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Sample records for memory prevents scopolamine-induced

  1. Prevention of scopolamine-induced memory deficits by schisandrin B, an antioxidant lignan from Schisandra chinensis in mice.

    PubMed

    Giridharan, Vijayasree V; Thandavarayan, Rajarajan A; Sato, Shinji; Ko, Kam Ming; Konishi, Tetsuya

    2011-08-01

    The preventive effect of schisandrin B (Sch B), an antioxidant ingredient of Schisandra chinensis, was studied on scopolamine-induced dementia in mouse. Scopolamine developed oxidative stress in the brain with the decreased levels of antioxidant enzymes and increased nitrite level. At the same time, a significant impairment of learning and memory occurred when evaluated by passive avoidance task (PAT) and Morris water maze (MWM) with concomitant increase of acetylcholinesterase (AChE) activity and decreased acetylcholine levels. Pre-treatment by Sch B (10, 25, 50 mg/kg) effectively prevented scopolamine-induced oxidative stress and improved behavioural tasks. Further, the scopolamine-induced increase in AChE activity was significantly suppressed and the level of acetylcholine was maintained as normal by Sch B treatment. These results suggest that Sch B have protective function against cerebral functional defects such as dementia not only by antioxidant prevention but also exerting its potent cognitive-enhancing activity through modulation of acetylcholine level.

  2. Deer bone extract prevents against scopolamine-induced memory impairment in mice.

    PubMed

    Du, Chun Nan; Min, A Young; Kim, Hyun Jeong; Shin, Suk Kyung; Yu, Ha Ni; Sohn, Eun Jeong; Ahn, Chang-Won; Jung, Sung Ug; Park, Soo-Hyun; Kim, Mee Ree

    2015-02-01

    Deer bone has been used as a health-enhancing food as well as an antiaging agent in traditional Oriental medicine. Recently, the water extract of deer bone (DBE) showed a neuroprotective action against glutamate or Aβ1-42-induced cell death of mouse hippocampal cells by exerting antioxidant activity through the suppression of MAP kinases. The present study is to examine whether DBE improves memory impairment induced by scopolamine. DBE (50, 100 or 200 mg/kg) was administered orally to mice for 14 days, and then scopolamine (2 mg/kg, i.p.) was administered together with DBE for another 7 days. Memory performance was evaluated in the Morris water maze (MWM) test and passive avoidance test. Also, brain acetylcholinesterase (AChE) and choline acetyltransferase (ChAT) activity, biomarkers of oxidative stress and the loss of neuronal cells in the hippocampus, was evaluated by histological examinations. Administration of DBE significantly restored memory impairments induced by scopolamine in the MWM test (escape latency and number of crossing platform area), and in the passive avoidance test. Treatment with DBE inhibited the AChE activity and increased the ChAT activity in the brain of memory-impaired mice induced by scopolamine. Additionally, the administration of DBE significantly prevented the increase of lipid peroxidation and the decrease of glutathione level in the brain of mice treated with scopolamine. Also, the DBE treatment restored the activities of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, and glutathione reductase to control the level. Furthermore, scopolamine-induced oxidative damage of neurons in hippocampal CA1 and CA3 regions were prevented by DBE treatment. It is suggested that DBE may be useful for memory improvement through the regulation of cholinergic marker enzyme activities and the suppression of oxidative damage of neurons in the brain of mice treated with scopolamine.

  3. Piracetam prevents scopolamine-induced memory impairment and decrease of NTPDase, 5'-nucleotidase and adenosine deaminase activities.

    PubMed

    Marisco, Patricia C; Carvalho, Fabiano B; Rosa, Michelle M; Girardi, Bruna A; Gutierres, Jessié M; Jaques, Jeandre A S; Salla, Ana P S; Pimentel, Víctor C; Schetinger, Maria Rosa C; Leal, Daniela B R; Mello, Carlos F; Rubin, Maribel A

    2013-08-01

    Piracetam improves cognitive function in animals and in human beings, but its mechanism of action is still not completely known. In the present study, we investigated whether enzymes involved in extracellular adenine nucleotide metabolism, adenosine triphosphate diphosphohydrolase (NTPDase), 5'-nucleotidase and adenosine deaminase (ADA) are affected by piracetam in the hippocampus and cerebral cortex of animals subjected to scopolamine-induced memory impairment. Piracetam (0.02 μmol/5 μL, intracerebroventricular, 60 min pre-training) prevented memory impairment induced by scopolamine (1 mg/kg, intraperitoneal, immediately post-training) in the inhibitory avoidance learning and in the object recognition task. Scopolamine reduced the activity of NTPDase in hippocampus (53 % for ATP and 53 % for ADP hydrolysis) and cerebral cortex (28 % for ATP hydrolysis). Scopolamine also decreased the activity of 5'-nucleotidase (43 %) and ADA (91 %) in hippocampus. The same effect was observed in the cerebral cortex for 5'-nucleotidase (38 %) and ADA (68 %) activities. Piracetam fully prevented scopolamine-induced memory impairment and decrease of NTPDase, 5'-nucleotidase and adenosine deaminase activities in synaptosomes from cerebral cortex and hippocampus. In vitro experiments show that piracetam and scopolamine did not alter enzymatic activity in cerebral cortex synaptosomes. Moreover, piracetam prevented scopolamine-induced increase of TBARS levels in hippocampus and cerebral cortex. These results suggest that piracetam-induced improvement of memory is associated with protection against oxidative stress and maintenance of NTPDase, 5'-nucleotidase and ADA activities, and suggest the purinergic system as a putative target of piracetam.

  4. Dipeptide preparation Noopept prevents scopolamine-induced deficit of spatial memory in BALB/c mice.

    PubMed

    Belnik, A P; Ostrovskaya, R U; Poletaeva, I I

    2007-04-01

    The effect of original nootropic preparation Noopept on learning and long-term memory was studied with BALB/c mice. Scopolamine (1 mg/kg) impaired long-term memory trace, while Noopept (0.5 mg/kg) had no significant effect. Noopept completely prevented the development of cognitive disorders induced by scopolamine (blockade of muscarinic cholinergic receptors). Our results confirmed the presence of choline-positive effect in dipeptide piracetam analogue Noopept on retrieval of learned skill of finding a submerged platform (spatial memory). We conclude that the effectiveness of this drug should be evaluated in patients with Alzheimer's disease.

  5. Caffeine attenuates scopolamine-induced memory impairment in humans.

    PubMed

    Riedel, W; Hogervorst, E; Leboux, R; Verhey, F; van Praag, H; Jolles, J

    1995-11-01

    Caffeine consumption can be beneficial for cognitive functioning. Although caffeine is widely recognized as a mild CNS stimulant drug, the most important consequence of its adenosine antagonism is cholinergic stimulation, which might lead to improvement of higher cognitive functions, particularly memory. In this study, the scopolamine model of amnesia was used to test the cholinergic effects of caffeine, administered as three cups of coffee. Subjects were 16 healthy volunteers who received 250 mg caffeine and 2 mg nicotine separately, in a placebo-controlled double-blind cross-over design. Compared to placebo, nicotine attenuated the scopolamine-induced impairment of storage in short-term memory and attenuated the scopolamine-induced slowing of speed of short-term memory scanning. Nicotine also attenuated the scopolamine-induced slowing of reaction time in a response competition task. Caffeine attenuated the scopolamine-induced impairment of free recall from short- and long-term memory, quality and speed of retrieval from long-term memory in a word learning task, and other cognitive and non-cognitive measures, such as perceptual sensitivity in visual search, reading speed, and rate of finger-tapping. On the basis of these results it was concluded that caffeine possesses cholinergic cognition enhancing properties. Caffeine could be used as a control drug in studies using the scopolamine paradigm and possibly also in other experimental studies of cognitive enhancers, as the effects of a newly developed cognition enhancing drug should at least be superior to the effects of three cups of coffee.

  6. Antiamnesic Effects of Walnuts Consumption on Scopolamine-Induced Memory Impairments in Rats

    PubMed Central

    Harandi, Shaahin; Golchin, Leila; Ansari, Mehdi; Moradi, Alireza; Shabani, Mohammad; Sheibani, Vahid

    2015-01-01

    Introduction: Alzheimer’s disease (AD) is an age-related neurodegenerative disease, which impairs memory and cognitive function. Walnuts are a dietary source of polyphenols, antioxidants and other compounds with health beneficial effects. These characteristic of walnuts make them perfect candidates for evaluation of their possible effects on neurodegenerative diseases. Therefore the present study was designed to investigate the effects of walnuts consumption (2%, 6% and 9% walnut diets) on memory enhancement and acetylcholinesterase (AChE) activity of brain in scopolamine-induced amnesic rats. Methods: Learning, memory and locomotor activity parameters were evaluated using Morris water maze (MWM), passive avoidance and rotarod tests. Results: Our results showed that consumption of walnuts at doses of 6% and 9% significantly restored the scopolamine-induced memory impairments in the MWM and passive avoidance tests. Moreover, the potential of walnuts to prevent scopolamine neurotoxicity was also reflected by the decreased AChE activity in the whole brain in comparison with the scopolamine group. Discussion: These results suggest that walnuts may be useful against memory impairment and it may exert these anti-amnesic activities via inhibition of AChE activity in the brain. It would be worthwhile to explore the potential of this nut and its active components in the management of the AD. PMID:27307953

  7. Rubus coreanus Miquel ameliorates scopolamine-induced memory impairments in ICR mice.

    PubMed

    Choi, Mi-Ran; Lee, Min Young; Hong, Ji Eun; Kim, Jeong Eun; Lee, Jae-Yong; Kim, Tae Hwan; Chun, Jang Woo; Shin, Hyun Kyung; Kim, Eun Ji

    2014-10-01

    The present study investigated the effect of Rubus coreanus Miquel (RCM) on scopolamine-induced memory impairments in ICR mice. Mice were orally administrated RCM for 4 weeks and scopolamine was intraperitoneally injected into mice to induce memory impairment. RCM improved the scopolamine-induced memory impairment in mice. The increase of acetylcholinesterase activity caused by scopolamine was significantly attenuated by RCM treatment. RCM increased the levels of acetylcholine in the brain and serum of mice. The expression of choline acetyltransferase, phospho-cyclic AMP response element-binding protein, and phospho-extracellular signal-regulated kinase was significantly increased within the brain of mice treated with RCM. The brain antioxidant enzyme activity decreased by scopolamine was increased by RCM. These results demonstrate that RCM exerts a memory-enhancing effect via the improvement of cholinergic function and the potentiated antioxidant activity in memory-impaired mice. The results suggest that RCM may be a useful agent for improving memory impairment.

  8. The Effects of Inhaled Pimpinella peregrina Essential Oil on Scopolamine-Induced Memory Impairment, Anxiety, and Depression in Laboratory Rats.

    PubMed

    Aydin, Emel; Hritcu, Lucian; Dogan, Gulden; Hayta, Sukru; Bagci, Eyup

    2016-11-01

    In the present study, we identified the effects of inhaled Pimpinella peregrina essential oil (1 and 3 %, for 21 continuous days) on scopolamine-induced memory impairment, anxiety, and depression in laboratory rats. Y-maze and radial arm-maze tests were used for assessing memory processes. Also, the anxiety and depressive responses were studied by means of the elevated plus-maze and forced swimming tests. The scopolamine alone-treated rats exhibited the following: decrease of the spontaneous alternation percentage in Y-maze test, increase of the number of working and reference memory errors in radial arm-maze test, along with decrease of the exploratory activity, the percentage of the time spent and the number of entries in the open arm within elevated plus-maze test and decrease of swimming time and increase of immobility time within forced swimming test. Inhalation of the P. peregrina essential oil significantly improved memory formation and exhibited anxiolytic- and antidepressant-like effects in scopolamine-treated rats. Our results suggest that the P. peregrina essential oil inhalation ameliorates scopolamine-induced memory impairment, anxiety, and depression. Moreover, studies on the P. peregrina essential oil may open a new therapeutic window for the prevention of neurological abnormalities closely related to Alzheimer's disease.

  9. The Ameliorating Effect of Myrrh on Scopolamine-Induced Memory Impairments in Mice

    PubMed Central

    Baral, Samrat; Cho, Du-Hyong; Pariyar, Ramesh; Yoon, Chi-Su; Chang, Bo-yoon; Kim, Dae-Sung; Cho, Hyoung-Kwon; Kim, Sung Yeon; Oh, Hyuncheol; Kim, Youn-Chul; Kim, Jaehyo; Seo, Jungwon

    2015-01-01

    Myrrh has been used since ancient times for the treatment of various diseases such as inflammatory diseases, gynecological diseases, and hemiplegia. In the present study, we investigated the effects of aqueous extracts of myrrh resin (AEM) on scopolamine-induced memory impairments in mice. AEM was estimated with (2E,5E)-6-hydroxy-2,6-dimethylhepta-2,4-dienal as a representative constituent by HPLC. The oral administration of AEM for 7 days significantly reversed scopolamine-induced reduction of spontaneous alternation in the Y-maze test. In the passive avoidance task, AEM also restored the decreased latency time of the retention trial by scopolamine treatment. In addition, Western blot analysis and Immunohistochemistry revealed that AEM reversed scopolamine-decreased phosphorylation of Akt and extracellular signal-regulated kinase (ERK). Our study demonstrates for the first time that AEM ameliorates the scopolamine-induced memory impairments in mice and increases the phosphorylation of Akt and ERK in the hippocampus of mice brain. These results suggest that AEM has the therapeutic potential in memory impairments. PMID:26635888

  10. Modulation of adenosine signaling prevents scopolamine-induced cognitive impairment in zebrafish.

    PubMed

    Bortolotto, Josiane Woutheres; Melo, Gabriela Madalena de; Cognato, Giana de Paula; Vianna, Mônica Ryff Moreira; Bonan, Carla Denise

    2015-02-01

    Adenosine, a purine ribonucleoside, exhibits neuromodulatory and neuroprotective effects in the brain and is involved in memory formation and cognitive function. Adenosine signaling is mediated by adenosine receptors (A1, A2A, A2B, and A3); in turn, nucleotide and nucleoside-metabolizing enzymes and adenosine transporters regulate its levels. Scopolamine, a muscarinic cholinergic receptor antagonist, has profound amnesic effects in a variety of learning paradigms and has been used to induce cognitive deficits in animal models. This study investigated the effects of acute exposure to caffeine (a non-selective antagonist of adenosine receptors A1 and A2A), ZM 241385 (adenosine receptor A2A antagonist), DPCPX (adenosine receptor A1 antagonist), dipyridamole (inhibitor of nucleoside transporters) and EHNA (inhibitor of adenosine deaminase) in a model of pharmacological cognitive impairment induced by scopolamine in adult zebrafish. Caffeine, ZM 241385, DPCPX, dipyridamole, and EHNA were acutely administered independently via i.p. in zebrafish, followed by exposure to scopolamine dissolved in tank water (200μM). These compounds prevented the scopolamine-induced amnesia without impacting locomotor activity or social interaction. Together, these data support the hypothesis that adenosine signaling may modulate memory processing, suggesting that these compounds present a potential preventive strategy against cognitive impairment.

  11. Cognitive enhancing effect of the fermented Gumiganghwal-tang on scopolamine-induced memory impairment in mice.

    PubMed

    Weon, Jin Bae; Lee, Jiwoo; Eom, Min Rye; Jung, Youn Sik; Ma, Choong Je

    2016-01-01

    Gumiganghwal-tang (GT) is a traditional herbal medicine that is widely used for its anti-inflammatory, analgesic, and antipyretic actions. Fermented GT has been reported to inhibit acetylcholinesterase (AChE) activity and to exert a neuroprotective effect. In this study, we investigated the effect of fermented GT against scopolamine-induced memory impairment in mice using the Morris water maze and passive avoidance tests. The results of the Morris water maze test indicated that fermented GT significantly decreased escape latency, as compared with that observed in the scopolamine-treated group. In the prove test, fermented GT attenuated the decreased time spent in the target quadrant observed after scopolamine treatment. The results of the passive avoidance test indicated that the treatment with fermented GT increased latency time when compared with the scopolamine-treated group. Moreover, fermented GT inhibited AChE activity in the hippocampi of the treated mice. These results suggest that fermented GT reduced scopolamine-induced amnesia in mice through AChE inhibition. Therefore, we hypothesize that fermented GT may be a useful therapeutic agent for the prevention or treatment of neurodegenerative diseases.

  12. Neuroprotective Effects of AMP-Activated Protein Kinase on Scopolamine Induced Memory Impairment

    PubMed Central

    Kim, Soo-Jeong; Lee, Jun-Ho; Chung, Hwan-Suck; Song, Joo-Hyun; Ha, Joohun

    2013-01-01

    AMP-activated protein kinase (AMPK), an important regulator of energy metabolism, is activated in response to cellular stress when intracellular levels of AMP increase. We investigated the neuroprotective effects of AMPK against scopolamine-induced memory impairment in vivo and glutamate-induced cytotoxicity in vitro. An adenovirus expressing AMPK wild type alpha subunit (WT) or a dominant negative form (DN) was injected into the hippocampus of rats using a stereotaxic apparatus. The AMPK WT-injected rats showed significant reversal of the scopolamine induced cognitive deficit as evaluated by escape latency in the Morris water maze. In addition, they showed enhanced acetylcholinesterase (AChE)-reactive neurons in the hippocampus, implying increased cholinergic activity in response to AMPK. We also studied the cellular mechanism by which AMPK protects against glutamate-induced cell death in primary cultured rat hippocampal neurons. We further demonstrated that AMPK WT-infected cells increased cell viability and reduced Annexin V positive hippocampal neurons. Western blot analysis indicated that AMPK WT-infected cells reduced the expression of Bax and had no effects on Bcl-2, which resulted in a decreased Bax/Bcl-2 ratio. These data suggest that AMPK is a useful cognitive impairment treatment target, and that its beneficial effects are mediated via the protective capacity of hippocampal neurons. PMID:23946693

  13. Lithium attenuates scopolamine-induced memory deficits with inhibition of GSK-3β and preservation of postsynaptic components.

    PubMed

    Wu, Yuan-Yuan; Wang, Xiong; Tan, Lu; Liu, Dan; Liu, Xing-Hua; Wang, Qun; Wang, Jian-Zhi; Zhu, Ling-Qiang

    2013-01-01

    Cholinergic dysfunction plays a crucial role in the memory deterioration of Alzheimer's disease, but the molecular mechanism is not fully understood. By employing a widely recognized cholinergic dysfunction rat model that was produced by intraperitoneal injection of scopolamine, we investigated the mechanisms underlying scopolamine-induced memory deficits. We found that scopolamine caused spatial learning and memory deficits that involved activation of glycogen synthase kinase-3β (GSK-3β) and impairments of dendrite arborization and spine formation/maturation associated with alterations of AMPAR, Homer1, and CREB. Pretreatment by intraperitoneal injection of lithium, an inhibitor of GSK-3, for one week prevented the synaptic changes and the learning and memory deficits induced by scopolamine. Lithium treatment also activated cholineacetyltransferase and inhibited acetylcholinesterase, which might have also contributed to the improved memory. Our findings suggest that GSK-3β may be a key molecular mediator of cholinergic synaptic dysfunction, and that inhibition of GSK-3β by lithium may be promising in protecting cholinergic synaptic functions.

  14. Beneficial effect of commercial Rhodiola extract in rats with scopolamine-induced memory impairment on active avoidance.

    PubMed

    Vasileva, Liliya V; Getova, Damianka P; Doncheva, Nina D; Marchev, Andrey S; Georgiev, Milen I

    2016-12-04

    Rhodiola rosea L., family Crassulaceae also known as Golden Root or Arctic root is one of the most widely used medicinal plants with effect on cognitive dysfunction, psychological stress and depression. The aim of the study was to examine the effect of a standardized commercial Rhodiola extract on learning and memory processes in naive rats as well as its effects in rats with scopolamine-induced memory impairment.

  15. Gongjin-Dan Enhances Hippocampal Memory in a Mouse Model of Scopolamine-Induced Amnesia

    PubMed Central

    Lee, Jin-Seok; Hong, Sung-Shin; Kim, Hyeong-Geug; Lee, Hye-Won; Kim, Won-Yong; Lee, Sam-Keun; Son, Chang-Gue

    2016-01-01

    We evaluated the neuropharmacological effects of Gongjin-Dan (GJD) on the memory impairment caused by scopolamine injection. BALB/c mice were orally treated with GJD (100, 200, or 400 mg/kg, daily) or tacrine (THA, 10 mg/kg) for 10 days, and scopolamine (2 mg/kg) was injected intraperitoneally. The radial arm maze and passive avoidance tests were performed to evaluate the animal’s learning and memory. Scopolamine increased the task completing time, the number of total errors (reference and working memory error) in the radial arm maze task, and the latency time in the passive avoidance test, which were significantly ameliorated by treatment with GJD. The GJD treatment also attenuated the scopolamine-induced hyperactivation of acetylcholinesterase activity, and suppression of the expression of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF) and their receptors in the hippocampus. These effects of GJD were supported by both the doublecortin (DCX)-positive staining and Nissl staining, which were used to measure hippocampal neurogenesis and atrophy, respectively. These findings strongly suggest that GJD exerts a potent anti-amnesic effect, and its underlying mechanism might involve the modulation of cholinergic activity. PMID:27483466

  16. Effects of vitexin on scopolamine-induced memory impairment in rats.

    PubMed

    Abbasi, Esmail; Nassiri-Asl, Marjan; Sheikhi, Mehdi; Shafiee, Mahsa

    2013-06-30

    Various synthetic derivatives of natural flavonoids are known to have neuroactive properties. The present study aimed to investigate the effects of vitexin (5, 7, 4-trihydroxyflavone-8-glucoside), a flavonoid found in such plants as tartary buckwheat sprouts, wheat leaves phenolome, Mimosa pudica Linn and Passiflora spp, on scopolamine-induced memory impairment in rats. To achieve this goal, we assessed the effects of vitexin on memory retrieval in the presence or absence of scopolamine using a step-through passive avoidance trial. In the first part of the study, vitexin (25, 50, and 100 microM) was administered intracerebroventricularly (i.c.v.) before acquisition trials. In the second part, vitexin, at the same doses, was administered before scopolamine (10 microg, i.c.v.) and before the acquisition trials. During retention tests, vitexin (100 microM) in the absence of scopolamine significantly increased the step-through latencies compared to scopolamine. In addition, vitexin (100 microM) significantly reversed the shorter step-through latencies induced by scopolamine (P < 0.05). These results indicate that vitexin has a potential role in enhancing memory retrieval. A possible mechanism is modulation of cholinergic receptors; however, other mechanisms may be involved in its effects in acute exposure.

  17. Secreted calmodulin-like skin protein ameliorates scopolamine-induced memory impairment.

    PubMed

    Hayashi, Masaaki; Tajima, Hirohisa; Hashimoto, Yuichi; Matsuoka, Masaaki

    2014-06-18

    Humanin, a short bioactive peptide, inhibits cell death in a variety of cell-based death models through Humanin receptors in vitro. In vivo, Humanin ameliorates both muscarinic receptor antagonist-induced memory impairment in normal mice and memory impairment in Alzheimer's disease (AD)-relevant mouse models including aged transgenic mice expressing a familial AD-linked gene. Recently, calmodulin-like skin protein (CLSP) has been shown to be secreted from skin tissues, contain a region minimally similar to the core region of Humanin, and inhibit AD-related neuronal death through the heterotrimeric Humanin receptor on the cell surface in vitro. As CLSP is much more potent than Humanin and efficiently transported through blood circulation across the blood-brain barrier to the central nervous system, CLSP is considered as a physiological agonist that binds to the heterotrimeric Humanin receptor and triggers the Humanin-induced signals in central nervous system. However, it remains unknown whether CLSP ameliorates memory impairment in mouse dementia models as Humanin does. In this study, we show that recombinant CLSP, administered intracerebroventricularly or intraperitoneally, ameliorates scopolamine-induced dementia in mice.

  18. Antiamnesic activity of Syzygium cumini against scopolamine induced spatial memory impairments in rats.

    PubMed

    Alikatte, Kanaka Latha; Akondi, Butchi Raju; Yerragunta, Venu Gopal; Veerareddy, Prabhakar Reddy; Palle, Suresh

    2012-11-01

    We evaluated the Antiamnesic effects of methanolic extract of Syzygium cumini (MESC) on spatial memory impairments induced by scopolamine (1 mg/kg, i.p.), a muscarinic antagonist, using the Radial arm maze, Morris water maze, learned helpless ness tests. Effect of MESC was evaluated and compared to standard drug, piracetam (200 mg/kg, i.p.). The MESC significantly (p<0.05) improved the impairment of short term or working memory induced by scopolamine in the Radial arm maze test, and significantly (p<0.05) reversed cognitive impairments in rats as measured by the learned helplessness test. In addition, MESC decreased escape latencies in the Morris water maze test. The activity of acetylcholinesterase in the brain was inhibited significantly (p<0.05) by treatment with MESC to a level similar to that observed in rats treated with piracetam. Moreover treatment with MESC (200 and 400 mg/kg, p.o.) to scopolamine induced rats significantly (p<0.05) decreased TBARS levels which was accompanied by an increase in the activities of SOD and Catalase. MESC has dose dependent effect and 400 mg/kg dose shown more prominent results when compared to 200 mg/kg dose of MESC. These results indicate that MESC may exert anti-amnesic activity via inhibition of acetylcholinesterase and antioxidant mechanisms in the brain.

  19. Ameliorative effect of rosmarinic acid on scopolamine-induced memory impairment in rats.

    PubMed

    Hasanein, Parisa; Mahtaj, Azam Kazemian

    2015-01-12

    Rosmarinic acid (RA) is a natural phenol that exerts different biological activities, such as antioxidant activity and neuroprotective effects. In this study, we hypothesized that administration of RA (8, 16, and 32 mg/kg, p.o.) for 7 days would effect on scopolamine-induced cognitive dysfunction as an extensively used model of cognitive impairment. The rats were divided into 10 groups. The acquisition trial was done 1h after the last administration of RA. Animals were divided into control, RA (8, 16, and 32 mg/kg) and donepezil (2 mg/kg) treated controls, scopolamine, RA (8, 16, and 32 mg/kg), and donepezil (2 mg/kg) treated scopolamine groups. Memory impairment was induced by scopolamine treatment (1 mg/kg, i.p.) 30 min after the administration of RA, donepezil, or saline. Scopolamine administration caused cognition deficits in the PAL and memory paradigm. While orally RA administration (16 and 32 mg/kg) improved learning and memory in control rats, it reversed learning and memory deficits of scopolamine received groups. Administration of RA at the dose of 8 mg/kg did not alter cognitive function in control and scopolamine treated groups. The combination of anticholinesterase, neuroprotective, and antioxidant properties of RA may all be responsible for the observed effects. These results indicate the beneficial effects of subchronic RA administration in passive avoidance learning and memory in control rats as well as in a pharmacological model of cholinergic deficit which continue to expand the knowledge base in creating new treatment strategies for cognition deficits and dementia. Of course, further studies are warranted for clinical use of RA in the management of demented subjects.

  20. Scopolamine-induced deficits in social memory in mice: reversal by donepezil.

    PubMed

    Riedel, G; Kang, S H; Choi, D Y; Platt, B

    2009-12-01

    Deficits in social behaviour is a characteristic of numerous mental disorders including autism, schizophrenia, depression and Alzheimer's disease. For the assessment of pharmacological and genetic experimental disease models, conventional social interaction tasks bear the uncertainty that any drug-induced abnormality of the investigator may feed back to the drug-free companion modifying its reactions. A considerable technical improvement was recently reported by Moy et al. [Moy SS, Nadler JJ, Perez A, Barbaro RP, Johns JM, Magnuson T, et al. Sociability and preference for social novelty in five inbred strains: an approach to assess autistic-like behaviours in mice. Genes Brain Behav 2004;3:287-302] in which the drug free partner is confined to a small cage and social contacts of the investigator are recorded uncontaminated of any social reactions of the stranger. Using this novel behavioural paradigm, we here show in C57Bl/6 female mice that sociability (social interaction with a stranger mouse) is not impaired after administration of the anxiolytic diazepam (0.1-1 mg/kg) or the muscarinic antagonist scopolamine hydrobromide (0.1-1 mg/kg). However, social memory tested after a short time interval was impaired by both drugs in a dose-dependent manner (diazepam: > or = 0.5mg/kg; scopolamine: > or = 0.3mg/kg). The scopolamine-induced short-term memory deficit was reversed to normal by the choline esterase inhibitor donepezil (1 mg/kg). Given this dependence of social recognition on the cholinergic system, combined with the clinical observation of reduced social contacts in dementia patients, sociability may offer a novel endpoint biomarker with translational value in experimental models of cognitive dysfunction.

  1. Antiamnesic and Antioxidants Effects of Ferulago angulata Essential Oil Against Scopolamine-Induced Memory Impairment in Laboratory Rats.

    PubMed

    Hritcu, Lucian; Bagci, Eyup; Aydin, Emel; Mihasan, Marius

    2015-09-01

    Ferulago angulata (Apiaceae) is a shrub indigenous to western Iran, Turkey and Iraq. In traditional medicine, F. angulata is recommended for treating digestive pains, hemorrhoids, snake bite, ulcers and as sedative. In the present study, the effects of inhaled F. angulata essential oil (1 and 3%, daily, for 21 days) on spatial memory performance were assessed in scopolamine-treated rats. Scopolamine-induced memory impairments were observed, as measured by the Y-maze and radial arm-maze tasks. Decreased activities of superoxide dismutase, glutathione peroxidase and catalase along with increase of acetylcholinesterase activity and decrease of total content of reduced glutathione were observed in the rat hippocampal homogenates of scopolamine-treated animals as compared with control. Production of protein carbonyl and malondialdehyde significantly increased in the rat hippocampal homogenates of scopolamine-treated animals as compared with control, as a consequence of impaired antioxidant enzymes activities. Additionally, in scopolamine-treated rats exposure to F. angulata essential oil significantly improved memory formation and decreased oxidative stress, suggesting memory-enhancing and antioxidant effects. Therefore, our results suggest that multiple exposures to F. angulata essential oil ameliorate scopolamine-induced spatial memory impairment by attenuation of the oxidative stress in the rat hippocampus.

  2. Aqueous and hydroalcoholic extracts of Black Maca (Lepidium meyenii) improve scopolamine-induced memory impairment in mice.

