomy should be considered. PMID:27648270

  7. Nitrogen dioxide regulates organ growth by controlling cell proliferation and enlargement in Arabidopsis.

    PubMed

    Takahashi, Misa; Furuhashi, Takamasa; Ishikawa, Naoko; Horiguchi, Gorou; Sakamoto, Atsushi; Tsukaya, Hirokazu; Morikawa, Hiromichi

    2014-03-01

    • To gain more insight into the physiological function of nitrogen dioxide (NO₂), we investigated the effects of exogenous NO₂ on growth in Arabidopsis thaliana. • Plants were grown in air without NO₂ for 1 wk after sowing and then grown for 1-4 wk in air with (designated treated plants) or without (control plants) NO₂. Plants were irrigated semiweekly with a nutrient solution containing 19.7 mM nitrate and 10.3 mM ammonium. • Five-week-old plants treated with 50 ppb NO₂ showed a ≤ 2.8-fold increase in biomass relative to controls. Treated plants also showed early flowering. The magnitude of the effects of NO₂ on leaf expansion, cell proliferation and enlargement was greater in developing than in maturing leaves. Leaf areas were 1.3-8.4 times larger on treated plants than corresponding leaves on control plants. The NO₂-induced increase in leaf size was largely attributable to cell proliferation in developing leaves, but was attributable to both cell proliferation and enlargement in maturing leaves. The expression of different sets of genes for cell proliferation and/or enlargement was induced by NO₂, but depended on the leaf developmental stage. • Collectively, these results indicated that NO₂ regulates organ growth by controlling cell proliferation and enlargement.

  8. 22. Photographic copy enlargement from a 4x5 copy negative of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. Photographic copy enlargement from a 4x5 copy negative of a print. (Original print located on abandoned NASA site, currently owned by the City of Downey, Downey, California). 1954 USAF PLANT 16 AERIAL BUILDING 41 NORTH TO SOUTH. - NASA Industrial Plant, Missile Research Laboratory, 12214 Lakewood Boulevard, Downey, Los Angeles County, CA

  9. 9. Photographic copy enlargement from a 4x5 copy negative. (Original ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Photographic copy enlargement from a 4x5 copy negative. (Original drawing located on abandoned NASA site, currently owned by the City of Downey, Downey, California). 1976 BLDGS.25, 41 SITE PLAN. - NASA Industrial Plant, Storage Facility, 12214 Lakewood Boulevard, Downey, Los Angeles County, CA

  10. 19. (4"X5" image enlarged from 2 1/4" negative) Sam Fowler, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. (4"X5" image enlarged from 2 1/4" negative) Sam Fowler, Photographer, February 1998 VIEW OF GEORGIA DOT BRIDGE NO. 051-00025D-01986N (JAMES P. HOULIHAN BRIDGE). NAVIGATIONAL LIGHT LOCATED ON TOP OF FENDER - Georgia DOT Bridge No. 051-00025D-01986N, US 17 & State Route 25 Spanning Savannah River, Port Wentworth, Chatham County, GA

  11. 4. Photocopy of photograph (enlargement of NJ1623). View looking northeast, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Photocopy of photograph (enlargement of NJ-162-3). View looking northeast, showing vessel 53 (Minerva, formerly Jane Moselery) in foreground with side wheels and vessel 54 (package freighter) beside it. Circa 1940, from The Staten Island Advance, photographer not stated. (Original in Staten Island Historic Society, Staten Island, New York) - Shooters Island, Ships Graveyard, Newark Bay, Staten Island (subdivision), Richmond County, NY

  12. Diaphragmatic hernia and right-sided heart enlargement in a Florida manatee (Trichechus manatus latirostris).

    PubMed

    Gerlach, Trevor J; de Wit, Martine; Landolfi, Jennifer A

    2012-10-01

    Postmortem evaluation of a Florida manatee (Trichechus manatus latirostris) revealed cold stress lesions and previous watercraft trauma that included broken ribs, a diaphragmatic hernia, an enlarged vena cava, and right-sided cardiomegaly. We discuss these findings and present a possible pathogenesis for the cardiomegaly. PMID:23060518

  13. Cytochrome P450 2C9 gene polymorphism in phenytoin induced gingival enlargement: A case report.

    PubMed

    Babu, S P K Kennedy; Ramesh, V; Samidorai, Agila; Charles, N S C

    2013-07-01

    Gingival enlargement comprises any clinical condition in which an increase in the size of the gingiva is observed. Among the drugs that induce gingival enlargement, the antiepileptic agent phenytoin has been widely related to this condition. The Cytochrome P450(CYP) superfamily is the most commonly involved enzymes in metabolism of drugs. Common coding region CYP variants that affects drug elimination and response has been studied in great detail. Pharmacogenetic influences on drug metabolism have been widely reviewed and gene polymorphism of cytochrome P450 2C9 appeared to be responsible for much of the interindividual variability on drug elimination. Genetic variation in the CYP2C9 gene can affect metabolism, leading to altered phenotypes. Individuals with poor metaboliser alleles of CYP2C9 gene were shown to have a reduced metabolism of phenytoin compared with wild-type alleles. Thus identification of patients genotype prior to anti-epileptic drug administration could potentially prevent higher serum drug concentrations leading to adverse side effects such as gingival enlargement. This case report addresses the influence of CYP2C9 genetic polymorphism on Phenytoin drug metabolism thereby causing gingival enlargement. PMID:24082701

  14. CAFETERIA, TRA616. MODIFICATIONS ENLARGED SEATING AND WORK AREAS IN 1957. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CAFETERIA, TRA-616. MODIFICATIONS ENLARGED SEATING AND WORK AREAS IN 1957. FLOOR PLAN. WALL BETWEEN CAFETERIA AND WAREHOUSE SECTIONS. C.A. SUNDBERG AND ASSOCIATES 884-MTR-616-A-2, 12/1956. INL INDEX NO. 531-0616-00-822-101880, REV. 4. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  15. 46 CFR 502.228 - Request for enlargement of time for filing exceptions and replies thereto.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ADMINISTRATIVE PROVISIONS RULES OF PRACTICE AND PROCEDURE Briefs; Requests for Findings; Decisions; Exceptions... of the time fixed for the filing of such documents. Any enlargement of time granted will automatically extend by the same period the date for the filing of notice or review by the Commission....

  16. INDIUM AND ZINC MEDIATED ONE-ATOM CARBOCYCLE ENLARGEMENT IN WATER. (R822668)

    EPA Science Inventory

    Abstract

    Six-, seven-, eight-membered rings are enlarged by one carbon-atom into seven-, eight- and nine-membered ring derivatives respectively, via indium or zinc mediated reactions in aqueous medium.

  17. 23. Photographic copy enlargement from a 4x5 copy negative of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Photographic copy enlargement from a 4x5 copy negative of a drawing (Original drawing located on abandoned NASA site, currently owned by the City of Downey, Downey, Calfornia). JANUARY 1960 USAF PLANT 16 MASTER PLOT AND GRID PLAN. - NASA Industrial Plant, Missile Research Laboratory, 12214 Lakewood Boulevard, Downey, Los Angeles County, CA

  18. Reflex receptive fields are enlarged in patients with musculoskeletal low back and neck pain.

    PubMed

    Biurrun Manresa, José A; Neziri, Alban Y; Curatolo, Michele; Arendt-Nielsen, Lars; Andersen, Ole K

    2013-08-01

    Pain hypersensitivity has been consistently detected in chronic pain conditions, but the underlying mechanisms are difficult to investigate in humans and thus poorly understood. Patients with endometriosis pain display enlarged reflex receptive fields (RRF), providing a new perspective in the identification of possible mechanisms behind hypersensitivity states in humans. The primary hypothesis of this study was that RRF are enlarged in patients with musculoskeletal pain. Secondary study end points were subjective pain thresholds and nociceptive withdrawal reflex (NWR) thresholds after single and repeated (temporal summation) electrical stimulation. Forty chronic neck pain patients, 40 chronic low back pain patients, and 24 acute low back pain patients were tested. Electrical stimuli were applied to 10 sites on the sole of the foot to quantify the RRF, defined as the area of the foot from where a reflex was evoked. For the secondary end points, electrical stimuli were applied to the cutaneous innervation area of the sural nerve. All patient groups presented enlarged RRF areas compared to pain-free volunteers (P<.001). Moreover, they also displayed lower NWR and pain thresholds to single and repeated electrical stimulation (P<.001). These results demonstrate that musculoskeletal pain conditions are characterized by enlarged RRF, lowered NWR and pain thresholds, and facilitated temporal summation, most likely caused by widespread spinal hyperexcitability. This study contributes to a better understanding of the mechanisms underlying these pain conditions, and it supports the use of the RRF and NWR as objective biomarkers for pain hypersensitivity in clinical and experimental pain research. PMID:23707309

  19. 16. Photocopy of drawing enlarged from a 4x5 negative (from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. Photocopy of drawing enlarged from a 4x5 negative (from Cultural Resources plan files, Gateway National Recreation Area, New Jersey) U.S. Army Corps of Engineers, Designers, 1909 PLAN OF DRAINAGE AND ELECTRICAL SYSTEM OF BATTERY - Fort Hancock, Battery George Arrowsmith, Southwest edge of Sandy Point extending to Horseshoe Cove, Fort Hancock, Monmouth County, NJ

  20. Calcium localization and tipburn development in lettuce leaves during early enlargement

    NASA Technical Reports Server (NTRS)

    Barta, D. J.; Tibbitts, T. W.

    2000-01-01

    Tissue concentrations of Ca, Mg, and K were determined across immature leaves of lettuce (Lactuca sativa L. 'Buttercrunch') at different stages of enlargement using electron microprobe x-ray analysis. The analysis was with a wavelength dispersive spectrometer to permit detection of low concentrations of Ca. Patterns of mineral accumulation in immature leaves that were exposed were compared to patterns of accumulation in leaves that were enclosed within a developing head. The leaves developing without enclosure were free to transpire and developed normally whereas leaves developing with enclosure were restricted in transpiration and developed an injury that was characteristic of Ca deficiency. In the exposed leaves, Ca concentrations increased from an average of 1.0 to 2.1 mg g-1 dry weight (DW) as the leaves enlarged from 5 to 30 mm in length. In the enclosed leaves, Ca concentrations decreased from 1.0 to 0.7 mg g-1 DW as the leaves enlarged from 5 to 30 mm in length. At the tips of these enclosed leaves a larger decrease was found, from 0.9 to 0.3 mg g-1 DW during enlargement. Necrotic injury first became apparent in this tip area when the concentration was approximate to 0.4 mg g-1 DW. Magnesium concentrations across the exposed leaves were similar to concentrations across the enclosed leaves, and did not change with enlargement. Magnesium concentrations averaged 3.5. mg g-1 DW in both enclosed and exposed leaves during enlargement from 5 to 30 mm. In both exposed and enclosed leaves, K concentrations increased during enlargement from 40 to approximate to 60 mg g-1 DW. Potassium concentrations were highest toward the leaf apex and upper margin where injury symptoms occurred, and this may have enhanced injury development. This research documents the critical low levels of Ca (0.2 to 0.4 mg g-1 DW) that can occur in enclosed leaves of plants and which apparently leads to the marginal apex necrosis of developing leaves seen frequently on lettuce and other crops.

  1. Morphology and morphometry of the human sublingual glands in mouth floor enlargements of edentulous patients

    PubMed Central

    de SÁ, Josiane Costa Rodrigues; TOLENTINO, Elen de Souza; AZEVEDO-ALANIS, Luciana Reis; IWAKI FILHO, Liogi; LARA, Vanessa Soares; DAMANTE, José Humberto

    2013-01-01

    Asymptomatic mouth floor enlargements may be observed in edentulous patients. These masses, which protrude from the mouth floor, may complicate the fitting of dentures and require surgery. Whether this "entity" may be considered an anatomical variation of the mouth floor or represent specific alterations in the sublingual gland is not known. Objective The aim of this work is to investigate the morphological and morphometric aspects of the sublingual glands of edentulous patients with mouth floor enlargements and compare the glands of these patients with the sublingual glands of human cadavers. Material and Methods Microscopic evaluation was performed on human sublingual glands from edentulous patients with mouth floor enlargements (n=20) and edentulous cadavers (n=20). The patients and cadavers were of similar ages. The data were compared using Mann-Whitney U, Fisher's exact and Student's t tests (p<0.05). Results Acinar atrophy, duct-like structures, mononuclear infiltrates, replacement of parenchyma with fibrous/adipose tissue, mucous extravasation and oncocytosis were similar between the groups (p>0.05). Only the variables "autolysis" and "congested blood vessels" presented statistical difference between groups (p=0.014; p=0.043). The morphometric study revealed that the volume densities of acini, ducts, stroma and adipose tissue were similar between the groups (p>0.05). Conclusion The microscopic characteristics of the sublingual glands in mouth floor enlargements in edentulous patients correspond to characteristics associated with the normal aging process. The glands are not pathological and represent an age-related alteration that occurs with or without the presence of the mouth floor enlargements. PMID:24473720

  2. Improving the Effect and Efficiency of FMD Control by Enlarging Protection or Surveillance Zones

    PubMed Central

    Halasa, Tariq; Toft, Nils; Boklund, Anette

    2015-01-01

    An epidemic of foot-and-mouth disease (FMD) in a FMD-free country with large exports of livestock and livestock products would result in profound economic damage. This could be reduced by rapid and efficient control of the disease spread. The objectives of this study were to estimate the economic impact of a hypothetical FMD outbreak in Denmark based on changes to the economic assumptions of the model, and to investigate whether the control of an FMD epidemic can be improved by combining the enlargement of protection or surveillance zones with pre-emptive depopulation or emergency vaccination. The stochastic spatial simulation model DTU-DADS was used to simulate the spread of FMD in Denmark. The control strategies were the basic EU and Danish strategy, pre-emptive depopulation, suppressive or protective vaccination, enlarging protection or surveillance zones, and a combination of pre-emptive depopulation or emergency vaccination with enlarged protection or surveillance zones. Herds are detected either based on basic detection through the appearance of clinical signs, or as a result of surveillance in the control zones. The economic analyses consisted of direct costs and export losses. Sensitivity analysis was performed on uncertain and potentially influential input parameters. Enlarging the surveillance zones from 10 to 15 km, combined with pre-emptive depopulation over a 1-km radius around detected herds resulted in the lowest total costs. This was still the case even when the different input parameters were changed in the sensitivity analysis. Changing the resources for clinical surveillance did not affect the epidemic consequences. In conclusion, an FMD epidemic in Denmark would have a larger economic impact on the agricultural sector than previously anticipated. Furthermore, the control of a potential FMD outbreak in Denmark may be improved by combining pre-emptive depopulation with an enlarged protection or surveillance zone. PMID:26664996

  3. Endoplasmic reticulum stress responses differ in meninges and associated vasculature, striatum, and parietal cortex after a neurotoxic amphetamine exposure.

    PubMed

    Thomas, Monzy; George, Nysia I; Saini, Upasana T; Patterson, Tucker A; Hanig, Joseph P; Bowyer, John F

    2010-08-01

    Amphetamine (AMPH) is used to treat attention deficit and hyperactivity disorders, but it can produce neurotoxicity and adverse vascular effects at high doses. The endoplasmic reticulum (ER) stress response (ERSR) entails the unfolded protein response, which helps to avoid or minimize ER dysfunction. ERSR is often associated with toxicities resulting from the accumulation of unfolded or misfolded proteins and has been associated with methamphetamine toxicity in the striatum. The present study evaluates the effect of AMPH on several ERSR elements in meninges and associated vasculature (MAV), parietal cortex, and striatum. Adult, male Sprague-Dawley rats were exposed to saline, environmentally induced hyperthermia (EIH) or four consecutive doses of AMPH that produce hyperthermia. Expression changes (mRNA and protein levels) of key ERSR-related genes in MAV, striatum, and parietal cortex at 3 h or 1 day postdosing were monitored. AMPH increased the expression of some ERSR-related genes in all tissues. Atf4 (activating transcription factor 4, an indicator of Perk pathway activation), Hspa5/Grp78 (Glucose regulated protein 78, master regulator of ERSR), Pdia4 (protein disulfide isomerase, protein-folding enzyme), and Nfkb1 (nuclear factor of kappa b, ERSR sensor) mRNA increased significantly in MAV and parietal cortex 3 h after AMPH. In striatum, Atf4 and Hspa5/Grp78 mRNA significantly increased 3 h after AMPH, but Pdia4 and Nfkb11 did not. Thus, AMPH caused a robust activation of the Perk pathway in all tissues, but significant Ire1 pathway activation occurred only after AMPH treatment in the parietal cortex and striatum. Ddit3/Chop, a downstream effector of the ERSR pathway related to the neurotoxicity, was only increased in striatum and parietal cortex. Conversely, Pdia4, an enzyme protective in the ERSR, was only increased in MAV. The overall ERSR manifestation varied significantly between MAV, striatum, and parietal cortex after a neurotoxic exposure to AMPH.

  4. Aberrant Parietal Cortex Developmental Trajectories in Girls With Turner Syndrome and Related Visual–Spatial Cognitive Development: A Preliminary Study

    PubMed Central

    Green, Tamar; Chromik, Lindsay C.; Mazaika, Paul K.; Fierro, Kyle; Raman, Mira M.; Lazzeroni, Laura C.; Hong, David S.; Reiss, Allan L.

    2015-01-01

    Turner syndrome (TS) arises from partial or complete absence of the X-chromosome in females. Girls with TS show deficits in visual–spatial skills as well as reduced brain volume and surface area in the parietal cortex which supports these cognitive functions. Thus, measuring the developmental trajectory of the parietal cortex and the associated visual–spatial cognition in TS may provide novel insights into critical brain-behavior associations. In this longitudinal study, we acquired structural MRI data and assessed visual–spatial skills in 16 (age: 8.23 ±2.5) girls with TS and 13 age-matched controls over two time-points. Gray and white matter volume, surface area and cortical thickness were calculated from surfaced based segmentation of bilateral parietal cortices, and the NEPSY Arrows subtest was used to assess visual–spatial ability. Volumetric and cognitive scalars were modeled to obtain estimates of age-related change. The results show aberrant growth of white matter volume (P =0.011, corrected) and surface area (P =0.036, corrected) of the left superior parietal regions during childhood in girls with TS. Other parietal sub-regions were significantly smaller in girls with TS at both time-points but did not show different growth trajectories relative to controls. Furthermore, we found that visual–spatial skills showed a widening deficit for girls with TS relative to controls (P =0.003). Young girls with TS demonstrate an aberrant trajectory of parietal cortical and cognitive development during childhood. Elucidating aberrant neurodevelopmental trajectories in this population is critical for determining specific stages of brain maturation that are particularly dependent on TS-related genetic and hormonal factor. PMID:25044604

  5. Paroxysmal posterior variant alien hand syndrome associated with parietal lobe infarction: case presentation.

    PubMed

    Demiryürek, Bekir Enes; Gündogdu, Aslı Aksoy; Acar, Bilgehan Atılgan; Alagoz, Aybala Neslihan

    2016-10-01

    Alien hand syndrome (AHS) is an involuntary and rare neurological disorder emerges at upper extremity. AHS is a disconnection syndrome with the symptoms of losing sense of agency and sense of ownership, and presence of involuntary autonomic motor activity. There are frontal, callosal and posterior types of AHS and each of them occurs depend on the lesions of different of the brain. Posterior variant is a rarely encountered AHS type compared to others. AHS, generally regarded as persistent, but rarely maybe observed as paroxysmal. In this article, we present 71 year old patient with right posterior parietal lobe infarction and developed posterior variant AHS on left arm 1 month after discharge from the hospital. To discriminate AHS from conditions such as extrapyramidal movement disorders and epileptic seizures that take part in differential diagnosis should be kept in mind by the clinicians. Wrong and unnecessary treatments could be prevented in this way.

  6. Neuronal representation of saccadic error in macaque posterior parietal cortex (PPC).

    PubMed

    Zhou, Yang; Liu, Yining; Lu, Haidong; Wu, Si; Zhang, Mingsha

    2016-01-01

    Motor control, motor learning, self-recognition, and spatial perception all critically depend on the comparison of motor intention to the actually executed movement. Despite our knowledge that the brainstem-cerebellum plays an important role in motor error detection and motor learning, the involvement of neocortex remains largely unclear. Here, we report the neuronal computation and representation of saccadic error in macaque posterior parietal cortex (PPC). Neurons with persistent pre- and post-saccadic response (PPS) represent the intended end-position of saccade; neurons with late post-saccadic response (LPS) represent the actual end-position of saccade. Remarkably, after the arrival of the LPS signal, the PPS neurons' activity becomes highly correlated with the discrepancy between intended and actual end-position, and with the probability of making secondary (corrective) saccades. Thus, this neuronal computation might underlie the formation of saccadic error signals in PPC for speeding up saccadic learning and leading the occurrence of secondary saccade. PMID:27097103

  7. Temporary Interference over the Posterior Parietal Cortices Disrupts Thermoregulatory Control in Humans

    PubMed Central

    Gallace, Alberto; Soravia, Giovanna; Cattaneo, Zaira; Moseley, G. Lorimer; Vallar, Giuseppe

    2014-01-01

    The suggestion has recently been made that certain higher-order cortical areas involved in supporting multisensory representations of the body, and of the space around it, might also play a role in controlling thermoregulatory functions. Here we demonstrate that temporary interference with the function of one of these areas, the posterior parietal cortex, by repetitive transcranial magnetic stimulation, results in a decrease in limb temperature. By contrast, interference with the activity of a sensory-specific area (the primary somatosensory cortex) had no effect on temperature. The results of this experiment suggest that associative multisensory brain areas might exert a top-down modulation over basic physiological control. Such a function might be part of a larger neural circuit responsible for maintaining the integrity of the body at both a homeostatic and a psychological level. PMID:24622382

  8. Paroxysmal posterior variant alien hand syndrome associated with parietal lobe infarction: case presentation.

    PubMed

    Demiryürek, Bekir Enes; Gündogdu, Aslı Aksoy; Acar, Bilgehan Atılgan; Alagoz, Aybala Neslihan

    2016-10-01

    Alien hand syndrome (AHS) is an involuntary and rare neurological disorder emerges at upper extremity. AHS is a disconnection syndrome with the symptoms of losing sense of agency and sense of ownership, and presence of involuntary autonomic motor activity. There are frontal, callosal and posterior types of AHS and each of them occurs depend on the lesions of different of the brain. Posterior variant is a rarely encountered AHS type compared to others. AHS, generally regarded as persistent, but rarely maybe observed as paroxysmal. In this article, we present 71 year old patient with right posterior parietal lobe infarction and developed posterior variant AHS on left arm 1 month after discharge from the hospital. To discriminate AHS from conditions such as extrapyramidal movement disorders and epileptic seizures that take part in differential diagnosis should be kept in mind by the clinicians. Wrong and unnecessary treatments could be prevented in this way. PMID:27668023

  9. Functional definitions of parietal areas in human and non-human primates

    PubMed Central

    Orban, Guy A.

    2016-01-01

    Establishing homologies between cortical areas in animal models and humans lies at the heart of translational neuroscience, as it demonstrates how knowledge obtained from these models can be applied to the human brain. Here, we review progress in using parallel functional imaging to ascertain homologies between parietal areas of human and non-human primates, species sharing similar behavioural repertoires. The human homologues of several areas along monkey IPS involved in action planning and observation, such as AIP, LIP and CIP, as well as those of opercular areas (SII complex), have been defined. In addition, uniquely human areas, such as the tool-use area in left anterior supramarginal gyrus, have also been identified. PMID:27053755

  10. Broad domain generality in focal regions of frontal and parietal cortex

    PubMed Central

    Fedorenko, Evelina; Duncan, John; Kanwisher, Nancy

    2013-01-01

    Unlike brain regions that respond selectively to specific kinds of information content, a number of frontal and parietal regions are thought to be domain- and process-general: that is, active during a wide variety of demanding cognitive tasks. However, most previous evidence for this functional generality in humans comes from methods that overestimate activation overlap across tasks. Here we present functional MRI evidence from single-subject analyses for broad functional generality of a specific set of brain regions: the same sets of voxels are engaged across tasks ranging from arithmetic to storing information in working memory, to inhibiting irrelevant information. These regions have a specific topography, often lying directly adjacent to domain-specific regions. Thus, in addition to domain-specific brain regions tailored to solve particular problems of longstanding importance to our species, the human brain also contains a set of functionally general regions that plausibly endow us with the cognitive flexibility necessary to solve novel problems. PMID:24062451

  11. Parietal and bi-occipital lobe infarction confounded by ethanol-induced optic neuropathy.

    PubMed

    Tornatore, C W; Townsend, J C; Selvin, G J

    1991-08-01

    A frequent occurrence in geriatric and chronically ill patients is the exhibition of several simultaneously occurring and confounding health problems. This paper reports the case of a 61-year-old-white male who presented with an extensive history of multiple brain infarcts, hemiparesis, personality changes and varied visual complaints. Tests in the neurooptometric work-up for this patient included static automated perimetry, stereoacuity and optokinetic nystagmus evaluation. The results were suggestive of multiple cerebrovascular accidents which included the right and left occipital lobes as well as the right parietal lobe. This clinical picture was complicated by the presence of nutritional or ethanol-induced optic neuropathy. Emphasis was placed on a detailed sequential history of events and a complete neurological and optometric evaluation to ascertain the multiple foci of cortical infarction. Corroboration of clinical findings was obtained by computerized axial tomography (CT scan).

  12. Parietal and early visual cortices encode working memory content across mental transformations.

    PubMed

    Christophel, Thomas B; Cichy, Radoslaw M; Hebart, Martin N; Haynes, John-Dylan

    2015-02-01

    Active and flexible manipulations of memory contents "in the mind's eye" are believed to occur in a dedicated neural workspace, frequently referred to as visual working memory. Such a neural workspace should have two important properties: The ability to store sensory information across delay periods and the ability to flexibly transform sensory information. Here we used a combination of functional MRI and multivariate decoding to indentify such neural representations. Subjects were required to memorize a complex artificial pattern for an extended delay, then rotate the mental image as instructed by a cue and memorize this transformed pattern. We found that patterns of brain activity already in early visual areas and posterior parietal cortex encode not only the initially remembered image, but also the transformed contents after mental rotation. Our results thus suggest that the flexible and general neural workspace supporting visual working memory can be realized within posterior brain regions.

  13. Object vision to hand action in macaque parietal, premotor, and motor cortices

    PubMed Central

    Schaffelhofer, Stefan; Scherberger, Hansjörg

    2016-01-01

    Grasping requires translating object geometries into appropriate hand shapes. How the brain computes these transformations is currently unclear. We investigated three key areas of the macaque cortical grasping circuit with microelectrode arrays and found cooperative but anatomically separated visual and motor processes. The parietal area AIP operated primarily in a visual mode. Its neuronal population revealed a specialization for shape processing, even for abstract geometries, and processed object features ultimately important for grasping. Premotor area F5 acted as a hub that shared the visual coding of AIP only temporarily and switched to highly dominant motor signals towards movement planning and execution. We visualize these non-discrete premotor signals that drive the primary motor cortex M1 to reflect the movement of the grasping hand. Our results reveal visual and motor features encoded in the grasping circuit and their communication to achieve transformation for grasping. DOI: http://dx.doi.org/10.7554/eLife.15278.001 PMID:27458796

  14. Neurophysiology. Decoding motor imagery from the posterior parietal cortex of a tetraplegic human.

    PubMed

    Aflalo, Tyson; Kellis, Spencer; Klaes, Christian; Lee, Brian; Shi, Ying; Pejsa, Kelsie; Shanfield, Kathleen; Hayes-Jackson, Stephanie; Aisen, Mindy; Heck, Christi; Liu, Charles; Andersen, Richard A

    2015-05-22

    Nonhuman primate and human studies have suggested that populations of neurons in the posterior parietal cortex (PPC) may represent high-level aspects of action planning that can be used to control external devices as part of a brain-machine interface. However, there is no direct neuron-recording evidence that human PPC is involved in action planning, and the suitability of these signals for neuroprosthetic control has not been tested. We recorded neural population activity with arrays of microelectrodes implanted in the PPC of a tetraplegic subject. Motor imagery could be decoded from these neural populations, including imagined goals, trajectories, and types of movement. These findings indicate that the PPC of humans represents high-level, cognitive aspects of action and that the PPC can be a rich source for cognitive control signals for neural prosthetics that assist paralyzed patients.