    PubMed

    Rubio, Julio; Dang, Haixia; Gong, Mengjuan; Liu, Xinmin; Chen, Shi-Lin; Gonzales, Gustavo F

    2007-10-01

    Lepidium meyenii Walp. (Brassicaceae), known as Maca, is a Peruvian hypocotyl growing exclusively between 4,000 and 4,500 m altitude in the central Peruvian Andes, particularly in Junin plateau. Previously, Black variety of Maca showed to be more beneficial than other varieties of Maca on learning and memory in ovariectomized mice on the water finding test. The present study aimed to test two different doses of aqueous (0.50 and 2.00 g/kg) and hydroalcoholic (0.25 and 1.00 g/kg) extracts of Black Maca administered for 35 days on memory impairment induced by scopolamine (1mg/kg body weight i.p.) in male mice. Memory and learning were evaluated using the water Morris maze and the step-down avoidance test. Brain acetylcholinesterase (AChE) and monoamine oxidase (MAO) activities in brain were also determined. Both extracts of Black Maca significantly ameliorated the scopolamine-induced memory impairment as measured in both the water Morris maze and the step-down avoidance tests. Black Maca extracts inhibited AChE activity, whereas MAO activity was not affected. These results indicate that Black Maca improves scopolamine-induced memory deficits.

  3. P7C3 Attenuates the Scopolamine-Induced Memory Impairments in C57BL/6J Mice.

    PubMed

    Jiang, Bo; Song, Lu; Huang, Chao; Zhang, Wei

    2016-05-01

    Memory impairment is the most common symptom in patients with Alzheimer's disease. The purpose of this study is to evaluate the memory enhancing effects of P7C3, a recently identified compound with robust proneurogenic and neuroprotective effects, on the cognitive impairment induced by scopolamine, a muscarinic acetylcholine receptor antagonist. Different behavior tests including the Y-maze, Morris water maze, and passive avoidance tests were performed to measure cognitive functions. Scopolamine significantly decreased the spontaneous alternation and step-through latency of C57BL/6J mice in Y-maze test and passive avoidance test, whereas increased the time of mice spent to find the hidden platform in Morris water maze test. Importantly, intraperitoneal administration of P7C3 effectively reversed those Scopolamine-induced cognitive impairments in C57BL/6J mice. Furthermore, P7C3 treatment significantly enhanced the level of brain-derived neurotrophic factor (BDNF) signaling pathway in the cortex and hippocampus, and the usage of selective BDNF signaling inhibitor fully blocked the anti-amnesic effects of P7C3. Therefore, these findings suggest that P7C3 could improve the scopolamine-induced learning and memory impairment possibly through activation of BDNF signaling pathway, thereby exhibiting a cognition-enhancing potential.

  4. N-palmitoyl serotonin alleviates scopolamine-induced memory impairment via regulation of cholinergic and antioxidant systems, and expression of BDNF and p-CREB in mice.

    PubMed

    Min, A Young; Doo, Choon Nan; Son, Eun Jung; Sung, Nak Yun; Lee, Kun Jong; Sok, Dai-Eun; Kim, Mee Ree

    2015-12-05

    N-Palmitoyl-5-hydroxytryptamines (Pal-5HT), a cannabinoid, has recently been reported to express anti-allergic and anti-inflammatory actions in RBL-2H3 cells, and ameliorate glutamate-induced cytotoxicity in HT-22 cells. In this study, we examined the effect of Pal-5HT on deficits of learning and memory induced by scopolamine in mice. Memory performance was evaluated using Morris water maze test and passive avoidance test. Activities of acetylcholinesterase (AChE) and choline acetyltransferase (ChAT), level of oxidative stress markers, and expression of brain-derived neurotrophic factor (BDNF), phosphorylation of cAMP response element-binding protein (p-CREB) were determined. Loss of neuronal cells in hippocampus was evaluated by histological examinations. Pal-5HT significantly improved the amnesia in the behavioral assessment. Pal-5HT regulated cholinergic function by inhibiting scopolamine-induced elevation of AChE activity and decline of ChAT activity. Pal-5HT suppressed oxidative stress by increasing activities of glutathione peroxidase (GPx), glutathione reductase (GR) or NAD(P)H quinine oxidoreductase-1 (NQO-1) and lowering MDA level. Additionally, it prevented against scopolamine-induced expression of iNOS and COX-2. Moreover, Pal-5HT suppressed the death of neuronal cells in CA1 and CA3 regions, while it restored expression of p-CREB and BDNF in hippocampus. Taken together, Pal-5HT is suggested to ameliorate deficits of memory and learning through regulation of cholinergic function, activation of antioxidant systems as well as restoration of BDNF and p-CREB expression. From these, Pal-5HT may be a potential candidate to prevent against neurodegeneration related to the memory deficit.

  5. Agmatine, a metabolite of L-arginine, reverses scopolamine-induced learning and memory impairment in rats.

    PubMed

    Utkan, Tijen; Gocmez, Semil S; Regunathan, Soundararajan; Aricioglu, Feyza

    2012-10-01

    Agmatine (l-amino-4-guanidino-butane), a metabolite of L-arginine through the action of arginine decarboxylase, is a novel neurotransmitter. In the present study, effects of agmatine on cognitive functions have been evaluated by using one trial step-down passive avoidance and three panel runway task. Agmatine (20, 40, 80 mg/kg i.p.) was administered either in the presence or absence of a cholinergic antagonist, scopolamine (1 mg/kg i.p.). Scopolamine significantly impaired learning and memory in both passive avoidance and three panel runway test. Agmatine did not affect emotional learning, working and reference memory but significantly improved scopolamine-induced impairment of learning and memory in a dose dependent manner. Our results indicate that agmatine, as an endogenous substance, may have an important role in modulation of learning and memory functions.

  6. The Ameliorating Effect of Steamed and Fermented Codonopsis lanceolata on Scopolamine-Induced Memory Impairment in Mice

    PubMed Central

    Weon, Jin Bae; Yun, Bo-Ra; Lee, Jiwoo; Eom, Min Rye; Kim, Ji Seon; Lee, Hyeon Yong; Park, Dong-Sik; Chung, Hee-Chul; Chung, Jae Youn; Ma, Choong Je

    2013-01-01

    Codonopsis lanceolata (Campanulaceae) have been traditionally used to treat lung inflammatory diseases, such as asthma, tonsillitis, and pharyngitis. The present study was performed to evaluate the cognitive-enhancing effects of steamed and fermented C. lanceolata in scopolamine-induced memory impairments in mice. Cognitive abilities were determined by the Morris water maze and passive avoidance tests. Mice orally received fermented C. lanceolata extract at doses of 100, 300, or 500 mg/kg body weight. Fermented C. lanceolata extract (500 mg/kg body weight, p.o.) significantly shortened the escape latency times that were increased by scopolamine on the 4th day of trial sessions in the Morris water maze task. In addition, it exerted longer step-through latency times than those of the scopolamine-treated group in the passive avoidance test. Furthermore, the neuroprotective effects of fermented C. lanceolata extract on glutamate-induced neurocytotoxicity were investigated in HT22 cells. Fermented C. lanceolata extract showed a relative protection ratio of 59.62% at 500 μg/mL. In conclusion, fermented C. lanceolata extract ameliorated scopolamine-induced memory impairments, exerted neuroprotective effects, and improved activity compared to that found with original C. lanceolata. Further study will be required to investigate the mechanisms underlying this cognitive-enhancing activity. PMID:23935665

  7. Hippocampal chromatin-modifying enzymes are pivotal for scopolamine-induced synaptic plasticity gene expression changes and memory impairment.

    PubMed

    Singh, Padmanabh; Konar, Arpita; Kumar, Ashish; Srivas, Sweta; Thakur, Mahendra K

    2015-08-01

    The amnesic potential of scopolamine is well manifested through synaptic plasticity gene expression changes and behavioral paradigms of memory impairment. However, the underlying mechanism remains obscure and consequently ideal therapeutic target is lacking. In this context, chromatin-modifying enzymes, which regulate memory gene expression changes, deserve major attention. Therefore, we analyzed the expression of chromatin-modifying enzymes and recovery potential of enzyme modulators in scopolamine-induced amnesia. Scopolamine administration drastically up-regulated DNA methyltransferases (DNMT1) and HDAC2 expression while CREB-binding protein (CBP), DNMT3a and DNMT3b remained unaffected. HDAC inhibitor sodium butyrate and DNMT inhibitor Aza-2'deoxycytidine recovered scopolamine-impaired hippocampal-dependent memory consolidation with concomitant increase in the expression of synaptic plasticity genes Brain-derived neurotrophic factor (BDNF) and Arc and level of histone H3K9 and H3K14 acetylation and decrease in DNA methylation level. Sodium butyrate showed more pronounced effect than Aza-2'deoxycytidine and their co-administration did not exhibit synergistic effect on gene expression. Taken together, we showed for the first time that scopolamine-induced up-regulation of chromatin-modifying enzymes, HDAC2 and DNMT1, leads to gene expression changes and consequent decline in memory consolidation. Our findings on the action of scopolamine as an epigenetic modulator can pave a path for ideal therapeutic targets. We propose the following putative pathway for scopolamine-mediated memory impairment; scopolamine up-regulates hippocampal DNMT1 and HDAC2 expression, induces methylation and deacetylation of BDNF and Arc promoter, represses gene expression and eventually impairs memory consolidation. On the other hand, Aza-2 and NaB inhibit DNMT1 and HDAC2 respectively, up-regulate BDNF and Arc expression and recover memory consolidation. We elucidate the action of

  8. Protective effects of aloe-emodin on scopolamine-induced memory impairment in mice and H₂O₂-induced cytotoxicity in PC12 cells.

    PubMed

    Tao, Li; Xie, Jianmei; Wang, Yuting; Wang, Shi; Wu, Shuangchan; Wang, Qiman; Ding, Hong

    2014-12-01

    Aloe-emodin (AE) is one of the most important active components of Rheum officinale Baill. The present study aimed to investigate that AE could attenuate scopolamine-induced cognitive deficits via inhibiting acetylcholinesterase (AChE) activity and modulating oxidative stress. Kunming (KM) mice were received intraperitoneal injection of scopolamine (2 mg/kg) to induce cognitive impairment. Learning and memory performance were assessed in the Morris water maze (MWM). After behavioral testing, the mice were sacrificed and their hippocampi were removed for biochemical assays (superoxide dismutase (SOD), glutathione peroxidase (GPx), malondialdehyde (MDA), AChE and acetylcholine (ACh)). In vitro, we also performed the AChE activity assay and H₂O₂-induced PC12 cells toxicity assay. After 2 h exposure to 200 μM H₂O₂ in PC12 cells, the cytotoxicity were evaluated by cell viability (MTT), nitric oxide (NO)/lactate dehydrogenase (LDH) release and intracellular reactive oxygen species (ROS) production. Our results confirmed that AE showed significant improvement in cognitive deficit in scopolamine-induced amnesia animal model. Besides, it increased SOD, GPx activities and ACh content, while decreased the level of MDA and AChE activity in AE treated mice. In addition, AE was found to inhibit AChE activity (IC₅₀ = 18.37 μg/ml) in a dose-dependent manner. Furthermore, preincubation of PC12 cells with AE could prevent cytotoxicity induced by H₂O₂ and reduce significantly extracellular release of NO, LDH and intracellular accumulation of ROS. The study indicated that AE could have neuroprotective effects against Alzheimer's disease (AD) via inhibiting the activity of AChE and modulating oxidative stress.

  9. The effects of Anethum graveolens essence on scopolamine-induced memory impairment in mice.

    PubMed

    Mesripour, Azadeh; Rafieian-Kopaei, Mahmoud; Bahrami, Bahareh

    2016-01-01

    Since Anethum graveolens (Dill) has phytoestrogenic compounds and it is proven that estrogens exert beneficial effects on cognition; the aim of this study was to understand if this plant can improve memory performance. Male Balb/c mice weighing 25-30 g were used in this study and memory was assessed by the novel object recognition task. In this method, the difference in the exploration time between a familiar object and a novel object is taken as an index of memory performance (recognition index, RI). Scopolamine significantly reduced memory index (RI = -15.5% ± 3.0). Dill essence (100 mg/kg, ip) prevented the harmful effects of scopolamine on memory (RI = 40% ± 5.5), thus RI did not differ with control animals (RI = 50% ± 5.8). In addition, 17-β estradiol also prevented memory impairment in animals (0.2 mg/kg, ip; RI = 35.8% ± 6.5). Nevertheless, the beneficial effects of dill essence were antagonized by prior injection of tamoxifen (1 mg/kg, ip; RI = -30% ± 7.8). Although phytoesrogens are not steroids, the beneficial effect of dill on memory, at least in part, may have been achieved by estrogenic receptors present in the brain. Thus dill essence could be promising in improving memory and cognition, mainly in postmenopausal women.

  10. The effects of Anethum graveolens essence on scopolamine-induced memory impairment in mice

    PubMed Central

    Mesripour, Azadeh; Rafieian-Kopaei, Mahmoud; Bahrami, Bahareh

    2016-01-01

    Since Anethum graveolens (Dill) has phytoestrogenic compounds and it is proven that estrogens exert beneficial effects on cognition; the aim of this study was to understand if this plant can improve memory performance. Male Balb/c mice weighing 25-30 g were used in this study and memory was assessed by the novel object recognition task. In this method, the difference in the exploration time between a familiar object and a novel object is taken as an index of memory performance (recognition index, RI). Scopolamine significantly reduced memory index (RI = -15.5% ± 3.0). Dill essence (100 mg/kg, ip) prevented the harmful effects of scopolamine on memory (RI = 40% ± 5.5), thus RI did not differ with control animals (RI = 50% ± 5.8). In addition, 17-β estradiol also prevented memory impairment in animals (0.2 mg/kg, ip; RI = 35.8% ± 6.5). Nevertheless, the beneficial effects of dill essence were antagonized by prior injection of tamoxifen (1 mg/kg, ip; RI = -30% ± 7.8). Although phytoesrogens are not steroids, the beneficial effect of dill on memory, at least in part, may have been achieved by estrogenic receptors present in the brain. Thus dill essence could be promising in improving memory and cognition, mainly in postmenopausal women. PMID:27168754

  11. Inhibition of central angiotensin converting enzyme ameliorates scopolamine induced memory impairment in mice: role of cholinergic neurotransmission, cerebral blood flow and brain energy metabolism.

    PubMed

    Tota, Santoshkumar; Nath, Chandishwar; Najmi, Abul Kalam; Shukla, Rakesh; Hanif, Kashif

    2012-06-15

    Evidences indicate that inhibition of central Renin angiotensin system (RAS) ameliorates memory impairment in animals and humans. Earlier we have reported involvement of central angiotensin converting enzyme (ACE) in streptozotocin induced neurodegeneration and memory impairment. The present study investigated the role of central ACE in cholinergic neurotransmission, brain energy metabolism and cerebral blood flow (CBF) in model of memory impairment induced by injection of scopolamine in mice. Perindopril (0.05 and 0.1 mg/kg, PO) was given orally for one week before administration of scopolamine (3mg/kg, IP). Then, memory function was evaluated by Morris water maze and passive avoidance tests. CBF was measured by laser Doppler flowmetry. Biochemical and molecular parameters were estimated after the completion of behavioral studies. Scopolamine caused impairment in memory which was associated with reduced CBF, acetylcholine (ACh) level and elevated acetylcholinesterase (AChE) activity and malondialdehyde (MDA) level. Perindopril ameliorated scopolamine induced amnesia in both the behavioral paradigms. Further, perindopril prevented elevation of AChE and MDA level in mice brain. There was a significant increase in CBF and ACh level in perindopril treated mice. However, scopolamine had no significant effect on ATP level and mRNA expression of angiotensin receptors and ACE in cortex and hippocampus. But, perindopril significantly decreased ACE activity in brain without affecting its mRNA expression. The study clearly showed the interaction between ACE and cholinergic neurotransmission and beneficial effect of perindopril can be attributed to improvement in central cholinergic neurotransmission and CBF.

  12. A comparative study of neuroprotective effect of angiotensin converting enzyme inhibitors against scopolamine-induced memory impairments in rats

    PubMed Central

    Jawaid, Talha; Jahan, Shah; Kamal, Mehnaz

    2015-01-01

    The comparative study of neuroprotective effect of angiotensin converting enzyme inhibitors against scopolamine-induced neuroinflammation in albino Wistar rats was studied. Male albino rats were administered with scopolamine to induce memory impairment. The standard nootropic agent, piracetam (200 mg/kg b.w., [i.p.]), perindopril (0.1 mg/kg b.w., [i.p.]), enalapril (0.1 mg/kg b.w., [i.p.]), and ramipril (0.1 mg/kg b.w., [i.p.]) were administered in different group of animals for 5 days. On 5th day, scopolamine (1 mg/kg b.w., i.p.) was administered after 60 min of the last dose of test drug. Memory function was evaluated in Morris water maze (MWM) test and pole climbing test (PCT). Biochemical estimations like glutathione (GSH), malondialdehyde (MDA), and acetylcholinesterase activity in the brain were estimated after completion of behavior study. All three test groups shows improvement in learning and memory in comparison to control group. Perindopril treated group showed a more effective significant decrease in escape latency time and transfer latency time compared to enalapril and ramipril treated group on day 4 in MWM test and PCT, respectively. Perindopril shows a significant reduction in MDA level and acetylcholinesterase activity and a significant rise in GSH level compared to enalapril and ramipril. The finding of this study indicates that Perindopril is more effective in memory retention compared to enalapril and ramipril. PMID:26317078

  13. Anti-amnesic activity of Citrus aurantium flowers extract against scopolamine-induced memory impairments in rats.

    PubMed

    Rahnama, Samira; Rabiei, Zahra; Alibabaei, Zahra; Mokhtari, Shiva; Rafieian-Kopaei, Mahmoud; Deris, Fatemeh

    2015-04-01

    Alzheimer's disease (AD) is a progressive neurological disorder that mostly affects the elderly population. Learning and memory impairment as the most characteristic manifestation of dementia could be induced chemically by scopolamine, a cholinergic antagonist. Cholinergic neurotransmission mediated brain oxidative stress. Citrus aurantium (CA) has traditionally been used for the treatment of insomnia, anxiety and epilepsy. The present study was designed to investigate the effect of Citrus aurantium on scopolamine-induced learning and memory deficit in rats. Forty-two Wistar rats were divided into six equal groups. (1) Control (received saline), (2) SCOP (scopolamine at a dose of 1 mg/kg for 15 days), (3) and (4) SCOP + CA (scopolamine and CA extract at doses of 300 and 600 mg/kg per day for 15 days), (5) and (6) intact groups (CA extract at 300 and 600 mg/kg per day for 15 days, respectively). Administration of CA flower extract significantly restored memory and learning impairments induced by scopolamine in the passive avoidance test and also reduced escape latency during trial sessions in the Morris water maze test. Citrus aurantium flower extract significantly decreased the serum malondialdehyde (MDA) levels. Citrus aurantium flower extract has repairing effects on memory and behavioral disorders produced by scopolamine and may have beneficial effects in the treatment of AD.

  14. Melatonin attenuates scopolamine-induced memory/synaptic disorder by rescuing EPACs/miR-124/Egr1 pathway.

    PubMed

    Wang, Xiong; Wang, Zhi-Hao; Wu, Yuan-Yuan; Tang, Hui; Tan, Lu; Wang, Xiang; Gao, Xin-Ya; Xiong, Yan-Si; Liu, Dan; Wang, Jian-Zhi; Zhu, Ling-Qiang

    2013-02-01

    Alzheimer's disease (AD) is the most prevalent type of dementia in elderly people. There are decreased melatonin levels in the serum of AD patients, and melatonin supplements are able to reverse AD pathology and memory deficits in many animal experiments and clinical trials. However, the underlying mechanism regarding how melatonin rescues the AD-like memory/synaptic disorder remains unknown. Here, we use the Morris water maze, step-down inhibitory avoidance task, in vivo long-term potentiation recording, and Golgi staining and report that intraperitoneal injection of melatonin (1 mg/kg/day) for 14 days in rats effectively reverses the memory and synaptic impairment in scopolamine-induced amnesia, a well-recognized dementia animal model. Using real-time polymerase chain reaction and western blotting experiments, we further determined that melatonin rescues the EPACs/miR-124/Egr1 signal pathway, which is important in learning and memory, as reported recently. Our studies provide a novel underlying epigenetic mechanism for melatonin to attenuate the synaptic disorder and could benefit drug discovery in neurodegenerative diseases.

  15. [Effect and mechanism of Coeloglossum viride var. bracteatum extract on scopolamine-induced deficits of learning and memory behavior of rodents].

    PubMed

    Li, Min; Wang, Ya-fang; Ma, Bo; Liu, Geng-tao; Zhang, Jian-jun

    2009-05-01

    The aim of the present study is to investigate the effect and mechanism of Coeloglossum viride var. bracteatum extract (CE) on scopolamine-induced learning and memory deficits. Learning and memory deficits of mice were evaluated by step-down passive avoidance test. Long-term potentiation of rats was detected in the dentate gyrus of hippocampus. Brain acetylcholinesterase (AChE) and choline acetyltransferase (ChAT) activities were also determined. The results showed that scopolamine impaired learning and memory performance and LTP induction in hippocampus. Oral administration of CE (5, 10, and 20 mg x kg(-1)) significantly alleviated scopolamine-induced memory deficits measured by step-down test (P < 0.05). CE (5 mg x kg(-1), ip) significantly reversed the inhibitory effect of scopolamine on LTP in rats. In addition, CE was found to increase the activity of ChAT in rat brain. These results suggested that CE could alleviate scopolamine-induced learning and memory deficits, which might be due to the LTP-improvement and ChAT activity enhancement.

  16. Effects of Fructus Akebiae on learning and memory impairment in a scopolamine-induced animal model of dementia

    PubMed Central

    WANG, JINGHUA; WANG, XUAN; LV, BAOSHENG; YUAN, WEIXIU; FENG, ZEGUO; MI, WEIDONG; ZHANG, HONG

    2014-01-01

    Fructus Akebiae (FAE) is a component of traditional Chinese medicines used for the clinical treatment of amnesia. The aim of the present study was to investigate the effects of FAE extract on scopolamine-induced learning and memory impairment in mice and Sprague-Dawley rats. Treatment with FAE (2.5, 5 and 10 mg/kg) was investigated in scopolamine-treated animals, and its effects on different types of memory were examined using the T-maze, the Morris water maze task, the novel object recognition test, the passive avoidance task and the step-down test. The results revealed that 5 and 10 mg/kg FAE attenuated scopolamine-mediated impairment of cognition, including spatial, episodic, aversive, and short- and long-term memory. Overall, these results suggest that FAE is an effective cognitive enhancer, and thus highlights the value of a multi-target strategy to address the complexity of cognitive dysfunction in Alzheimer’s disease. PMID:25009638

  17. Neuroprotective and Antiamnesic Effects of Mitragyna inermis Willd (Rubiaceae) on Scopolamine-Induced Memory Impairment in Mice

    PubMed Central

    Bum, Elisabeth Ngo; Taïwé, Germain Sotoing; Ngoupaye, Gwladys Temkou; Sidiki, Neteydji; Moto, Fleur Clarisse Okomolo; Kouemou, Nadège; Njapdounke, Stephanie Jacqueline Kameni; Nkantchoua, Gisele; Omam, Jean Pierre Omam; Mairaira, Veronique

    2017-01-01

    Aim. To assess memory improvement and neuroprotective and antioxidant effects of Mitragyna inermis (M. inermis) leaf decoction on the central nervous system. Methodology. Leaf decoction of M. inermis was tested on learning and memory in normal and scopolamine-induced cognitive impairment in mice using memory behavioral tests such as the Morris water maze, object recognition task, and elevated plus maze. Oxidative stress enzymes—catalase, superoxide dismutase, and the thiobarbituric acid reactive substance, a product of lipid peroxidation—were quantified. In each test, mice 18 to 25 g were divided into groups of 5. Results. The extract reversed the effects of scopolamine in mice. The extract significantly increased discrimination index in the object recognition task test and inflexion ratio in the elevated plus maze test. The times spent in target quadrant in MWM increased while the transfer latency decreased in mice treated by M. inermis at the dose of 196.5 mg/kg. The activity levels of superoxide dismutase and catalase were significantly increased, whereas the thiobarbituric acid reactive substance was significantly decreased after 8 consecutive days of treatment with M. inermis at the dose of 393 mg/kg. Conclusion. These results suggest that M. inermis leaf extract possess potential antiamnesic effects. PMID:28386162

  18. ESP-102, a standardized combined extract of Angelica gigas, Saururus chinensis and Schizandra chinensis, significantly improved scopolamine-induced memory impairment in mice.

    PubMed

    Kang, So Young; Lee, Ki Yong; Koo, Kyung Ah; Yoon, Jeong Seon; Lim, Song Won; Kim, Young Choong; Sung, Sang Hyun

    2005-02-25

    We assessed the effects of oral treatments of ESP-102, a standardized combined extract of Angelica gigas, Saururus chinensis and Schizandra chinensis, on learning and memory deficit. The cognition-enhancing effect of ESP-102 was investigated in scopolamine-induced (1 mg/kg body weight, s.c.) amnesic mice with both passive avoidance and Morris water maze performance tests. Acute oral treatment (single administration prior to scopolamine treatment) of mice with ESP-102 (doses in the range of 10 to 100 mg/kg body weight) significantly reduced scopolamine-induced memory deficits in the passive avoidance performance test. Another noteworthy result included the fact that prolonged oral daily treatments of mice with much lower amounts of ESP-102 (1 and 10 mg/kg body weight) for ten days reversed scopolamine-induced memory deficits. In the Morris water maze performance test, both acute and prolonged oral treatments with ESP-102 (single administration of 100 mg/kg body weight or prolonged daily administration of 1 and 10 mg/kg body weight for ten days, respectively, significantly ameliorated scopolamine-induced memory deficits as indicated by the formation of long-term and/or short-term spatial memory. In addition, we investigated the effects of ESP-102 on neurotoxicity induced by amyloid-beta peptide (Abeta25-35) or glutamate in primary cultured cortical neurons of rats. Pretreatment of cultures with ESP-102 (0.001, 0.01 and 0.1 mug/ml) significantly protected neurons from neurotoxicity induced by either glutamate or Abeta25-35. These results suggest that ESP-102 may have some protective characteristics against neuronal cell death and cognitive impairments often observed in Alzheimer's disease, stroke, ischemic injury and other neurodegenerative diseases.

  19. ESP-102, a Combined Herbal Extract of Angelica gigas, Saururus chinensis, and Schisandra chinensis, Changes Synaptic Plasticity and Attenuates Scopolamine-Induced Memory Impairment in Rat Hippocampus Tissue.

    PubMed

    Kim, Hyun-Bum; Hwang, Eun-Sang; Choi, Ga-Young; Lee, Seok; Park, Tae-Suk; Lee, Cheol-Won; Lee, Eun-Suk; Kim, Young-Choong; Kim, Sang Seong; Lee, Sung-Ok; Park, Ji-Ho

    2016-01-01

    ESP-102, an extract from Angelica gigas, Saururus chinensis, and Schisandra chinensis, has been used as herbal medicine and dietary supplement in Korea. Despite the numerous bioactivities in vitro and in vivo studies, its effects on neuronal networks remain elusive. To address the neuronal effect, we examined synaptic plasticity in organotypic hippocampal slice culture with multielectrode array. Our results showed an increase in excitatory postsynaptic potential (EPSP), indicating the induction of long-term potentiation (LTP), in the presence of ESP-102. In addition, the neuroprotective effect of ESP-102 was also tested by application of scopolamine to the hippocampal slice. Interestingly, ESP-102 competitively antagonized the preventative LTP effect induced by scopolamine. The scopolamine-induced reduction in brain-derived neurotrophic factor (BDNF) and GluR-2 expression was also rescued by ESP-102. In terms of mode of action, ESP-102 appears to act on the presynaptic region independent of AMPA/NMDA receptors. Based on these findings, ESP-102 can be suggested as a novel herbal ingredient with memory enhancing as well as neuroprotective effects.

  20. ESP-102, a Combined Herbal Extract of Angelica gigas, Saururus chinensis, and Schisandra chinensis, Changes Synaptic Plasticity and Attenuates Scopolamine-Induced Memory Impairment in Rat Hippocampus Tissue

    PubMed Central

    Kim, Hyun-Bum; Hwang, Eun-Sang; Choi, Ga-Young; Lee, Seok; Park, Tae-Suk; Lee, Cheol-Won; Lee, Eun-Suk; Kim, Young-Choong; Kim, Sang Seong; Lee, Sung-Ok; Park, Ji-Ho

    2016-01-01

    ESP-102, an extract from Angelica gigas, Saururus chinensis, and Schisandra chinensis, has been used as herbal medicine and dietary supplement in Korea. Despite the numerous bioactivities in vitro and in vivo studies, its effects on neuronal networks remain elusive. To address the neuronal effect, we examined synaptic plasticity in organotypic hippocampal slice culture with multielectrode array. Our results showed an increase in excitatory postsynaptic potential (EPSP), indicating the induction of long-term potentiation (LTP), in the presence of ESP-102. In addition, the neuroprotective effect of ESP-102 was also tested by application of scopolamine to the hippocampal slice. Interestingly, ESP-102 competitively antagonized the preventative LTP effect induced by scopolamine. The scopolamine-induced reduction in brain-derived neurotrophic factor (BDNF) and GluR-2 expression was also rescued by ESP-102. In terms of mode of action, ESP-102 appears to act on the presynaptic region independent of AMPA/NMDA receptors. Based on these findings, ESP-102 can be suggested as a novel herbal ingredient with memory enhancing as well as neuroprotective effects. PMID:27298627

  1. Effects of lavender oil inhalation on improving scopolamine-induced spatial memory impairment in laboratory rats.

    PubMed

    Hritcu, Lucian; Cioanca, Oana; Hancianu, Monica

    2012-04-15

    Lavender is reported to be an effective medical plant in treating inflammation, depression, stress and mild anxiety in Europe and the USA. The present study investigated the effects of two different lavender essential oils from Lavandula angustifolia ssp. angustifolia Mill. (Lamiaceae) and Lavandula hybrida Rev. (Lamiaceae) on neurological capacity of male Wistar rats subjected to scopolamine (0.7mg/kg)-induced dementia rat model. Chronic exposures to lavender essential oils (daily, for 7 continuous days) significantly reduced anxiety-like behavior and inhibited depression in elevated plus-maze and forced swimming tests, suggesting anxiolytic and antidepressant activity. Also, spatial memory performance in Y-maze and radial arm-maze tasks was improved, suggesting positive effects on memory formation. Taken together, multiple exposures to lavender essential oils could effectively reverse spatial memory deficits induced by dysfunction of the cholinergic system in the rat brain and might provide an opportunity for management neurological abnormalities in dementia conditions.