  15. Early planning activity in frontal and parietal cortex in a simplified task

    PubMed Central

    Andersen, Richard A.

    2015-01-01

    Cortical planning activity has traditionally been probed with visual targets. However, external sensory signals might obscure early correlates of internally generated plans. We devised a nonspatial decision-making task in which the monkey is encouraged to decide randomly whether to reach or saccade in the absence of sensory stimuli. Neurons in frontal and parietal planning areas (in and around the arcuate and intraparietal sulci) showed responses predictive of the monkey's upcoming movement at early stages during the planning process. Neurons predicted the animal's future movements several seconds beforehand, sometimes before the trial even began. These data cast new light on the role of the cerebral cortex in the action planning process, when the animal is free to decide on his own actions in the absence of extraneous sensory cues. PMID:25761951

  16. Distinct Roles of the Prefrontal and Posterior Parietal Cortices in Response Inhibition.

    PubMed

    Zhou, Xin; Qi, Xue-Lian; Constantinidis, Christos

    2016-03-29

    The dorsolateral prefrontal cortex and posterior parietal cortex have been implicated in the planning of movements and inhibition of inappropriate responses, though their precise roles in these functions are not known. To address this question, we trained monkeys to perform memory-guided saccade and anti-saccade tasks and compared neural responses in the same animals. A population of neurons with no motor responses was also activated by a stimulus appearing out of the receptive field and could therefore mediate vector inversion. These neurons were found almost exclusively in the prefrontal cortex. Prefrontal cortical activity better predicted the level of performance in the task. Representation of the saccade goal also peaked in the prefrontal cortex at a time that was predictive of reaction time. These results suggest that the prefrontal cortex is the primary site of vector inversion in the cerebral cortex and explain the importance of this area in response inhibition. PMID:26997283

  17. Agnosia for mirror stimuli: a new case report with a small parietal lesion.

    PubMed

    Martinaud, Olivier; Mirlink, Nicolas; Bioux, Sandrine; Bliaux, Evangéline; Lebas, Axel; Gerardin, Emmanuel; Hannequin, Didier

    2014-11-01

    Only seven cases of agnosia for mirror stimuli have been reported, always with an extensive lesion. We report a new case of an agnosia for mirror stimuli due to a circumscribed lesion. An extensive battery of neuropsychological tests and a new experimental procedure to assess visual object mirror and orientation discrimination were assessed 10 days after the onset of clinical symptoms, and 5 years later. The performances of our patient were compared with those of four healthy control subjects matched for age. This test revealed an agnosia for mirror stimuli. Brain imaging showed a small right occipitoparietal hematoma, encompassing the extrastriate cortex adjoining the inferior parietal lobe. This new case suggests that: (i) agnosia for mirror stimuli can persist for 5 years after onset and (ii) the posterior part of the right intraparietal sulcus could be critical in the cognitive process of mirror stimuli discrimination.

  18. Bilateral parietal cortex damage does not impair associative memory for paired stimuli.

    PubMed

    Berryhill, Marian E; Drowos, David B; Olson, Ingrid R

    2009-10-01

    Recent neuroimaging and neuropsychological findings indicate that the posterior parietal cortex (PPC) plays an important, albeit undefined, role in episodic memory. Here we ask whether this region is specifically involved in associative aspects of episodic memory. Experiment 1 tested whether PPC damage affects the ability to learn and retrieve novel word pair associations. Experiment 2 tested whether PPC damage affects the retrieval of object-location associations, in a spatial fan task. In both experiments, patients showed normal levels of associative memory. These findings demonstrated that PPC damage did not prevent association memory for verbal items. Finally Experiment 3 tested whether PPC damage affects memory for nonverbal audio-visual pairs. The patients performed with normal accuracy, but with significantly reduced confidence. These findings indicate that the PPC does not have a central role in association formation per se and, instead, indicate that the PPC is involved in other aspects of episodic memory. PMID:20104378

  19. Dissociable parietal regions facilitate successful retrieval of recently learned and personally familiar information.

    PubMed

    Elman, Jeremy A; Cohn-Sheehy, Brendan I; Shimamura, Arthur P

    2013-03-01

    In fMRI analyses, the posterior parietal cortex (PPC) is particularly active during the successful retrieval of episodic memory. To delineate the neural correlates of episodic retrieval more succinctly, we compared retrieval of recently learned spatial locations (photographs of buildings) with retrieval of previously familiar locations (photographs of familiar campus buildings). Episodic retrieval of recently learned locations activated a circumscribed region within the ventral PPC (anterior angular gyrus and adjacent regions in the supramarginal gyrus) as well as medial PPC regions (posterior cingulated gyrus and posterior precuneus). Retrieval of familiar locations activated more posterior regions in the ventral PPC (posterior angular gyrus, LOC) and more anterior regions in the medial PPC (anterior precuneus and retrosplenial cortex). These dissociable effects define more precisely PPC regions involved in the retrieval of recent, contextually bound information as opposed to regions involved in other processes, such as visual imagery, scene reconstruction, and self-referential processing.

  20. Surface Reconstruction from Parallel Curves with Application to Parietal Bone Fracture Reconstruction

    PubMed Central

    Majeed, Abdul; Mt Piah, Abd Rahni; Ridzuan Yahya, Zainor

    2016-01-01

    Maxillofacial trauma are common, secondary to road traffic accident, sports injury, falls and require sophisticated radiological imaging to precisely diagnose. A direct surgical reconstruction is complex and require clinical expertise. Bio-modelling helps in reconstructing surface model from 2D contours. In this manuscript we have constructed the 3D surface using 2D Computerized Tomography (CT) scan contours. The fracture part of the cranial vault are reconstructed using GC1 rational cubic Ball curve with three free parameters, later the 2D contours are flipped into 3D with equidistant z component. The constructed surface is represented by contours blending interpolant. At the end of this manuscript a case report of parietal bone fracture is also illustrated by employing this method with a Graphical User Interface (GUI) illustration. PMID:26967643

  1. Bilateral Parietal Cortex Damage Does Not Impair Associative Memory for Paired Stimuli

    PubMed Central

    Berryhill, Marian E.; Drowos, David B.; Olson, Ingrid R.

    2010-01-01

    Recent neuroimaging and neuropsychological findings indicate that the posterior parietal cortex (PPC) plays an important, albeit undefined, role in episodic memory. Here we ask whether this region is specifically involved in associative aspects of episodic memory. Experiment 1 tested whether PPC damage affects the ability to learn and retrieve novel word-pair associations. Experiment 2 tested whether PPC damage affects the retrieval of object-location associations, in a spatial fan task. In both experiments, patients showed normal levels of associative memory. These findings demonstrated that PPC damage did not prevent association memory for verbal items. Finally Experiment 3 tested whether PPC damage affects memory for non-verbal audio-visual pairs. The patients performed with normal accuracy, but with significantly reduced confidence. These findings indicate that the PPC does not have a central role in association formation per se and instead, indicate that the PPC is involved in other aspects of episodic memory. PMID:20104378

  2. Task-specific versus generalized mnemonic representations in parietal and prefrontal cortices.

    PubMed

    Sarma, Arup; Masse, Nicolas Y; Wang, Xiao-Jing; Freedman, David J

    2016-01-01

    Our ability to learn a wide range of behavioral tasks is essential for responding appropriately to sensory stimuli according to behavioral demands, but the underlying neural mechanism has been rarely examined by neurophysiological recordings in the same subjects across learning. To understand how learning new behavioral tasks affects neuronal representations, we recorded from posterior parietal cortex (PPC) before and after training on a visual motion categorization task. We found that categorization training influenced cognitive encoding in PPC, with a marked enhancement of memory-related delay-period encoding during the categorization task that was absent during a motion discrimination task before categorization training. In contrast, the prefrontal cortex (PFC) exhibited strong delay-period encoding during both discrimination and categorization tasks. This reveals a dissociation between PFC's and PPC's roles in working memory, with general engagement of PFC across multiple tasks, in contrast with more task-specific mnemonic encoding in PPC. PMID:26595652

  3. [Signal transudation pathways in parietal cells of the gastric mucosa in experimental stomach ulcer].

    PubMed

    Ostapchenko, L I; Drobins'ka, O V; Chaĭka, V O; Bohun, L I; Bohdanova, O V; Kot, L I; Haĭda, L M

    2009-01-01

    The goal of the presented work was the research of signal transduction mechanism in the rat gastric parietal cells under stomach ulcer conditions. In these cells activation of adenylate cyclase (increase of cAMP level and proteinkinase A activity) and phosphoinositide (increases [Ca2+]i; cGMP and phoshatidylinocitole levels; proteinkinase C, proteinkinase G, and calmodulin-dependent-proteinkinase activity) of signals pathway was shown. An increase of plasma membrane phospholipids (PC, PS, PE, PI, LPC) level was shown. Under conditions of influence of the stress factor the membran enzymes activity (H+, K+ -ATPase, 5'-AMPase, Na+, K+ -ATPase, Ca2+, Mg2+ -ATPase and H+, K+ -ATPase) was considerably increased. The intensification of lipid peroxidation processes in rats was demonstrated.

  4. Object vision to hand action in macaque parietal, premotor, and motor cortices.

    PubMed

    Schaffelhofer, Stefan; Scherberger, Hansjörg

    2016-01-01

    Grasping requires translating object geometries into appropriate hand shapes. How the brain computes these transformations is currently unclear. We investigated three key areas of the macaque cortical grasping circuit with microelectrode arrays and found cooperative but anatomically separated visual and motor processes. The parietal area AIP operated primarily in a visual mode. Its neuronal population revealed a specialization for shape processing, even for abstract geometries, and processed object features ultimately important for grasping. Premotor area F5 acted as a hub that shared the visual coding of AIP only temporarily and switched to highly dominant motor signals towards movement planning and execution. We visualize these non-discrete premotor signals that drive the primary motor cortex M1 to reflect the movement of the grasping hand. Our results reveal visual and motor features encoded in the grasping circuit and their communication to achieve transformation for grasping. PMID:27458796

  5. Differential contribution of superior parietal and dorsal-lateral prefrontal cortices in copying.

    PubMed

    Averbeck, Bruno B; Crowe, David A; Chafee, Matthew V; Georgopoulos, Apostolos P

    2009-03-01

    In this study we examined the differential contribution of superior parietal cortex (SPC) and caudal dorsal-lateral prefrontal cortex (dlPFC) to drawing geometrical shapes. Monkeys were trained to draw triangles, squares, trapezoids and inverted triangles while we recorded the activity of small ensembles of neurons in caudal area 46 and areas 5 and 2 of parietal cortex. We analyzed the drawing factors encoded by individual neurons by fitting a step-wise general-linear model using as our dependent variable the firing rate averaged over segments of the produced trajectories. This analysis demonstrated that both cognitive (shape and segment serial position) and motor (maximum speed, position and direction of segment) factors modulated the activity of individual neurons. Furthermore, SPC had an enriched representation of both shape and motor factors, with the motor enrichment being stronger than the shape enrichment. Following this we used the activity in the simultaneously recorded neural ensembles to predict the hand velocity. In these analyses we found that the prediction of the hand velocity was better when we estimated different linear decoding functions for each shape than when we estimated a single function across shapes, although it was a subtle effect. Furthermore, we also found that ensembles of caudal dlPFC neurons carried considerable information about hand velocity, a purely motor factor. However, the SPC ensembles carried more information at the ensemble level as a function of the ensemble size than the caudal dlPFC ensembles, although the differences were not dramatic. Finally, an analysis of the response latencies of individual neurons showed that the caudal dlPFC representation was more sensory than the SPC representation, which was equally sensory and motor. Thus, this neurophysiological evidence suggests that both SPC and caudal dlPFC have a role in drawing, but that SPC plays a larger role in both the cognitive and the motor components.

  6. Training Transfers the Limits on Perception from Parietal to Ventral Cortex

    PubMed Central

    Chang, Dorita H.F.; Mevorach, Carmel; Kourtzi, Zoe; Welchman, Andrew E.

    2014-01-01

    Summary Visually guided behavior depends on (1) extracting and (2) discriminating signals from complex retinal inputs, and these perceptual skills improve with practice [1]. For instance, training on aerial reconnaissance facilitated World War II Allied military operations [2]; analysts pored over stereoscopic photographs, becoming expert at (1) segmenting pictures into meaningful items to break camouflage from (noisy) backgrounds, and (2) discriminating fine details to distinguish V-weapons from innocuous pylons. Training is understood to optimize neural circuits that process scene features (e.g., orientation) for particular purposes (e.g., judging position) [3–6]. Yet learning is most beneficial when it generalizes to other settings [7, 8] and is critical in recovery after adversity [9], challenging understanding of the circuitry involved. Here we used repetitive transcranial magnetic stimulation (rTMS) to infer the functional organization supporting learning generalization in the human brain. First, we show dissociable contributions of the posterior parietal cortex (PPC) versus lateral occipital (LO) circuits: extracting targets from noise is disrupted by PPC stimulation, in contrast to judging feature differences, which is affected by LO rTMS. Then, we demonstrate that training causes striking changes in this circuit: after feature training, identifying a target in noise is not disrupted by PPC stimulation but instead by LO stimulation. This indicates that training shifts the limits on perception from parietal to ventral brain regions and identifies a critical neural circuit for visual learning. We suggest that generalization is implemented by supplanting dynamic processing conducted in the PPC with specific feature templates stored in the ventral cortex. PMID:25283780

  7. Meta-analysis: how does posterior parietal cortex contribute to reasoning?

    PubMed Central

    Wendelken, Carter

    2015-01-01

    Reasoning depends on the contribution of posterior parietal cortex (PPC). But PPC is involved in many basic operations—including spatial attention, mathematical cognition, working memory, long-term memory, and language—and the nature of its contribution to reasoning is unclear. Psychological theories of the processes underlying reasoning make divergent claims about the neural systems that are likely to be involved, and better understanding the specific contribution of PPC can help to inform these theories. We set out to address several competing hypotheses, concerning the role of PPC in reasoning: (1) reasoning involves application of formal logic and is dependent on language, with PPC activation for reasoning mainly reflective of linguistic processing; (2) reasoning involves probabilistic computation and is thus dependent on numerical processing mechanisms in PPC; and (3) reasoning is built upon the representation and processing of spatial relations, and PPC activation associated with reasoning reflects spatial processing. We conducted two separate meta-analyses. First, we pooled data from our own studies of reasoning in adults, and examined activation in PPC regions of interest (ROI). Second, we conducted an automated meta-analysis using Neurosynth, in which we examined overlap between activation maps associated with reasoning and maps associated with other key functions of PPC. In both analyses, we observed reasoning-related activation concentrated in the left Inferior Parietal Lobe (IPL). Reasoning maps demonstrated the greatest overlap with mathematical cognition. Maintenance, visuospatial, and phonological processing also demonstrated some overlap with reasoning, but a large portion of the reasoning map did not overlap with the map for any other function. This evidence suggests that the PPC’s contribution to reasoning may be most closely related to its role in mathematical cognition, but that a core component of this contribution may be specific to

  8. Effects of Marijuana Use on Prefrontal and Parietal Volumes and Cognition in Emerging Adults

    PubMed Central

    Price, Jenessa S.; McQueeny, Tim; Shollenbarger, Skyler; Browning, Erin L.; Wieser, Jon; Lisdahl, Krista M.

    2015-01-01

    Rationale Chronic marijuana (MJ) use among adolescents has been associated with structural and functional abnormalities, particularly in developing regions responsible for higher order cognition. Objectives This study investigated prefrontal (PFC) and parietal volumes and executive function in emerging adult MJ users and explored potential gender differences. Methods Participants (ages 18–25) were 27 MJ users and 32 controls without neurologic or psychiatric disorders or heavy other drug use. A series of multiple regressions examined whether group status, past year MJ use, and their interactions with gender predicted ROI volumes. Post-hoc analyses consisted of brain-behavior correlations between volumes and cognitive variables and Fisher’s z tests to assess group differences. Results MJ users demonstrated significantly smaller medial orbitofrontal (mOFC; p=.004, FDR p=.024) and inferior parietal volumes (p=.04, FDR p=.12); follow-up regressions found that increased past year MJ use did not significantly dose-dependently predict smaller mOFC volume in a sub-sample of individuals with at least one past year MJ use. There were no significant gender interactions. There was a significant brain-behavior difference by group, such that smaller mOFC volumes were associated with poorer complex attention for MJ users (p<.05). Conclusions Smaller mOFC volumes among MJ users suggest disruption of typical neurodevelopmental processes associated with regular MJ use for both genders. These results highlight the need for longitudinal, multi-modal imaging studies providing clearer information on timing of neurodevelopmental processes and neurocognitive impacts of youth MJ initiation. PMID:25921032

  9. The capacity constraint in the prefrontal and parietal regions for coordinating dual arithmetic tasks.

    PubMed

    Kuo, Bo-Cheng; Yeh, Yei-Yu; Chen, Der-Yow; Liang, Keng Chen; Chen, Jyh-Horng

    2008-03-14

    Using a dual-serial-arithmetic paradigm, we examined whether a capacity limitation constrains the neural activation that underlies dual-task performance. Six conditions were run in the experiment (the baseline, single-addition, single-subtraction, dual-addition, dual-subtraction, and the dual-operation condition). In the baseline condition, participants were asked to remember the initial pair of numbers and ignore subsequent stimuli. In the single-addition and single-subtraction conditions, participants had to calculate a running total over a series of stimuli. In the dual-addition and dual-subtraction conditions, they had to do two arithmetic tasks involving the same operand (e.g., + 2 and + 7, - 3 and - 5). Participants performed one addition and one subtraction task (e.g., + 2 and - 7, - 3 and + 5) in the dual-operation condition. The functional magnetic resonance imaging results showed strict left prefrontal and parietal regions in the single-addition condition and bilateral activation in the single-subtraction condition. Greater activation in the prefrontal and parietal regions was observed in both the dual-operation condition and the dual-addition condition in comparison to the single-addition condition. No greater activation was observed in either the dual-operation condition or dual-subtraction condition in comparison to the single-subtraction condition. These results suggest a constraint imposed by a limit in capacity for the neural activity subserving dual-task performance when one of the tasks places high resource demands on the executive network.

  10. Causal interactions between fronto-parietal central executive and default-mode networks in humans

    PubMed Central

    Chen, Ashley C.; Oathes, Desmond J.; Chang, Catie; Bradley, Travis; Zhou, Zheng-Wei; Williams, Leanne M.; Glover, Gary H.; Deisseroth, Karl; Etkin, Amit

    2013-01-01

    Information processing during human cognitive and emotional operations is thought to involve the dynamic interplay of several large-scale neural networks, including the fronto-parietal central executive network (CEN), cingulo-opercular salience network (SN), and the medial prefrontal-medial parietal default mode networks (DMN). It has been theorized that there is a causal neural mechanism by which the CEN/SN negatively regulate the DMN. Support for this idea has come from correlational neuroimaging studies; however, direct evidence for this neural mechanism is lacking. Here we undertook a direct test of this mechanism by combining transcranial magnetic stimulation (TMS) with functional MRI to causally excite or inhibit TMS-accessible prefrontal nodes within the CEN or SN and determine consequent effects on the DMN. Single-pulse excitatory stimulations delivered to only the CEN node induced negative DMN connectivity with the CEN and SN, consistent with the CEN/SN’s hypothesized negative regulation of the DMN. Conversely, low-frequency inhibitory repetitive TMS to the CEN node resulted in a shift of DMN signal from its normally low-frequency range to a higher frequency, suggesting disinhibition of DMN activity. Moreover, the CEN node exhibited this causal regulatory relationship primarily with the medial prefrontal portion of the DMN. These findings significantly advance our understanding of the causal mechanisms by which major brain networks normally coordinate information processing. Given that poorly regulated information processing is a hallmark of most neuropsychiatric disorders, these findings provide a foundation for ways to study network dysregulation and develop brain stimulation treatments for these disorders. PMID:24248372

  11. Functional Connectivity Between Superior Parietal Lobule and Primary Visual Cortex "at Rest" Predicts Visual Search Efficiency.

    PubMed

    Bueichekú, Elisenda; Ventura-Campos, Noelia; Palomar-García, María-Ángeles; Miró-Padilla, Anna; Parcet, María-Antonia; Ávila, César

    2015-10-01

    Spatiotemporal activity that emerges spontaneously "at rest" has been proposed to reflect individual a priori biases in cognitive processing. This research focused on testing neurocognitive models of visual attention by studying the functional connectivity (FC) of the superior parietal lobule (SPL), given its central role in establishing priority maps during visual search tasks. Twenty-three human participants completed a functional magnetic resonance imaging session that featured a resting-state scan, followed by a visual search task based on the alphanumeric category effect. As expected, the behavioral results showed longer reaction times and more errors for the within-category (i.e., searching a target letter among letters) than the between-category search (i.e., searching a target letter among numbers). The within-category condition was related to greater activation of the superior and inferior parietal lobules, occipital cortex, inferior frontal cortex, dorsal anterior cingulate cortex, and the superior colliculus than the between-category search. The resting-state FC analysis of the SPL revealed a broad network that included connections with the inferotemporal cortex, dorsolateral prefrontal cortex, and dorsal frontal areas like the supplementary motor area and frontal eye field. Noteworthy, the regression analysis revealed that the more efficient participants in the visual search showed stronger FC between the SPL and areas of primary visual cortex (V1) related to the search task. We shed some light on how the SPL establishes a priority map of the environment during visual attention tasks and how FC is a valuable tool for assessing individual differences while performing cognitive tasks. PMID:26230367

  12. Decreased limbic and increased fronto-parietal connectivity in unmedicated patients with obsessive-compulsive disorder.

    PubMed

    Göttlich, Martin; Krämer, Ulrike M; Kordon, Andreas; Hohagen, Fritz; Zurowski, Bartosz

    2014-11-01

    Obsessive-compulsive disorder (OCD) is characterized by recurrent intrusive thoughts and ritualized, repetitive behaviors, or mental acts. Convergent experimental evidence from neuroimaging and neuropsychological studies supports an orbitofronto-striato-thalamo-cortical dysfunction in OCD. Moreover, an over excitability of the amygdala and over monitoring of thoughts and actions involving the anterior cingulate, frontal and parietal cortex has been proposed as aspects of pathophysiology in OCD. We chose a data driven, graph theoretical approach to investigate brain network organization in 17 unmedicated OCD patients and 19 controls using resting-state fMRI. OCD patients showed a decreased connectivity of the limbic network to several other brain networks: the basal ganglia network, the default mode network, and the executive/attention network. The connectivity within the limbic network was also found to be decreased in OCD patients compared to healthy controls. Furthermore, we found a stronger connectivity of brain regions within the executive/attention network in OCD patients. This effect was positively correlated with disease severity. The decreased connectivity of limbic regions (amygdala, hippocampus) may be related to several neurocognitive deficits observed in OCD patients involving implicit learning, emotion processing and expectation, and processing of reward and punishment. Limbic disconnection from fronto-parietal regions relevant for (re)-appraisal may explain why intrusive thoughts become and/or remain threatening to patients but not to healthy subjects. Hyperconnectivity within the executive/attention network might be related to OCD symptoms such as excessive monitoring of thoughts and behavior as a dysfunctional strategy to cope with threat and uncertainty. PMID:25044747

  13. Evolution of mammalian sensorimotor cortex: thalamic projections to parietal cortical areas in Monodelphis domestica

    PubMed Central

    Dooley, James C.; Franca, João G.; Seelke, Adele M. H.; Cooke, Dylan F.; Krubitzer, Leah A.

    2015-01-01

    The current experiments build upon previous studies designed to reveal the network of parietal cortical areas present in the common mammalian ancestor. Understanding this ancestral network is essential for highlighting the basic somatosensory circuitry present in all mammals, and how this basic plan was modified to generate species specific behaviors. Our animal model, the short-tailed opossum (Monodelphis domestica), is a South American marsupial that has been proposed to have a similar ecological niche and morphology to the earliest common mammalian ancestor. In this investigation, we injected retrograde neuroanatomical tracers into the face and body representations of primary somatosensory cortex (S1), the rostral and caudal somatosensory fields (SR and SC), as well as a multimodal region (MM). Projections from different architectonically defined thalamic nuclei were then quantified. Our results provide further evidence to support the hypothesized basic mammalian plan of thalamic projections to S1, with the lateral and medial ventral posterior thalamic nuclei (VPl and VPm) projecting to S1 body and S1 face, respectively. Additional strong projections are from the medial division of posterior nucleus (Pom). SR receives projections from several midline nuclei, including the medial dorsal, ventral medial nucleus, and Pom. SC and MM show similar patterns of connectivity, with projections from the ventral anterior and ventral lateral nuclei, VPm and VPl, and the entire posterior nucleus (medial and lateral). Notably, MM is distinguished from SC by relatively dense projections from the dorsal division of the lateral geniculate nucleus and pulvinar. We discuss the finding that S1 of the short-tailed opossum has a similar pattern of projections as other marsupials and mammals, but also some distinct projections not present in other mammals. Further we provide additional support for a primitive posterior parietal cortex which receives input from multiple modalities. PMID

  14. Spatial and Temporal Eye–Hand Coordination Relies on the Parietal Reach Region

    PubMed Central

    Hauschild, Markus; Wilke, Melanie; Andersen, Richard A.

    2014-01-01

    Coordinated eye movements are crucial for precision control of our hands. A commonly believed neural mechanism underlying eye–hand coordination is interaction between the neural networks controlling each effector, exchanging, and matching information, such as movement target location and onset time. Alternatively, eye–hand coordination may result simply from common inputs to independent eye and hand control pathways. Thus far, it remains unknown whether and where either of these two possible mechanisms exists. A candidate location for the former mechanism, interpathway communication, includes the posterior parietal cortex (PPC) where distinct effector-specific areas reside. If the PPC were within the network for eye–hand coordination, perturbing it would affect both eye and hand movements that are concurrently planned. In contrast, if eye–hand coordination arises solely from common inputs, perturbing one effector pathway, e.g., the parietal reach region (PRR), would not affect the other effector. To test these hypotheses, we inactivated part of PRR in the macaque, located in the medial bank of the intraparietal sulcus encompassing the medial intraparietal area and area 5V. When each effector moved alone, PRR inactivation shortened reach but not saccade amplitudes, compatible with the known reach-selective activity of PRR. However, when both effectors moved concurrently, PRR inactivation shortened both reach and saccade amplitudes, and decoupled their reaction times. Therefore, consistent with the interpathway communication hypothesis, we propose that the planning of concurrent eye and hand movements causes the spatial information in PRR to influence the otherwise independent eye control pathways, and that their temporal coupling requires an intact PRR. PMID:25232123

  15. Electrocorticography reveals the temporal dynamics of posterior parietal cortical activity during recognition memory decisions.

    PubMed

    Gonzalez, Alex; Hutchinson, J Benjamin; Uncapher, Melina R; Chen, Janice; LaRocque, Karen F; Foster, Brett L; Rangarajan, Vinitha; Parvizi, Josef; Wagner, Anthony D

    2015-09-01

    Theories of the neurobiology of episodic memory predominantly focus on the contributions of medial temporal lobe structures, based on extensive lesion, electrophysiological, and imaging evidence. Against this backdrop, functional neuroimaging data have unexpectedly implicated left posterior parietal cortex (PPC) in episodic retrieval, revealing distinct activation patterns in PPC subregions as humans make memory-related decisions. To date, theorizing about the functional contributions of PPC has been hampered by the absence of information about the temporal dynamics of PPC activity as retrieval unfolds. Here, we leveraged electrocorticography to examine the temporal profile of high gamma power (HGP) in dorsal PPC subregions as participants made old/new recognition memory decisions. A double dissociation in memory-related HGP was observed, with activity in left intraparietal sulcus (IPS) and left superior parietal lobule (SPL) differing in time and sign for recognized old items (Hits) and correctly rejected novel items (CRs). Specifically, HGP in left IPS increased for Hits 300-700 ms poststimulus onset, and decayed to baseline ∼200 ms preresponse. By contrast, HGP in left SPL increased for CRs early after stimulus onset (200-300 ms) and late in the memory decision (from 700 ms to response). These memory-related effects were unique to left PPC, as they were not observed in right PPC. Finally, memory-related HGP in left IPS and SPL was sufficiently reliable to enable brain-based decoding of the participant's memory state at the single-trial level, using multivariate pattern classification. Collectively, these data provide insights into left PPC temporal dynamics as humans make recognition memory decisions. PMID:26283375

  16. The contribution of fronto-parietal regions to sentence comprehension: insights from the Moses illusion.

    PubMed

    Raposo, Ana; Marques, J Frederico

    2013-12-01

    To interpret a sentence, the reader must not only process the linguistic input, but many times has also to draw inferences about what is implicitly stated. In some cases, the generation and integration of inferred information may lead to semantic illusions. In these sentences, subjects fail to detect errors such as in "It was two animals of each kind that Moses took on the ark" despite knowing that the correct answer is Noah, not Moses. The relative inability to notice these errors raises questions about how people establish and integrate inferences and which conditions improve error detection. To unravel the neural processes underlying inference and error detection in language comprehension, we carried out an fMRI study in which participants read sentences containing true or false statements. The false statements either took the form of more obvious (i.e., clearly false) or subtle (i.e., semantic illusions) inconsistent relations. Participants had to decide if each statement was true or false. Processing semantic illusions relative to true and clearly false sentences significantly engaged the right inferior parietal lobule, suggesting higher demands in establishing coherence. Successful versus unsuccessful error detection revealed a network of regions, including right dorsolateral prefrontal cortex, orbitofrontal, insula/putamen and anterior cingulate cortex. Such activation was significantly correlated with overall response accuracy to the illusions. These results suggest that to detect the semantic conflict, people must inhibit the tendency to draw pragmatic inferences. These findings demonstrate that fronto-parietal areas are involved in inference and inhibition processes necessary for establishing semantic coherence.