  2. D-cycloserine in Prelimbic Cortex Reverses Scopolamine-Induced Deficits in Olfactory Memory in Rats

    PubMed Central

    Portero-Tresserra, Marta; Cristóbal-Narváez, Paula; Martí-Nicolovius, Margarita; Guillazo-Blanch, Gemma; Vale-Martínez, Anna

    2013-01-01

    A significant interaction between N-methyl-D-aspartate (NMDA) and muscarinic receptors has been suggested in the modulation of learning and memory processes. The present study further investigates this issue and explores whether d-cycloserine (DCS), a partial agonist at the glycine binding site of the NMDA receptors that has been regarded as a cognitive enhancer, would reverse scopolamine (SCOP)-induced amnesia in two olfactory learning tasks when administered into the prelimbic cortex (PLC). Thus, in experiment 1, DCS (10 µg/site) was infused prior to acquisition of odor discrimination (ODT) and social transmission of food preference (STFP), which have been previously characterized as paradigms sensitive to PLC muscarinic blockade. Immediately after learning such tasks, SCOP was injected (20 µg/site) and the effects of both drugs (alone and combined) were tested in 24-h retention tests. To assess whether DCS effects may depend on the difficulty of the task, in the STFP the rats expressed their food preference either in a standard two-choice test (experiment 1) or a more challenging three-choice test (experiment 2). The results showed that bilateral intra-PLC infusions of SCOP markedly disrupted the ODT and STFP memory tests. Additionally, infusions of DCS alone into the PLC enhanced ODT but not STFP retention. However, the DCS treatment reversed SCOP-induced memory deficits in both tasks, and this effect seemed more apparent in ODT and 3-choice STFP. Such results support the interaction between the glutamatergic and the cholinergic systems in the PLC in such a way that positive modulation of the NMDA receptor/channel, through activation of the glycine binding site, may compensate dysfunction of muscarinic neurotransmission involved in stimulus-reward and relational learning tasks. PMID:23936452

  3. Brain Network Activation (BNA) reveals scopolamine-induced impairment of visual working memory.

    PubMed

    Reches, Amit; Levy-Cooperman, Naama; Laufer, Ilan; Shani-Hershkovitch, Revital; Ziv, Keren; Kerem, Dani; Gal, Noga; Stern, Yaki; Cukierman, Guy; Romach, Myroslava K; Sellers, Edward M; Geva, Amir B

    2014-09-01

    The overarching goal of this event-related potential (ERP) study was to examine the effects of scopolamine on the dynamics of brain network activation using a novel ERP network analysis method known as Brain Network Activation (BNA). BNA was used for extracting group-common stimulus-activated network patterns elicited to matching probe stimuli in the context of a delayed matching-to-sample task following placebo and scopolamine treatments administered to healthy participants. The BNA extracted networks revealed the existence of two pathophysiological mechanisms following scopolamine, disconnection, and compensation. Specifically, weaker frontal theta and parietal alpha coupling was accompanied with enhanced fronto-centro-parietal theta activation relative to placebo. In addition, using the characteristic BNA network of each treatment as well as corresponding literature-guided selective subnetworks as combined biomarkers managed to differentiate between individual responses to each of the treatments. Behavioral effects associated with scopolamine included delayed response time and impaired response accuracy. These results indicate that the BNA method is sensitive to the effects of scopolamine on working memory and that it may potentially enable diagnosis and treatment assessment of dysfunctions associated with cholinergic deficiency.

  4. Pretreatment with 5-hydroxymethyl-2-furaldehyde blocks scopolamine-induced learning deficit in contextual and spatial memory in male mice.

    PubMed

    Lee, Younghwan; Gao, Qingtao; Kim, Eunji; Lee, Younghwa; Park, Se Jin; Lee, Hyung Eun; Jang, Dae Sik; Ryu, Jong Hoon

    2015-07-01

    5-Hydroxymethyl-2-furaldehyde (5-HMF) is a compound derived from the dehydration of certain sugars. The aim of the present study was to evaluate the effect of 5-HMF on the cognitive impairment induced by scopolamine, a muscarinic receptor antagonist. To measure various cognitive functions, we conducted the step-through passive avoidance task, the Y-maze task and the Morris water maze task. A single administration of 5-HMF (5 or 10mg/kg, p.o.) significantly attenuates scopolamine-induced cognitive impairment in these behavioral tasks without changes in locomotor activity, and the effect of 5-HMF on scopolamine-induced cognitive impairment was significantly reversed by a sub-effective dose of MK-801, an NMDA receptor antagonist. In addition, a single administration of 5-HMF (10mg/kg, p.o.) enhanced the cognitive performance of normal naïve mice in the passive avoidance task. Furthermore, Western blot analysis revealed that the levels of phosphorylated Ca(2+)/calmodulin-dependent protein kinase II-α (CaMKII) and extracellular signal-regulated kinases (ERK) were significantly enhanced by the single administration of 5-HMF in the hippocampal tissues. Taken together, the present study suggests that 5-HMF may block scopolamine-induced learning deficit and enhance cognitive function via the activation of NMDA receptor signaling, including CaMKII and ERK, and would be an effective candidate against cognitive disorders, such as Alzheimer's disease.

  5. Lactobacillus casei-01 facilitates the ameliorative effects of proanthocyanidins extracted from lotus seedpod on learning and memory impairment in scopolamine-induced amnesia mice.

    PubMed

    Xiao, Juan; Li, Shuyi; Sui, Yong; Wu, Qian; Li, Xiaopeng; Xie, Bijun; Zhang, Mingwei; Sun, Zhida

    2014-01-01

    Learning and memory abilities are associated with alterations in gut function. The two-way proanthocyanidins-microbiota interaction in vivo enhances the physiological activities of proanthocyanidins and promotes the regulation of gut function. Proanthocyanidins extracted from lotus seedpod (LSPC) have shown the memory-enhancing ability. However, there has been no literature about whether Lactobacillus casei-01 (LC) enhances the ameliorative effects of LSPC on learning and memory abilities. In this study, learning and memory abilities of scopolamine-induced amnesia mice were evaluated by Y-maze test after 20-day administration of LC (10(9) cfu/kg body weight (BW)), LSPC (low dose was 60 mg/kg BW (L-LSPC) and high dose was 90 mg/kg BW (H-LSPC)), or LSPC and LC combinations (L-LSPC+LC and H-LSPC+LC). Alterations in antioxidant defense ability and oxidative damage of brain, serum and colon, and brain cholinergic system were investigated as the possible mechanisms. As a result, the error times of H-LSPC+LC group were reduced by 41.59% and 68.75% relative to those of H-LSPC and LC groups respectively. LSPC and LC combinations ameliorated scopolamine-induced memory impairment by improving total antioxidant capacity (TAOC) level, glutathione peroxidase (GSH-Px) and total superoxide dismutase (T-SOD) activities of brain, serum and colon, suppressing malondialdehyde (MDA) level of brain, serum and colon, and inhibiting brain acetylcholinesterase (AchE), myeloperoxidase, total nitric oxide synthase and neural nitric oxide synthase (nNOS) activities, and nNOS mRNA level. Moreover, LC facilitated the ameliorative effects of H-LSPC on GSH-Px activity of colon, TAOC level, GSH-Px activity and ratio of T-SOD to MDA of brain and serum, and the inhibitory effects of H-LSPC on serum MDA level, brain nNOS mRNA level and AchE activity. These results indicated that LC promoted the memory-enhancing effect of LSPC in scopolamine-induced amnesia mice.

  6. Effects of harmine, an acetylcholinesterase inhibitor, on spatial learning and memory of APP/PS1 transgenic mice and scopolamine-induced memory impairment mice.

    PubMed

    He, Dandan; Wu, Hui; Wei, Yue; Liu, Wei; Huang, Fei; Shi, Hailian; Zhang, Beibei; Wu, Xiaojun; Wang, Changhong

    2015-12-05

    Harmine, a β-carboline alkaloid present in Peganum harmala with a wide spectrum of pharmacological activities, has been shown to exert strong inhibition against acetylcholinesterase in vitro. However, whether it can rescue the impaired cognition has not been elucidated yet. In current study, we examined its effects on scopolamine-induced memory impairment mice and APP/PS1 transgenic mice, one of the models for Alzheimer's disease, using Morris Water Maze test. In addition, whether harmine could penetrate blood brain barrier, interact with and inhibit acetylcholinesterase, and activate downstream signaling network was also investigated. Our results showed that harmine (20mg/kg) administered by oral gavage for 2 weeks could effectively enhance the spatial cognition of C57BL/6 mice impaired by intraperitoneal injection of scopolamine (1mg/kg). Meanwhile, long-term consumption of harmine (20mg/kg) for 10 weeks also slightly benefited the impaired memory of APP/PS1 mice. Furthermore, harmine could pass through blood brain barrier, penetrate into the brain parenchyma shortly after oral administration, and modulate the expression of Egr-1, c-Jun and c-Fos. Molecular docking assay disclosed that harmine molecule could directly dock into the catalytic active site of acetylcholinesterase, which was partially confirmed by its in vivo inhibitory activity on acetylcholinesterase. Taken together, all these results suggested that harmine could ameliorate impaired memory by enhancement of cholinergic neurotransmission via inhibiting the activity of acetylcholinesterase, which may contribute to its clinical use in the therapy of neurological diseases characterized with acetylcholinesterase deficiency.

  7. Protective effects of mangosteen extract on H2O2-induced cytotoxicity in SK-N-SH cells and scopolamine-induced memory impairment in mice.

    PubMed

    Sattayasai, Jintana; Chaonapan, Pongsatorn; Arkaravichie, Tarinee; Soi-Ampornkul, Rungtip; Junnu, Sarawut; Charoensilp, Patcharakajee; Samer, Jutima; Jantaravinid, Jiraporn; Masaratana, Patarabutr; Suktitipat, Bhoom; Manissorn, Juthatip; Thongboonkerd, Visith; Neungton, Neelobol; Moongkarndi, Primchanien

    2013-01-01

    Mangosteen extracts (ME) contain high levels of polyphenolic compounds and antioxidant activity. Protective effects of ME against β-amyloid peptide (Aβ), induced cytotoxicity have been reported. Here, we further studied the protective effects of ME against oxidative stress induced by hydrogen peroxide (H2O2) and polychlorinated biphenyls (PCBs), and demonstrated the protection against memory impairment in mice. The cytoprotective effects of ME were measured as cell viability and the reduction in ROS activity. In SK-N-SH cell cultures, 200 μg/ml ME could partially antagonize the effects of 150 or 300 µM H2O2 on cell viability, ROS level and caspase-3 activity. At 200, 400 or 800 µg/ml, ME reduced AChE activity of SK-N-SH cells to about 60% of the control. In vivo study, Morris water maze and passive avoidance tests were used to assess the memory of the animals. ME, especially at 100 mg/kg body weight, could improve the animal's memory and also antagonize the effect of scopolamine on memory. The increase in ROS level and caspase-3 activity in the brain of scopolamine-treated mice were antagonized by the ME treatment. The study demonstrated cytoprotective effects of ME against H2O2 and PCB-52 toxicity and having AChE inhibitory effect in cell culture. ME treatment in mice could attenuate scopolamine-induced memory deficit and oxidative stress in brain.

  8. Protective Effects of Mangosteen Extract on H2O2-Induced Cytotoxicity in SK-N-SH Cells and Scopolamine-Induced Memory Impairment in Mice

    PubMed Central

    Sattayasai, Jintana; Chaonapan, Pongsatorn; Arkaravichie, Tarinee; Soi-ampornkul, Rungtip; Junnu, Sarawut; Charoensilp, Patcharakajee; Samer, Jutima; Jantaravinid, Jiraporn; Masaratana, Patarabutr; Suktitipat, Bhoom; Manissorn, Juthatip; Thongboonkerd, Visith; Neungton, Neelobol; Moongkarndi, Primchanien

    2013-01-01

    Mangosteen extracts (ME) contain high levels of polyphenolic compounds and antioxidant activity. Protective effects of ME against β-amyloid peptide (Aβ), induced cytotoxicity have been reported. Here, we further studied the protective effects of ME against oxidative stress induced by hydrogen peroxide (H2O2) and polychlorinated biphenyls (PCBs), and demonstrated the protection against memory impairment in mice. The cytoprotective effects of ME were measured as cell viability and the reduction in ROS activity. In SK-N-SH cell cultures, 200 μg/ml ME could partially antagonize the effects of 150 or 300 µM H2O2 on cell viability, ROS level and caspase-3 activity. At 200, 400 or 800 µg/ml, ME reduced AChE activity of SK-N-SH cells to about 60% of the control. In vivo study, Morris water maze and passive avoidance tests were used to assess the memory of the animals. ME, especially at 100 mg/kg body weight, could improve the animal’s memory and also antagonize the effect of scopolamine on memory. The increase in ROS level and caspase-3 activity in the brain of scopolamine-treated mice were antagonized by the ME treatment. The study demonstrated cytoprotective effects of ME against H2O2 and PCB-52 toxicity and having AChE inhibitory effect in cell culture. ME treatment in mice could attenuate scopolamine-induced memory deficit and oxidative stress in brain. PMID:24386444

  9. Attenuation of scopolamine-induced cognitive dysfunction by obovatol.

    PubMed

    Choi, Dong-Young; Lee, Young-Jung; Lee, Sun Young; Lee, Yoot Mo; Lee, Hyun Hee; Choi, Im Seop; Oh, Ki-Wan; Han, Sang Bae; Nam, Sang-Yoon; Hong, Jin Tae

    2012-07-01

    Alzheimer's disease (AD) is the most prevalent cause of dementia in the elderly people. The disease is pathologically characterized by extracellular deposition of beta-amyloid peptide (Aβ), cholinergic neurodegeneration and elevation of acetylcholine esterase (AChE) activity in the affected regions. In this study, we investigated the effects of obovatol on memory dysfunction, which was caused by scopolamine. Obovatol (0.2, 0.5 and 1 mg/kg for 7 day) attenuated scopolamine (1 mg/kg, i.p.)-induced amnesia in a dose-dependent manner, as revealed by the Morris water maze test and step-through passive avoidance test. Mechanism studies exhibited that obovatol dose-dependently alleviated scopolamine-induced increase in Aβ generation and β-secretase activity in the cortex and hippocampus. Obovatol also attenuated scopolamine-induced rise in AChE activity in the cortex and hippocampus. Obovatol might rescue scopolamine-mediated impaired learning and memory function by attenuating Aβ accumulation and stabilizing cholinergic neurotransmission, which suggests that the natural compound could be a useful agent for the prevention of the development or progression of AD neurodegeneration.

  10. Anti-Amnesic Effect of Fermented Ganoderma lucidum Water Extracts by Lactic Acid Bacteria on Scopolamine-Induced Memory Impairment in Rats

    PubMed Central

    Choi, Yu Jin; Yang, Hee Sun; Jo, Jun Hee; Lee, Sang Cheon; Park, Tae Young; Choi, Bong Suk; Seo, Kyoung Sun; Huh, Chang Ki

    2015-01-01

    This study investigated the anti-amnesic effect of fermented Ganoderma lucidum water extracts (GW) on scopolamine-induced memory impairment in rats. GW were fermented by the lactic acid bacterium Bifidobacterium bifidum (FGWB), followed by Lactobacillus sakei LI033 (FGWBL). To induce amnesia, scopolamine (1 mg/kg) was intraperitoneally injected into rats 30 min before the behavioral tests. Step-through latencies of rats treated with primary fermented extracts (300 mg/kg, FGWB) and secondary fermented extracts (300 mg/kg, FGWBL) were significantly longer than those of rats treated with GW (300 mg/kg) in the retention trial of the multiple trial passive avoidance test. In the Morris water maze task, FGWBL significantly shortened escape latencies in training trials. Furthermore, swimming times within the target zone during the probe trial with FGWBL were significantly higher than the GW and FGWB treatments. In addition, acetylcholinesterase activities were lower in the brains of scopolamine-treated rats treated with FGWBL. These results suggest that FGWBL could be useful to enhance learning memory and cognitive function via cholinergic dysfunction. PMID:26176000

  11. Comparison of ginsenosides Rg1 and Rb1 for their effects on improving scopolamine-induced learning and memory impairment in mice.

    PubMed

    Wang, Qiong; Sun, Li-Hua; Jia, William; Liu, Xin-Min; Dang, Hai-Xia; Mai, Wen-Li; Wang, Ning; Steinmetz, Andre; Wang, Yu-Qin; Xu, Chang-Jiang

    2010-12-01

    Rg1 and Rb1 are two major active compounds of ginseng that facilitate learning and memory. The present study aimed to compare the nootropic effects of Rg1 and Rb1 in a scopolamine induced dementia mice model. After 6 and 12 mg/kg of Rg1 and Rb1 intraperitoneal administration to mice for 7 days, their effects were assessed using the step-down passive avoidance (SD) and the Morris water maze (MWM) tests, the acetylcholinesterase (AChE) activity, acetylcholine (ACh) content and serotonin (5-HT) level in the hippocampus were analysed after SD and MWM tests. The results showed that Rg1 and Rb1 ameliorated cognition-deficiency in mice with dementia. Rg1 showed stronger effects than Rb1 on escape acquisition in MWM. Both Rg1 and Rb1 increased ACh levels in the hippocampus, but Rg1 inhibited AChE activity while Rb1 had no effect on AChE activity. Both Rg1 and Rb1 inhibited the decrease of 5-HT induced by scopolamine, but Rb1 was more active than the same dose of Rg1. These results demonstrate that multiple administrations of Rg1 and Rb1 are effective in improving memory deficiency induced by scopolamine. Rg1 appears to be more potent than Rb1 in improving acquisition impairment, and the two ginsenosides may act through different mechanisms.

  12. The ameliorating effects of 2,3-dihydroxy-4-methoxyacetophenone on scopolamine-induced memory impairment in mice and its neuroprotective activity.

    PubMed

    Weon, Jin Bae; Ko, Hyun-Jeong; Ma, Choong Je

    2013-12-15

    We isolated 2,3-dihydroxy-4-methoxyacetophenone, a neuroprotective compound from Cynenchum paniculatum in our previous study. The present study was conducted to investigate the possible neuroprotective effect of 2,3-dihydroxy-4-methoxyacetophenone that has been previously isolated from Cynenchum paniculatum on hippocampal neuronal cell line, HT22 cells and its possible cognitive-enhancing effect on scopolamine-induced amnesia in mice. Neuroprotective effect against glutamate-induced neurotoxicity in HT22 cells was evaluated by MTT assay. Also, cognitive enhancing effect against scopolamine (1mg/kg, ip) induced learning and memory deficit was measured by Morris water maze test. Oral administered of 2,3-dihydroxy-4-methoxyacetophenone (1, 10, 20, 40 and 50mg/kg) to amnesic mice induced by scopolamine. In Morris water maze test, 2,3-dihydroxy-4-methoxyacetophenone (50mg/kg) improved the impairment of spatial memory induced by scopolamine. 2,3-Dihydroxy-4-methoxyacetophenone protect HT22 cells on glutamate induced cell-death in a dose-dependent manner (EC50 value: 10.94μM). Furthermore, 2,3-dihydroxy-4-methoxyacetophenone was found to inhibit [Ca(2+)] accumulation in HT22 cells and had antioxidantive activity. The results showed that 2,3-dihydroxy-4-methoxyacetophenone exert neuroprotective and cognitive-enhancing activities through its antioxidant activity. We suggest that 2,3-dihydroxy-4-methoxyacetophenone improves cognitive function and may be helpful for the treatment of Alzheimer's disease.

  13. Tetramethylpyrazine protects against scopolamine-induced memory impairments in rats by reversing the cAMP/PKA/CREB pathway.

    PubMed

    Wu, Wei; Yu, Xiao; Luo, Xiao-Ping; Yang, Shu-Hua; Zheng, Dong

    2013-09-15

    Tetramethylpyrazine is used in the treatment of many neurological diseases because of its neuroprotective effect. Here, we demonstrate that administration of tetramethylpyrazine effectively reverses memory deficits induced by scopolamine. Moreover, tetramethylpyrazine preserves postsynaptic protein synthesis and restores cAMP/PKA/CREB pathway signaling deficits. Our study not only explores the actions of tetramethylpyrazine on synapses, but also provides novel evidence for the possible therapeutic use of tetramethylpyrazine in dementia.

  14. Effects of rivastigmine and memantine alone and in combination on learning and memory in rats with scopolamine-induced amnesia

    PubMed Central

    Yanev, Peter Georgiev; Dimitrova, Darinka Slavcheva

    2015-01-01

    Background Cholinesterase inhibitors and glutamate blockers are commonly used for the treatment of cognitive impairment in Alzheimer’s disease. The aim was to evaluate the effects of rivastigmine and memantine alone or in combination in rats with scopolamine-impaired memory. Method 5 groups of rats were used: control, scopolamine (model), model with rivastigmine, model with memantine, and model with both drugs. Active avoidance test was performed and the number of conditioned responses, unconditioned responses and intertrial crossing were recorded. Passive avoidance tests step-through with criteria latency of reaction 180 s in the light chamber and step-down with criteria latency of reaction 60 s on the platform were done. Results Control rats learned the task and kept it on memory tests. Scopolamine treated rats failed to perform it. The rivastigmine, memantine and its combination groups showed increased CRs during learning and memory retention tests. In both passive avoidance tests an increased latency of reaction was observed in the drug treated groups. Conclusion The combination of both drugs rivastigmine and memantine is more effective than the use of the single drug in cognitive impaired rats. Cholinesterase inhibitors and NMDA blockers may be combined in the treatment of different kind of dementias.

  15. Hippocampal memory enhancing activity of pine needle extract against scopolamine-induced amnesia in a mouse model

    PubMed Central

    Lee, Jin-Seok; Kim, Hyeong-Geug; Lee, Hye-Won; Han, Jong-Min; Lee, Sam-Keun; Kim, Dong-Woon; Saravanakumar, Arthanari; Son, Chang-Gue

    2015-01-01

    We evaluated the neuropharmacological effects of 30% ethanolic pine needle extract (PNE) on memory impairment caused by scopolamine injection in mice hippocampus. Mice were orally pretreated with PNE (25, 50, and 100 mg/kg) or tacrine (10 mg/kg) for 7 days, and scopolamine (2 mg/kg) was injected intraperitoneally, 30 min before the Morris water maze task on first day. To evaluate memory function, the Morris water maze task was performed for 5 days consecutively. Scopolamine increased the escape latency and cumulative path-length but decreases the time spent in target quadrant, which were ameliorated by pretreatment with PNE. Oxidant-antioxidant balance, acetylcholinesterase activity, neurogenesis and their connecting pathway were abnormally altered by scopolamine in hippocampus and/or sera, while those alterations were recovered by pretreatment with PNE. As lipid peroxidation, 4HNE-positive stained cells were ameliorated in hippocampus pretreated with PNE. Pretreatment with PNE increased the proliferating cells and immature neurons against hippocampal neurogenesis suppressed by scopolamine, which was confirmed by ki67- and DCX-positive stained cells. The expression of brain-derived neurotrophic factor (BDNF) and phosphorylated cAMP response element-binding protein (pCREB) in both protein and gene were facilitated by PNE pretreatment. These findings suggest that PNE could be a potent neuropharmacological drug against amnesia, and its possible mechanism might be modulating cholinergic activity via CREB-BDNF pathway. PMID:25974329

  16. Hippocampal memory enhancing activity of pine needle extract against scopolamine-induced amnesia in a mouse model.

    PubMed

    Lee, Jin-Seok; Kim, Hyeong-Geug; Lee, Hye-Won; Han, Jong-Min; Lee, Sam-Keun; Kim, Dong-Woon; Saravanakumar, Arthanari; Son, Chang-Gue

    2015-05-14

    We evaluated the neuropharmacological effects of 30% ethanolic pine needle extract (PNE) on memory impairment caused by scopolamine injection in mice hippocampus. Mice were orally pretreated with PNE (25, 50, and 100 mg/kg) or tacrine (10 mg/kg) for 7 days, and scopolamine (2 mg/kg) was injected intraperitoneally, 30 min before the Morris water maze task on first day. To evaluate memory function, the Morris water maze task was performed for 5 days consecutively. Scopolamine increased the escape latency and cumulative path-length but decreases the time spent in target quadrant, which were ameliorated by pretreatment with PNE. Oxidant-antioxidant balance, acetylcholinesterase activity, neurogenesis and their connecting pathway were abnormally altered by scopolamine in hippocampus and/or sera, while those alterations were recovered by pretreatment with PNE. As lipid peroxidation, 4HNE-positive stained cells were ameliorated in hippocampus pretreated with PNE. Pretreatment with PNE increased the proliferating cells and immature neurons against hippocampal neurogenesis suppressed by scopolamine, which was confirmed by ki67- and DCX-positive stained cells. The expression of brain-derived neurotrophic factor (BDNF) and phosphorylated cAMP response element-binding protein (pCREB) in both protein and gene were facilitated by PNE pretreatment. These findings suggest that PNE could be a potent neuropharmacological drug against amnesia, and its possible mechanism might be modulating cholinergic activity via CREB-BDNF pathway.

  17. The effects of daidzin and its aglycon, daidzein, on the scopolamine-induced memory impairment in male mice.

    PubMed

    Kim, Dong Hyun; Jung, Hyun Ah; Park, Se Jin; Kim, Jong Min; Lee, Seungjoo; Choi, Jae Su; Cheong, Jae Hoon; Ko, Kwang Ho; Ryu, Jong Hoon

    2010-10-01

    In this study, the effect of daidzin or daidzein isolated from Pueraria lobata on the memory impairments induced by scopolamine was assessed in male mice using the passive avoidance and the Morris water maze tasks. Administration of daidzin (5 mg/kg) or daidzein (5 mg/kg) significantly reversed the scopolamine (1 mg/kg)-induced cognitive impairments in male mice as evidenced by the passive avoidance test (p < 0.05) and on the Morris water maze test (p < 0.05). Moreover, the ameliorating effects of daidzin or daidzein were antagonized by tamoxifen (1 mg/kg), the nonspecific estrogen receptor antagonist. These results indicate that daidzin or daidzein may be useful in cognitive impairment induced by cholinergic dysfunction, and this beneficial effect is mediated, in part, via estrogen receptor.

  18. Protection against brain tissues oxidative damage as a possible mechanism for improving effects of low doses of estradiol on scopolamine-induced learning and memory impairments in ovariectomized rats

    PubMed Central

    Hejazian, Seyed Hassan; Karimi, Sareh; Hosseini, Mahmoud; Mousavi, Seyed Mojtaba; Soukhtanloo, Mohammad

    2016-01-01

    Background: Regarding the anti-oxidative effects on the central nervous system, the possible protection against brain tissues oxidative damage as a possible mechanism for improving effects of low doses of estradiol on scopolamine-induced learning and memory impairments was investigated in ovariectomized (OVX) rats. Materials and Methods: The OVX rats treated by (1) vehicle, (2) scopolamine, and (3–4) scopolamine plus estradiol (20 or 20 or 60 μg/kg). Estradiol was administered (20 or 60 μg/kg, intraperitoneally) daily for 6 weeks after ovariectomy. The rats were examined for learning and memory using passive avoidance test. Scopolamine (2 mg/kg) was injected 30 min after training in the test. The brains were then removed to determine malondialdehyde (MDA) and thiol contents. Results: Scopolamine shortened the time latency to enter the dark compartment in (P < 0.01). Compared to scopolamine, pretreatment by both doses of estradiol prolonged the latency to enter the dark compartment (P < 0.01). The brain tissues MDA concentration as an index of lipid peroxidation was decreased (P < 0.05). Pretreatment by estradiol lowered the concentration of MDA, while it increased thiol content compared to scopolamine (P < 0.05 and P < 0.01). Conclusions: These results allow us to suggest a protection against brain tissues oxidative damage as a possible mechanism for improving effects of low doses of estradiol on scopolamine-induced learning and memory impairments in OVX rats. PMID:27563633

  19. Fermented Sipjeondaebo-tang Alleviates Memory Deficits and Loss of Hippocampal Neurogenesis in Scopolamine-induced Amnesia in Mice

    PubMed Central

    Park, Hee Ra; Lee, Heeeun; Park, Hwayong; Cho, Won-Kyung; Ma, Jin Yeul

    2016-01-01

    We investigated the anti-amnesic effects of SJ and fermented SJ (FSJ) on scopolamine (SCO)-induced amnesia mouse model. Mice were orally co-treated with SJ or FSJ (125, 250, and 500 mg/kg) and SCO (1 mg/kg), which was injected intraperitoneally for 14 days. SCO decreased the step-through latency and prolonged latency time to find the hidden platform in the passive avoidance test and Morris water maze test, respectively, and both SCO effects were ameliorated by FSJ treatment. FSJ was discovered to promote hippocampal neurogenesis during SCO treatment by increasing proliferation and survival of BrdU-positive cells, immature/mature neurons. In the hippocampus of SCO, oxidative stress and the activity of acetylcholinesterase were elevated, whereas the levels of acetylcholine and choline acetyltransferase were diminished; however, all of these alterations were attenuated by FSJ-treatment. The alterations in brain-derived neurotrophic factor, phosphorylated cAMP response element-binding protein, and phosphorylated Akt that occurred following SCO treatment were protected by FSJ administration. Therefore, our findings are the first to suggest that FSJ may be a promising therapeutic drug for the treatment of amnesia and aging-related or neurodegenerative disease-related memory impairment. Furthermore, the molecular mechanism by which FSJ exerts its effects may involve modulation of the cholinergic system and BDNF/CREB/Akt pathway. PMID:26939918

  20. Fermented Sipjeondaebo-tang Alleviates Memory Deficits and Loss of Hippocampal Neurogenesis in Scopolamine-induced Amnesia in Mice.

    PubMed

    Park, Hee Ra; Lee, Heeeun; Park, Hwayong; Cho, Won-Kyung; Ma, Jin Yeul

    2016-03-04

    We investigated the anti-amnesic effects of SJ and fermented SJ (FSJ) on scopolamine (SCO)-induced amnesia mouse model. Mice were orally co-treated with SJ or FSJ (125, 250, and 500 mg/kg) and SCO (1 mg/kg), which was injected intraperitoneally for 14 days. SCO decreased the step-through latency and prolonged latency time to find the hidden platform in the passive avoidance test and Morris water maze test, respectively, and both SCO effects were ameliorated by FSJ treatment. FSJ was discovered to promote hippocampal neurogenesis during SCO treatment by increasing proliferation and survival of BrdU-positive cells, immature/mature neurons. In the hippocampus of SCO, oxidative stress and the activity of acetylcholinesterase were elevated, whereas the levels of acetylcholine and choline acetyltransferase were diminished; however, all of these alterations were attenuated by FSJ-treatment. The alterations in brain-derived neurotrophic factor, phosphorylated cAMP response element-binding protein, and phosphorylated Akt that occurred following SCO treatment were protected by FSJ administration. Therefore, our findings are the first to suggest that FSJ may be a promising therapeutic drug for the treatment of amnesia and aging-related or neurodegenerative disease-related memory impairment. Furthermore, the molecular mechanism by which FSJ exerts its effects may involve modulation of the cholinergic system and BDNF/CREB/Akt pathway.