  17. Computer modeling of gastric parietal cell: significance of canalicular space, gland lumen, and variable canalicular [K+].

    PubMed

    Crothers, James M; Forte, John G; Machen, Terry E

    2016-05-01

    A computer model, constructed for evaluation of integrated functioning of cellular components involved in acid secretion by the gastric parietal cell, has provided new interpretations of older experimental evidence, showing the functional significance of a canalicular space separated from a mucosal bath by a gland lumen and also shedding light on basolateral Cl(-) transport. The model shows 1) changes in levels of parietal cell secretion (with stimulation or H-K-ATPase inhibitors) result mainly from changes in electrochemical driving forces for apical K(+) and Cl(-) efflux, as canalicular [K(+)] ([K(+)]can) increases or decreases with changes in apical H(+)/K(+) exchange rate; 2) H-K-ATPase inhibition in frog gastric mucosa would increase [K(+)]can similarly with low or high mucosal [K(+)], depolarizing apical membrane voltage similarly, so electrogenic H(+) pumping is not indicated by inhibition causing similar increase in transepithelial potential difference (Vt) with 4 and 80 mM mucosal K(+); 3) decreased H(+) secretion during strongly mucosal-positive voltage clamping is consistent with an electroneutral H-K-ATPase being inhibited by greatly decreased [K(+)]can (Michaelis-Menten mechanism); 4) slow initial change ("long time-constant transient") in current or Vt with clamping of Vt or current involves slow change in [K(+)]can; 5) the Na(+)-K(+)-2Cl(-) symporter (NKCC) is likely to have a significant role in Cl(-) influx, despite evidence that it is not necessary for acid secretion; and 6) relative contributions of Cl(-)/HCO3 (-) exchanger (AE2) and NKCC to Cl(-) influx would differ greatly between resting and stimulated states, possibly explaining reported differences in physiological characteristics of stimulated open-circuit Cl(-) secretion (≈H(+)) and resting short-circuit Cl(-) secretion (>H(+)).

  18. Prefrontal, posterior parietal and sensorimotor network activity underlying speed control during walking

    PubMed Central

    Bulea, Thomas C.; Kim, Jonghyun; Damiano, Diane L.; Stanley, Christopher J.; Park, Hyung-Soon

    2015-01-01

    Accumulating evidence suggests cortical circuits may contribute to control of human locomotion. Here, noninvasive electroencephalography (EEG) recorded from able-bodied volunteers during a novel treadmill walking paradigm was used to assess neural correlates of walking. A systematic processing method, including a recently developed subspace reconstruction algorithm, reduced movement-related EEG artifact prior to independent component analysis and dipole source localization. We quantified cortical activity while participants tracked slow and fast target speeds across two treadmill conditions: an active mode that adjusted belt speed based on user movements and a passive mode reflecting a typical treadmill. Our results reveal frequency specific, multi-focal task related changes in cortical oscillations elicited by active walking. Low γ band power, localized to the prefrontal and posterior parietal cortices, was significantly increased during double support and early swing phases, critical points in the gait cycle since the active controller adjusted speed based on pelvis position and swing foot velocity. These phasic γ band synchronizations provide evidence that prefrontal and posterior parietal networks, previously implicated in visuo-spatial and somotosensory integration, are engaged to enhance lower limb control during gait. Sustained μ and β band desynchronization within sensorimotor cortex, a neural correlate for movement, was observed during walking thereby validating our methods for isolating cortical activity. Our results also demonstrate the utility of EEG recorded during locomotion for probing the multi-regional cortical networks which underpin its execution. For example, the cortical network engagement elicited by the active treadmill suggests that it may enhance neuroplasticity for more effective motor training. PMID:26029077

  19. Decreased limbic and increased fronto-parietal connectivity in unmedicated patients with obsessive-compulsive disorder.

    PubMed

    Göttlich, Martin; Krämer, Ulrike M; Kordon, Andreas; Hohagen, Fritz; Zurowski, Bartosz

    2014-11-01

    Obsessive-compulsive disorder (OCD) is characterized by recurrent intrusive thoughts and ritualized, repetitive behaviors, or mental acts. Convergent experimental evidence from neuroimaging and neuropsychological studies supports an orbitofronto-striato-thalamo-cortical dysfunction in OCD. Moreover, an over excitability of the amygdala and over monitoring of thoughts and actions involving the anterior cingulate, frontal and parietal cortex has been proposed as aspects of pathophysiology in OCD. We chose a data driven, graph theoretical approach to investigate brain network organization in 17 unmedicated OCD patients and 19 controls using resting-state fMRI. OCD patients showed a decreased connectivity of the limbic network to several other brain networks: the basal ganglia network, the default mode network, and the executive/attention network. The connectivity within the limbic network was also found to be decreased in OCD patients compared to healthy controls. Furthermore, we found a stronger connectivity of brain regions within the executive/attention network in OCD patients. This effect was positively correlated with disease severity. The decreased connectivity of limbic regions (amygdala, hippocampus) may be related to several neurocognitive deficits observed in OCD patients involving implicit learning, emotion processing and expectation, and processing of reward and punishment. Limbic disconnection from fronto-parietal regions relevant for (re)-appraisal may explain why intrusive thoughts become and/or remain threatening to patients but not to healthy subjects. Hyperconnectivity within the executive/attention network might be related to OCD symptoms such as excessive monitoring of thoughts and behavior as a dysfunctional strategy to cope with threat and uncertainty.

  20. Distinct contribution of the parietal and temporal cortex to hand configuration and contextual judgements about tools.

    PubMed

    Andres, Michael; Pelgrims, Barbara; Olivier, Etienne

    2013-09-01

    Neuropsychological studies showed that manipulatory and semantic knowledge can be independently impaired in patients with upper-limb apraxia, leading to different tool use disorders. The present study aimed to dissociate the brain regions involved in judging the hand configuration or the context associated to tool use. We focussed on the left supramarginalis gyrus (SMG) and left middle temporal gyrus (MTG), whose activation, as evidenced by functional magnetic resonance imaging (fMRI) studies, suggests that they may play a critical role in tool use. The distinctive location of SMG in the dorsal visual stream led us to postulate that this parietal region could play a role in processing incoming information about tools to shape hand posture. In contrast, we hypothesized that MTG, because of its interconnections with several cortical areas involved in semantic memory, could contribute to retrieving semantic information necessary to create a contextual representation of tool use. To test these hypotheses, we used neuronavigated transcranial magnetic stimulation (TMS) to interfere transiently with the function of either left SMG or left MTG in healthy participants performing judgement tasks about either hand configuration or context of tool use. We found that SMG virtual lesions impaired hand configuration but not contextual judgements, whereas MTG lesions selectively interfered with judgements about the context of tool use while leaving hand configuration judgements unaffected. This double dissociation demonstrates that the ability to infer a context of use or a hand posture from tool perception relies on distinct processes, performed in the temporal and parietal regions. The present findings suggest that tool use disorders caused by SMG lesions will be characterized by difficulties in selecting the appropriate hand posture for tool use, whereas MTG lesions will yield difficulties in using tools in the appropriate context.

  1. Functional Connectivity Between Superior Parietal Lobule and Primary Visual Cortex "at Rest" Predicts Visual Search Efficiency.

    PubMed

    Bueichekú, Elisenda; Ventura-Campos, Noelia; Palomar-García, María-Ángeles; Miró-Padilla, Anna; Parcet, María-Antonia; Ávila, César

    2015-10-01

    Spatiotemporal activity that emerges spontaneously "at rest" has been proposed to reflect individual a priori biases in cognitive processing. This research focused on testing neurocognitive models of visual attention by studying the functional connectivity (FC) of the superior parietal lobule (SPL), given its central role in establishing priority maps during visual search tasks. Twenty-three human participants completed a functional magnetic resonance imaging session that featured a resting-state scan, followed by a visual search task based on the alphanumeric category effect. As expected, the behavioral results showed longer reaction times and more errors for the within-category (i.e., searching a target letter among letters) than the between-category search (i.e., searching a target letter among numbers). The within-category condition was related to greater activation of the superior and inferior parietal lobules, occipital cortex, inferior frontal cortex, dorsal anterior cingulate cortex, and the superior colliculus than the between-category search. The resting-state FC analysis of the SPL revealed a broad network that included connections with the inferotemporal cortex, dorsolateral prefrontal cortex, and dorsal frontal areas like the supplementary motor area and frontal eye field. Noteworthy, the regression analysis revealed that the more efficient participants in the visual search showed stronger FC between the SPL and areas of primary visual cortex (V1) related to the search task. We shed some light on how the SPL establishes a priority map of the environment during visual attention tasks and how FC is a valuable tool for assessing individual differences while performing cognitive tasks.

  2. Long term follow up of idiopathic gingival enlargement associated with chronic periodontitis: A case report and review

    PubMed Central

    Nagarale, Girish P.; Ravindra, S.; Thakur, Srinath; Setty, Swati

    2013-01-01

    Background: Idiopathic gingival enlargement is a rare condition characterized by massive enlargement of the gingiva. It may be associated with other diseases/conditions characterizing a syndrome, but rarely associated with periodontitis. Case Description: This case report describes an unusual clinical form of gingival enlargement associated with chronic periodontitis. Clinical examination revealed diffuse gingival enlargement. The lesion was asymptomatic, firm, and pinkish red. Generalized periodontal pockets were observed. Radiographic evaluation revealed generalized severe alveolar bone loss. Histopathological investigations revealed atrophic epithelium with dense fibrocollagenous tissue. Lesions healed successfully following extraction and surgical excision, and no recurrence was observed after 1 year follow-up but recurrence was observed at 3 and 5-years follow-up. Clinical Implications: Successful treatment of idiopathic gingival enlargement depends on proper identification of etiologic factors and improving esthetics and function through surgical excision of the over growth. However, there may be recurrence. PMID:23869135

  3. Enlarged FAMSBASE: protein 3D structure models of genome sequences for 41 species

    PubMed Central

    Yamaguchi, Akihiro; Iwadate, Mitsuo; Suzuki, Ei-ichiro; Yura, Kei; Kawakita, Shigetsugu; Umeyama, Hideaki; Go, Mitiko

    2003-01-01

    Enlarged FAMSBASE is a relational database of comparative protein structure models for the whole genome of 41 species, presented in the GTOP database. The models are calculated by Full Automatic Modeling System (FAMS). Enlarged FAMSBASE provides a wide range of query keys, such as name of ORF (open reading frame), ORF keywords, Protein Data Bank (PDB) ID, PDB heterogen atoms and sequence similarity. Heterogen atoms in PDB include cofactors, ligands and other factors that interact with proteins, and are a good starting point for analyzing interactions between proteins and other molecules. The data may also work as a template for drug design. The present number of ORFs with protein 3D models in FAMSBASE is 183 805, and the database includes an average of three models for each ORF. FAMSBASE is available at http://famsbase.bio.nagoya-u.ac.jp/famsbase/. PMID:12520053

  4. Soybean cell enlargement oscillates with a temperature-compensated period length of ca. 24 min

    NASA Technical Reports Server (NTRS)

    Morre, D. J.; Pogue, R.; Morre, D. M.

    2001-01-01

    Rate of enlargement of epidermal cells from soybean, when measured at intervals of 1 min using a light microscope equipped with a video measurement system, oscillated with a period length of about 24 min. This oscillation parallels the 24-min periodicity observed for the oxidation of NADH by the external plasma membrane NADH oxidase. The increase in length was not only non-linear, but intervals of rapid increase in area alternated with intervals of rapid decrease in area. The length of the period was temperature compensated, and was approximately the same when measured at 14, 24 and 34 degrees C even though the rate of cell enlargement varied over this same range of temperatures. These observations represent the first demonstration of an oscillatory growth behavior correlated with a biochemical activity where the period length of both is independent of temperature (temperature compensated) as is the hallmark of clock-related biological phenomena.

  5. Pollen tube contents initiate ovule enlargement and enhance seed coat development without fertilization

    PubMed Central

    Kasahara, Ryushiro D.; Notaguchi, Michitaka; Nagahara, Shiori; Suzuki, Takamasa; Susaki, Daichi; Honma, Yujiro; Maruyama, Daisuke; Higashiyama, Tetsuya

    2016-01-01

    In angiosperms, pollen tubes carry two sperm cells toward the egg and central cells to complete double fertilization. In animals, not only sperm but also seminal plasma is required for proper fertilization. However, little is known regarding the function of pollen tube content (PTC), which is analogous to seminal plasma. We report that the PTC plays a vital role in the prefertilization state and causes an enlargement of ovules without fertilization. We termed this phenomenon as pollen tube–dependent ovule enlargement morphology and placed it between pollen tube guidance and double fertilization. Additionally, PTC increases endosperm nuclei without fertilization when combined with autonomous endosperm mutants. This finding could be applied in agriculture, particularly in enhancing seed formation without fertilization in important crops.