  1. A Special Extract of Bacopa monnieri (CDRI-08) Restores Learning and Memory by Upregulating Expression of the NMDA Receptor Subunit GluN2B in the Brain of Scopolamine-Induced Amnesic Mice

    PubMed Central

    Rai, Rakesh; Singh, Hemant K.; Prasad, S.

    2015-01-01

    In the present communication, we have investigated effects of the CDRI-08, a well characterized extract of Bacopa monnieri, on expression of the GluN2B subunit of NMDAR in various brain regions of the scopolamine-induced amnesic mice. Our behavioral data reveal that scopolamine-treated amnesic mice exhibit significant decline in the spatial memory compared to the normal control mice. Our RT-PCR and immunoblotting data revealed that the scopolamine treatment resulted in a significant downregulation of the NMDAR GluN2B subunit expression in prefrontal cortex and hippocampus. Our enzyme assay data revealed that scopolamine caused a significant increase in the acetylcholinesterase activity in both the brain regions. Further, oral administration of the CDRI-08 to scopolamine-treated amnesic mice restored the spatial memory which was found to be associated with significant upregulation of the GluN2B subunit expression and decline in the acetylcholinesterase activity in prefrontal cortex as well as hippocampus towards their levels in the normal control mice. Our study provides the evidence for the mechanism underlying role of the Bacopa monnieri extract (CDRI-08) in restoring spatial memory in amnesic mice, which may have therapeutic implications. PMID:26413117

  2. Attenuating effect of bioactive coumarins from Convolvulus pluricaulis on scopolamine-induced amnesia in mice.

    PubMed

    Malik, Jai; Karan, Maninder; Vasisht, Karan

    2016-01-01

    Convolvulus pluricaulis Chois. (Convolvulaceae) has been used in Ayurveda as Medhya Rasyana (nervine tonic) to treat various mental disorders. This study was designed to isolate the bioactive compound(s) of this plant and to evaluate their effect against scopolamine-induced amnesia. Column chromatography of the chloroform and ethyl-acetate fractions led to the isolation of three coumarins identified as scopoletin, ayapanin and scopolin. All the three compounds at 2.5, 5, 10 and 15 mg/kg, p.o. were evaluated for memory-enhancing activity against scopolamine-induced amnesia using elevated plus maze and step down paradigms. Effect on acetylcholinesterase activity in mice brain was also evaluated. Scopoletin and scopolin, in both the paradigms, significantly and dose dependently attenuated the scopolamine-induced amnesic effect. Furthermore, these compounds at 10 and 15 mg/kg exhibited activity comparable to that of standard drug, donepezil. The compounds also exhibited significant acetylcholinesterase inhibitory activity.

  3. Total isoflavones from soybean and tempeh reversed scopolamine-induced amnesia, improved cholinergic activities and reduced neuroinflammation in brain.

    PubMed

    Ahmad, Aliya; Ramasamy, Kalavathy; Jaafar, Siti Murnirah; Majeed, Abu Bakar Abdul; Mani, Vasudevan

    2014-03-01

    The present study was undertaken to compare the neuroprotective effects between total isoflavones from soybean and tempeh against scopolamine-induced cognitive dysfunction. Total isoflavones (10, 20 and 40mg/kg) from soybean (SI) and tempeh (TI) were administered orally to different groups of rats (n=6) for 15days. Piracetam (400mg/kg, p.o.) was used as a standard drug while scopolamine (1mg/kg, i.p.) was used to induce amnesia in the animals. Radial arm and elevated plus mazes served as exteroceptive behavioural models to measure memory. Brain cholinergic activities (acetylcholine and acetylcholinesterase) and neuroinflammatory activities (COX-1, COX-2, IL-1β and IL10) were also assessed. Treatment with SI and TI significantly reversed the scopolamine effect and improved memory with TI group at 40mg/kg, p.o. exhibiting the best improvement (p<0.001) in rats. The TI (10, 20 and 40mg/kg, p.o.) significantly increased (p<0.001) acetylcholine and reduced acetylcholinesterase levels. Meanwhile, only a high dose (40mg/kg, p.o.) of SI showed significant improvement (p<0.05) in the cholinergic activities. Neuroinflammation study also showed that TI (40mg/kg, p.o.) was able to reduce inflammation better than SI. The TI ameliorates scopolamine-induced memory in rats through the cholinergic neuronal pathway and by prevention of neuroinflammation.

  4. Galantamine reverses scopolamine-induced behavioral alterations in Dugesia tigrina.

    PubMed

    Ramakrishnan, Latha; Amatya, Christina; DeSaer, Cassie J; Dalhoff, Zachary; Eggerichs, Michael R

    2014-09-01

    In planaria (Dugesia tigrina), scopolamine, a nonselective muscarinic receptor antagonist, induced distinct behaviors of attenuated motility and C-like hyperactivity. Planarian locomotor velocity (pLMV) displayed a dose-dependent negative correlation with scopolamine concentrations from 0.001 to 1.0 mM, and a further increase in scopolamine concentration to 2.25 mM did not further decrease pLMV. Planarian hyperactivity counts was dose-dependently increased following pretreatment with scopolamine concentrations from 0.001 to 0.5 mM and then decreased for scopolamine concentrations ≥ 1 mM. Planarian learning and memory investigated using classical Pavlovian conditioning experiments demonstrated that scopolamine (1 mM) negatively influenced associative learning indicated by a significant decrease in % positive behaviors from 86 % (control) to 14 % (1 mM scopolamine) and similarly altered memory retention, which is indicated by a decrease in % positive behaviors from 69 % (control) to 27 % (1 mM scopolamine). Galantamine demonstrated a complex behavior in planarian motility experiments since co-application of low concentrations of galantamine (0.001 and 0.01 mM) protected planaria against 1 mM scopolamine-induced motility impairments; however, pLMV was significantly decreased when planaria were tested in the presence of 0.1 mM galantamine alone. Effects of co-treatment of scopolamine and galantamine on memory retention in planaria via classical Pavlovian conditioning experiments showed that galantamine (0.01 mM) partially reversed scopolamine (1 mM)-induced memory deficits in planaria as the % positive behaviors increased from 27 to 63 %. The results demonstrate, for the first time in planaria, scopolamine's effects in causing learning and memory impairments and galantamine's ability in reversing scopolamine-induced memory impairments.

  5. Aqueous extracts from asparagus stems prevent memory impairments in scopolamine-treated mice.

    PubMed

    Sui, Zifang; Qi, Ce; Huang, Yunxiang; Ma, Shufeng; Wang, Xinguo; Le, Guowei; Sun, Jin

    2017-03-09

    Aqueous extracts from Asparagus officinalis L. stems (AEAS) are rich in polysaccharides, gamma-amino butyric acid (GABA), and steroidal saponin. This study was designed to investigate the effects of AEAS on learning, memory, and acetylcholinesterase-related activity in a scopolamine-induced model of amnesia. Sixty ICR mice were randomly divided into 6 groups (n = 10) including the control group (CT), scopolamine group (SC), donepezil group (DON), low, medium, and high dose groups of AEAS (LS, MS, HS; 1.6 mL kg(-1), 8 mL kg(-1), 16 mL kg(-1)). The results showed that 8 mL kg(-1) of AEAS used in this study significantly reversed scopolamine-induced cognitive impairments in mice in the novel object recognition test (P < 0.05) and the Y-maze test (P < 0.05), and also improved the latency to escape in the Morris water maze test (P < 0.05). Moreover, it significantly increased acetylcholine and inhibited acetylcholinesterase activity in the hippocampus, which was directly related to the reduction in learning and memory impairments. It also reversed scopolamine-induced reduction in the hippocampal brain-derived neurotrophic factor (BDNF) and the cAMP response element-binding protein (CREB) mRNA expression. AEAS protected against scopolamine-induced memory deficits. In conclusion, AEAS protected learning and memory function in mice by enhancing the activity of the cholinergic nervous system, and increasing BDNF and CREB expression. This suggests that AEAS has the potential to prevent cognitive impairments in age-related diseases, such as Alzheimer's disease.

  6. Acetyl-L-carnitine rescues scopolamine-induced memory deficits by restoring insulin-like growth factor II via decreasing p53 oxidation.

    PubMed

    Wang, Xiang; Wang, Liang-Ping; Tang, Hui; Shan, Wan-Ying; Wang, Xiong; Liu, Dan; Wu, Yuan-Yuan; Tian, Qing; Wang, Jian-Zhi; Zhu, Ling-Qiang

    2014-01-01

    Alzheimer's disease (AD) is characterized by the cholinergic neurons loss and impairments of learning and memory. Scopolamine is common used to imitate AD pathological features and also causes an obvious oxidative stress. In this study, we found that intraperitoneal administration of supplementary acetyl-L-carnitine partially reverses the learning and memory defects induced by scopolamine. We also found that acetyl-L-carnitine reverses the impairment of long-term potentiation, dendritic abnormalities, and the impaired recruitment of synaptic protein. The beneficial effects of acetyl-L-carnitine may occur through amelioration of oxidative stress because it effectively decreases the levels of oxidative products and increases the activity of superoxide dismutase; this leads to a recovery in the suppressed activity of p53 caused oxidative stimuli, which in turn restores levels of insulin-like growth factor II, an important hormone for learning and memory. Our study provides the first evidence of the potential utility of acetyl-L-carnitine in treating the synaptic disorders prevalent in AD and other neurodegenerative diseases. This article is part of the Special Issue entitled 'The Synaptic Basis of Neurodegenerative Disorders'.

  7. Agmatine protects against scopolamine-induced water maze performance impairment and hippocampal ERK and Akt inactivation.

    PubMed

    Moosavi, Maryam; Khales, Golnaz Yadollahi; Abbasi, Leila; Zarifkar, Asadollah; Rastegar, Karim

    2012-04-01

    Cholinergic brain activity plays a significant role in memory. Scopolamine a muscarinic cholinergic antagonist is known to induce impairment in Morris water maze performance, the task which is mainly dependent on the hippocampus. It is suggested that hippocampal ERK and Akt activation play roles in synaptic plasticity and some types of learning and memory. Agmatine, a polyamine derived from l-arginine decarboxylation, is recently shown to exert some neuroprotective effects. This study was aimed to investigate if agmatine could reverse scopolamine-induced memory impairment and possible hippocampal ERK and Akt activity alteration. Adult male Sprague-Dawley rats weighing 200-250 g were randomly assigned into 5 groups. The animals were trained for 3 days in Morris water maze and in day 4 their memory retention was assessed in probe trial which was consisted of a 60 s trial with no platform. Scopolamine (1 mg/kg/ip) or saline were injected 30 min and agmatine (20 or 40 mg/kg/ip) was administered 60 min before each session. The hippocampi were isolated after behavioral studies and western blotting studies on hippocampal lysates were done to determine the levels of activated ERK and Akt. Scopolamine treatment not only impaired water maze learning and memory, but also decreased the amount of phosphorylated (activated) ERK and Akt. Agmatine pre-treatment prevented both the learning impairment and hippocampal ERK and Akt inactivation induced by scopolamine. It seems that agmatine may act as a candidate substance against amnesia.

  8. The Protective Role of Selenium on Scopolamine-Induced Memory Impairment, Oxidative Stress, and Apoptosis in Aged Rats: The Involvement of TRPM2 and TRPV1 Channels.

    PubMed

    Balaban, Hasan; Nazıroğlu, Mustafa; Demirci, Kadir; Övey, İshak Suat

    2016-03-28

    Inhibition of Ca(2+) entry into the hippocampus and dorsal root ganglion (DRG) through inhibition of N-methyl-D-aspartate (NMDA) receptor antagonist drugs is the current standard of care in neuronal diseases such as Alzheimer's disease, dementia, and peripheral pain. Oxidative stress activates Ca(2+)-permeable TRPM2 and TRPV1, and recent studies indicate that selenium (Se) is a potent TRPM2 and TRPV1 channel antagonist in the hippocampus and DRG. In this study, we investigated the neuroprotective properties of Se in primary hippocampal and DRG neuron cultures of aged rats when given alone or in combination with scopolamine (SCOP). Thirty-two aged (18-24 months old) rats were divided into four groups. The first and second groups received a placebo and SCOP (1 mg/kg/day), respectively. The third and fourth groups received intraperitoneal Se (1.5 mg/kg/ over day) and SCOP + Se, respectively. The hippocampal and DRG neurons also were stimulated in vitro with a TRPV1 channel agonist (capsaicin) and a TRPM2 channel agonist (cumene hydroperoxide). We found that Se was fully effective in reversing SCOP-induced TRPM2 and TRPV1 current densities as well as errors in working memory and reference memory. In addition, Se completely reduced SCOP-induced oxidative toxicity by modulating lipid peroxidation, reducing glutathione and glutathione peroxidase. The Se and SCOP + Se treatments also decreased poly (ADP-ribose) polymerase activity, intracellular free Ca(2+) concentrations, apoptosis, and caspase 3, caspase 9, and mitochondrial membrane depolarization values in the hippocampus. In conclusion, the current study reports on the cellular level for SCOP and Se on the different endocytotoxic cascades for the first time. Notably, the research indicates that Se can result in remarkable neuroprotective and memory impairment effects in the hippocampal neurons of rats. Graphical abstract Possible molecular pathways of involvement of selenium (Se) in scopolamine (SCOP) induced

  9. Ameliorative effect of betulin from Betula platyphylla bark on scopolamine-induced amnesic mice.

    PubMed

    Cho, Namki; Kim, Hyeon Woo; Lee, Hee Kyoung; Jeon, Byung Ju; Sung, Sang Hyun

    2015-01-01

    Alzheimer's disease (AD) is a neurodegenerative disease induced by cholinergic neuron damage or amyloid-beta aggregation in the basal forebrain region and resulting in cognitive disorder. We previously reported on the neuroprotective effects of Betula platyphylla bark (BPB) in an amyloid-beta-induced amnesic mouse model. In this study, we obtained a cognitive-enhancing compound by assessing results using a scopolamine-induced amnesic mouse model. Our results show that oral treatment of mice with BPB and betulin significantly ameliorated scopolamine-induced memory deficits in both passive avoidance and Y-maze tests. In the Morris water maze test, administration of BPB and betulin significantly improved memory and cognitive function indicating the formation of working and reference memories in treated mice. Moreover, betulin significantly increased glutathione content in mouse hippocampus, and the increase was greater than that from betulinic acid treatment. We conclude that BPB and its active component betulin have potential as therapeutic, cognitive enhancer in AD.

  10. Protective Role of Ashwagandha Leaf Extract and Its Component Withanone on Scopolamine-Induced Changes in the Brain and Brain-Derived Cells

    PubMed Central

    Singh, Rumani; Saxena, Nishant; Kaul, Sunil C.; Wadhwa, Renu; Thakur, Mahendra K.

    2011-01-01

    Background Scopolamine is a well-known cholinergic antagonist that causes amnesia in human and animal models. Scopolamine-induced amnesia in rodent models has been widely used to understand the molecular, biochemical, behavioral changes, and to delineate therapeutic targets of memory impairment. Although this has been linked to the decrease in central cholinergic neuronal activity following the blockade of muscarinic receptors, the underlying molecular and cellular mechanism(s) particularly the effect on neuroplasticity remains elusive. In the present study, we have investigated (i) the effects of scopolamine on the molecules involved in neuronal and glial plasticity both in vivo and in vitro and (ii) their recovery by alcoholic extract of Ashwagandha leaves (i-Extract). Methodology/Principal Findings As a drug model, scopolamine hydrobromide was administered intraperitoneally to mice and its effect on the brain function was determined by molecular analyses. The results showed that the scopolamine caused downregulation of the expression of BDNF and GFAP in dose and time dependent manner, and these effects were markedly attenuated in response to i-Extract treatment. Similar to our observations in animal model system, we found that the scopolamine induced cytotoxicity in IMR32 neuronal and C6 glioma cells. It was associated with downregulation of neuronal cell markers NF-H, MAP2, PSD-95, GAP-43 and glial cell marker GFAP and with upregulation of DNA damage- γH2AX and oxidative stress- ROS markers. Furthermore, these molecules showed recovery when cells were treated with i-Extract or its purified component, withanone. Conclusion Our study suggested that besides cholinergic blockade, scopolamine-induced memory loss may be associated with oxidative stress and Ashwagandha i-Extract, and withanone may serve as potential preventive and therapeutic agents for neurodegenerative disorders and hence warrant further molecular analyses. PMID:22096544

  11. Blockade of the dorsal hippocampal dopamine D1 receptors inhibits the scopolamine-induced state-dependent learning in rats.

    PubMed

    Piri, M; Rostampour, M; Nasehi, M; Zarrindast, M R

    2013-11-12

    In the present study, we investigated the possible role of the dorsal hippocampal (CA1) dopamine D1 receptors on scopolamine-induced amnesia as well as scopolamine state-dependent memory in adult male Wistar rats. Animals were bilaterally implanted with chronic cannulae in the CA1 regions of the dorsal hippocampus, trained in a step-through type inhibitory avoidance task, and tested 24h after training for their step-through latency. Results indicated that pre-training or pre-test intra-CA1 administration of scopolamine (1.5 and 3 μg/rat) dose-dependently reduced the step-through latency, showing an amnestic response. The pre-training scopolamine-induced amnesia (3 μg/rat) was reversed by the pre-test administration of scopolamine, indicating a state-dependent effect. Similarly, the pre-test administration of dopamine D1 receptor agonist, 1-phenyl-7,8-dihydroxy-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochloride (SKF38393; 1, 2 and 4 μg/rat, intra-CA1), could significantly reverse the scopolamine-induced amnesia. Interestingly, administration of an ineffective dose of scopolamine (0.25 μg/rat, intra-CA1) before different doses of SKF38393, blocked the reversal effect of SKF38393 on the pre-training scopolamine-induced amnesia. Moreover, while the pre-test intra-CA1 injection of the dopamine D1 receptor antagonist, R(+)-7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine hydrochloride (SCH23390; 0.1 and 0.5 μg/rat, intra-CA1), resulted in apparent memory impairment, microinjection of the same doses of this agent inhibited the scopolamine-induced state-dependent memory. These results indicate that the CA1 dopamine D1 receptors may potentially play an important role in scopolamine-induced amnesia as well as the scopolamine state-dependent memory. Furthermore, our results propose that dopamine D1 receptor agonist, SKF38393 reverses the scopolamine-induced amnesia via acetylcholine release and possibly through the activation of muscarinic

  12. Estrogen levels modify scopolamine-induced amnesia in gonadally intact rats.

    PubMed

    de Macêdo Medeiros, André; Izídio, Geison Souza; Sousa, Diego Silveira; Macedo, Priscila Tavares; Silva, Anatildes Feitosa; Shiramizu, Victor Kenji Medeiros; Cabral, Alicia; Ribeiro, Alessandra Mussi; Silva, Regina Helena

    2014-08-04

    Previous studies suggested that estrogen plays a role in cognitive function by modulating the cholinergic transmission. However, most of the studies dealing with this subject have been conducted using ovariectomized rats. In the present study we evaluated the effects of physiological and supra-physiological variation of estrogen levels on scopolamine-induced amnesia in gonadally intact female rats. We used the plus-maze discriminative avoidance task (PMDAT) in order to evaluate anxiety levels and motor activity concomitantly to the memory performance. In experiment 1, female Wistar rats in each estrous cycle phase received scopolamine (1 mg/kg) or saline i.p. 20 min before the training session in the PMDAT. In experiment 2, rats in diestrus received estradiol valerate (1 mg/kg) or sesame oil i.m., and scopolamine (1 mg/kg) or saline i.p., 45 min and 20 min before the training, respectively. In experiment 3, rats in diestrus received scopolamine (1 mg/kg) or saline i.p. 20 min before the training, and estradiol valerate (1 mg/kg) or sesame oil i.m. immediately after the training session. In all experiments, a test session was performed 24 h later. The main results showed that: (1) scopolamine impaired retrieval and induced anxiolytic and hyperlocomotor effects in all experiments; (2) this cholinergic antagonist impaired acquisition only in animals in diestrus; (3) acute administration of estradiol valerate prevented the learning impairment induced by scopolamine and (4) interfered with memory consolidation process. The results suggest that endogenous variations in estrogen levels across the estrous cycle modulate some aspects of memory mediated by the cholinergic system. Indeed, specifically in diestrus, a stage with low estrogen levels, the impairment produced by scopolamine on the acquisition was counteracted by exogenous administration of the hormone, whereas the posttraining treatment potentiated the negative effects of scopolamine during the consolidation phase

  13. Scopolamine induced amnesia is reversed by Bacopa monniera through participation of kinase-CREB pathway.

    PubMed

    Saraf, Manish Kumar; Anand, Akshay; Prabhakar, Sudesh

    2010-02-01

    Scopolamine, an anticholinergic drug, is reported to produce amnesia by interference of long term potentiation and has been used for discerning the efficacy of various antiamnesic drugs. The intoxication with anticholinergics and benzodiazepines tend to produce neurodegeneration which cause memory deficits. Our earlier reports have shown the antiamnesic drug, B. monniera to be capable of alleviating diazepam induced memory deficits. We have now tested how scopolamine affects downstream signaling molecules of long term potentiation and if B. monniera can also modulate the scopolamine induced amnesia. We used Morris water maze scale to test the amnesic effect of scopolamine and its reversal by B. monniera. Rota-rod test was used to screen muscle coordination activity of mice before water maze investigations were carried out. The results showed that scopolamine downregulated protein kinase C and iNOS without affecting cAMP, protein kinase A, calmodulin, MAP kinase, nitrite, CREB and pCREB. B. monniera reversed the scopolamine induced amnesia by significantly improving calmodulin and by partially attenuating protein kinase C and pCREB. These observations suggest involvement of calmodulin in evoking antiamnesic effects of B. monniera.

  14. Lactucopicrin ameliorates oxidative stress mediated by scopolamine-induced neurotoxicity through activation of the NRF2 pathway.

    PubMed

    Venkatesan, Ramu; Subedi, Lalita; Yeo, Eui-Ju; Kim, Sun Yeou

    2016-10-01

    Cholinergic activity plays a vital role in cognitive function, and is reduced in individuals with neurodegenerative diseases. Scopolamine, a muscarinic cholinergic antagonist, has been employed in many studies to understand, identify, and characterize therapeutic targets for Alzheimer's disease (AD). Scopolamine-induced dementia is associated with impairments in memory and cognitive function, as seen in patients with AD. The current study aimed to investigate the molecular mechanisms underlying scopolamine-induced cholinergic neuronal dysfunction and the neuroprotective effect of lactucopicrin, an inhibitor of acetylcholine esterase (AChE). We investigated apoptotic cell death, caspase activation, generation of reactive oxygen species (ROS), mitochondrial dysfunction, and the expression levels of anti- and pro-apoptotic proteins in scopolamine-treated C6 cells. We also analyzed the expression levels of antioxidant enzymes and nuclear factor (erythroid-derived 2)-like 2 (NRF2) in C6 cells and neurite outgrowth in N2a neuroblastoma cells. Our results revealed that 1 h scopolamine pre-treatment induced cytotoxicity by increasing apoptotic cell death via oxidative stress-mediated caspase 3 activation and mitochondrial dysfunction. Scopolamine also downregulated the expression the antioxidant enzymes superoxide dismutase, glutathione peroxidase, and catalase, and the transcription factor NRF2. Lactucopicrin treatment protected C6 cells from scopolamine-induced toxicity by reversing the effects of scopolamine on those markers of toxicity. In addition, scopolamine attenuated the secretion of neurotrophic nerve growth factor (NGF) in C6 cells and neurite outgrowth in N2a cells. As expected, lactucopicrin treatment enhanced NGF secretion and neurite outgrowth. Our study is the first to show that lactucopicrin, a potential neuroprotective agent, ameliorates scopolamine-induced cholinergic dysfunction via NRF2 activation and subsequent expression of antioxidant enzymes.

  15. Nootropic activity of Crataeva nurvala Buch-Ham against scopolamine induced cognitive impairment

    PubMed Central

    Bhattacharjee, Atanu; Shashidhara, Shastry Chakrakodi; Saha, Santanu

    2015-01-01

    Loss of cognition is one of the age related mental problems and a characteristic symptom of neurodegenerative disorders like Alzheimer’s. Crataeva nurvala Buch-Ham, a well explored traditional Indian medicinal plant of Westernghats, is routinely used as folkloric medicine to treat various ailments in particular urolithiasis and neurological disorders associated with cognitive dysfunction. The objective of the study was to evaluate the nootropic activity of Crataeva nurvala Buch-Ham stem bark in different learning and memory paradigm viz. Elevated plus maze and Y-maze against scopolamine induced cognitive impairment. Moreover, to elucidate possible mechanism, we studied the influence of Crataeva nurvala ethanolic extract on central cholinergic activity via estimating the whole brain acetyl cholinesterase enzyme. Ethanolic extracts of Crataeva nurvala (100, 200 and 400 mg/kg body weight) were administered to adult Wistar rats for successive seven days and the acquisition, retention and retrieval of spatial recognition memory was determined against scopolamine (1 mg/kg, i.p.) induced amnesia through exteroceptive behavioral models viz. Elevated plus maze and Y-maze models. Further, whole brain acetyl cholinesterase enzyme was estimated through Ellman’s method. Pretreatment with Crataeva nurvala ethanolic extract significantly improved spatial learning and memory against scopolamine induced amnesia. Moreover, Crataeva nurvala extract decreased rat brain acetyl cholinesterase activity in a dose dependent manner and comparable to the standard drug Piracetam. The results indicate that ethanolic extract of Crataeva nurvala might be a useful as nootropic agent to delay the onset and reduce the severity of symptoms associated with dementia and Alzheimer’s disease. The underlying mechanism of action of its nootropic potentiality might be attributed to its anticholinesterase property. PMID:27065767

  16. Task- and Treatment Length-Dependent Effects of Vortioxetine on Scopolamine-Induced Cognitive Dysfunction and Hippocampal Extracellular Acetylcholine in Rats.

    PubMed

    Pehrson, Alan L; Hillhouse, Todd M; Haddjeri, Nasser; Rovera, Renaud; Porter, Joseph H; Mørk, Arne; Smagin, Gennady; Song, Dekun; Budac, David; Cajina, Manuel; Sanchez, Connie

    2016-09-01

    Major depressive disorder (MDD) is a common psychiatric disorder that often features impairments in cognitive function, and these cognitive symptoms can be important determinants of functional ability. Vortioxetine is a multimodal antidepressant that may improve some aspects of cognitive function in patients with MDD, including attention, processing speed, executive function, and memory. However, the cause of these effects is unclear, and there are several competing theories on the underlying mechanism, notably including regionally-selective downstream enhancement of glutamate neurotransmission and increased acetylcholine (ACh) neurotransmission. The current work sought to evaluate the ACh hypothesis by examining vortioxetine's ability to reverse scopolamine-induced impairments in rodent tests of memory and attention. Additionally, vortioxetine's effects on hippocampal extracellular ACh levels were examined alongside studies of vortioxetine's pharmacokinetic profile. We found that acute vortioxetine reversed scopolamine-induced impairments in social and object recognition memory, but did not alter scopolamine-induced impairments in attention. Acute vortioxetine also induced a modest and short-lived increase in hippocampal ACh levels. However, this short-term effect is at variance with vortioxetine's moderately long brain half life (5.1 hours). Interestingly, subchronic vortioxetine treatment failed to reverse scopolamine-induced social recognition memory deficits and had no effects on basal hippocampal ACh levels. These data suggest that vortioxetine has some effects on memory that could be mediated through cholinergic neurotransmission, however these effects are modest and only seen under acute dosing conditions. These limitations may argue against cholinergic mechanisms being the primary mediator of vortioxetine's cognitive effects, which are observed under chronic dosing conditions in patients with MDD.

  17. Task- and Treatment Length–Dependent Effects of Vortioxetine on Scopolamine-Induced Cognitive Dysfunction and Hippocampal Extracellular Acetylcholine in Rats

    PubMed Central

    Pehrson, Alan L.; Hillhouse, Todd M.; Haddjeri, Nasser; Rovera, Renaud; Porter, Joseph H.; Mørk, Arne; Smagin, Gennady; Song, Dekun; Budac, David; Cajina, Manuel

    2016-01-01

    Major depressive disorder (MDD) is a common psychiatric disorder that often features impairments in cognitive function, and these cognitive symptoms can be important determinants of functional ability. Vortioxetine is a multimodal antidepressant that may improve some aspects of cognitive function in patients with MDD, including attention, processing speed, executive function, and memory. However, the cause of these effects is unclear, and there are several competing theories on the underlying mechanism, notably including regionally-selective downstream enhancement of glutamate neurotransmission and increased acetylcholine (ACh) neurotransmission. The current work sought to evaluate the ACh hypothesis by examining vortioxetine’s ability to reverse scopolamine-induced impairments in rodent tests of memory and attention. Additionally, vortioxetine’s effects on hippocampal extracellular ACh levels were examined alongside studies of vortioxetine’s pharmacokinetic profile. We found that acute vortioxetine reversed scopolamine-induced impairments in social and object recognition memory, but did not alter scopolamine-induced impairments in attention. Acute vortioxetine also induced a modest and short-lived increase in hippocampal ACh levels. However, this short-term effect is at variance with vortioxetine’s moderately long brain half life (5.1 hours). Interestingly, subchronic vortioxetine treatment failed to reverse scopolamine-induced social recognition memory deficits and had no effects on basal hippocampal ACh levels. These data suggest that vortioxetine has some effects on memory that could be mediated through cholinergic neurotransmission, however these effects are modest and only seen under acute dosing conditions. These limitations may argue against cholinergic mechanisms being the primary mediator of vortioxetine′s cognitive effects, which are observed under chronic dosing conditions in patients with MDD. PMID:27402279

  18. Amelioration of scopolamine induced cognitive dysfunction and oxidative stress by Inonotus obliquus - a medicinal mushroom.

    PubMed

    Giridharan, Vijayasree Vayalanellore; Thandavarayan, Rajarajan Amirthalingam; Konishi, Tetsuya

    2011-06-01

    The present study was aimed to investigate the cognitive enhancing and anti-oxidant activities of Inonotus obliquus (Chaga) against scopolamine-induced experimental amnesia. Methanolic extract of Chaga (MEC) at 50 and 100 mg kg (-1)doses were administered orally for 7 days to amnesic mice. Learning and memory was assessed by passive avoidance task (PAT) and Morris water maze (MWM) test. Tacrine (THA, 10 mg kg (-1), orally (p.o)) used as a reference drug. To elucidate the mechanism of the cognitive enhancing activity of MEC, the activities of acetylcholinesterase (AChE), anti-oxidant enzymes, the levels of acetylcholine (ACh) and nitrite of mice brain homogenates were evaluated. MEC treatment for 7 days significantly improved the learning and memory as measured by PAT and MWM paradigms. Further, MEC significantly reduced the oxidative-nitritive stress, as evidenced by a decrease in malondialdehyde and nitrite levels and restored the glutathione and superoxide dismutase levels in a dose dependent manner. In addition, MEC treatment significantly decreased the AChE activity in both the salt and detergent-soluble fraction of brain homogenates. Further, treatment with MEC restored the levels of ACh as did THA. Thus, the significant cognitive enhancement observed in mice after MEC administration is closely related to higher brain anti-oxidant properties and inhibition of AChE activity. These findings stress the critical impact of Chaga, a medicinal mushroom, on the higher brain functions like learning and memory.

  19. Anthriscus nemorosa essential oil inhalation prevents memory impairment, anxiety and depression in scopolamine-treated rats.

    PubMed

    Bagci, Eyup; Aydin, Emel; Ungureanu, Eugen; Hritcu, Lucian

    2016-12-01

    Anthriscus nemorosa (Bieb.) Sprengel is used for medicinal purposes in traditional medicine around the world, including Turkey. Ethnobotanical studies suggest that Anthriscus essential oil could improve memory in Alzheimer's disease. The current study was hypothesized to investigate the beneficial effects of inhaled Anthriscus nemorosa essential oil on memory, anxiety and depression in scopolamine-treated rats. Anthriscus nemorosa essential oil was administered by inhalation in the doses of 1% and 3% for 21 continuous days and scopolamine (0.7mg/kg) was injected intraperitoneally 30min before the behavioral testing. Y-maze and radial arm-maze tests were used for assessing memory processes. Also, the anxiety and depressive responses were studied by elevated plus-maze and forced swimming tests. As expected, the scopolamine alone-treated rats exhibited the following: decrease the percentage of the spontaneous alternation in Y-maze test, increase the number of working and reference memory errors in radial arm-maze test, decrease of the exploratory activity, the percentage of the time spent and the number of entries in the open arm within elevated plus-maze test and decrease of swimming time and increase of immobility time within forced swimming test. However, dual scopolamine and Anthriscus nemorosa essential oil-treated rats showed significant improvement of memory formation and exhibited anxiolytic- and antidepressant-like effects in scopolamine-treated rats. These results suggest that Anthriscus nemorosa essential oil inhalation can prevent scopolamine-induced memory impairment, anxiety and depression.

  20. Cognitive enhancing and antioxidant activity of ethyl acetate soluble fraction of the methanol extract of Hibiscus rosa sinensis in scopolamine-induced amnesia

    PubMed Central

    Nade, Vandana S.; Kanhere, Sampat V.; Kawale, Laxman A.; Yadav, Adhikrao V.

    2011-01-01

    Objective: The objective of the present study was to evaluate the cognitive enhancing and antioxidant activity of Hibiscus rosa sinensis. Materials and Methods: The learning and memory was impaired by administration of scopolamine (1 mg/kg, i.p.) in mice which is associated with altered brain oxidative status. The object recognition test (ORT) and passive avoidance test (PAT) were used to assess cognitive enhancing activity. Animals were treated with an ethyl acetate soluble fraction of the methanol extract of H. sinensis (25, 50 and 100 mg/kg, p.o). Results: The ethyl acetate soluble fraction of the methanol extract of H. sinensis (EASF) attenuated amnesia induced by scopolamine and aging. The discrimination index (DI) was significantly decreased in the aged and scopolamine group in ORT. Pretreatment with EASF significantly increased the DI. In PAT, scopolamine-treated mice exhibited significantly shorter step-down latencies (SDL). EASF treatment showed a significant increase in SDL in young, aged as well as in scopolamine-treated animals. The biochemical analysis of brain revealed that scopolamine treatment increased lipid peroxidation and decreased levels of superoxide dismutase (SOD) and glutathione reductase (GSH). Administration of extract significantly reduced LPO and reversed the decrease in brain SOD and GSH levels. The administration of H. sinensis improved memory in amnesic mice and prevented the oxidative stress associated with scopolamine. The mechanism of such protection of H. sinensis may be due to augmentation of cellular antioxidants. Conclusion: The results of the present study suggested that H. sinensis had a protective role against age and scopolamine-induced amnesia, indicating its utility in management of cognitive disorders. PMID:21572646

  1. Nootropic, neuroprotective and neurotrophic effects of phloretin in scopolamine induced amnesia in mice.

    PubMed

    Ghumatkar, Priya J; Patil, Sachin P; Jain, Pankaj D; Tambe, Rufi M; Sathaye, Sadhana

    2015-08-01

    Phloretin (PHL), a dihydrochalcone flavonoid usually present in the roots and leaves of apple tree. In vitro study on GT1-7 immortalized hypothalamic neurons exposed to amyloid beta (25-35), demonstrated that PHL significantly influenced membrane fluidity and potential. PHL also significantly decreased excitotoxicity by restoring the calcium homeostasis in the same. Thus, PHL proves to be a promising therapeutic moiety which should be further screened in the treatment of Alzheimer's disease. The objective of the present study was to evaluate the nootropic, neuroprotective and neurotrophic roles of PHL in the subacute scopolamine induced amnesia in mice. In this study, mice were pretreated with PHL 2.5mg/kg, 5mg/kg, 10mg/kg and Donepezil (DON) 1mg/kg intraperitoneally (i.p) for 14days. The last 7days of treatment regimen included daily injection of SCP 1.5mg/kg to induce cognitive deficits. Mice were subjected to behavioral analysis. Biochemical estimation of the brain homogenates for acetylcholinesterase and oxidative stress biomarkers were conducted. Furthermore, immunohistochemical analysis for the brain derived neurotrophic factor (BDNF) was carried out particularly in the hippocampus. PHL was found to significantly improve the performance of mice in Morris water maze test (P<0.001) and significantly decreased the acetylcholinesterase activity (P<0.001) at all doses compared to SCP treated mice. Also, PHL significantly elevated the activity of antioxidant enzymes viz. superoxide dismutase, catalase, reduced glutathione levels (P<0.001) and decreased malonaldehyde levels (P<0.001) in comparison with the SCP group. Immunohistochemistry revealed that PHL treatment dose dependently improved BDNF levels in the hippocampus which were found to be significantly depleted (P<0.001) in the SCP group. Additionally, PHL (10mg/kg) significantly enhanced the spatial memory formation (P<0.05) and neurotrophicity (P<0.001) compared to DON (1mg/kg). The aforementioned research

  2. Bone Marrow-Derived Endothelial Progenitor Cells Protect Against Scopolamine-Induced Alzheimer-Like Pathological Aberrations.

    PubMed

    Safar, Marwa M; Arab, Hany H; Rizk, Sherine M; El-Maraghy, Shohda A

    2016-04-01

    Vascular endothelial dysfunction plays a key role in the pathogenesis of Alzheimer's disease (AD). Patients with AD have displayed decreased circulating endothelial progenitor cells (EPCs) which repair and maintain the endothelial function. Transplantation of EPCs has emerged as a promising approach for the management of cerebrovascular diseases including ischemic stroke, however, its impact on AD has been poorly described. Thus, the current study aimed at investigating the effects of bone marrow-derived (BM) EPCs transplantation in repeated scopolamine-induced cognitive impairment, an experimental model that replicates biomarkers of AD. Intravenously transplanted BM-EPCs migrated into the brain of rats and improved the learning and memory deficits. Meanwhile, they mitigated the deposition of amyloid plaques and associated histopathological alterations. At the molecular levels, BM-EPCs blunted the increase of hippocampal amyloid beta protein (Aβ), amyloid precursor protein (APP) and reinstated the Aβ-degrading neprilysin together with downregulation of p-tau and its upstream glycogen synthase kinase-3β (GSK-3β). They also corrected the perturbations of neurotransmitter levels including restoration of acetylcholine and associated esterase along with dopamine, GABA, and the neuroexitatory glutamate. Furthermore, BM-EPCs induced behavioral recovery via boosting of vascular endothelial growth factor (VEGF), nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and its upstream cAMP response element binding (CREB), suppression of the proinflammatory tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), and upregulation of interleukin-10 (IL-10). BM-EPCs also augmented Nrf2 and seladin-1. Generally, these actions were analogous to those exerted by adipose tissue-derived mesenchymal stem cells (AT-MSCs) and the reference anti-Alzheimer donepezil. For the first time, these findings highlight the beneficial actions of BM-EPCs against the memory

  3. Determination of the effectiveness of components of the herbal medicine Toki-Shakuyaku-San and fractions of Angelica acutiloba in improving the scopolamine-induced impairment of rat's spatial cognition in eight-armed radial maze test.

    PubMed

    Hatip-Al-Khatib, Izzettin; Egashira, Nobuaki; Mishima, Kenichi; Iwasaki, Katsunori; Iwasaki, Kiyo; Kurauchi, Kouji; Inui, Keiichiro; Ikeda, Tomoaki; Fujiwara, Michihiro

    2004-09-01

    The improving effects of various components of Toki-Shakuyaku-San (TSS) and fractions isolated from Angelica acutiloba Radix (Toki) on scopolamine-induced spatial memory impairment were investigated in eight-armed radial maze. The scopolamine-induced memory impairment was characterized by prominent increase of error choices in addition to decreased correct choices. Toki, Cnidium officinale Rhizoma (Senkyu), Poria cocos Hoelen (Bukuryo), Alisma orientale Rhizoma (Takusha), and Atractylodes lancea Rhizoma (Sojutsu) increased the correct choices, while only the Toki, Sojutsu, and Takusha decreased the error choices. No effect was produced by Paeonia lactiflora Radix (Shakuyaku). Investigation of effects of fractions isolated from Toki revealed that its activity mainly resided in the butanol layer and its contents of N-methyl-beta-carboline-3-carboxamide and amines. Moreover, the alkaloid, internal and external solutions (containing poly-, di-, and monosaccharides) obtained by dialysis with Visking cellophane tubing also improved the memory. However, no improving properties were detected for methanol and hexanol layers, L-(-)-tryptophan, L-arginine, L-(-)-lysine, and choline chloride. The results showed that the TSS components could improve the reference and working memory impaired by scopolamine. The improving effect of TSS is produced greatly by the Toki component, the activity of which was greatly produced by the fraction extracted by butanol.

  4. Ameliorative effects of amide derivatives of 1,3,4-thiadiazoles on scopolamine induced cognitive dysfunction.

    PubMed

    Kulshreshtha, Akanksha; Piplani, Poonam

    2016-10-21

    The present study reports the effect of amide derivatives of 1,3,4-thiadizoles on scopolamine induced deficit cholinergic neurotransmission and oxidative stress serving as promising leads for the therapeutics of cognitive dysfunction. Fourteen compounds (2c-8d) have been synthesised and evaluated against behavioural alterations using step down passive avoidance protocol and morris water maze and at a dose of 0.5 mg/kg with reference to the standard, Rivastigmine. All the synthesised compounds were evaluated for their in vitro acetylcholinesterase (AChE) inhibition at five different concentrations using mice brain homogenate as the source of the enzyme. Biochemical estimation of markers of oxidative stress (lipid peroxidation, superoxide dismutase, glutathione, plasma nitrite, catalase) has also been carried out to assess the role of synthesised molecules on the oxidative damage induced by scopolamine. The compounds 5c, 6c and 8c displayed appreciable activity with an IC50 value of 3 μM, 3.033 μM and 2.743 μM, respectively towards acetylcholinesterase inhibition. These compounds also decreased scopolamine induced oxidative stress, thus serving as promising leads for the amelioration of oxidative stress induced cognitive decline. The molecular docking study performed to predict the binding mode of the compounds also suggested that these compounds bind appreciably with the amino acids present in the active site of recombinant human acetylcholinesterase (rhAChE). The results indicated that these compounds could be further traversed as inhibitors of AChE and oxidative stress for the treatment of cognitive dysfunction.

  5. Asparagus adscendens root extract enhances cognition and protects against scopolamine induced amnesia: An in-silico and in-vivo studies.

    PubMed

    Pahwa, Priyanka; Goel, Rajesh Kumar

    2016-12-25

    Asparagus adscendens Roxb. commonly known as safed musli and belonging to the Liliaceae family is cultivated mainly in Asian countries. In traditional medicine, safed musli is recommended as nerve tonic and remedy for memory impairment. The present study was aimed to evaluate nootropic and antiamnesic activities of Asparagus adscendens extract (AAE) using in silico and in vivo approach. Phytoconstituents of A. adscendens root reported in literature were subjected to in silico prediction using PASS and Pharmaexpert. The radial arm maze and passive shock avoidance paradigm were employed to evaluate nootropic activity. Subsequently, the anti-amnesic activity was evaluated in scopolamine induced amnesia model. To elucidate the mechanism of nootropic activity, the effect of AAE on the activities of acetylcholinesterase and antioxidant enzymes in the cortex and hippocampus of mice were also evaluated. In silico activity spectrum for all of A. adscendens phytoconstituents exhibited excellent prediction score for nootropic activity. Pretreatment with AAE (50, 100 & 200 mg/kg, i.p.) for 15 days showed significant decrease in working memory error, reference memory error and retrieval latency in radial arm maze and decrease in step down latency in passive shock avoidance paradigm were observed. Further, AAE significantly reduced acetylcholinesterase and oxidative stress parameters in cortex and hippocampus of mice. Thus, in silico and in vivo results suggest that A. adscendens root may exert its nootropic activity through both anti-acetylcholinesterase and antioxidant activities.

  6. Towards an animal model of an antipsychotic drug-resistant cognitive impairment in schizophrenia: scopolamine induces abnormally persistent latent inhibition, which can be reversed by cognitive enhancers but not by antipsychotic drugs.

    PubMed

    Barak, Segev; Weiner, Ina

    2009-03-01

    Schizophrenia symptoms segregate into positive, negative and cognitive, which exhibit differential sensitivity to drugs. Recent efforts to identify treatments targeting cognitive impairments in schizophrenia have directed attention to the cholinergic system for its well documented role in cognition. Relatedly, muscarinic antagonists (e.g. scopolamine) produce an 'antimuscarinic syndrome', characterized by psychosis and cognitive impairments. Latent inhibition (LI) is the poorer conditioning to a stimulus resulting from its non-reinforced pre-exposure. LI indexes the ability to ignore irrelevant stimuli and aberrations of this capacity produced by pro-psychotic agents (e.g. amphetamine, MK-801) are used extensively to model attentional impairments in schizophrenia. We recently showed that LI was disrupted by scopolamine at low doses, and this was reversed by typical and atypical antipsychotic drugs (APDs) and the acetylcholinesterase inhibitor physostigmine. Here, at a higher dose (1.5 mg/kg), scopolamine produced an opposite pole of attentional impairment, namely, attentional perseveration, whereby scopolamine-treated rats persisted in expressing LI under strong conditioning that prevented LI expression in controls. Scopolamine-induced persistent LI was reversed by cholinergic and glycinergic cognitive enhancers (physostigmine and glycine) but was resistant to both typical and atypical APDs (haloperidol and clozapine). The latter sets scopolamine-induced persistent LI apart from scopolamine- and amphetamine-induced disrupted LI, which are reversed by both typical and atypical APDs, as well as from other cases of abnormally persistent LI including MK-801-induced persistent LI, which is reversed by atypical APDs. Thus, scopolamine-induced persistent LI may provide a pharmacological LI model for screening cognitive enhancers that are efficient for the treatment of APD-resistant cognitive impairments in schizophrenia.

  7. Ascorbic acid attenuates scopolamine-induced spatial learning deficits in the water maze.

    PubMed

    Harrison, F E; Hosseini, A H; Dawes, S M; Weaver, S; May, J M

    2009-12-28

    Vitamin C (ascorbate) has important antioxidant functions that can help protect against oxidative stress in the brain and damage associated with neurodegenerative disorders such as Alzheimer's disease. When administered parenterally ascorbate can bypass saturable uptake mechanisms in the gut and thus higher tissue concentrations can be achieved than by oral administration. In the present study we show that ascorbate (125 mg/kg) administered intraperitoneally (i.p.) 1-h before testing, partially attenuated scopolamine-induced (1 mg/kg i.p.) cognitive deficits in Morris water maze performance in young mice. Cumulative search error, but not escape latency nor path length, was significantly improved during acquisition in ascorbate plus scopolamine-treated mice although performance did not equal that of control mice. During the probe trial, scopolamine led to increased search error and chance level of time spent in the platform quadrant, whereas mice pre-treated with ascorbate prior to scopolamine did not differ from control mice on these measures. Ascorbate had no effect on unimpaired, control mice and neither did it reduce the peripheral, activity-increasing effects of scopolamine. Ascorbate alone increased acetylcholinesterase activity in the medial forebrain area but had no effect in cortex or striatum. This change, and its action against the amnestic effects of the muscarinic antagonist scopolamine, suggest that ascorbate may be acting in part via altered cholinergic signaling. However, further investigation is necessary to isolate the cognition-enhancing effects of ascorbate.

  8. Methyllycaconitine- and scopolamine-induced cognitive dysfunction: differential reversal effect by cognition-enhancing drugs

    PubMed Central

    Andriambeloson, Emile; Huyard, Bertrand; Poiraud, Etienne; Wagner, Stéphanie

    2014-01-01

    There is a growing body of evidence pointing to the pivotal role of alpha-7 nicotinic acetylcholine receptor (α7 nAchR) dysfunction in cognitive disorders such as Alzheimer’s disease or schizophrenia. This study was undertaken to establish and characterize an in vivo model for cognitive disorder secondary to the blockade of α7 nAChR by its specific antagonist, methyllycaconitine (MLA). The results show that MLA elicited cognitive dysfunction as assessed by reduced spontaneous alternation of mice in the T-maze. The maximal effect of MLA produced 25–30% reduction in the spontaneous alternation of mice, a level comparable with that induced by the muscarinic antagonism of scopolamine. Donepezil and galantamine fully reversed both MLA and scopolamine-induced cognitive dysfunction. However, the ED50 of donepezil and galantamine was significantly shifted to the left in the MLA- compared to scopolamine-treated mice (0.0005 and 0.002 mg/kg for donepezil; 0.0003 and 0.7 mg/kg for galantamine). Moreover, memantine elicited marked reversion of cognitive dysfunction (up to 70%) in MLA-treated mice while only a weak reversal effect at high dose of memantine (less than 20%) was observed in scopolamine-treated mice. The above findings indicate that MLA-induced cognitive dysfunction in the mouse is highly sensitive and more responsive to the current procognitive drugs than the traditional scopolamine-based assay. Thus, it can be of value for the preclinical screening and profiling of cognition-enhancing drugs. PMID:25505596

  9. CDP-choline attenuates scopolamine induced disruption of prepulse inhibition in rats: involvement of central nicotinic mechanism.

    PubMed

    Uslu, Gulsah; Savci, Vahide; Buyukuysal, Levent R; Goktalay, Gokhan

    2014-05-21

    It has been shown that cholinergic system plays an important role in schizophrenia-associated cognitive deficits, therefore cholinergic drugs are novel targets for the treatment of cognitive deficits seen in schizophrenia. We aimed to test the effects of CDP-choline on sensorimotor gating functioning, which is an important function for the integration of sensory and cognitive information processing and the execution of appropriate motor responses. In this study, prepulse inhibition (PPI) of the acoustic startle reflex was used to test the sensorimotor gating functioning, and the effects of CDP-choline on scopolamine induced PPI disruption were evaluated in rats. Furthermore, the contribution of the cholinergic mechanism in these effects was determined. CDP-choline (75, 250, 500mg/kg) by itself had no effect on the PPI in naïve animals. Scopolamine (0.4mg/kg; s.c.) significantly decreased the PPI levels and intraperitoneal administration of CDP-choline (250mg/kg) attenuated the effects of scopolamine. A non-specific nicotinic receptor antagonist, mecamylamine and an alpha 7 nicotinic receptor (α7-nAChR) antagonist, methyllycaconitine were used to investigate the mechanism underlying the effects of CDP-choline. Mecamylamine (3mg/kg; s.c.), and methyllycaconitine (10μg; i.c.v.) completely blocked the reversal effects of CDP-choline on scopolamine induced disruption of PPI. These results demonstrate that exogenous administration of CDP-choline attenuates scopolamine induced PPI disruption and show that the activation of central α7-nAChR may play a critical role in this effect.

  10. Fucoxanthin, a Marine Carotenoid, Reverses Scopolamine-Induced Cognitive Impairments in Mice and Inhibits Acetylcholinesterase in Vitro.

    PubMed

    Lin, Jiajia; Huang, Ling; Yu, Jie; Xiang, Siying; Wang, Jialing; Zhang, Jinrong; Yan, Xiaojun; Cui, Wei; He, Shan; Wang, Qinwen

    2016-03-25

    Fucoxanthin, a natural carotenoid abundant in edible brown seaweeds, has been shown to possess anti-cancer, anti-oxidant, anti-obesity and anti-diabetic effects. In this study, we report for the first time that fucoxanthin effectively protects against scopolamine-induced cognitive impairments in mice. In addition, fucoxanthin significantly reversed the scopolamine-induced increase of acetylcholinesterase (AChE) activity and decreased both choline acetyltransferase activity and brain-derived neurotrophic factor (BDNF) expression. Using an in vitro AChE activity assay, we discovered that fucoxanthin directly inhibits AChE with an IC50 value of 81.2 μM. Molecular docking analysis suggests that fucoxanthin likely interacts with the peripheral anionic site within AChE, which is in accordance with enzymatic activity results showing that fucoxanthin inhibits AChE in a non-competitive manner. Based on our current findings, we anticipate that fucoxanthin might exhibit great therapeutic efficacy for the treatment of Alzheimer's disease by acting on multiple targets, including inhibiting AChE and increasing BDNF expression.

  11. Scopolamine-induced convulsions in fasted mice after food intake: effects of glucose intake, antimuscarinic activity and anticonvulsant drugs.

    PubMed

    Enginar, Nurhan; Nurten, Asiye; Celik, Pinar Yamantürk; Açikmeşe, Bariş

    2005-09-01

    The present study was performed to further evaluate the contribution of antimuscarinic activity and hypoglycaemia to the development of scopolamine-induced convulsions in fasted mice after food intake. The effects of anticonvulsant drugs on convulsions were also evaluated. Antimuscarinic drugs atropine (3 mg/kg) and biperiden (10 mg/kg) were given intraperitoneally (i.p) to animals fasted for 48 h. Like scopolamine, both drugs induced convulsions after animals were allowed to eat ad libitum. Another group of animals was given glucose (5%) in drinking water during fasting. These animals, although they had normoglycaemic blood levels after fasting, also developed convulsions after treated with scopolamine i.p. (3 mg/kg), atropine (3 mg/kg) or biperiden (10 mg/kg) and allowed to eat ad libitum. Among the drugs studied, only valproate (340 mg/kg), gabapentin (50 mg/kg) and diazepam (2.5 and 5 mg/kg) markedly reduced the incidence of scopolamine-induced convulsions. The present results indicate that antimuscarinic activity, but not hypoglycaemia, underlies these convulsions which do not respond to most of the conventional anticonvulsant drugs.

  12. Cognition Enhancing and Neuromodulatory Propensity of Bacopa monniera Extract Against Scopolamine Induced Cognitive Impairments in Rat Hippocampus.

    PubMed

    Pandareesh, M D; Anand, T; Khanum, Farhath

    2016-05-01

    Cognition-enhancing activity of Bacopa monniera extract (BME) was evaluated against scopolamine-induced amnesic rats by novel object recognition test (NOR), elevated plus maze (EPM) and Morris water maze (MWM) tests. Scopolamine (2 mg/kg body wt, i.p.) was used to induce amnesia in rats. Piracetam (200 mg/kg body wt, i.p.) was used as positive control. BME at three different dosages (i.e., 10, 20 and 40 mg/kg body wt.) improved the impairment induced by scopolamine by increasing the discrimination index of NOR and by decreasing the transfer latency of EPM and escape latency of MWM tests. Our results further elucidate that BME administration has normalized the neurotransmitters (acetylcholine, glutamate, 5-hydroxytryptamine, dopamine, 3,4 dihydroxyphenylacetic acid, norepinephrine) levels that were altered by scopolamine administration in hippocampus of rat brain. BME administration also ameliorated scopolamine effect by down-regulating AChE and up-regulating BDNF, muscarinic M1 receptor and CREB expression in brain hippocampus confirms the potent neuroprotective role and these results are in corroboration with the earlier in vitro studies. BME administration showed significant protection against scopolamine-induced toxicity by restoring the levels of antioxidant and lipid peroxidation. These results indicate that, cognition-enhancing and neuromodulatory propensity of BME is through modulating the expression of AChE, BDNF, MUS-1, CREB and also by altering the levels of neurotransmitters in hippocampus of rat brain.

  13. Fucoxanthin, a Marine Carotenoid, Reverses Scopolamine-Induced Cognitive Impairments in Mice and Inhibits Acetylcholinesterase in Vitro

    PubMed Central

    Lin, Jiajia; Huang, Ling; Yu, Jie; Xiang, Siying; Wang, Jialing; Zhang, Jinrong; Yan, Xiaojun; Cui, Wei; He, Shan; Wang, Qinwen

    2016-01-01

    Fucoxanthin, a natural carotenoid abundant in edible brown seaweeds, has been shown to possess anti-cancer, anti-oxidant, anti-obesity and anti-diabetic effects. In this study, we report for the first time that fucoxanthin effectively protects against scopolamine-induced cognitive impairments in mice. In addition, fucoxanthin significantly reversed the scopolamine-induced increase of acetylcholinesterase (AChE) activity and decreased both choline acetyltransferase activity and brain-derived neurotrophic factor (BDNF) expression. Using an in vitro AChE activity assay, we discovered that fucoxanthin directly inhibits AChE with an IC50 value of 81.2 μM. Molecular docking analysis suggests that fucoxanthin likely interacts with the peripheral anionic site within AChE, which is in accordance with enzymatic activity results showing that fucoxanthin inhibits AChE in a non-competitive manner. Based on our current findings, we anticipate that fucoxanthin might exhibit great therapeutic efficacy for the treatment of Alzheimer’s disease by acting on multiple targets, including inhibiting AChE and increasing BDNF expression. PMID:27023569

  14. Neuroprotective effects of inhaled lavender oil on scopolamine-induced dementia via anti-oxidative activities in rats.

    PubMed

    Hancianu, Monica; Cioanca, Oana; Mihasan, Marius; Hritcu, Lucian

    2013-03-15

    Lavender is used in traditional medicines in Asia, Europe, ancient Greece and Rome, and was mentioned in the Bible and in ancient Jewish texts. Also, lavender is reported to be an effective medical plant in treating inflammation, depression, stress and headache. The present study was undertaken in order to investigate the antioxidant and antiapoptotic activities of the lavender essential oils from Lavandula angustifolia ssp. angustifolia Mill. and Lavandula hybrida Rev. using superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) specific activities, total content of reduced glutathione (GSH), malondialdehyde (MDA) level (lipid peroxidation) and DNA fragmentation assays in male Wistar rats subjected to scopolamine-induced dementia rat model. In scopolamine-treated rats, lavender essential oils showed potent antioxidant and antiapoptotic activities. Subacute exposures (daily, for 7 continuous days) to lavender oils significantly increased antioxidant enzyme activities (SOD, GPX and CAT), total content of reduced GSH and reduced lipid peroxidation (MDA level) in rat temporal lobe homogenates, suggesting antioxidant potential. Also, DNA cleavage patterns were absent in the lavender groups, suggesting antiapoptotic activity. Taken together, our results suggest that antioxidant and antiapoptotic activities of the lavender essential oils are the major mechanisms for their potent neuroprotective effects against scopolamine-induced oxidative stress in the rat brain.

  15. Bis(9)-(-)-nor-meptazinol as a novel dual-binding AChEI potently ameliorates scopolamine-induced cognitive deficits in mice.

    PubMed

    Liu, Ting; Xia, Zheng; Zhang, Wei-Wei; Xu, Jian-rong; Ge, Xin-Xing; Li, Juan; Cui, Yongyao; Qiu, Zhui-Bai; Xu, Jun; Xie, Qiong; Wang, Hao; Chen, Hong-Zhuan

    2013-03-01

    Alzheimer's disease (AD) is a multifaceted neurodegenerative disorder which is characterized by the progressive deterioration of cognition and the emergence of behavioral and psychological symptoms in aging patients. Given that the clinical effectiveness of acetylcholinesterase inhibitors (AChEIs) has still been questioned due to dubious disease-modifying effects, the multi-target directed ligand (MTDL) design has become an emerging strategy for developing new drugs for AD treatment. Bis(9)-(-)-nor-meptazinol (Bis-Mep) was firstly reported by us as a novel MTDL for both potent cholinesterase and amyloid-β aggregation inhibition. In this study, we further explored its AChE inhibition kinetic features and cognitive amelioration. Bis-Mep was found to be a mixed-type inhibitor on electric eel AChE by enzyme kinetic study. Molecular docking revealed that two "water bridges" located at the two wings of Bis-Mep stabilized its interaction with both catalytic and peripheral anionic sites of AChE. Furthermore, subcutaneous administration of Bis-Mep (10, 100 or 1000 ng/kg) significantly reversed the scopolamine-induced memory deficits in a typical bell-shaped dose-response manner. The maximal cognitive amelioration of Bis-Mep was achieved at 100 ng/kg, comparable with the effect of a reference drug Huperzine A at 1 mg/kg and also the relevant AChE inhibition in brain. These findings suggested that Bis-Mep might be a promising dual-binding AChE inhibitor for potential AD therapeutics.