  6. Enlargement of mitral valve ring in a young woman with severe prosthesis-patient mismatch.

    PubMed

    Attisani, Matteo; Pellegrini, Augusto; Sorrentino, Paolo; Rinaldi, Mauro

    2014-04-01

    Mechanical prosthesis is the first choice for valve replacement at the mitral position in children. Replacement of the original prosthesis because of prosthesis-patient mismatch (PPM) is almost inevitable when prostheses are implanted in small children. The impact of PPM on long-term mortality becomes significant when the effective orifice area (EOA) is severely reduced. In these cases prosthesis replacement can be technically difficult, and it often requires extended enlargement of the mitral valve annulus ring. We report a case of a woman who underwent a mitral valve replacement with a 19-mm St. Jude mechanical prosthetic valve at the age of 3 years. At the age of 33 years, the patient underwent a successful minimally invasive mitral annulus ring enlargement and implantation of a 23-mm St. Jude mechanical prosthetic valve via a right minithoracotomy. PMID:24808442

  7. Foveated scanning: dynamic monodimensional enlargement of resolved field of view in lenses of scanner systems.

    PubMed

    Javaherian, Farhang; Rashidian, Bizhan

    2016-09-10

    An inconsistency between the circular symmetric geometry of conventional optical imagers and the geometry of long linear sensors used in today's line-scan cameras results in suboptimal separate design of optics and electronics of scanner systems. Based on the method of foveated optical imaging, a technique named foveated scanning (FS) is proposed in this paper. The FS technique is employed to enlarge the one-dimensional resolved field of view (RFOV) of conventional lenses and permits optimized performance on a line-of-interest in the image plane where the optoelectronic sensor is located. The achieved enlargement of RFOV is verified on a proof-of-concept basic telephoto lens. Both modulation transfer function analysis and the imaging simulation of a standard target have been performed. Results show a twofold increase in RFOV by this technique. PMID:27661368

  8. Ectopic opening of cystic dilatation of the ejaculatory duct into enlarged prostatic utricle.

    PubMed

    Lin, Jian-Zhong; Wu, Hong-Fei; Wang, Ji-Chen; Le, Mei-Zhao; Yu, Hong-Bo; Zhou, He-Tong

    2012-01-01

    A 28-year-old man was referred to our department for the management of recurrent hemospermia during the past 5 years. Genital examination and hormonal levels were normal. Semen analysis showed no change in volume and pH; however, hemospermia and asthenozoospermia were observed. Ultrasonography and computed tomography scan revealed the presence of a cystic lesion with calcification in the terminal part of seminal vesicles adjoining the prostate gland. The following vasography and endoscopic retrograde urethrography demonstrated 2 communicating cystic dilatations arising from the verumontanum. The diagnosis of cystic dilatation of the ejaculatory duct opening into an enlarged prostatic utricle was reached. Transurethral unroofing of the cyst was separately performed with a successful outcome. The characteristic of the 2 cystic dilatations was confirmed by pathologic examination. To the best of our knowledge, this is the first case of ectopic cystic dilatation of the ejaculatory duct opening into an enlarged prostatic utricle.

  9. Impact of the European Union enlargement on health professionals and health care systems.

    PubMed

    Avgerinos, Efthimios D; Koupidis, Sotirios A; Filippou, Dimitrios K

    2004-09-01

    As the European family enlarges, the admission of new human resources in the health services will have an impact on the European market and health care system. Under the umbrella of the European Union (EU) equality, the educational quality barriers (e.g. PLAB test in UK, DIKATSA test in Greece) will be abolished. The overproduction of health professionals and their heterogeneous regional and per specialty distribution will lead to medical unemployment and demotion of the medical profession. Medical and political authorities and decision makers of the EU need to reform the European Health System, supervise, and assess the quality of medical education, harmonize the individual National Health System policies, and follow the World Health Organization (regional office for Europe) guidelines on health policy. An agreed, structured European Health Policy might moderate the vibrations of the forthcoming EU enlargement.

  10. 18. (4"X5" image enlarged from 2 1/4" negative) Sam Fowler, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. (4"X5" image enlarged from 2 1/4" negative) Sam Fowler, Photographer, February 1998 VIEW OF GEORGIA DOT BRIDGE NO. 051-00025D-01986N (JAMES P. HOULIHAN BRIDGE) APPROACH SPAN FENDER. DOLPHIN LOCATED AT RIGHT. NAVIGATIONAL LIGHT LOCATED ON TOP OF FENDER - Georgia DOT Bridge No. 051-00025D-01986N, US 17 & State Route 25 Spanning Savannah River, Port Wentworth, Chatham County, GA

  11. Subjective assessment of right ventricle enlargement from computed tomography pulmonary angiography images.

    PubMed

    Kumamaru, Kanako K; Hunsaker, Andetta R; Bedayat, Arash; Soga, Shigeyoshi; Signorelli, Jason; Adams, Kimberly; Wake, Nicole; Lu, Michael T; Rybicki, Frank J

    2012-04-01

    To retrospectively evaluate prognostic accuracy of subjective assessment of right ventricle (RV) enlargement on CT pulmonary angiography (CTPA) images in comparison with objective measures of RV enlargement in patients with acute pulmonary embolism (PE). For 200 consecutive patients with acute PE, two readers blinded to patient outcomes subjectively determined whether the maximum RV diameter was greater than that of the left ventricle (LV) using axial CTPA images. For the objective measurements, RV/LV diameter ratios were calculated using axial images and 4-chamber reformatted images. For all assessments, sensitivities and specificities for predicting PE-related death within 30-days and a composite outcome including PE-related death or the need for intensive therapies were compared. The agreement between two readers was 91.5% (kappa = 0.83) and all other assessments had pair-wise agreement over 75% (kappa = 0.53-0.72). There was no significant difference in sensitivity between the subjective and objective methods for predicting both outcomes. The specificity for subjective RV enlargement (55.4-67.7%) was significantly higher than objective measures (45.8-53.1%), except for the 4-chamber views where, for one reader, the specificity of the subjective evaluation was higher but did not reach statistical significance. Complex measurements of RV/LV diameter ratios may not be needed to maximize the prognostic value from CTPA. The radiologist who interprets the CTPA images should report RV enlargement when the RV diameter subjectively appears larger than the LV.

  12. Molecular weight enlargement--a molecular approach to continuous homogeneous catalysis.

    PubMed

    Janssen, Michèle; Müller, Christian; Vogt, Dieter

    2010-09-28

    Molecular weight enlargement (MWE) is an attractive method for homogeneous catalyst recycling. Applications of MWE in combination with either catalyst precipitation or nanofiltration have demonstrated their great potential as a method for process intensification in homogeneous catalysis. Selected, recent advances in MWE in combination with catalyst recovery are discussed, together with their implication for future developments. These examples demonstrate that this strategy is applicable in many different homogeneously catalyzed transformations.

  13. 65. March 1978. Copy of enlargement from original 11Omm blackandwhite ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    65. March 1978. Copy of enlargement from original 11Omm black-and-white aerial negative from Sortie 414, made by United States Air Force, Tactical Reconaissance Wing, Ninth Air Force, at Shaw Air Force Base, Sumter, South Carolina. Overhead aerial view of Borough House with surrounding grounds and adjacent properties. - Borough House, West Side State Route 261, about .1 mile south side of junction with old Garners Ferry Road, Stateburg, Sumter County, SC

  14. Intramucosal melanotic nevi - A case report of an unusual gingival enlargement.

    PubMed

    Agrawal, Jyoti

    2013-03-01

    Intramucosal melanotic nevus with multiple polypoid presentations in oral cavity is rare; though single nevus is not uncommon. Nevi are benign proliferations of nevus cells either in the epithelium or in the subepithelial stroma. They are best categorized as hamartomas rather than true neoplasm. We present a case of intramucosal melanotic nevi in a 26-year-old male patient, which clinically resembled hereditary fibrous gingival enlargement.

  15. Enlarged clitoris in wild polar bears (Ursus maritimus) can be misdiagnosed as pseudohermaphroditism.

    PubMed

    Sonne, C; Leifsson, P S; Dietz, R; Born, E W; Letcher, R J; Kirkegaard, M; Muir, D C G; Andersen, L W; Riget, F F; Hyldstrup, L

    2005-01-20

    A 23-year-old female polar bear (Ursus maritimus) killed in an Inuit hunt in East Greenland on July 9, 1999 had a significantly enlarged clitoris resembling, in size, form and colour, those of previously reported 'pseudohermaphroditic' polar bears from Svalbard. It has been suggested that an enzyme defect (21-hydroxylase deficiency), androgen producing tumour or high exposure to organochlorines during the foetal stage or early development could be the reason for the supposed pseudohermaphroditism observed for Svalbard bears. Except for the enlarged clitoris, all dimensions of the external and internal reproductive organs of the present were similar to a reference group of 23 normal adult female polar bears from East Greenland collected in 1999-2002. The aberrant bear was a female genotype, and macroscopic examination of her internal reproductive organs indicated that she was reproductively functional. A histological examination of the clitoral enlargement in the present East Greenland specimen allows a first-time histological evaluation of the earlier macroscopic field diagnosis from Svalbard. This examination revealed intense chronic ulcerative and perivascular clitoriditis similar to "acral lick dermatitis" frequently seen in domestic dogs (i.e., we did not find any signs of pseudohermaphroditic hyperplasia of clitoral tissue due to androgenic or antiestrogenic endocrine disruption). The levels of organohalogens and TEQ values were lower than concentration thresholds of toxicological risk. It is hence possible that the previously reported adult female polar bear pseudohermaphrodites from Svalbard are in fact misdiagnoses. Therefore, future studies examining pseudohermaphroditism in wildlife should consider that certain occurrences are natural events, e.g., enlarged clitoris in the present East Greenland polar bear. Furthermore, caution should be exercised in suggesting linkages of such inflammatory abnormalities with correlations to anthropogenic pollutant

  16. Motor imagery of hand actions: Decoding the content of motor imagery from brain activity in frontal and parietal motor areas.

    PubMed

    Pilgramm, Sebastian; de Haas, Benjamin; Helm, Fabian; Zentgraf, Karen; Stark, Rudolf; Munzert, Jörn; Krüger, Britta

    2016-01-01

    How motor maps are organized while imagining actions is an intensely debated issue. It is particularly unclear whether motor imagery relies on action-specific representations in premotor and posterior parietal cortices. This study tackled this issue by attempting to decode the content of motor imagery from spatial patterns of Blood Oxygen Level Dependent (BOLD) signals recorded in the frontoparietal motor imagery network. During fMRI-scanning, 20 right-handed volunteers worked on three experimental conditions and one baseline condition. In the experimental conditions, they had to imagine three different types of right-hand actions: an aiming movement, an extension-flexion movement, and a squeezing movement. The identity of imagined actions was decoded from the spatial patterns of BOLD signals they evoked in premotor and posterior parietal cortices using multivoxel pattern analysis. Results showed that the content of motor imagery (i.e., the action type) could be decoded significantly above chance level from the spatial patterns of BOLD signals in both frontal (PMC, M1) and parietal areas (SPL, IPL, IPS). An exploratory searchlight analysis revealed significant clusters motor- and motor-associated cortices, as well as in visual cortices. Hence, the data provide evidence that patterns of activity within premotor and posterior parietal cortex vary systematically with the specific type of hand action being imagined. PMID:26452176

  17. The role of fronto-parietal and fronto-striatal networks in the development of working memory: a longitudinal study.

    PubMed

    Darki, Fahimeh; Klingberg, Torkel

    2015-06-01

    The increase in working memory (WM) capacity is an important part of cognitive development during childhood and adolescence. Cross-sectional analyses have associated this development with higher activity, thinner cortex, and white matter maturation in fronto-parietal networks. However, there is still a lack of longitudinal data showing the dynamics of this development and the role of subcortical structures. We included 89 individuals, aged 6-25 years, who were scanned 1-3 times at 2-year intervals. Functional magnetic resonance imaging (fMRI) was used to identify activated areas in superior frontal, intraparietal cortices, and caudate nucleus during performance on a visuo-spatial WM task. Probabilistic tractography determined the anatomical pathways between these regions. In the cross-sectional analysis, WM capacity correlated with activity in frontal and parietal regions, cortical thickness in parietal cortex, and white matter structure [both fractional anisotropy (FA) and white matter volume] of fronto-parietal and fronto-striatal tracts. However, in the longitudinal analysis, FA in white matter tracts and activity in caudate predicted future WM capacity. The results show a dynamic of neural networks underlying WM development in which cortical activity and structure relate to current capacity, while white matter tracts and caudate activity predict future WM capacity.

  18. Modulation of a Fronto-Parietal Network in Event-Based Prospective Memory: An rTMS Study

    ERIC Educational Resources Information Center

    Bisiacchi, P. S.; Cona, G.; Schiff, S.; Basso, D.

    2011-01-01

    Event-based prospective memory (PM) is a multi-component process that requires remembering the delayed execution of an intended action in response to a pre-specified PM cue, while being actively engaged in an ongoing task. Some neuroimaging studies have suggested that both prefrontal and parietal areas are involved in the maintenance and…

  19. Motor imagery of hand actions: Decoding the content of motor imagery from brain activity in frontal and parietal motor areas

    PubMed Central

    Pilgramm, Sebastian; de Haas, Benjamin; Helm, Fabian; Zentgraf, Karen; Stark, Rudolf; Munzert, Jörn

    2015-01-01

    Abstract How motor maps are organized while imagining actions is an intensely debated issue. It is particularly unclear whether motor imagery relies on action‐specific representations in premotor and posterior parietal cortices. This study tackled this issue by attempting to decode the content of motor imagery from spatial patterns of Blood Oxygen Level Dependent (BOLD) signals recorded in the frontoparietal motor imagery network. During fMRI‐scanning, 20 right‐handed volunteers worked on three experimental conditions and one baseline condition. In the experimental conditions, they had to imagine three different types of right‐hand actions: an aiming movement, an extension–flexion movement, and a squeezing movement. The identity of imagined actions was decoded from the spatial patterns of BOLD signals they evoked in premotor and posterior parietal cortices using multivoxel pattern analysis. Results showed that the content of motor imagery (i.e., the action type) could be decoded significantly above chance level from the spatial patterns of BOLD signals in both frontal (PMC, M1) and parietal areas (SPL, IPL, IPS). An exploratory searchlight analysis revealed significant clusters motor‐ and motor‐associated cortices, as well as in visual cortices. Hence, the data provide evidence that patterns of activity within premotor and posterior parietal cortex vary systematically with the specific type of hand action being imagined. Hum Brain Mapp 37:81–93, 2016. © 2015 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:26452176

  20. Posterior Parietal Cortex and Episodic Encoding: Insights from fMRI Subsequent Memory Effects and Dual Attention Theory

    PubMed Central

    Uncapher, Melina; Wagner, Anthony D.

    2010-01-01

    The formation of episodic memories –– memories for life events –– is affected by attention during event processing. A leading neurobiological model of attention posits two separate yet interacting systems that depend on distinct regions in lateral posterior parietal cortex (PPC). From this dual-attention perspective, dorsal PPC is thought to support the goal-directed allocation of attention, whereas ventral PPC is thought to support reflexive orienting to information that automatically captures attention. To advance understanding of how parietal mechanisms may impact event encoding, we review functional MRI studies that document the relationship between lateral PPC activation during encoding and subsequent memory performance (e.g., later remembering or forgetting). This review reveals that (a) encoding-related activity is frequently observed in human lateral PPC, (b) increased activation in dorsal PPC is associated with later memory success, and (c) increased activation in ventral PPC predominantly correlates with later memory failure. From a dual-attention perspective, these findings suggest that allocating goal-directed attention during event processing increases the probability that the event will be remembered later, whereas the capture of reflexive attention during event processing may have negative consequences for event encoding. The prevalence of encoding-related activation in parietal cortex suggests that neurobiological models of episodic memory should consider how parietal-mediated attentional mechanisms regulate encoding. PMID:19028591

  1. At the Intersection of Attention and Memory: The Mechanistic Role of the Posterior Parietal Lobe in Working Memory

    ERIC Educational Resources Information Center

    Berryhill, Marian E.; Chein, Jason; Olson, Ingrid R.

    2011-01-01

    Portions of the posterior parietal cortex (PPC) play a role in working memory (WM) yet the precise mechanistic function of this region remains poorly understood. The "pure storage" hypothesis proposes that this region functions as a short-lived modality-specific memory store. Alternatively, the "internal attention" hypothesis proposes that the PPC…

  2. Why I tense up when you watch me: Inferior parietal cortex mediates an audience’s influence on motor performance

    PubMed Central

    Yoshie, Michiko; Nagai, Yoko; Critchley, Hugo D.; Harrison, Neil A.

    2016-01-01

    The presence of an evaluative audience can alter skilled motor performance through changes in force output. To investigate how this is mediated within the brain, we emulated real-time social monitoring of participants’ performance of a fine grip task during functional magnetic resonance neuroimaging. We observed an increase in force output during social evaluation that was accompanied by focal reductions in activity within bilateral inferior parietal cortex. Moreover, deactivation of the left inferior parietal cortex predicted both inter- and intra-individual differences in socially-induced change in grip force. Social evaluation also enhanced activation within the posterior superior temporal sulcus, which conveys visual information about others’ actions to the inferior parietal cortex. Interestingly, functional connectivity between these two regions was attenuated by social evaluation. Our data suggest that social evaluation can vary force output through the altered engagement of inferior parietal cortex; a region implicated in sensorimotor integration necessary for object manipulation, and a component of the action-observation network which integrates and facilitates performance of observed actions. Social-evaluative situations may induce high-level representational incoherence between one’s own intentioned action and the perceived intention of others which, by uncoupling the dynamics of sensorimotor facilitation, could ultimately perturbe motor output. PMID:26787326

  3. Why I tense up when you watch me: Inferior parietal cortex mediates an audience's influence on motor performance.

    PubMed

    Yoshie, Michiko; Nagai, Yoko; Critchley, Hugo D; Harrison, Neil A

    2016-01-01

    The presence of an evaluative audience can alter skilled motor performance through changes in force output. To investigate how this is mediated within the brain, we emulated real-time social monitoring of participants' performance of a fine grip task during functional magnetic resonance neuroimaging. We observed an increase in force output during social evaluation that was accompanied by focal reductions in activity within bilateral inferior parietal cortex. Moreover, deactivation of the left inferior parietal cortex predicted both inter- and intra-individual differences in socially-induced change in grip force. Social evaluation also enhanced activation within the posterior superior temporal sulcus, which conveys visual information about others' actions to the inferior parietal cortex. Interestingly, functional connectivity between these two regions was attenuated by social evaluation. Our data suggest that social evaluation can vary force output through the altered engagement of inferior parietal cortex; a region implicated in sensorimotor integration necessary for object manipulation, and a component of the action-observation network which integrates and facilitates performance of observed actions. Social-evaluative situations may induce high-level representational incoherence between one's own intentioned action and the perceived intention of others which, by uncoupling the dynamics of sensorimotor facilitation, could ultimately perturbe motor output. PMID:26787326

  4. Temporal and Motor Representation of Rhythm in Fronto-Parietal Cortical Areas: An fMRI Study

    PubMed Central

    Konoike, Naho; Kotozaki, Yuka; Jeong, Hyeonjeong; Miyazaki, Atsuko; Sakaki, Kohei; Shinada, Takamitsu; Sugiura, Motoaki; Kawashima, Ryuta; Nakamura, Katsuki

    2015-01-01

    When sounds occur with temporally structured patterns, we can feel a rhythm. To memorize a rhythm, perception of its temporal patterns and organization of them into a hierarchically structured sequence are necessary. On the other hand, rhythm perception can often cause unintentional body movements. Thus, we hypothesized that rhythm information can be manifested in two different ways; temporal and motor representations. The motor representation depends on effectors, such as the finger or foot, whereas the temporal representation is effector-independent. We tested our hypothesis with a working memory paradigm to elucidate neuronal correlates of temporal or motor representation of rhythm and to reveal the neural networks associated with these representations. We measured brain activity by fMRI while participants memorized rhythms and reproduced them by tapping with the right finger, left finger, or foot, or by articulation. The right inferior frontal gyrus and the inferior parietal lobule exhibited significant effector-independent activations during encoding and retrieval of rhythm information, whereas the left inferior parietal lobule and supplementary motor area (SMA) showed effector-dependent activations during retrieval. These results suggest that temporal sequences of rhythm are probably represented in the right fronto-parietal network, whereas motor sequences of rhythm can be represented in the SMA-parietal network. PMID:26076024

  5. Right Fronto-Parietal Dysfunction in Children with ADHD and Developmental Dyslexia as Determined by Line Bisection Judgements

    ERIC Educational Resources Information Center

    Waldie, Karen E.; Hausmann, Markus

    2010-01-01

    Visual line bisection is a reliable and valid laterality task that is typically used with patients with acquired brain damage to assess right hemisphere functioning. Neurologically normal individuals tend to bisect lines to the left of the objective midline whereas those with right parietal damage bisect lines to the right. In this study children…

  6. Genetic Ablation of Parietal Cells in Transgenic Mice: A New Model for Analyzing Cell Lineage Relationships in the Gastric Mucosa

    NASA Astrophysics Data System (ADS)

    Canfield, Victor; West, A. Brian; Goldenring, James R.; Levenson, Robert

    1996-03-01

    The gastric mucosa of mammalian stomach contains several differentiated cell types specialized for the secretion of acid, digestive enzymes, mucus, and hormones. Understanding whether each of these cell lineages is derived from a common stem cell has been a challenging problem. We have used a genetic approach to analyze the ontogeny of progenitor cells within mouse stomach. Herpes simplex virus 1 thymidine kinase was targeted to parietal cells within the gastric mucosa of transgenic mice, and parietal cells were ablated by treatment of animals with the antiherpetic drug ganciclovir. Ganciclovir treatment produced complete ablation of parietal cells, dissolution of gastric glands, and loss of chief and mucus-producing cells. Termination of drug treatment led to the reemergence of all major gastric epithelial cell types and restoration of glandular architecture. Our results imply the existence of a pluripotent stem cell for the gastric mucosa. Parietal cell ablation should provide a model for analyzing cell lineage relationships within the stomach as well as mechanisms underlying gastric injury and repair.

  7. The Significance of Macrocephaly or Enlarging Head Circumference in Infants With the Triad

    PubMed Central

    Miller, David; Barnes, Patrick; Miller, Marvin

    2015-01-01

    Abstract Infants with the triad (neurologic dysfunction, subdural hematoma [SDH], and retinal hemorrhage) are often diagnosed as victims of shaken baby syndrome. Medical conditions/predisposing factors to developing the triad are often dismissed: short falls, birth-related SDH that enlarges, macrocephaly, sinus/cortical vein thrombosis, and others. Six infants with the triad are described in which child abuse was diagnosed, but parents denied wrongdoing. All 6 had either macrocephaly or enlarging head circumference, which suggested medical explanations. Three infants incurred short falls, 1 had a difficult delivery in which there was likely a rebleed of a birth-related SDH, 1 had a spontaneous SDH associated with increased extra-axial fluid spaces, and 1 had a sinus thrombosis. Following legal proceedings, all 6 infants were returned to their parents, and there has been no child maltreatment in follow-up, suggesting child abuse never happened. The results indicate that alternative medical explanations for causing the triad should be considered and that macrocephaly or an enlarging head circumference raises the possibility of a medical explanation. PMID:25893912

  8. Association between gingivitis and anterior gingival enlargement in subjects undergoing fixed orthodontic treatment

    PubMed Central

    Zanatta, Fabricio Batistin; Ardenghi, Thiago Machado; Antoniazzi, Raquel Pippi; Pinto, Tatiana Militz Perrone; Rösing, Cassiano Kuchenbecker

    2014-01-01

    Objective The aim of this study was to investigate the association among gingival enlargement (GE), periodontal conditions and socio-demographic characteristics in subjects undergoing fixed orthodontic treatment. Methods A sample of 330 patients undergoing fixed orthodontic treatment for at least 6 months were examined by a single calibrated examiner for plaque and gingival indexes, probing pocket depth, clinical attachment loss and gingival enlargement. Socio-economic background, orthodontic treatment duration and use of dental floss were assessed by oral interviews. Associations were assessed by means of unadjusted and adjusted Poisson's regression models. Results The presence of gingival bleeding (RR 1.01; 95% CI 1.00-1.01) and excess resin around brackets (RR 1.02; 95% CI 1.02-1.03) were associated with an increase in GE. No associations were found between socio-demographic characteristics and GE. Conclusion Proximal anterior gingival bleeding and excess resin around brackets are associated with higher levels of anterior gingival enlargement in subjects under orthodontic treatment. PMID:25162567

  9. Kleptochloroplast Enlargement, Karyoklepty and the Distribution of the Cryptomonad Nucleus in Nusuttodinium (= Gymnodinium) aeruginosum (Dinophyceae).

    PubMed

    Onuma, Ryo; Horiguchi, Takeo

    2015-05-01

    The unarmoured freshwater dinoflagellate Nusuttodinium (= Gymnodinium) aeruginosum retains a cryptomonad-derived kleptochloroplast and nucleus, the former of which fills the bulk of its cell volume. The paucity of studies following morphological changes to the kleptochloroplast with time make it unclear how the kleptochloroplast enlarges and why the cell ultimately loses the cryptomonad nucleus. We observed, both at the light and electron microscope level, morphological changes to the kleptochloroplast incurred by the enlargement process under culture conditions. The distribution of the cryptomonad nucleus after host cell division was also investigated. The volume of the kleptochloroplast increased more than 20-fold, within 120h of ingestion of the cryptomonad. Host cell division was not preceded by cryptomonad karyokinesis so that only one of the daughter cells inherited a cryptomonad nucleus. The fate of all daughter cells originating from a single cell through five generations was closely monitored, and this observation revealed that the cell that inherited the cryptomonad nucleus consistently possessed the largest kleptochloroplast for that generation. Therefore, this study suggests that some important cryptomonad nucleus division mechanism is lost during ingestion process, and that the cryptomonad nucleus carries important information for the enlargement of the kleptochloroplast.

  10. Developmental basis for telencephalon expansion in waterfowl: enlargement prior to neurogenesis

    PubMed Central

    Charvet, Christine J.; Striedter, Georg F.

    2009-01-01

    Some altricial and some precocial species of birds have evolved enlarged telencephalons compared with other birds. Previous work has shown that finches and parakeets, two species that hatch in an immature (i.e. altricial) state, enlarged their telencephalon by delaying telencephalic neurogenesis. To determine whether species that hatch in a relatively mature (i.e. precocial) state also enlarged their telencephalon by delaying telencephalic neurogenesis, we examined brain development in geese, ducks, turkeys and chickens, which are all precocial. Whereas the telencephalon occupies less than 55 per cent of the brain in chickens and turkeys, it occupies more than 65 per cent in ducks and geese. To determine how these species differences in adult brain region proportions arise during development, we examined brain maturation (i.e. neurogenesis timing) and estimated telencephalon, tectum and medulla volumes from serial Nissl-stained sections in the four species. We found that incubation time predicts the timing of neurogenesis in all major brain regions and that the telencephalon is proportionally larger in ducks and geese before telencephalic neurogenesis begins. These findings demonstrate that the expansion of the telencephalon in ducks and geese is achieved by altering development prior to neurogenesis onset. Thus, precocial and altricial species evolved different developmental strategies to expand their telencephalon. PMID:19605398

  11. Channel enlargement in semiarid suburbanizing watersheds: A southern California case study

    NASA Astrophysics Data System (ADS)

    Hawley, R. J.; Bledsoe, B. P.

    2013-07-01

    Semiarid channels exhibit an extreme sensitivity to upstream urban development, particularly in unconfined valleys with unprotected grades. For example, one of our study streams in southern California has increased its cross-sectional area by nearly 14-fold relative to its pre-developed channel form in a watershed that has been only lightly developed (10.4% imperviousness). Multivariate regression models of cross-sectional channel enlargement at 61 sites were highly dependent on the ratio of post- to pre-urban sediment-transport capacity over cumulative duration simulations of 25 yrs (Lr), which explained nearly 60% of the variance. The proximity of a channel hard point such as bedrock or artificial grade control was also significant, indicating that channel enlargement increased moving upstream from grade control. The enlargement models point to the importance of balancing the post-developed sediment transport to the pre-developed setting over an entire range of flows rather than a single flow in order to reduce the risk of adverse channel responses to hydromodification. The need for controlling a wide range of flows was underscored by logistic-regression analyses that indicated a high risk of instability in systems with Lr > 1, especially for fine-grained systems (i.e., d50 < 16 mm).