  16. Adenosine A2A receptors are necessary and sufficient to trigger memory impairment in adult mice

    PubMed Central

    Pagnussat, N; Almeida, A S; Marques, D M; Nunes, F; Chenet, G C; Botton, P H S; Mioranzza, S; Loss, C M; Cunha, R A; Porciúncula, L O

    2015-01-01

    Background and Purpose Caffeine (a non-selective adenosine receptor antagonist) prevents memory deficits in aging and Alzheimer’s disease, an effect mimicked by adenosine A2A receptor, but not A1 receptor, antagonists. Hence, we investigated the effects of adenosine receptor agonists and antagonists on memory performance and scopolamine-induced memory impairment in mice. Experimental Approach We determined whether A2A receptors are necessary for the emergence of memory impairments induced by scopolamine and whether A2A receptor activation triggers memory deficits in naïve mice, using three tests to assess short-term memory, namely the object recognition task, inhibitory avoidance and modified Y-maze. Key Results Scopolamine (1.0 mg·kg−1, i.p.) impaired short-term memory performance in all three tests and this scopolamine-induced amnesia was prevented by the A2A receptor antagonist (SCH 58261, 0.1–1.0 mg·kg−1, i.p.) and by the A1 receptor antagonist (DPCPX, 0.2–5.0 mg·kg−1, i.p.), except in the modified Y-maze where only SCH58261 was effective. Both antagonists were devoid of effects on memory or locomotion in naïve rats. Notably, the activation of A2A receptors with CGS 21680 (0.1–0.5 mg·kg−1, i.p.) before the training session was sufficient to trigger memory impairment in the three tests in naïve mice, and this effect was prevented by SCH 58261 (1.0 mg·kg−1, i.p.). Furthermore, i.c.v. administration of CGS 21680 (50 nmol) also impaired recognition memory in the object recognition task. Conclusions and Implications These results show that A2A receptors are necessary and sufficient to trigger memory impairment and further suggest that A1 receptors might also be selectively engaged to control the cholinergic-driven memory impairment. PMID:25939452

  17. PASS assisted prediction and pharmacological evaluation of hesperidin against scopolamine induced amnesia in mice.

    PubMed

    Habibyar, Ahmad Farid; Sharma, Neha; Khurana, Navneet

    2016-10-15

    Alzheimer's disease (AD) is a neurodegenerative disorder that leads to memory impairment. However, the exact etiology of AD is not clear but cholinergic dysfunction and oxidative stress are considered to play an important role in its pathogenesis. Because of this reason, antioxidant compounds are expected to play potential beneficial role in this disease. Among number of antioxidant compounds, hesperidin (HSD) was selected for this study on the basis of its reported antioxidant and neuroprotective effects. Moreover, it has shown higher probable activity value for scavenging free radical along with anti-dementia effects, predicted by PASS online computer program. Current study was designed to evaluate the nootropic and antioxidant effects of HSD. The different groups of animals received scopolamine (2mg/kg) along with co-treamtment of HSD (100, 200mg/kg) and donepezil HCl (3mg/kg) i.p. for consecutive 10 days. Behavioral tests were carried out, 30min after respective treatment on 2nd, 5th and 9th day for memory evaluation. On 10th day of treatment, the animals were sacrificed and the homogenates of brain hippocampus and cortex were used for biochemical estimation. Co-treatment with HSD at both doses significantly reversed the changes in memory and biochemical alterations, induced by scopolamine administration. It can be concluded that HSD has strong memory enhancing and anti-oxidant effects, therefore, it can be considered as a potential candidate for its further pharmacological evaluation for AD-induced dementia.

  18. Sodium Tanshinone IIA Sulfonate Attenuates Scopolamine-Induced Cognitive Dysfunctions via Improving Cholinergic System

    PubMed Central

    Xu, Yi-Jun; Yang, Cong; Li, Lin; Hou, Bo-Nan; Chen, Hui-Fang; Wang, Qi

    2016-01-01

    Sodium Tanshinone IIA sulfonate (STS) is a derivative of Tanshinone IIA (Tan IIA). Tan IIA has been reported to possess neuroprotective effects against Alzheimer's disease (AD). However, whether STS possesses effect on AD remains unclear. This study aims to estimate whether STS could protect against scopolamine- (SCOP-) induced learning and memory deficit in Kunming mice. Morris water maze results showed that oral administration of STS (10 mg/kg and 20 mg/kg) and Donepezil shortened escape latency, increased crossing times of the original position of the platform, and increased the time spent in the target quadrant. STS decreased the activity of acetylcholinesterase (AChE) and increased the activity of choline acetyltransferase (ChAT) in the hippocampus and cortex of SCOP-treated mice. Oxidative stress results showed that STS increased the activity of superoxide dismutase (SOD) and decreased the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) in hippocampus and cortex. In addition, western blot was carried out to detect the expression of apoptosis related proteins (Bcl-2, Bax, and Caspase-3). STS upregulated the protein expression of Bcl-2 and downregulated the proteins expression of Bax and Caspase-3. These results indicated that STS might become a promising therapeutic candidate for attenuating AD-like pathological dysfunction. PMID:27556046

  19. Effect of Gingko biloba extract on scopolamine-induced apoptosis in the hippocampus of rats.

    PubMed

    Jahanshahi, M; Nickmahzar, E G; Babakordi, F

    2013-09-01

    Apoptosis, known as programmed cell death, plays a crucial role in normal development and tissue homeostasis. Apoptosis is also involved in neurodegenerative diseases such as Alzheimer's disease. Amnesia refers to the loss of memory and can also be a warning sign of neurodegenerative diseases. The antioxidant properties of Ginkgo biloba extract was known previously. Therefore, the aim of this study was to examine the effects of Ginkgo biloba extract on the rat's hippocampal apoptotic neurons number after Scopolamine based amnesia. Thirty-six adult male Wistar rats were used. Rats were randomly divided into control, sham, protective and treatment groups. The rats in the sham group received only scopolamine hydrobromide (3 mg/kg) intraperitoneally. The rats in the protective and treatment groups received Ginkgo biloba extract (40, 80 mg/kg) for 7 days intraperitoneally before/after scopolamine injection. Then 48 h after the last injection, the brains of rats were withdrawn and fixed with paraformaldehyde, and then, after histological processing, the slices were stained with the TUNEL kit for apoptotic neurons. Data were compared by the ANOVA Post Hoc Tukey test; P < 0.05 was considered significant. Our results showed that Scopolamine (in the sham group) increased significantly the number of apoptotic neurons in all areas of the hippocampus compared with the control. Whereas, Ginkgo biloba extract reduce the neuronal apoptosis in the hippocampus before and/or after encounter with scopolamine. We concluded that pretreatment and treatment injection of Ginkgo biloba extract can have a protective effect for neurons and it can limit apoptosis in all area of the hippocampus.

  20. The Garrett Lee Smith Memorial Suicide Prevention Program

    ERIC Educational Resources Information Center

    Goldston, David B.; Walrath, Christine M.; McKeon, Richard; Puddy, Richard W.; Lubell, Keri M.; Potter, Lloyd B.; Rodi, Michael S.

    2010-01-01

    In response to calls for greater efforts to reduce youth suicide, the Garrett Lee Smith (GLS) Memorial Act has provided funding for 68 state, territory, and tribal community grants, and 74 college campus grants for suicide prevention efforts. Suicide prevention activities supported by GLS grantees have included education, training programs…

  1. Activation of dopamine D1 receptors in the medial septum improves scopolamine-induced amnesia in the dorsal hippocampus.

    PubMed

    Zarrindast, Mohammad Reza; Ardjmand, Abolfazl; Ahmadi, Shamseddin; Rezayof, Ameneh

    2012-04-01

    In the present study, we investigated the influence of intra-medial septum (intra-MS) injections of dopamine D1 receptor agents on amnesia induced by intra-CA1 injections of a muscarinic acetylcholine receptor antagonist, scopolamine. This study used a step-through inhibitory (passive) avoidance task to assess memory in adult male Wistar rats. The results showed that in the animals that received post-training intra-MS injections of saline, intra-CA1 administrations of scopolamine (0.75, 1, and 2 μg/rat) decreased inhibitory avoidance (IA) memory consolidation as evidenced by a decrease in step-through latency on the test day, which was suggestive of drug-induced amnesia. Post-training intra-MS injections of a dopamine D1 receptor agonist, SKF38393 at doses of 0.1, 0.15, and 0.3 μg/rat had no effect, but at dose of 0.5 μg/rat impaired IA memory consolidation. Interestingly, intra-MS injections of SKF38393 (0.15, 0.3 and 0.5 μg/rat) significantly prevented amnesia induced by intra-CA1 injections of scopolamine (1 μg/rat). Intra-MS injections of a dopamine D1 receptor antagonist, SCH23390 (0.5 and 0.75 μg/rat) by itself impaired IA memory consolidation, and also at dose of 0.75 μg/rat increased amnesia induced by intra-CA1 administrations of an ineffective dose of scopolamine (0.5 μg/rat). Post-training intra-MS injections of ineffective doses of SCH23390 (0.1, 0.3 and 0.5 μg/rat) prevented an effective dose of SKF38393 response to the impaired effect of scopolamine. These results suggest that dopamine D1 receptors in the MS via projection neurons to the hippocampus affect impairment of memory consolidation induced by intra-CA injections of scopolamine.

  2. Resveratrol exerts anti-inflammatory and neuroprotective effects to prevent memory deficits in rats exposed to chronic unpredictable mild stress.

    PubMed

    Yazir, Yusufhan; Utkan, Tijen; Gacar, Nejat; Aricioglu, Feyza

    2015-01-01

    A number of studies have recently focused on the neuroprotective and anti-inflammatory effects of resveratrol. In prior studies, we described its beneficial effects on scopolamine-induced learning deficits in rats. The aim of this study was to investigate the effects of resveratrol on emotional and spatial cognitive functions, neurotropic factor expression, and plasma levels of proinflammatory cytokines in rats exposed to chronic unpredictable mild stress (CUMS), which is known to induce cognitive deficits. Resveratrol (5 or 20mg/kg) was administered intraperitoneally for 35 days. Rats in the CUMS group and in the 5mg/kg resveratrol+CUMS group performed poorly in tasks designed to assess emotional and spatial learning and memory. The 20mg/kg resveratrol+CUMS group showed improved performance compared to the CUMS group. In addition, the CUMS procedure induced lower expression of brain-derived neurotrophic factor and c-Fos in hippocampal CA1 and CA3 and in the amygdala of stressed rats. These effects were reversed by chronic administration of resveratrol (20mg/kg). In addition, plasma levels of tumor necrosis factor-alpha and interleukin-1 beta were increased by CUMS, but were restored to normal by resveratrol. These results indicate that resveratrol significantly attenuates the deficits in emotional learning and spatial memory seen in chronically stressed rats. These effects may be related to resveratrol-mediated changes in neurotrophin factor expression in hippocampus and in levels of proinflammatory cytokines in circulation.

  3. Tempol prevents chronic sleep-deprivation induced memory impairment.

    PubMed

    Alzoubi, Karem H; Khabour, Omar F; Albawaana, Amal S; Alhashimi, Farah H; Athamneh, Rabaa Y

    2016-01-01

    Sleep deprivation is associated with oxidative stress that causes learning and memory impairment. Tempol is a nitroxide compound that promotes the metabolism of many reactive oxygen species (ROS) and has antioxidant and neuroprotective effect. The current study investigated whether chronic administration of tempol can overcome oxidative stress and prevent learning and memory impairment induced by sleep deprivation. Sleep deprivation was induced in rats using multiple platform model. Tempol was administered to rats via oral gavages. Behavioral studies were conducted to test the spatial learning and memory using radial arm water maze. The hippocampus was dissected; antioxidant biomarkers (GSH, GSSG, GSH/GSSG ratio, GPx, SOD, and catalase) were assessed. The result of this project revealed that chronic sleep deprivation impaired both short and long term memory (P<0.05), while tempol treatment prevented such effect. Furthermore, tempol normalized chronic sleep deprivation induced reduction in the hippocampus activity of catalase, GPx, and SOD (P<0.05). Tempol also enhanced the ratio of GSH/GSSG in chronically sleep deprived rats treated with tempol as compared with only sleep deprived rats (P<0.05). In conclusion chronic sleep deprivation induced memory impairment, and treatment with tempol prevented this impairment probably through normalizing antioxidant mechanisms in the hippocampus.

  4. Auraptene consolidates memory, reverses scopolamine-disrupted memory in passive avoidance task, and ameliorates retention deficits in mice

    PubMed Central

    Tabrizian, Kaveh; Yaghoobi, Najmeh Sadat; Iranshahi, Mehrdad; Shahraki, Jafar; Rezaee, Ramin; Hashemzaei, Mahmoud

    2015-01-01

    Objective(s): Auraptene (7-geranyloxycoumarin) (AUR), from Citrus species has shown anti-inflammatory, neuroprotective, and acetylcholinesterase (AChE) and beta-secretase inhibitory effects. Scopolamine is a nonselective muscarinic receptor antagonist which causes short-term memory impairments and is used for inducing animal model of Alzheimer’s disease (AD). This research aimed to investigate the effect of AUR on scopolamine-induced avoidance memory retention deficits in step-through task in mice. Materials and Methods: The effect of four-day pre-training injections of AUR (50, 75, and 100 mg/kg, subcutaneous (SC)) and scopolamine (1 mg/kg, IP), and their co-administration on avoidance memory retention in step-through passive avoidance task, was investigated by measuring the latency to enter to the dark chamber. Results: Pre-training administration of AUR caused significant increase in step-through latency in comparison with control group, 48, 96, and 168 hr after training trial. The findings of this study showed that scopolamine (1 mg/kg, IP, for four consecutive days) impaired passive avoidance memory retention compared to saline-treated animals. Step-through passive avoidance task results showed that AUR markedly reversed scopolamine-induced avoidance memory retention impairments, 24 and 168 hr after training trial in step-through task. Conclusion: Results from co-administration of AUR and scopolamine showed that AUR reversed scopolamine-induced passive avoidance memory retention impairments. PMID:26730337

  5. National Memorial Institute for the Prevention of Terrorism

    NASA Astrophysics Data System (ADS)

    Reimer, Dennis J.; Houghton, Brian K.; Ellis, James O., III

    2003-09-01

    The National Memorial Institute for the Prevention of Terrorism in Oklahoma City is a living memorial to the victims, survivors, family members and rescue workers affected by the April 19, 1995 bombing of the Murrah Federal Building. The Institute conducts research into the development of technologies to counter biological, nuclear and chemical weapons of mass destruction and cyberterrorism, as well as research into the social and political causes and effects of terrorism. This paper describes MIPT funded research in areas of detection, decontamination, personal protective equipment, attack simulations, treatments, awareness, improved public communication during and after an incident, as well as lessons learned from terrorist incidents.

  6. National Memorial Institute for the Prevention of Terrorism

    NASA Astrophysics Data System (ADS)

    Reimer, Dennis J.; Houghton, Brian K.; Powell, Ellen L.

    2004-09-01

    The National Memorial Institute for the Prevention of Terrorism (MIPT) in Oklahoma City is a living memorial to the victims, survivors, family members and rescue workers affected by the April 19, 1995 bombing of the Murrah Federal Building. The Institute conducts research into the development of technologies to counter biological, nuclear and chemical weapons of mass destruction and cyberterrorism, as well as research into the social and political causes and effects of terrorism. This paper describes MIPT funded research in areas of detection, decontamination, personal protective equipment, attack simulations, treatments, awareness, improved public communication during and after an incident, as well as lessons learned from terrorist incidents.

  7. Recovering and preventing loss of detailed memory: differential rates of forgetting for detail types in episodic memory

    PubMed Central

    Bonasia, Kyra; St-Laurent, Marie; Pishdadian, Sara; Winocur, Gordon; Grady, Cheryl; Moscovitch, Morris

    2016-01-01

    Episodic memories undergo qualitative changes with time, but little is known about how different aspects of memory are affected. Different types of information in a memory, such as perceptual detail, and central themes, may be lost at different rates. In patients with medial temporal lobe damage, memory for perceptual details is severely impaired, while memory for central details is relatively spared. Given the sensitivity of memory to loss of details, the present study sought to investigate factors that mediate the forgetting of different types of information from naturalistic episodic memories in young healthy adults. The study investigated (1) time-dependent loss of “central” and “peripheral” details from episodic memories, (2) the effectiveness of cuing with reminders to reinstate memory details, and (3) the role of retrieval in preventing forgetting. Over the course of 7 d, memory for naturalistic events (film clips) underwent a time-dependent loss of peripheral details, while memory for central details (the core or gist of events) showed significantly less loss. Giving brief reminders of the clips just before retrieval reinstated memory for peripheral details, suggesting that loss of details is not always permanent, and may reflect both a storage and retrieval deficit. Furthermore, retrieving a memory shortly after it was encoded prevented loss of both central and peripheral details, thereby promoting retention over time. We consider the implications of these results for behavioral and neurobiological models of retention and forgetting. PMID:26773100

  8. Arctigenin isolated from the seeds of Arctium lappa ameliorates memory deficits in mice.

    PubMed

    Lee, In-Ah; Joh, Eun-Ha; Kim, Dong-Hyun

    2011-09-01

    The seeds of Arctium lappa L. (AL, family Asteraceae), the main constituents of which are arctiin and arctigenin, have been used as an herbal medicine or functional food to treat inflammatory diseases. These main constituents were shown to inhibit acetylcholinesterase (AChE) activity. Arctigenin more potently inhibited AChE activity than arctiin. Arctigenin at doses of 30 and 60 mg/kg (p. o.) potently reversed scopolamine-induced memory deficits by 62 % and 73 %, respectively, in a passive avoidance test. This finding is comparable with that of tacrine (10 mg/kg p. o.). Arctigenin also significantly reversed scopolamine-induced memory deficits in the Y-maze and Morris water maze tests. On the basis of these findings, arctigenin may ameliorate memory deficits by inhibiting AChE.

  9. Neuromodulatory propensity of Bacopa monniera against scopolamine-induced cytotoxicity in PC12 cells via down-regulation of AChE and up-regulation of BDNF and muscarnic-1 receptor expression.

    PubMed

    Pandareesh, M D; Anand, T

    2013-10-01

    Scopolamine is a competitive antagonist of muscarinic acetylcholine receptors, and thus classified as an anti-muscarinic and anti-cholinergic drug. PC12 cell lines possess muscarinic receptors and mimic the neuronal cells. These cells were treated with different concentrations of scopolamine for 24 h and were protected from the cellular damage by pretreatment with Bacopa monniera extract (BME). In current study, we have explored the molecular mechanism of neuromodulatory and antioxidant propensity of (BME) to attenuate scopolamine-induced cytotoxicity using PC12 cells. Our results elucidate that pretreatment of PC12 cells with BME ameliorates the mitochondrial and plasma membrane damage induced by 3 μg/ml scopolamine to 54.83 and 30.30 % as evidenced by MTT and lactate dehydrogenase assays respectively. BME (100 μg/ml) ameliorated scopolamine effect by down-regulating acetylcholine esterase and up-regulating brain-derived neurotropic factor and muscarinic muscarinic-1 receptor expression. BME pretreated cells also showed significant protection against scopolamine-induced toxicity by restoring the levels of antioxidant enzymes and lipid peroxidation. This result indicates that the scopolamine-induced cytotoxicity and neuromodulatory changes were restored with the pretreatment of BME.

  10. Scopolamine-induced convulsions in fasted animals after food intake: sensitivity of C57BL/6J mice and Sprague-Dawley rats.

    PubMed

    Enginar, Nurhan; Nurten, Asiye; Türkmen, Aslı Zengin; Çağla, Büyüklü

    2015-05-01

    Food intake triggers convulsions in fasted BALB/c mice and Wistar albino rats treated with antimuscarinic drugs, scopolamine or atropine. Inbred strain studies have yielded considerable information regarding genetic influences on seizure susceptibility and factors contribute to epileptogenesis in rodents. This study, therefore, investigated sensitivity to antimuscarinic-induced seizures in C57BL/6J mice and Sprague-Dawley rats. Food deprivation for 48h in mice and 52h in rats did not produce strain differences in body weight loss. Fasted animals treated i.p. with 3mg/kg scopolamine developed convulsions after food intake. The incidence of convulsions was indifferent in comparison to BALB/c mice and Wistar albino rats. Number of animals developing stage 5 was more and onset of convulsions was longer in C57BL/6J mice than in BALB/c mice. Strain-related differences in sensitivity to seizures in C57BL/6J mice may need further evaluation for investigating genetic influences on scopolamine-induced seizures.

  11. α-Melanocyte-stimulating hormone ameliorates ocular surface dysfunctions and lesions in a scopolamine-induced dry eye model via PKA-CREB and MEK-Erk pathways.

    PubMed

    Ru, Yusha; Huang, Yue; Liu, Huijuan; Du, Juan; Meng, Zhu; Dou, Zexia; Liu, Xun; Wei, Rui Hua; Zhang, Yan; Zhao, Shaozhen

    2015-12-21

    Dry eye is a highly prevalent, chronic, and multifactorial disease that compromises quality of life and generates socioeconomic burdens. The pathogenic factors of dry eye disease (DED) include tear secretion abnormalities, tear film instability, and ocular surface inflammation. An effective intervention targeting the pathogenic factors is needed to control this disease. Here we applied α-Melanocyte-stimulating hormone (α-MSH) twice a day to the ocular surface of a scopolamine-induced dry eye rat model. The results showed that α-MSH at different doses ameliorated tear secretion, tear film stability, and corneal integrity, and corrected overexpression of proinflammatory factors, TNF-α, IL-1β, and IFN-γ, in ocular surface of the dry eye rats. Moreover, α-MSH, at 10(-4) μg/μl, maintained corneal morphology, inhibited apoptosis, and restored the number and size of conjunctival goblet cells in the dry eye rats. Mechanistically, α-MSH activated both PKA-CREB and MEK-Erk pathways in the dry eye corneas and conjunctivas; pharmacological blockade of either pathway abolished α-MSH's protective effects, suggesting that both pathways are necessary for α-MSH's protection under dry eye condition. The peliotropic protective functions and explicit signaling mechanism of α-MSH warrant translation of the α-MSH-containing eye drop into a novel and effective intervention to DED.

  12. Evaluation of Cucurbita maxima extract against scopolamine-induced amnesia in rats: implication of tumour necrosis factor alpha.

    PubMed

    Jawaid, Talha; Shakya, Ashok K; Siddiqui, Hefazat Hussain; Kamal, Mehnaz

    2014-01-01

    Cucurbita maxima (CM) seed oil is commonly used in Indian folk medicine to treat various ailments. We have investigated the effect of CM seed oil on memory impairment induced by scopolamine in rats. Male adult Wistar rats were administered scopolamine 1 mg/kg body weight, i.p. or 1.25 mg/kg body weight, s.c. to induce memory impairment. The nootropic agent piracetam 100 mg/kg body weight, i.p. and CM seed oil 100 and 200 mg/kg body weight, p.o. were administered daily for five consecutive days. The memory function was evaluated in the Morris water maze (MWM) test, the social recognition test (SRT), the elevated plus maze (EPM) test, and the pole climbing test (PCT). Acetylcholinesterase (AChE) activity and oxidative stress parameters were estimated in the cortex, hippocampus, and cerebellum of the brains after completion of the behavioural studies. The effects of scopolamine on the levels of the tumour necrosis factor alpha (TNF-α) transcript were also investigated. Scopolamine caused memory impairment in all the behavioural paradigms along with a significant increase in the AChE activity and oxidative stress in the brain. Scopolamine also caused a significant increase in the expression of TNF-α in the hippocampus. CM seed oil exhibited antiamnesic activity as indicated by a significant reduction in the latency time in the MWM test and decreased social interaction during trial 2 in the SRT. Further, treatment with CM seed oil significantly decreased the AChE activity and malondialdehyde levels and increased the glutathione level in brain regions. CM seed oil also significantly decreased the expression of TNF-α in the hippocampus. The effect of CM seed oil on behavioural and biochemical parameters was comparable to that observed in rats treated with piracetam. These results indicate that CM seed oil may exert antiamnesic activity which may be attributed to the inhibition of AChE and inflammation as well as its antioxidant activity in the brain.

  13. Studies on effects of Emblica officinalis (Amla) on oxidative stress and cholinergic function in scopolamine induced amnesia in mice.

    PubMed

    Golechha, Mahaveer; Bhatia, Jagriti; Arya, Dharmveer Singh

    2012-01-01

    Emblica officinalis, commonly known as amla, is an important medicinal plant of India. Its fruits have potent antioxidant activity due to the presence of tannoids, tannins, vitamin C and flavonoids. The aim of this study was to investigate the beneficial effect of the hydroalcoholic extract of the fruits of Emblica officinalis (EO) on memory impairment in Swiss albino mice. Scopolamine (1 mg kg(-1), i.p)was administered to induce amnesia and the memory was evaluated by using elevated plus-maze and passive avoidance tests. Piracetam (200 mg kg(-1), i.p.) was used as a standard nootropic agent. The EO extract was administered intraperitoneally in four graded doses (150, 300, 450 and 600 mg kg(-1)) for 7 consecutive days to different groups of mice. The mice were sacrificed on the 8th day following assessment of memory. The brain malondialdehyde (MDA) and glutathione (GSH) as well as acetylcholinesterase (AchE)) activity was determined. It was observed that EO extract reversed the amnesia induced by scopolamine. The mean transfer latency and retention latency in the EO extract 600 mg kg(-1) group vs the vehicle treated scopolamine group was 13.46 sec (p<0.001) and 134.4 sec (p<0.001) vs 23.99 sec and 44.55 sec, respectively. EO extract treatment also significantly (p<0.001) ameliorated the oxidative stress induced by scopolamine administration. The mice brain MDA and GSH levels in the EO extract 600 mg kg(-1) group vs the scopolamine group were 29.95 nmol g(-1) of wet tissue and 51.87 microg g(-1) tissue vs 55.22 nmol g(-1) of wet tissue and 28.33 microg g(-1) tissue, respectively. Further, EO extract (300, 450 and 600 mg kg(-1), i.p) significantly (p<0.001) reversed the rise in brain acetyl cholinesterase (AchE) level induced by scopolamine. The mice brain Ach E levels in the EO extract 600 mg kg(-1) group as compared to the scopolamine group was 70.23 vs 151.49 U mg(-1) protein(-1), respectively. These results suggestthat EO possesses memory enhancing, antioxidant

  14. Prevention of Drug-induced Memory Impairment by Immunopharmacotherapy

    PubMed Central

    Treweek, Jennifer B.; Sun, Chengzao; Mayorov, Alexander V.; Qi, Longwu; Levy, Coree L.; Roberts, Amanda J.; Dickerson, Tobin J.; Janda, Kim D.

    2009-01-01

    One approach to treating drug abuse uses anti-drug antibodies to immunize subjects against the illicit substance rather than administering therapeutics that target the specific CNS site of action. At present, passive vaccination has recognized efficacy in treating certain gross symptoms of drug misuse, namely motor activation, self-administration, and overdose. However, the potential for antibodies to prevent drug-induced changes involving finer cognitive processes, such as benzodiazepine-associated amnesia, remains unexplored. To address this concept, a flunitrazepam hapten was synthesized and employed in the generation of a panel of high affinity monoclonal antibodies. Anti-flunitrazepam mAb RCA3A3 (Kd,app= 200 nM) was tested in a mouse model of passive immunization and subsequent mole-equivalent challenge with flunitrazepam. Not only was flunitrazepam-induced sedation prevented, but immunization also conferred protection to memory consolidation as assessed through contextual and cued fear conditioning paradigms. These results provide evidence that immunopharmacotherapeutic blockade of drug intoxication also preserves complex cognitive function. PMID:18921991

  15. Effects of intra-hippocampal microinjection of vitamin B12 on the orofacial pain and memory impairments induced by scopolamine and orofacial pain in rats.

    PubMed

    Erfanparast, Amir; Tamaddonfard, Esmaeal; Nemati, Shaghayegh

    2017-03-01

    In the present study, we investigated the effects of microinjection of vitamin B12 into the hippocampus on the orofacial pain and memory impairments induced by scopolamine and orofacial pain. In ketamine-xylazine anesthetized rats, the right and left sides of the dorsal hippocampus (CA1) were implanted with two guide cannulas. Orofacial pain was induced by subcutaneous injection of formalin (1.5%, 50μl) into the right vibrissa pad, and the durations of face rubbing were recorded at 3-min blocks for 45min. Morris water maze (MWM) was used for evaluation of learning and memory. Finally, locomotor activity was assessed using an open-field test. Vitamin B12 attenuated both phases of formalin-induced orofacial pain. Prior administration of naloxone and naloxonazine, but not naltrindole and nor-binaltorphimine, prevented this effect. Vitamin B12 and physostigmine decreased latency time as well as traveled distance in Morris water maze. In addition, these chemicals improved scopolamine-induced memory impairment. The memory impairment induced by orofacial pain was improved by vitamin B12 and physostigmine used alone. Naloxone prevented, whereas physostigmine enhanced the memory improving effect of vitamin B12 in the pain-induced memory impairment. All the above-mentioned chemicals did not alter locomotor activity. The results of the present study showed that at the level of the dorsal hippocampus, vitamin B12 modulated orofacial pain through a mu-opioid receptor mechanism. In addition, vitamin B12 contributed to hippocampal cholinergic system in processing of memory. Moreover, cholinergic and opioid systems may be involved in improving effect of vitamin B12 on pain-induced memory impairment.

  16. Performance- and task-dependent effects of the dopamine D1/D5 receptor agonist SKF 38393 on learning and memory in the rat.

    PubMed

    Amico, Francesco; Spowart-Manning, Laura; Anwyl, Roger; Rowan, Michael J

    2007-12-22

    Dopamine D(1)/D(5) receptor agonists may enhance cognition by mimicking dopamine's neurophysiological actions on the processes underlying learning and memory. The present study examined the task- and performance- dependence of the cognitive effects of a partial agonist at dopamine D(1)/D(5) receptors, SKF 38393 [(+/-)-1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol hydrobromide], in rats. Spatial working memory was assessed in a T-maze, spatial reference memory in a water maze and habituation learning in a novel environment, a hole board. The muscarinic acetylcholine receptor antagonist scopolamine (1.5 mg/kg, i.p.) was used to cause an impairment of performance of these learning tasks. Administration of SKF 38393 (6 mg/kg, i.p.) alone had no significant effect on spontaneous alternation in the T-maze, latency to escape to a hidden platform in the water maze or the habituation of spontaneous behaviour in the hole board. In contrast, in scopolamine-treated rats, whereas SKF 38393 prevented the scopolamine-induced deficit in the T-maze, it exacerbated the impairment in the water maze and did not significantly alter the disruption of habituation. These results suggest that dopamine D(1)/D(5) receptor activation has performance- and task-dependent effects on cognitive function.

  17. Effect of olanzapine on scopolamine induced deficits in differential reinforcement of low rate 72s (DRL-72s) schedule in rats: involvement of the serotonergic receptors in restoring the deficits.

    PubMed

    Jayarajan, Pradeep; Nirogi, Ramakrishna; Shinde, Anil

    2013-11-15

    Scopolamine, a non-selective muscarinic receptor antagonist has widespread central nervous system effects. Muscarinic receptors located in the central nervous system play a vital role in the modulation of impulsivity. The objective of the current study was to evaluate the effect of scopolamine on impulsivity using differential-reinforcement-of-low-rate 72-s schedule (DRL-72s) and to demonstrate the involvement of serotonergic receptors in mediating the effect of olanzapine (atypical antipsychotic) on scopolamine induced impulsivity. Scopolamine impaired the performance of the rats trained under DRL-72s schedule. Olanzapine reversed the deficits induced by scopolamine. We evaluated the effect of donepezil (cholinesterase inhibitor), SB-742457 (5-HT6 and 5-HT2a antagonist), and haloperidol (typical antipsychotic) in rats challenged with scopolamine in the DRL-72s schedule to identify the receptor(s) involved in reversing the deficits. SB-742457 partially reversed the deficits, but donepezil and haloperidol did not show any effects on the deficits induced by scopolamine. Olanzapine and SB-742457 shifted the peak location (PkL) towards longer IRT duration, indicating a decrease in motor impulsivity. Modulation of scopolamine-induced impulsivity by olanzapine could be partly due to its antagonistic action at 5-HT2a and 5-HT6 receptors, respectively. Superior effects of olanzapine on impulsivity in schizophrenic patients may be mediated through the antagonism of 5-HT2a and 5-HT6 receptors.

  18. Rosmarinus officinalis L. leaf extract improves memory impairment and affects acetylcholinesterase and butyrylcholinesterase activities in rat brain.

    PubMed

    Ozarowski, Marcin; Mikolajczak, Przemyslaw L; Bogacz, Anna; Gryszczynska, Agnieszka; Kujawska, Malgorzata; Jodynis-Liebert, Jadwiga; Piasecka, Anna; Napieczynska, Hanna; Szulc, Michał; Kujawski, Radoslaw; Bartkowiak-Wieczorek, Joanna; Cichocka, Joanna; Bobkiewicz-Kozlowska, Teresa; Czerny, Boguslaw; Mrozikiewicz, Przemyslaw M

    2013-12-01

    Rosmarinus officinalis L. leaf as part of a diet and medication can be a valuable proposal for the prevention and treatment of dementia. The aim of the study was to assess the effects of subchronic (28-fold) administration of a plant extract (RE) (200 mg/kg, p.o.) on behavioral and cognitive responses of rats linked with acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activity and their mRNA expression level in the hippocampus and frontal cortex. The passive avoidance test results showed that RE improved long-term memory in scopolamine-induced rats. The extract inhibited the AChE activity and showed a stimulatory effect on BuChE in both parts of rat brain. Moreover, RE produced a lower mRNA BuChE expression in the cortex and simultaneously an increase in the hippocampus. The study suggests that RE led to improved long-term memory in rats, which can be partially explained by its inhibition of AChE activity in rat brain.

  19. Exploring the Effect of Ginsenoside Rh1 in a Sleep Deprivation-Induced Mouse Memory Impairment Model.

    PubMed

    Lu, Cong; Shi, Zhe; Dong, Liming; Lv, Jingwei; Xu, Pan; Li, Yinghui; Qu, Lina; Liu, Xinmin

    2017-02-28

    Panax ginseng C.A. Meyer (Araliaceae) has been used in traditional Chinese medicine for enhancing cognition for thousands of years. Ginsenoside Rh1, a constituent of ginseng root, as with other constituents, has memory-improving effects in normal mice and scopolamine-induced amnesic mice. Sleep deprivation (SD) is associated with memory impairment through induction of oxidative stress. The present study investigated the effect of Rh1 against SD-induced cognitive impairment and attempted to define the possible mechanisms involved. Ginsenoside Rh1 (20 μmol/kg; 40 μmol/kg) and modafinil (0.42 g/kg) were administered to the mice intraperitoneally for 23 days. After 14-day SD, locomotor activity was examined using the open field test, and the object location recognition and Morris water maze tests were used to evaluate cognitive ability. The cortex and hippocampus were then dissected and homogenized, and levels and activities of antioxidant defense biomarkers were evaluated to determine the level of oxidative stress. The results revealed that Rh1 prevented cognitive impairment induced by SD, and its ability to reduce oxidative stress in cortex and hippocampus may contribute to the mechanism of action. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Anti-amnesic effect of alkaloid fraction from Lycopodiella cernua (L.) Pic. Serm. on scopolamine-induced memory impairment in mice.

    PubMed

    Chuong, Nguyen Ngoc; Trung, Bui Huu; Luan, Tran Cong; Hung, Tran Manh; Dang, Nguyen Hai; Dat, Nguyen Tien

    2014-07-11

    Lycopodiella cernua (L.) Pic. Serm. (Licopodiaceae) has been used in Vietnamese folk medicine for treating central nervous system conditions. In this study, the alkaloid fraction from the methanol extract of this plant (VLC) was evaluated for in vitro acetylcholinesterase (AChE) inhibitory activity in cognition-relevant brain areas of mice. In in vivo study, the cognitive-enhancing effect of VLC on amnesic mice induced by scopolamine was investigated by assessing a passive avoidance and a Morris water maze test. VLC inhibited AChE activity in mouse frontal cortex, hippocampus and striatum with IC50 values of 26.7, 32.2 and 25.7μg/mL, respectively. Administration of VLC (10, 20, 50 and 100mg/kg, p.o.) significantly reversed cognitive impairments in mice by passive avoidance test. Treating with VLC (50mg/kg) reduced escape latencies in training trials and prolonged swimming times in the target quadrant during the probe trial in the water maze task (P<0.05). These results indicated that L. cernua originated from Vietnam has anti-cholinesterase activity and might be useful for the treatment of cognitive impairment.

  1. Preventive and therapeutic effect of treadmill running on chronic stress-induced memory deficit in rats.

    PubMed

    Radahmadi, Maryam; Alaei, Hojjatallah; Sharifi, Mohammad Reza; Hosseini, Nasrin

    2015-04-01

    Previous results indicated that stress impairs learning and memory. In this research, the effects of preventive, therapeutic and regular continually running activity on chronic stress-induced memory deficit in rats were investigated. 70 male rats were randomly divided into seven groups as follows: Control, Sham, Stress-Rest, Rest-Stress, Stress-Exercise, Exercise-Stress and Exercise-Stress & Exercise groups. Chronic restraint stress was applied 6 h/day for 21days and treadmill running 1 h/day. Memory function was evaluated by the passive avoidance test. The results revealed that running activities had therapeutic effect on mid and long-term memory deficit and preventive effects on short and mid-term memory deficit in stressed rats. Regular continually running activity improved mid and long-term memory compared to Exercise-Stress group. The beneficial effects of exercise were time-dependent in stress conditions. Finally, data corresponded to the possibility that treadmill running had a more important role on treatment rather than on prevention on memory impairment induced by stress.

  2. Memory Inhibition as a Critical Factor Preventing Creative Problem Solving.

    PubMed

    Gómez-Ariza, Carlos J; Del Prete, Francesco; Prieto Del Val, Laura; Valle, Tania; Bajo, M Teresa; Fernandez, Angel

    2016-12-12

    The hypothesis that reduced accessibility to relevant information can negatively affect problem solving in a remote associate test (RAT) was tested by using, immediately before the RAT, a retrieval practice procedure to hinder access to target solutions. The results of 2 experiments clearly showed that, relative to baseline, target words that had been competitors during selective retrieval were much less likely to be provided as solutions in the RAT, demonstrating that performance in the problem-solving task was strongly influenced by the predetermined accessibility status of the solutions in memory. Importantly, this was so even when participants were unaware of the relationship between the memory and the problem-solving procedures in the experiments. This finding is consistent with an inhibitory account of retrieval-induced forgetting effects and, more generally, constitutes support for the idea that the activation status of mental representations originating in a given task (e.g., episodic memory) can unwittingly have significant consequences for a different, unrelated task (e.g., problem solving). (PsycINFO Database Record

  3. Blockade of 5-HT2 Receptor Selectively Prevents MDMA-Induced Verbal Memory Impairment

    PubMed Central

    van Wel, J H P; Kuypers, K P C; Theunissen, E L; Bosker, W M; Bakker, K; Ramaekers, J G

    2011-01-01

    3,4-Methylenedioxymethamphetamine (MDMA) or ‘ecstasy' has been associated with memory deficits during abstinence and intoxication. The human neuropharmacology of MDMA-induced memory impairment is unknown. This study investigated the role of 5-HT2A and 5-HT1A receptors in MDMA-induced memory impairment. Ketanserin is a 5-HT2A receptor blocker and pindolol a 5-HT1A receptor blocker. It was hypothesized that pretreatment with ketanserin and pindolol would protect against MDMA-induced memory impairment. Subjects (N=17) participated in a double-blind, placebo-controlled, within-subject design involving six experimental conditions consisting of pretreatment (T1) and treatment (T2). T1 preceded T2 by 30 min. T1–T2 combinations were: placebo–placebo, pindolol 20 mg–placebo, ketanserin 50 mg–placebo, placebo–MDMA 75 mg, pindolol 20 mg–MDMA 75 mg, and ketanserin 50 mg–MDMA 75 mg. Memory function was assessed at Tmax of MDMA by means of a word-learning task (WLT), a spatial memory task and a prospective memory task. MDMA significantly impaired performance in all memory tasks. Pretreatment with a 5-HT2A receptor blocker selectively interacted with subsequent MDMA treatment and prevented MDMA-induced impairment in the WLT, but not in the spatial and prospective memory task. Pretreatment with a 5-HT1A blocker did not affect MDMA-induced memory impairment in any of the tasks. Together, the results demonstrate that MDMA-induced impairment of verbal memory as measured in the WLT is mediated by 5-HT2A receptor stimulation. PMID:21562484

  4. Piracetam prevents memory deficit induced by postnatal propofol exposure in mice.

    PubMed

    Wang, Yuan-Lin; Li, Feng; Chen, Xin

    2016-05-15

    Postnatal propofol exposure impairs hippocampal synaptic development and memory. However, the effective agent to alleviate the impairments was not verified. In this study, piracetam, a positive allosteric modulator of AMPA receptor was administered following a seven-day propofol regime. Two months after propofol administration, hippocampal long-term potentiation (LTP) and long-term memory decreased, while intraperitoneal injection of piracetam at doses of 100mg/kg and 50mg/kg following last propofol exposure reversed the impairments of memory and LTP. Mechanically, piracetam reversed propofol exposure-induced decrease of BDNF and phosphorylation of mTor. Similar as piracetam, BDNF supplementary also ameliorated propofol-induced abnormalities of synaptic plasticity-related protein expressions, hippocampal LTP and long-term memory. These results suggest that piracetam prevents detrimental effects of propofol, likely via activating BDNF synthesis.

  5. The Effect of Preventive, Therapeutic and Protective Exercises on Hippocampal Memory Mediators in Stressed Rats

    PubMed Central

    Radahmadi, Maryam; Hosseini, Nasrin; Alaei, Hojjatallah; Sharifi, Mohammad Reza

    2016-01-01

    Background Exercise plays a significant role in learning and memory. The present study focuses on the hippocampal corticosterone (CORT), interleukin-1 beta (IL-1β), glucose, and brain-derived neurotrophic factor (BDNF) levels in preventive, therapeutic, and protective exercises in stressful conditions. Methods Forty male rats were randomly divided into four groups: the control group and the preventive, therapeutic, and protective exercise groups. The treadmill running was applied at a speed of 20–21m/min and a chronic stress of 6 hours/day for 21 days. Subsequently, the variables were measured in the hippocampus. Results The findings revealed that the hippocampal CORT levels in the preventive exercise group had a significant enhancement compared to the control group. In the protective and particularly the therapeutic exercise groups, the hippocampal CORT levels declined. Furthermore, the hippocampal BDNF levels in the preventive and the therapeutic exercise groups indicated significantly decreased and increased, respectively, in comparison with the control group. In the preventive exercise group, however, the hippocampal glucose level turned out to be substantially higher than that in the control group. Conclusion It appears that the therapeutic exercise group had the best exercise protocols for improving the hippocampal memory mediators in the stress conditions. By contrast, the preventive exercise group could not improve these mediators that had been altered by stress. It is suggested that exercise time, compared to stress, can be considered as a crucial factor in the responsiveness of memory mediators. PMID:27904422

  6. Inhibition of MDMA-induced increase in cortisol does not prevent acute impairment of verbal memory

    PubMed Central

    Kuypers, KPC; Torre, R; Farre, M; Pujadas, M; Ramaekers, JG

    2013-01-01

    Background Ecstasy use is commonly linked with memory deficits in abstinent ecstasy users. Similar impairments are being found during ecstasy intoxication after single doses of ± 3,4 metylenedioxymethamphetamine (MDMA). The concordance of memory impairments during intoxication and abstinence suggests a similar neuropharmacological mechanism underlying acute and chronic memory impairments. The mechanism underlying this impairment is to date not known. We hypothesized that cortisol might play an important role in this mechanism as cortisol, implicated in the regulation of memory performance, can be brought out of balance by stressors like MDMA. Methods In the present study, we aimed to block the MDMA-induced acute memory defect by giving participants a cortisol synthesis inhibitor (metyrapone) together with a single dose of MDMA. Seventeen polydrug MDMA users entered this placebo-controlled within subject study with four treatment conditions. The treatments consisted of MDMA (75 mg) and metyrapone (750 mg), alone and in combination, and double placebo. Pre-treatment with metyrapone or Placebo occurred 1 h prior to MDMA or Placebo administration. Memory performance was tested at peak drug concentrations by means of several memory tests. Cortisol levels were determined in blood and oral fluid; this served as a control measure to see whether manipulations were effective. Results Main findings indicated that whereas treatment with metyrapone blocked the expected MDMA-induced increase in cortisol levels in blood, it did not prevent the MDMA-induced memory deficit from happening. Conclusion We therefore conclude that MDMA-induced increments in cortisol concentrations are not related to MDMA-induced memory impairments. PMID:22946487

  7. Acute nicotine treatment prevents REM sleep deprivation-induced learning and memory impairment in rat.

    PubMed

    Aleisa, A M; Helal, G; Alhaider, I A; Alzoubi, K H; Srivareerat, M; Tran, T T; Al-Rejaie, S S; Alkadhi, K A

    2011-08-01

    Rapid eye movement (REM) sleep deprivation (SD) is implicated in impairment of spatial learning and memory and hippocampal long-term potentiation (LTP). An increase in nicotine consumption among habitual smokers and initiation of tobacco use by nonsmokers was observed during SD. Although nicotine treatment was reported to attenuate the impairment of learning and memory and LTP associated with several mental disorders, the effect of nicotine on SD-induced learning and memory impairment has not been studied. Modified multiple platform paradigm was used to induce SD for 24 or 48 h during which rats were injected with saline or nicotine (1 mg kg(-1) s.c.) twice a day. In the radial arm water maze (RAWM) task, 24- or 48-h SD significantly impaired learning and short-term memory. In addition, extracellular recordings from CA1 and dentate gyrus (DG) regions of the hippocampus in urethane anesthetized rats showed a significant impairment of LTP after 24- and 48-h SD. Treatment of normal rats with nicotine for 24 or 48 h did not enhance spatial learning and memory or affect magnitude of LTP in the CA1 and DG regions. However, concurrent, acute treatment of rats with nicotine significantly attenuated SD-induced impairment of learning and STM and prevented SD-induced impairment of LTP in the CA1 and DG regions. These results show that acute nicotine treatment prevented the deleterious effect of sleep loss on cognitive abilities and synaptic plasticity.

  8. Dietary CDP-choline supplementation prevents memory impairment caused by impoverished environmental conditions in rats.

    PubMed

    Teather, Lisa A; Wurtman, Richard J

    2005-01-01

    We previously showed that dietary cytidine (5')-diphosphocholine (CDP-choline) supplementation could protect against the development of memory deficits in aging rats. In the present study, younger rats exposed to impoverished environmental conditions and manifesting hippocampal-dependent memory impairments similar to those observed in the aging rodents were given CDP-choline, and its effects on this cognitive deficit were assessed. Male Sprague-Dawley rats reared for 3 mo in impoverished (IC) or enriched environmental (EC) conditions concurrently received either a control diet or a diet supplemented with CDP-choline (approximately 500 mg/kg/d). After 3 mo, rats were trained to perform spatial and cued versions of the Morris water maze, and their rates of acquisition and retention were compared. Impoverished rats exhibited a selective deficit in hippocampal-dependent spatial memory which could be ameliorated by feeding them CDP-choline. The CDP-choline had no memory-enhancing effect in enriched rats, nor did it prevent the memory impairment of impoverished rats if the animals consumed it for the initial or final months instead of for the entire 3-mo period. These findings indicate that long-term dietary CDP-choline supplementation can ameliorate the hippocampal-dependent memory impairment caused by impoverished environmental conditions in rats, and suggest that its actions result, in part, from a long-term effect such as enhanced membrane phosphatide synthesis, an effect shown to require long-term dietary supplementation with CDP-choline.

  9. Dietary CDP-choline supplementation prevents memory impairment caused by impoverished environmental conditions in rats

    PubMed Central

    Teather, Lisa A.; Wurtman, Richard J.

    2005-01-01

    We previously showed that dietary cytidine (5′)-diphosphocholine (CDP-choline) supplementation could protect against the development of memory deficits in aging rats. In the present study, younger rats exposed to impoverished environmental conditions and manifesting hippocampal-dependent memory impairments similar to those observed in the aging rodents were given CDP-choline, and its effects on this cognitive deficit were assessed. Male Sprague-Dawley rats reared for 3 mo in impoverished (IC) or enriched environmental (EC) conditions concurrently received either a control diet or a diet supplemented with CDP-choline (∼500 mg/kg/d). After 3 mo, rats were trained to perform spatial and cued versions of the Morris water maze, and their rates of acquisition and retention were compared. Impoverished rats exhibited a selective deficit in hippocampal-dependent spatial memory which could be ameliorated by feeding them CDP-choline. The CDP-choline had no memory-enhancing effect in enriched rats, nor did it prevent the memory impairment of impoverished rats if the animals consumed it for the initial or final months instead of for the entire 3-mo period. These findings indicate that long-term dietary CDP-choline supplementation can ameliorate the hippocampal-dependent memory impairment caused by impoverished environmental conditions in rats, and suggest that its actions result, in part, from a long-term effect such as enhanced membrane phosphatide synthesis, an effect shown to require long-term dietary supplementation with CDP-choline. PMID:15647594

  10. Influence of the Melissa officinalis Leaf Extract on Long-Term Memory in Scopolamine Animal Model with Assessment of Mechanism of Action

    PubMed Central

    Ozarowski, Marcin; Mikolajczak, Przemyslaw L.; Piasecka, Anna; Kachlicki, Piotr; Kujawski, Radoslaw; Bogacz, Anna; Bartkowiak-Wieczorek, Joanna; Szulc, Michal; Kaminska, Ewa; Kujawska, Malgorzata; Jodynis-Liebert, Jadwiga; Gryszczynska, Agnieszka; Opala, Bogna; Lowicki, Zdzislaw; Seremak-Mrozikiewicz, Agnieszka; Czerny, Boguslaw

    2016-01-01

    Melissa officinalis (MO, English: lemon balm, Lamiaceae), one of the oldest and still most popular aromatic medicinal plants, is used in phytomedicine for the prevention and treatment of nervous disturbances. The aim of our study was to assess the effect of subchronic (28-fold) administration of a 50% ethanol extract of MO leaves (200 mg/kg, p.o.) compared with rosmarinic acid (RA, 10 mg/kg, p.o.) and huperzine A (HU, 0.5 mg/kg, p.o.) on behavioral and cognitive responses in scopolamine-induced rats. The results were linked with acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and beta-secretase (BACE-1) mRNA levels and AChE and BuChE activities in the hippocampus and frontal cortex of rats. In our study, MO and HU, but not RA, showed an improvement in long-term memory. The results were in line with mRNA levels, since MO produced a decrease of AChE mRNA level by 52% in the cortex and caused a strong significant inhibition of BACE1 mRNA transcription (64% in the frontal cortex; 50% in the hippocampus). However, the extract produced only an insignificant inhibition of AChE activity in the frontal cortex. The mechanisms of MO action are probably more complicated, since its role as a modulator of beta-secretase activity should be taken into consideration. PMID:27239217

  11. Influence of the Melissa officinalis Leaf Extract on Long-Term Memory in Scopolamine Animal Model with Assessment of Mechanism of Action.

    PubMed

    Ozarowski, Marcin; Mikolajczak, Przemyslaw L; Piasecka, Anna; Kachlicki, Piotr; Kujawski, Radoslaw; Bogacz, Anna; Bartkowiak-Wieczorek, Joanna; Szulc, Michal; Kaminska, Ewa; Kujawska, Malgorzata; Jodynis-Liebert, Jadwiga; Gryszczynska, Agnieszka; Opala, Bogna; Lowicki, Zdzislaw; Seremak-Mrozikiewicz, Agnieszka; Czerny, Boguslaw

    2016-01-01

    Melissa officinalis (MO, English: lemon balm, Lamiaceae), one of the oldest and still most popular aromatic medicinal plants, is used in phytomedicine for the prevention and treatment of nervous disturbances. The aim of our study was to assess the effect of subchronic (28-fold) administration of a 50% ethanol extract of MO leaves (200 mg/kg, p.o.) compared with rosmarinic acid (RA, 10 mg/kg, p.o.) and huperzine A (HU, 0.5 mg/kg, p.o.) on behavioral and cognitive responses in scopolamine-induced rats. The results were linked with acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and beta-secretase (BACE-1) mRNA levels and AChE and BuChE activities in the hippocampus and frontal cortex of rats. In our study, MO and HU, but not RA, showed an improvement in long-term memory. The results were in line with mRNA levels, since MO produced a decrease of AChE mRNA level by 52% in the cortex and caused a strong significant inhibition of BACE1 mRNA transcription (64% in the frontal cortex; 50% in the hippocampus). However, the extract produced only an insignificant inhibition of AChE activity in the frontal cortex. The mechanisms of MO action are probably more complicated, since its role as a modulator of beta-secretase activity should be taken into consideration.

  12. Memory

    MedlinePlus

    ... it has to decide what is worth remembering. Memory is the process of storing and then remembering this information. There are different types of memory. Short-term memory stores information for a few ...

  13. Betaine prevents homocysteine-induced memory impairment via matrix metalloproteinase-9 in the frontal cortex.

    PubMed

    Kunisawa, K; Nakashima, N; Nagao, M; Nomura, T; Kinoshita, S; Hiramatsu, M

    2015-10-01

    Betaine plays important roles that include acting as a methyl donor and converting homocysteine (Hcy) to methionine. Elevated plasma Hcy levels are known as hyperhomocysteinemia (HHcy) and contribute to impairments of learning and memory. Although it is commonly known that betaine plays an important role in Hcy metabolism, the effects of betaine on Hcy-induced memory impairment have not been investigated. Previously, we demonstrated the beneficial effects of betaine on acute stress and lipopolysaccharide-induced memory impairment. In the present study, we investigated whether betaine ameliorates Hcy-induced memory impairment and the underlying mechanisms of this putative effect. Mice were treated with Hcy (0.162mg/kg, s.c.) twice a day for nine days, and betaine (25mg/kg, s.c.) was administered 30min before the Hcy injections. The memory functions were evaluated using a spontaneous alternation performance test (Y-maze) at seven days and a step-down type passive avoidance test (SD) at nine and ten days after Hcy injection. We found that betaine suppressed the memory impairment induced by repeated Hcy injections. However, the blood concentrations of Hcy were significantly increased in the Hcy-treated mice immediately after the passive avoidance test, and betaine did not prevent this increase. Furthermore, Hcy induces redox stress in part by activating matrix metalloproteinase-9 (MMP-9), which leads to BBB dysfunction. Therefore, we tested whether betaine affected MMP-9 activity. Interestingly, treatment with betaine significantly inhibited Hcy-induced MMP-9 activity in the frontal cortex but not in the hippocampus after acute Hcy injection. These results suggest that the changes in MMP-9 activity after betaine treatment might have been partially responsible for the amelioration of the memory deficits and that MMP-9 might be a candidate therapeutic target for HHcy.

  14. Memory.

    ERIC Educational Resources Information Center

    McKean, Kevin

    1983-01-01

    Discusses current research (including that involving amnesiacs and snails) into the nature of the memory process, differentiating between and providing examples of "fact" memory and "skill" memory. Suggests that three brain parts (thalamus, fornix, mammilary body) are involved in the memory process. (JN)

  15. Recovering and Preventing Loss of Detailed Memory: Differential Rates of Forgetting for Detail Types in Episodic Memory

    ERIC Educational Resources Information Center

    Sekeres, Melanie J.; Bonasia, Kyra; St-Laurent, Marie; Pishdadian, Sara; Winocur, Gordon; Grady, Cheryl; Moscovitch, Morris

    2016-01-01

    Episodic memories undergo qualitative changes with time, but little is known about how different aspects of memory are affected. Different types of information in a memory, such as perceptual detail, and central themes, may be lost at different rates. In patients with medial temporal lobe damage, memory for perceptual details is severely impaired,…

  16. Chronic administration of quercetin prevent spatial learning and memory deficits provoked by chronic stress in rats.

    PubMed

    Mohammadi, Hadis Said; Goudarzi, Iran; Lashkarbolouki, Taghi; Abrari, Kataneh; Elahdadi Salmani, Mahmoud

    2014-08-15

    There are several reports that cognitive impairment is observed in stress related disorders and chronic stress impairs learning and memory. However, very few studies have looked into the possible ways of preventing this stress-induced deficit. This research study was conducted to evaluate the effects of quercetin, a natural flavonoid, with strong antioxidant and free radical scavenger properties, on chronic stress induced learning and memory deficits and oxidative stress in hippocampus. For chronic stress, rats were restrained daily for 6h/day (from 9:00 to 15:00) for 21 days in well-ventilated plexiglass tubes without access to food and water. The animals were injected with quercetin or vehicle 60 min before restraint stress over a period of 21 days. Then, rats trained with six trials per day for 6 consecutive days in the water maze. On day 28, a probe test was done to measure memory retention. In addition, oxidative stress markers in the hippocampus were evaluated. Results of this study demonstrated that chronic stress exposure rats exhibited higher escape latency during training trials and reduced time spent in target quadrant, higher escape location latency and average proximity in probe trial test. Quercetin (50mg/kg) treatment during restraint stress (21 days) markedly decreased escape latency and increased time spent in target quadrant during Morris water maze task. In comparison to vehicle treated group, chronic-stress group had significantly higher malondialdehyde (MDA) levels, significantly higher superoxide dismutase (SOD) activity and significantly lower glutathione peroxidase (GPx) activity in the hippocampus. Quercetin treatment caused a significant decrease in the hippocampus MDA levels and improves SOD and GPx activities in stressed animals. Finally, quercetin significantly decreased plasma corticosterone levels in stressed animals. Based on results of this study, chronic stress has detrimental effects on learning and memory and quercetin treatment

  17. Lycium barbarum polysaccharides prevent memory and neurogenesis impairments in scopolamine-treated rats.

    PubMed

    Chen, Weiwei; Cheng, Xiang; Chen, Jinzhong; Yi, Xin; Nie, Dekang; Sun, Xiaohui; Qin, Jianbing; Tian, Meiling; Jin, Guohua; Zhang, Xinhua

    2014-01-01

    Lycium barbarum is used both as a food additive and as a medicinal herb in many countries, and L. barbarum polysaccharides (LBPs), a major cell component, are reported to have a wide range of beneficial effects including neuroprotection, anti-aging and anticancer properties, and immune modulation. The effects of LBPs on neuronal function, neurogenesis, and drug-induced learning and memory deficits have not been assessed. We report the therapeutic effects of LBPs on learning and memory and neurogenesis in scopolamine (SCO)-treated rats. LBPs were administered via gastric perfusion for 2 weeks before the onset of subcutaneous SCO treatment for a further 4 weeks. As expected, SCO impaired performance in novel object and object location recognition tasks, and Morris water maze. However, dual SCO- and LBP-treated rats spent significantly more time exploring the novel object or location in the recognition tasks and had significant shorter escape latency in the water maze. SCO administration led to a decrease in Ki67- or DCX-immunoreactive cells in the dentate gyrus and damage of dendritic development of the new neurons; LBP prevented these SCO-induced reductions in cell proliferation and neuroblast differentiation. LBP also protected SCO-induced loss of neuronal processes in DCX-immunoreactive neurons. Biochemical investigation indicated that LBP decreased the SCO-induced oxidative stress in hippocampus and reversed the ratio Bax/Bcl-2 that exhibited increase after SCO treatment. However, decrease of BDNF and increase of AChE induced by SCO showed no response to LBP administration. These results suggest that LBPs can prevent SCO-induced cognitive and memory deficits and reductions in cell proliferation and neuroblast differentiation. Suppression of oxidative stress and apoptosis may be involved in the above effects of LBPs that may be a promising candidate to restore memory functions and neurogenesis.

  18. Lycium barbarum Polysaccharides Prevent Memory and Neurogenesis Impairments in Scopolamine-Treated Rats

    PubMed Central

    Chen, Jinzhong; Yi, Xin; Nie, Dekang; Sun, Xiaohui; Qin, Jianbing; Tian, Meiling; Jin, Guohua; Zhang, Xinhua

    2014-01-01

    Lycium barbarum is used both as a food additive and as a medicinal herb in many countries, and L. barbarum polysaccharides (LBPs), a major cell component, are reported to have a wide range of beneficial effects including neuroprotection, anti-aging and anticancer properties, and immune modulation. The effects of LBPs on neuronal function, neurogenesis, and drug-induced learning and memory deficits have not been assessed. We report the therapeutic effects of LBPs on learning and memory and neurogenesis in scopolamine (SCO)-treated rats. LBPs were administered via gastric perfusion for 2 weeks before the onset of subcutaneous SCO treatment for a further 4 weeks. As expected, SCO impaired performance in novel object and object location recognition tasks, and Morris water maze. However, dual SCO- and LBP-treated rats spent significantly more time exploring the novel object or location in the recognition tasks and had significant shorter escape latency in the water maze. SCO administration led to a decrease in Ki67- or DCX-immunoreactive cells in the dentate gyrus and damage of dendritic development of the new neurons; LBP prevented these SCO-induced reductions in cell proliferation and neuroblast differentiation. LBP also protected SCO-induced loss of neuronal processes in DCX-immunoreactive neurons. Biochemical investigation indicated that LBP decreased the SCO-induced oxidative stress in hippocampus and reversed the ratio Bax/Bcl-2 that exhibited increase after SCO treatment. However, decrease of BDNF and increase of AChE induced by SCO showed no response to LBP administration. These results suggest that LBPs can prevent SCO-induced cognitive and memory deficits and reductions in cell proliferation and neuroblast differentiation. Suppression of oxidative stress and apoptosis may be involved in the above effects of LBPs that may be a promising candidate to restore memory functions and neurogenesis. PMID:24505383

  19. Lipopolysaccharide-induced memory impairment in rats is preventable using 7-nitroindazole.

    PubMed

    Anaeigoudari, Akbar; Shafei, Mohammad Naser; Soukhtanloo, Mohammad; Sadeghnia, Hamid Reza; Reisi, Parham; Beheshti, Farimah; Mohebbati, Reza; Mousavi, Seyed Mojtaba; Hosseini, Mahmoud

    2015-09-01

    Inflammation and oxidative stress have important roles in memory impairment. The effect of 7-nitroindazole (7NI) on lipopolysaccharide (LPS)-induced memory impairment was investigated. Rats were used, divided into four groups that were treated as follows: (1) control (saline); (2) LPS; (3) 7NI-LPS; and (4) 7NI before passive avoidance (PA). In the LPS group, the latency for entering the dark compartment was shorter than in the controls (p < 0.01 and p < 0.001); while in the 7NI-LPS group, it was longer than in the LPS group (p < 0.01 and p < 0.001). Malondialdehyde (MDA) and nitric oxide (NO) metabolite concentrations in the brain tissues of the LPS group were higher than in the controls (p < 0.001 and p < 0.05); while in the 7NI-LPS group, they were lower than in the LPS group (p < 0.001 and p < 0.05, respectively). The thiol content in the brain of the LPS group was lower than in the controls (p < 0.001); while in the 7NI-LPS group, it was higher than in the LPS group (p < 0.001). It is suggested that brain tissue oxidative damage and NO elevation have a role in the deleterious effects of LPS on memory retention that are preventable using 7NI.