  12. Hippocampal atrophy and ventricular enlargement in normal aging, mild cognitive impairment (MCI), and Alzheimer Disease.

    PubMed

    Apostolova, Liana G; Green, Amity E; Babakchanian, Sona; Hwang, Kristy S; Chou, Yi-Yu; Toga, Arthur W; Thompson, Paul M

    2012-01-01

    Alzheimer disease (AD) is the most common type of dementia worldwide. Hippocampal atrophy and ventricular enlargement have been associated with AD but also with normal aging. We analyzed 1.5-T brain magnetic resonance imaging data from 46 cognitively normal elderly individuals (NC), 33 mild cognitive impairment and 43 AD patients. Hippocampal and ventricular analyses were conducted with 2 novel semiautomated segmentation approaches followed by the radial distance mapping technique. Multiple linear regression was used to assess the effects of age and diagnosis on hippocampal and ventricular volumes and radial distance. In addition, 3-dimensional map correction for multiple comparisons was made with permutation testing. As expected, most significant hippocampal atrophy and ventricular enlargement were seen in the AD versus NC comparison. Mild cognitive impairment patients showed intermediate levels of hippocampal atrophy and ventricular enlargement. Significant effects of age on hippocampal volume and radial distance were seen in the pooled sample and in the NC and AD groups considered separately. Age-associated differences were detected in all hippocampal subfields and in the frontal and body/occipital horn portions of the lateral ventricles. Aging affects both the hippocampus and lateral ventricles independent of AD pathology, and should be included as covariate in all structural, hippocampal, and ventricular analyses when possible.

  13. Renal Epithelial Cyst Formation and Enlargement in vitro: Dependence on cAMP

    NASA Astrophysics Data System (ADS)

    Mangoo-Karim, Roberto; Uchic, Marie; Lechene, Claude; Grantham, Jared J.

    1989-08-01

    Cysts, a common abnormality of kidneys, are collections of urine-like fluid enclosed by a continuous layer of epithelial cells. Renal cysts derive from nephrons and collecting ducts and progressively enlarge as a consequence of epithelial proliferation and transepithelial fluid secretion. The initiation of cyst formation and the factors that control cyst enlargement are unknown. We used an in vitro model of renal cysts to explore the role of the cAMP signal transduction system in the formation and expansion of cysts. MDCK cells, cultured in hydrated-collagen gel, produced polarized monolayered epithelial cysts when intracellular cAMP was increased by prostaglandin E1, arginine vasopressin, cholera toxin, forskolin, or 8-bromoadenosine 3',5'-cyclic monophosphate. All agonists were potentiated by 3-isobutyl-1-methylxanthine, a nucleotide phosphodiesterase inhibitor. The cell proliferation component of cyst enlargement was accelerated by cAMP agonists, as shown by the increased growth of MDCK cells in subconfluent monolayers. The fluid secretion component, reflected by the transepithelial movement of fluid across polarized monolayers of MDCK cells grown on permeable supports, was stimulated by cAMP agonists in the basolateral medium. Chloride levels were higher in the cyst fluid and the secreted fluid than in the bathing medium. We conclude that the development of MDCK cysts is dependent on cAMP. This signal transduction system may be an important modulator of epithelial cell proliferation and transepithelial fluid secretion in the kidney.

  14. Kleptochloroplast Enlargement, Karyoklepty and the Distribution of the Cryptomonad Nucleus in Nusuttodinium (= Gymnodinium) aeruginosum (Dinophyceae).

    PubMed

    Onuma, Ryo; Horiguchi, Takeo

    2015-05-01

    The unarmoured freshwater dinoflagellate Nusuttodinium (= Gymnodinium) aeruginosum retains a cryptomonad-derived kleptochloroplast and nucleus, the former of which fills the bulk of its cell volume. The paucity of studies following morphological changes to the kleptochloroplast with time make it unclear how the kleptochloroplast enlarges and why the cell ultimately loses the cryptomonad nucleus. We observed, both at the light and electron microscope level, morphological changes to the kleptochloroplast incurred by the enlargement process under culture conditions. The distribution of the cryptomonad nucleus after host cell division was also investigated. The volume of the kleptochloroplast increased more than 20-fold, within 120h of ingestion of the cryptomonad. Host cell division was not preceded by cryptomonad karyokinesis so that only one of the daughter cells inherited a cryptomonad nucleus. The fate of all daughter cells originating from a single cell through five generations was closely monitored, and this observation revealed that the cell that inherited the cryptomonad nucleus consistently possessed the largest kleptochloroplast for that generation. Therefore, this study suggests that some important cryptomonad nucleus division mechanism is lost during ingestion process, and that the cryptomonad nucleus carries important information for the enlargement of the kleptochloroplast. PMID:25771111

  15. To-and-fro optical voltage signal propagation between the insular gustatory and parietal oral somatosensory areas in rat cortex slices.

    PubMed

    Yoshimura, Hiroshi; Kato, Nobuo; Sugai, Tokio; Honjo, Makoto; Sato, Jun; Segami, Natsuki; Onoda, Norihiko

    2004-07-23

    Taste perception depends not only on special taste information processed in the insular cortex, but also on oral somesthetic processing in the parietal cortex. Many insular cortex neurons show multimodal responsiveness. Such multimodality may be enabled by signal exchange between these two cortices. By using the protocol that we have developed, a synchronized population oscillation of synaptic potentials was induced in the parietal cortex by stimulation to the insular cortex in rat neocortex slices. The spatiotemporal pattern of propagation of this oscillation was studied by recording voltage-sensitive optical signals and field potentials. The first wavelet of the oscillation was propagated from the insular stimulation site to the parietal cortex. However, the second and later wavelets propagated back from the parietal cortex to the insular cortex. The oscillation was detected in the insular cortex as well, but was actually generated in the parietal cortex. Thus, the initial peak of optical signal, sent from the insular to parietal cortex, served to generate oscillatory responses in the parietal cortex, which propagated back to the insular cortex wave-by-wave. We propose that this to-and-fro propagation may be an artificially exaggerated demonstration of an intrinsic mechanism relevant to signal exchange between the parietal and insular cortices.

  16. The Role of Right Inferior Parietal Cortex in Auditory Spatial Attention: A Repetitive Transcranial Magnetic Stimulation Study

    PubMed Central

    Karhson, Debra S.; Mock, Jeffrey R.; Golob, Edward J.

    2015-01-01

    Behavioral studies support the concept of an auditory spatial attention gradient by demonstrating that attentional benefits progressively diminish as distance increases from an attended location. Damage to the right inferior parietal cortex can induce a rightward attention bias, which implicates this region in the construction of attention gradients. This study used event-related potentials (ERPs) to define attention-related gradients before and after repetitive transcranial magnetic stimulation (rTMS) to the right inferior parietal cortex. Subjects (n = 16) listened to noise bursts at five azimuth locations (left to right: -90°, -45°, 0° midline, +45°, +90°) and responded to stimuli at one target location (-90°, +90°, separate blocks). ERPs as a function of non-target location were examined before (baseline) and after 0.9 Hz rTMS. Results showed that ERP attention gradients were observed in three time windows (frontal 230–340, parietal 400–460, frontal 550–750 ms). Significant transient rTMS effects were seen in the first and third windows. The first window had a voltage decrease at the farthest location when attending to either the left or right side. The third window had on overall increase in positivity, but only when attending to the left side. These findings suggest that rTMS induced a small contraction in spatial attention gradients within the first time window. The asymmetric effect of attended location on gradients in the third time window may relate to neglect of the left hemispace after right parietal injury. Together, these results highlight the role of the right inferior parietal cortex in modulating frontal lobe attention network activity. PMID:26636333

  17. The impact of top-down spatial attention on laterality and hemispheric asymmetry in the human parietal cortex

    PubMed Central

    Jeong, Su Keun; Xu, Yaoda

    2016-01-01

    The human parietal cortex exhibits a preference to contralaterally presented visual stimuli (i.e., laterality) as well as an asymmetry between the two hemispheres with the left parietal cortex showing greater laterality than the right. Using visual short-term memory and perceptual tasks and varying target location predictability, this study examined whether hemispheric laterality and asymmetry are fixed characteristics of the human parietal cortex or whether they are dynamic and modulated by the deployment of top-down attention to the target present hemifield. Two parietal regions were examined here that have previously been shown to be involved in visual object individuation and identification and are located in the inferior and superior intraparietal sulcus (IPS), respectively. Across three experiments, significant laterality was found in both parietal regions regardless of attentional modulation with laterality being greater in the inferior than superior IPS, consistent with their roles in object individuation and identification, respectively. Although the deployment of top-down attention had no effect on the superior IPS, it significantly increased laterality in the inferior IPS. The deployment of top-down spatial attention can thus amplify the strength of laterality in the inferior IPS. Hemispheric asymmetry, on the other hand, was absent in both brain regions and only emerged in the inferior but not the superior IPS with the deployment of top-down attention. Interestingly, the strength of hemispheric asymmetry significantly correlated with the strength of laterality in the inferior IPS. Hemispheric asymmetry thus seems to only emerge when there is a sufficient amount of laterality present in a brain region. PMID:27494544

  18. The impact of top-down spatial attention on laterality and hemispheric asymmetry in the human parietal cortex.

    PubMed

    Jeong, Su Keun; Xu, Yaoda

    2016-08-01

    The human parietal cortex exhibits a preference to contralaterally presented visual stimuli (i.e., laterality) as well as an asymmetry between the two hemispheres with the left parietal cortex showing greater laterality than the right. Using visual short-term memory and perceptual tasks and varying target location predictability, this study examined whether hemispheric laterality and asymmetry are fixed characteristics of the human parietal cortex or whether they are dynamic and modulated by the deployment of top-down attention to the target present hemifield. Two parietal regions were examined here that have previously been shown to be involved in visual object individuation and identification and are located in the inferior and superior intraparietal sulcus (IPS), respectively. Across three experiments, significant laterality was found in both parietal regions regardless of attentional modulation with laterality being greater in the inferior than superior IPS, consistent with their roles in object individuation and identification, respectively. Although the deployment of top-down attention had no effect on the superior IPS, it significantly increased laterality in the inferior IPS. The deployment of top-down spatial attention can thus amplify the strength of laterality in the inferior IPS. Hemispheric asymmetry, on the other hand, was absent in both brain regions and only emerged in the inferior but not the superior IPS with the deployment of top-down attention. Interestingly, the strength of hemispheric asymmetry significantly correlated with the strength of laterality in the inferior IPS. Hemispheric asymmetry thus seems to only emerge when there is a sufficient amount of laterality present in a brain region. PMID:27494544

  19. The organization of the posterior parietal cortex devoted to upper limb actions: An fMRI study

    PubMed Central

    Ferri, Stefania; Rizzolatti, Giacomo

    2015-01-01

    Abstract The present fMRI study examined whether upper‐limb action classes differing in their motor goal are encoded by different PPC sectors. Action observation was used as a proxy for action execution. Subjects viewed actors performing object‐related (e.g., grasping), skin‐displacing (e.g., rubbing the skin), and interpersonal upper limb actions (e.g., pushing someone). Observation of the three action classes activated a three‐level network including occipito‐temporal, parietal, and premotor cortex. The parietal region common to observing all three action classes was located dorsally to the left intraparietal sulcus (DIPSM/DIPSA border). Regions specific for observing an action class were obtained by combining the interaction between observing action classes and stimulus types with exclusive masking for observing the other classes, while for regions considered preferentially active for a class the interaction was exclusively masked with the regions common to all observed actions. Left putative human anterior intraparietal was specific for observing manipulative actions, and left parietal operculum including putative human SII region, specific for observing skin‐displacing actions. Control experiments demonstrated that this latter activation depended on seeing the skin being moved and not simply on seeing touch. Psychophysiological interactions showed that the two specific parietal regions had similar connectivities. Finally, observing interpersonal actions preferentially activated a dorsal sector of left DIPSA, possibly the homologue of ventral intraparietal coding the impingement of the target person's body into the peripersonal space of the actor. These results support the importance of segregation according to the action class as principle of posterior parietal cortex organization for action observation and by implication for action execution. Hum Brain Mapp 36:3845–3866, 2015. © 2015 The Authors Human Brain Mapping Published by Wiley

  20. Decoding the superior parietal lobule connections of the superior longitudinal fasciculus/arcuate fasciculus in the human brain.

    PubMed

    Kamali, A; Sair, H I; Radmanesh, A; Hasan, K M

    2014-09-26

    The temporo-parietal (TP) white matter connections between the inferior parietal lobule and superior temporal gyrus as part of the superior longitudinal fasciculus/arcuate fasciculus (SLF/AF) or middle longitudinal fasciculus (MdLF) have been studied in prior diffusion tensor tractography (DTT) studies. However, few studies have been focusing on the higher TP connections of the superior parietal lobule with the temporal lobe. These higher TP connections have been shown to have a role in core processes such as attention, memory, emotions, and language. Our most recent study, for the first time, hinted to the possibility of a long white matter connection interconnecting the superior parietal lobule (SPL) with the posterior temporal lobe in human brain which we call the SLF/AF TP-SPL and for a shorter abbreviation, the TP-SPL. We decided to further investigate this white matter connection using fiber assignment by continuous tracking deterministic tractography and high spatial resolution diffusion tensor imaging on 3T. Five healthy right-handed men (age range 24-37 years) were studied. We delineated the SPL connections of the SLF/AF TP bilaterally in five normal adult human brains. Using a high resolution DTT technique, we demonstrate for the first time, the trajectory of a long fiber bundle connectivity between the SPL and posterior temporal lobe, called the SLF/AF TP-SPL (or the TP-SPL), bilaterally in five healthy adult human brains. We also demonstrate the trajectory of the vertically oriented posterior TP connections, interconnecting the inferior parietal lobule (IPL) with the posterior temporal lobe (TP-IPL) in relation to the TP-SPL, arcuate fasciculus and other major language pathways. In the current study, for the first time, we categorized the TP connections into the anterior and posterior connectivity groups and subcategorized each one into the SPL or IPL connections. PMID:25086308