  20. Intranasal Insulin Prevents Anesthesia-Induced Spatial Learning and Memory Deficit in Mice

    PubMed Central

    Zhang, Yongli; Dai, Chun-ling; Chen, Yanxing; Iqbal, Khalid; Liu, Fei; Gong, Cheng-Xin

    2016-01-01

    Elderly individuals are at increased risk of cognitive decline after anesthesia. General anesthesia is believed to be a risk factor for Alzheimer’s disease (AD). At present, there is no treatment that can prevent anesthesia-induced postoperative cognitive dysfunction. Here, we treated mice with daily intranasal administration of insulin (1.75 U/day) for one week before anesthesia induced by intraperitoneal injection of propofol and maintained by inhalation of sevoflurane for 1 hr. We found that the insulin treatment prevented anesthesia-induced deficit in spatial learning and memory, as measured by Morris water maze task during 1–5 days after exposure to anesthesia. The insulin treatment also attenuated anesthesia-induced hyperphosphorylation of tau and promoted the expression of synaptic proteins and insulin signaling in the brain. These findings show a therapeutic potential of intranasal administration of insulin before surgery to reduce the risk of anesthesia-induced cognitive decline and AD. PMID:26879001

  1. Exercise Prevents Memory Impairment Induced by Arsenic Exposure in Mice: Implication of Hippocampal BDNF and CREB.

    PubMed

    Sun, Bao-Fei; Wang, Qing-Qing; Yu, Zi-Jiang; Yu, Yan; Xiao, Chao-Lun; Kang, Chao-Sheng; Ge, Guo; Linghu, Yan; Zhu, Jun-De; Li, Yu-Mei; Li, Qiang-Ming; Luo, Shi-Peng; Yang, Dang; Li, Lin; Zhang, Wen-Yan; Tian, Guang

    2015-01-01

    High concentrations of arsenic, which can be occasionally found in drinking water, have been recognized as a global health problem. Exposure to arsenic can disrupt spatial memory; however, the underlying mechanism remains unclear. In the present study, we tested whether exercise could interfere with the effect of arsenic exposure on the long-term memory (LTM) of object recognition in mice. Arsenic (0, 1, 3, and 10 mg/ kg, i.g.) was administered daily for 12 weeks. We found that arsenic at dosages of 1, 3, and 10 mg/kg decreased body weight and increased the arsenic content in the brain. The object recognition LTM (tested 24 h after training) was disrupted by 3 mg/ kg and 10 mg/ kg, but not 1 mg/ kg arsenic exposure. Swimming exercise also prevented LTM impairment induced by 3 mg/ kg, but not with 10 mg/ kg, of arsenic exposure. The expression of brain-derived neurotrophic factor (BDNF) and phosphorylated cAMP-response element binding protein (pCREB) in the CA1 and dentate gyrus areas (DG) of the dorsal hippocampus were decreased by 3 mg/ kg and 10 mg/ kg, but not by 1 mg/ kg, of arsenic exposure. The decrease in BDNF and pCREB in the CA1 and DG induced by 3 mg/ kg, but not 10 mg/ kg, of arsenic exposure were prevented by swimming exercise. Arsenic exposure did not affect the total CREB expression in the CA1 or DG. Taken together, these results indicated that swimming exercise prevented the impairment of object recognition LTM induced by arsenic exposure, which may be mediated by BDNF and CREB in the dorsal hippocampus.

  2. Exercise Prevents Memory Impairment Induced by Arsenic Exposure in Mice: Implication of Hippocampal BDNF and CREB

    PubMed Central

    Yu, Zi-Jiang; Yu, Yan; Xiao, Chao-Lun; Kang, Chao-Sheng; Ge, Guo; Linghu, Yan; Zhu, Jun-De; Li, Yu-Mei; Li, Qiang-Ming; Luo, Shi-Peng; Yang, Dang; Li, Lin; Zhang, Wen-Yan; Tian, Guang

    2015-01-01

    High concentrations of arsenic, which can be occasionally found in drinking water, have been recognized as a global health problem. Exposure to arsenic can disrupt spatial memory; however, the underlying mechanism remains unclear. In the present study, we tested whether exercise could interfere with the effect of arsenic exposure on the long-term memory (LTM) of object recognition in mice. Arsenic (0, 1, 3, and 10 mg/ kg, i.g.) was administered daily for 12 weeks. We found that arsenic at dosages of 1, 3, and 10 mg/kg decreased body weight and increased the arsenic content in the brain. The object recognition LTM (tested 24 h after training) was disrupted by 3 mg/ kg and 10 mg/ kg, but not 1 mg/ kg arsenic exposure. Swimming exercise also prevented LTM impairment induced by 3 mg/ kg, but not with 10 mg/ kg, of arsenic exposure. The expression of brain-derived neurotrophic factor (BDNF) and phosphorylated cAMP-response element binding protein (pCREB) in the CA1 and dentate gyrus areas (DG) of the dorsal hippocampus were decreased by 3 mg/ kg and 10 mg/ kg, but not by 1 mg/ kg, of arsenic exposure. The decrease in BDNF and pCREB in the CA1 and DG induced by 3 mg/ kg, but not 10 mg/ kg, of arsenic exposure were prevented by swimming exercise. Arsenic exposure did not affect the total CREB expression in the CA1 or DG. Taken together, these results indicated that swimming exercise prevented the impairment of object recognition LTM induced by arsenic exposure, which may be mediated by BDNF and CREB in the dorsal hippocampus. PMID:26368803

  3. Methylphenidate prevents high-fat diet (HFD)-induced learning/memory impairment in juvenile mice.

    PubMed

    Kaczmarczyk, Melissa M; Machaj, Agnieszka S; Chiu, Gabriel S; Lawson, Marcus A; Gainey, Stephen J; York, Jason M; Meling, Daryl D; Martin, Stephen A; Kwakwa, Kristin A; Newman, Andrew F; Woods, Jeffrey A; Kelley, Keith W; Wang, Yanyan; Miller, Michael J; Freund, Gregory G

    2013-09-01

    The prevalence of childhood obesity has risen dramatically and coincident with this upsurge is a growth in adverse childhood psychological conditions including impulsivity, depression, anxiety and attention deficit/hyperactive disorder (ADHD). Due to confounds that exist when determining causality of childhood behavioral perturbations, controversy remains as to whether overnutrition and/or childhood obesity is important. Therefore, we examined juvenile mice to determine if biobehaviors were impacted by a short-term feeding (1-3wks) of a high-fat diet (HFD). After 1wk of a HFD feeding, mouse burrowing and spontaneous wheel running were increased while mouse exploration of the open quadrants of a zero maze, perfect alternations in a Y-maze and recognition of a novel object were impaired. Examination of mouse cortex, hippocampus and hypothalamus for dopamine and its metabolites demonstrated increased homovanillic acid (HVA) concentrations in the hippocampus and cortex that were associated with decreased cortical BDNF gene expression. In contrast, pro-inflammatory cytokine gene transcripts and serum IL-1α, IL-1β, TNF-α and IL-6 were unaffected by the short-term HFD feeding. Administration to mice of the psychostimulant methylphenidate prevented HFD-dependent impairment of learning/memory. HFD learning/memory impairment was not inhibited by the anti-depressants desipramine or reboxetine nor was it blocked in IDO or IL-1R1 knockout mice. In sum, a HFD rapidly impacts dopamine metabolism in the brain appearing to trigger anxiety-like behaviors and learning/memory impairments prior to the onset of weight gain and/or pre-diabetes. Thus, overnutrition due to fats may be central to childhood psychological perturbations such as anxiety and ADHD.

  4. Dehydroevodiamine·HCl enhances cognitive function in memory-impaired rat models

    PubMed Central

    Shin, Ki Young

    2017-01-01

    Progressive memory impairment such as that associated with depression, stroke, and Alzheimer's disease (AD) can interfere with daily life. In particular, AD, which is a progressive neurodegenerative disorder, prominently features a memory and learning impairment that is related to changes in acetylcholine and abnormal β-amyloid (Aβ) deposition in the brain. In the present study, we investigated the effects of dehydroevodiamine·HCl (DHED) on cognitive improvement and the related mechanism in memory-impaired rat models, namely, a scopolamine-induced amnesia model and a Aβ1-42-infused model. The cognitive effects of DHED were measured using a water maze test and a passive avoidance test in the memory-impaired rat models. The results demonstrate that DHED (10 mg/kg, p.o.) and Donepezil (1 mg/kg, p.o.) ameliorated the spatial memory impairment in the scopolamine-induced amnestic rats. Moreover, DHED significantly improved learning and memory in the Aβ1-42-infused rat model. Furthermore, the mechanism of these behavioral effects of DHED was investigated using a cell viability assay, reactive oxygen species (ROS) measurement, and intracellular calcium measurement in primary cortical neurons. DHED reduced neurotoxicity and the production of Aβ-induced ROS in primary cortical neurons. In addition, similar to the effect of MK801, DHED decreased intracellular calcium levels in primary cortical neurons. Our results suggest that DHED has strong protective effects against cognitive impairments through its antioxidant activity and inhibition of neurotoxicity and intracellular calcium. Thus, DHED may be an important therapeutic agent for memory-impaired symptoms. PMID:28066141

  5. Physical exercise prevents short and long-term deficits on aversive and recognition memory and attenuates brain oxidative damage induced by maternal deprivation.

    PubMed

    Neves, Ben-Hur; Menezes, Jefferson; Souza, Mauren Assis; Mello-Carpes, Pâmela B

    2015-12-01

    It is known from previous research that physical exercise prevents long-term memory deficits induced by maternal deprivation in rats. But we could not assume similar effects of physical exercise on short-term memory, as short- and long-term memories are known to result from some different memory consolidation processes. Here we demonstrated that, in addition to long-term memory deficit, the short-term memory deficit resultant from maternal deprivation in object recognition and aversive memory tasks is also prevented by physical exercise. Additionally, one of the mechanisms by which the physical exercise influences the memory processes involves its effects attenuating the oxidative damage in the maternal deprived rats' hippocampus and prefrontal cortex.

  6. Vitamin E prevents high-fat high-carbohydrates diet-induced memory impairment: the role of oxidative stress.

    PubMed

    Alzoubi, Karem H; Khabour, Omar F; Salah, Heba A; Hasan, Zuheir

    2013-07-02

    Memory and learning are impaired by imbalanced diet consumption. High-fat high-carbohydrate diet (HFCD) induces oxidative stress, which results in neuronal damage and interference with synaptic transmission; hence, a decline in cognitive function. Vitamin E is a fat soluble antioxidant that is believed to have positive effects on learning and memory. In this study, we tested the hypothesis that chronic administration of vitamin E prevents learning and memory impairment induced by HFCD. In addition, possible molecular targets for HFCD, and vitamin E that lead to cognitive effects were examined. Vitamin E and/or HFCD were concurrently administered to animals for 6 weeks. Thereafter, behavioral studies were conducted to test the spatial learning and memory using radial arm water maze (RAWM). Additionally, brain derived neurotrophic factor (BDNF) level and antioxidant markers were assessed in the hippocampus. The results of this project revealed that HFCD impairs both short-term and long-term memories (p<0.05). The administration of vitamin E prevented the memory impairment induced by HFCD consumption (p<0.05). The consumption of HFCD reduced activities of hippocampal superoxide dismutase (SOD) and catalase (p<0.05); whereas the levels of thiobarbituric acid reactive substances (TBARS) and oxidized glutathione (GSSG) were elevated (p<0.05). The administration of vitamin E normalized the effect of HFCD on the oxidative stress markers. None of the treatments induced changes in the levels of BDNF or glutathione peroxidase (GPx). In conclusion, HFCD induces memory impairment, and the administration of vitamin E prevented this impairment probably through normalizing antioxidant mechanisms in the hippocampus.

  7. Short-term blueberry-enriched antioxidant diet prevents and reverses object recognition memory loss in aged rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objective Previously, four months of a blueberry-enriched (BB) antioxidant diet prevented impaired object recognition memory in aged rats. Experiment 1 determined whether one and two-month BB diets would have a similar effect and whether the benefits would disappear promptly after terminating the d...

  8. Comparative studies on the effects of the nootropic drugs adafenoxate, meclofenoxate and piracetam, and of citicholine on scopolamine-impaired memory, exploratory behavior and physical capabilities (experiments on rats and mice).

    PubMed

    Petkov, V D; Mosharrof, A H; Petkov, V V

    1988-01-01

    The effects of adafenoxate (Adf), meclofenoxate (Mf), piracetam (Pc), and citicholine (CCh) on scopolamine (Scop)--impaired memory and exploratory behavior (experiments on rats) and on physical capabilities (experiments on mice) were studied. In the experiments with scopolamine (2 mg/kg i.p.) we used the step-through passive avoidance method to determine the memory changes. In the case of single treatment with the drugs tested scopolamine was injected immediately after training and Adf, Mf, and CCh at doses of 20 and 100 mg/kg and Pc at a dose of 100 mg/kg were administered immediately after scopolamine. In the case of multiple administration the drugs were applied at the same doses for 7 days before training. Scopolamine was injected immediately after training. Retention tests were given 3 and 24 hours later. All the four drugs tested prevented to a large extent or completely the scopolamine-induced retrograde amnesia. However, significant quantitative differences in the antiamnestic effects of the drugs tested were observed. The effects of the four drugs on exploratory behavior were tested in the Opto Varimex apparatus. After 7-day treatment with the drugs at the doses utilized, the behavior of experimental animals was observed for 10 min, checking out the changes in the frequency of rearing, ambulation, and rotation. Only Adf at a dose of 50 mg/kg significantly decreased rearing and ambulation frequencies; this effect was considered to be an expression of accelerated habituation. The physical capabilities of mice were studied, using the method of treadmill (revolving drum activity cage) training. Before the experiment the mice received orally Adf, Mf, and Pc at a dose of 100 mg/kg or were injected intraperitoneally with CCh at doses of 50 and 100 mg/kg once daily for 7 days. The number of revolutions of the drum cages was counted for 4 hours. Only Pc significantly increased the physical capabilities of mice and much delayed the occurrence of fatigue.

  9. Memories.

    ERIC Educational Resources Information Center

    Brand, Judith, Ed.

    1998-01-01

    This theme issue of the journal "Exploring" covers the topic of "memories" and describes an exhibition at San Francisco's Exploratorium that ran from May 22, 1998 through January 1999 and that contained over 40 hands-on exhibits, demonstrations, artworks, images, sounds, smells, and tastes that demonstrated and depicted the biological,…

  10. The context counts: congruent learning and testing environments prevent memory retrieval impairment following stress.

    PubMed

    Schwabe, Lars; Wolf, Oliver T

    2009-09-01

    Stress before retention testing impairs memory, whereas memory performance is enhanced when the learning context is reinstated at retrieval. In the present study, we examined whether the negative impact of stress before memory retrieval can be attenuated when memory is tested in the same environmental context as that in which learning took place. Subjects learned a 2-D object location task in a room scented with vanilla. Twenty-four hours later, they were exposed to stress or a control condition before memory for the object location task was assessed in a cued-recall test, either in the learning context or in a different context (unfamiliar room without the odor). Stress impaired memory when assessed in the unfamiliar context, but not when assessed in the learning context. These results suggest that the detrimental effects of stress on memory retrieval can be abolished when a distinct learning context is reinstated at test.

  11. Central noradrenergic depletion by DSP-4 prevents stress-induced memory impairments in the object recognition task.

    PubMed

    Scullion, G A; Kendall, D A; Sunter, D; Marsden, C A; Pardon, M-C

    2009-12-01

    Environmental stress produces adverse affects on memory in humans and rodents. Increased noradrenergic neurotransmission is a major component of the response to stress and noradrenaline (NA) plays an important role in modulating processes involved in learning and memory. The present study investigated the effect of NA depletion on stress-induced changes on memory performance in the mouse. Central NA depletion was induced using the selective neurotoxin N-(2-chloroethyl)-N-ethyl-2 bromobenzylamine (DSP-4) and verified by high performance liquid chromatography (HPLC). A novel cage stress procedure involving exposure to a new clean cage for 1 h per day, 4 days per week for 4 weeks, was used to produce stress-induced memory deficits measured using the object recognition task. 50 mg/kg DSP-4 produced large and sustained reductions in NA levels in the frontal cortex and hippocampus measured 24 h, 1 week and 5 weeks after treatment. Four weeks of exposure to novel cage stress induced a memory deficit in the object recognition task which was prevented by DSP-4 pre-treatment (50 mg/kg 1 week before the commencement of stress).These findings indicate that chronic environmental stress adversely affects recognition memory and that this effect is, in part, mediated by the noradrenergic stress response. The implication of these findings is that drugs targeting the noradrenergic system to reduce over-activity may be beneficial in the treatment of stress-related mental disorders such as post-traumatic stress disorder or anxiety in which memory is affected.

  12. Preventive effect of theanine intake on stress-induced impairments of hippocamapal long-term potentiation and recognition memory.

    PubMed

    Tamano, Haruna; Fukura, Kotaro; Suzuki, Miki; Sakamoto, Kazuhiro; Yokogoshi, Hidehiko; Takeda, Atsushi

    2013-06-01

    Theanine, γ-glutamylethylamide, is one of the major amino acid components in green tea. On the basis of the preventive effect of theanine intake after birth on mild stress-induced attenuation of hippocamapal CA1 long-term potentiation (LTP), the present study evaluated the effect of theanine intake after weaning on stress-induced impairments of LTP and recognition memory. Young rats were fed water containing 0.3% theanine for 3 weeks after weaning and subjected to water immersion stress for 30min, which was more severe than tail suspension stress for 30s used previously. Serum corticosterone levels were lower in theanine-administered rats than in the control rats even after exposure to stress. CA1 LTP induced by a 100-Hz tetanus for 1s was inhibited in the presence of 2-amino-5-phosphonovalerate (APV), an N-methyl-d-aspartate (NMDA) receptor antagonist, in hippocampal slices from the control rats and was attenuated by water immersion stress. In contrast, CA1 LTP was not significantly inhibited in the presence of APV in hippocampal slices from theanine-administered rats and was not attenuated by the stress. Furthermore, object recognition memory was impaired in the control rats, but not in theanine-administered rats. The present study indicates the preventive effect of theanine intake after weaning on stress-induced impairments of hippocampal LTP and recognition memory. It is likely that the modification of corticosterone secretion after theanine intake is involved in the preventive effect.

  13. Dietary CDP-Choline Supplementation Prevents Memory Impairment Caused by Impoverished Environmental Conditions in Rats

    ERIC Educational Resources Information Center

    Teather, Lisa A.; Wurtman, Richard J.

    2005-01-01

    The authors previously showed that dietary cytidine (5')-diphosphocholine (CDP-choline) supplementation could protect against the development of memory deficits in aging rats. In the present study, younger rats exposed to impoverished environmental conditions and manifesting hippocampal-dependent memory impairments similar to those observed in the…

  14. Caffeine consumption prevents diabetes-induced memory impairment and synaptotoxicity in the hippocampus of NONcZNO10/LTJ mice.

    PubMed

    Duarte, João M N; Agostinho, Paula M; Carvalho, Rui A; Cunha, Rodrigo A

    2012-01-01

    Diabetic conditions are associated with modified brain function, namely with cognitive deficits, through largely undetermined processes. More than understanding the underlying mechanism, it is important to devise novel strategies to alleviate diabetes-induced cognitive deficits. Caffeine (a mixed antagonist of adenosine A(1) and A(2A) receptors) emerges as a promising candidate since caffeine consumption reduces the risk of diabetes and effectively prevents memory deficits caused by different noxious stimuli. Thus, we took advantage of a novel animal model of type 2 diabetes to investigate the behavioural, neurochemical and morphological modifications present in the hippocampus and tested if caffeine consumption might prevent these changes. We used a model closely mimicking the human type 2 diabetes condition, NONcNZO10/LtJ mice, which become diabetic at 7-11 months when kept under an 11% fat diet. Caffeine (1 g/l) was applied in the drinking water from 7 months onwards. Diabetic mice displayed a decreased spontaneous alternation in the Y-maze accompanied by a decreased density of nerve terminal markers (synaptophysin, SNAP25), mainly glutamatergic (vesicular glutamate transporters), and increased astrogliosis (GFAP immunoreactivity) compared to their wild type littermates kept under the same diet. Furthermore, diabetic mice displayed up-regulated A(2A) receptors and down-regulated A(1) receptors in the hippocampus. Caffeine consumption restored memory performance and abrogated the diabetes-induced loss of nerve terminals and astrogliosis. These results provide the first evidence that type 2 diabetic mice display a loss of nerve terminal markers and astrogliosis, which is associated with memory impairment; furthermore, caffeine consumption prevents synaptic dysfunction and astrogliosis as well as memory impairment in type 2 diabetes.

  15. Voluntary Running Prevents Progressive Memory Decline and Increases Adult Hippocampal Neurogenesis and Growth Factor Expression After Whole-Brain Irradiation

    PubMed Central

    Wong-Goodrich, Sarah J.E.; Pfau, Madeline L.; Flores, Catherine T.; Fraser, Jennifer A.; Williams, Christina L.; Jones, Lee W.

    2010-01-01

    Whole-brain irradiation (WBI) therapy produces progressive learning and memory deficits in patients with primary or secondary brain tumors. Exercise enhances memory and adult hippocampal neurogenesis in the intact brain, so we hypothesized that exercise may be an effective treatment to alleviate consequences of WBI. Previous studies using animal models to address this issue have yielded mixed results and have not examined potential molecular mechanisms. We investigated the short- and long-term effects of WBI on spatial learning and memory retention, and determined whether voluntary running after WBI aids recovery of brain and cognitive function. Forty adult female C57Bl/6 mice given a single dose of 5 Gy or sham WBI were trained 2.5 weeks and up to four months after WBI in a Barnes maze. Half of the mice received daily voluntary wheel access starting one month after sham- or WBI. Daily running following WBI prevented the marked decline in spatial memory retention observed months after irradiation. Bromodeoxyuridine (BrdU) immunolabeling and ELISA indicated that this behavioral rescue was accompanied by a partial restoration of newborn BrdU+/NeuN+ neurons in the dentate gyrus and increased hippocampal expression of brain-derived vascular endothelial growth factor and insulin-like growth factor, and occurred despite irradiation-induced elevations in hippocampal pro-inflammatory cytokines. WBI in adult mice produced a progressive memory decline consistent with what has been reported in cancer patients receiving WBI therapy. Our findings show that running can abrogate this memory decline and aid recovery of adult hippocampal plasticity, thus highlighting exercise as a potential therapeutic intervention. PMID:20884629

  16. Maternal administration of melatonin prevents spatial learning and memory deficits induced by developmental ethanol and lead co-exposure.

    PubMed

    Soleimani, Elham; Goudarzi, Iran; Abrari, Kataneh; Lashkarbolouki, Taghi

    2017-05-01

    Melatonin is a radical scavenger with the ability to remove reactive oxidant species. There is report that co-exposure to lead and ethanol during developmental stages induces learning and memory deficits and oxidative stress. Here, we studied the effect of melatonin, with strong antioxidant properties, on memory deficits induced by lead and ethanol co-exposure and oxidative stress in hippocampus. Pregnant rats in lead and ethanol co-exposure group received lead acetate of 0.2% in distilled drinking water and ethanol (4g/kg) by oral gavages once daily from the 5th day of gestation until weaning. Rats received 10mg/kg melatonin by oral gavages. On postnatal days (PD) 30, rats trained with six trials per day for 6 consecutive days in the water maze. On day 37, a probe test was done and oxidative stress markers in the hippocampus were evaluated. Results demonstrated lead and ethanol co-exposed rats exhibited higher escape latency during training trials and reduced time spent in target quadrant, higher escape location latency in probe trial test and had significantly higher malondialdehyde (MDA) levels, significantly lower superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities in the hippocampus. Melatonin treatment could improve memory deficits, antioxidants activity and reduced MDA levels in the hippocampus. We conclude, co-exposure to lead and ethanol impair memory and melatonin can prevent from it by oxidative stress modulation.

  17. Estradiol prevents ozone-induced increases in brain lipid peroxidation and impaired social recognition memory in female rats.

    PubMed

    Guevara-Guzmán, R; Arriaga, V; Kendrick, K M; Bernal, C; Vega, X; Mercado-Gómez, O F; Rivas-Arancibia, S

    2009-03-31

    There is increasing concern about the neurodegenerative and behavioral consequences of ozone pollution in industrialized urban centers throughout the world and that women may be more susceptible to brain neurodegenerative disorders. In the present study we have investigated the effects of chronic (30 or 60 days) exposure to ozone on olfactory perception and memory and on levels of lipid peroxidation, alpha and beta estrogen receptors and dopamine beta-hydroxylase in the olfactory bulb in ovariectomized female rats. The ability of 17beta-estradiol to prevent these effects was then assessed. Results showed that ozone exposure for 30 or 60 days impaired formation/retention of a selective olfactory recognition memory 120 min after exposure to a juvenile stimulus animal with the effect at 60 days being significantly greater than at 30 days. They also showed impaired speed in locating a buried chocolate reward after 60 days of ozone exposure indicating some loss of olfactory perception. These functional impairments could all be prevented by coincident estradiol treatment. In the olfactory bulb, levels of lipid peroxidation were increased at both 30- and 60-day time-points and numbers of cells with immunohistochemical staining for alpha and beta estrogen receptors, and dopamine beta-hydroxylase were reduced as were alpha and beta estrogen receptor protein levels. These effects were prevented by estradiol treatment. Oxidative stress damage caused by chronic exposure to ozone does therefore impair olfactory perception and social recognition memory and may do so by reducing noradrenergic and estrogen receptor activity in the olfactory bulb. That these effects can be prevented by estradiol treatment suggests increased susceptibility to neurodegenerative disorders in aging women may be contributed to by reduced estrogen levels post-menopause.

  18. Naringin and Rutin Alleviates Episodic Memory Deficits in Two Differentially Challenged Object Recognition Tasks

    PubMed Central

    Ramalingayya, Grandhi Venkata; Nampoothiri, Madhavan; Nayak, Pawan G.; Kishore, Anoop; Shenoy, Rekha R.; Mallikarjuna Rao, Chamallamudi; Nandakumar, Krishnadas

    2016-01-01

    Background: Cognitive decline or dementia is a debilitating problem of neurological disorders such as Alzheimer's and Parkinson's disease, including special conditions like chemobrain. Dietary flavonoids proved to be efficacious in delaying the incidence of neurodegenerative diseases. Two such flavonoids, naringin (NAR) and rutin (RUT) were reported to have neuroprotective potential with beneficial effects on spatial and emotional memories in particular. However, the efficacy of these flavonoids is poorly understood on episodic memory, which comprises an important form of autobiographical memory. Objective: This study objective is to evaluate NAR and RUT to reverse time-delay-induced long-term and scopolamine-induced short-term episodic memory deficits in Wistar rats. Materials and Methods: We have evaluated both short-term and long-term episodic memory forms using novel object recognition task. Open field paradigm was used to assess locomotor activity for any confounding influence on memory assessment. Donepezil was used as positive control and was effective in both models at 1 mg/kg, i.p. Results: Animals treated with NAR and RUT at 50 and 100 mg/kg, p.o. spent significantly more time exploring novel object compared to familiar one, whereas control animals spent almost equal time with both objects in choice trial. NAR and RUT dose-dependently increased recognition and discriminative indices in time-induced long-term as well as scopolamine-induced short-term episodic memory deficit models without interfering with the locomotor activity. Conclusion: We conclude that, NAR and RUT averted both short- and long-term episodic memory deficits in Wistar rats, which may be potential interventions for neurodegenerative diseases as well as chemobrain condition. SUMMARY Incidence of Alzheimer's disease is increasing globally and the current therapy is only symptomatic. Curative treatment is a major lacuna. NAR and RUT are natural flavonoids proven for their pleiotropic

  19. Ilex latifolia Prevents Amyloid β Protein (25-35)-Induced Memory Impairment by Inhibiting Apoptosis and Tau Phosphorylation in Mice.

    PubMed

    Kim, Joo Youn; Lee, Hong Kyu; Jang, Ji Yeon; Yoo, Jae Kuk; Seong, Yeon Hee

    2015-12-01

    Ilex latifolia Thunb. (Aquifoliaceae), a Chinese bitter tea called "kudingcha," has been widely consumed as a health beverage and found to possess antioxidant, antidiabetic, antihypertensive, anti-inflammatory, and anti-ischemic activities. The aim of the present study was to investigate the neuroprotective effects of an ethanol extract of I. latifolia against amyloid β protein (Aβ)-induced memory impairment in mice and neurotoxicity in cultured rat cortical neurons. Memory impairment in mice was induced by intracerebroventricular injection of 15 nmol Aβ (25-35) and measured by the passive avoidance test and Morris water maze test. Chronic administration of I. latifolia (25-100 mg/kg, p.o.) significantly prevented Aβ (25-35)-induced memory loss. I. latifolia also prevented the decrease of glutathione concentrations, increased lipid peroxidation, expression of phosphorylated tau (p-tau), and changes in apoptosis-associated proteins in the memory-impaired mouse brain. Exposure of cultured cortical neurons to 10 μM Aβ (25-35) for 36 h induced neuronal apoptotic death. The neuronal cell death, elevation of intracellular Ca(2+) concentration, generation of reactive oxygen species, and expression of proapoptotic proteins caused by Aβ (25-35) in the cultured neurons were inhibited by treatment with I. latifolia (1-50 μg/mL). These results suggest that I. latifolia may have a possible therapeutic role in managing cognitive impairment associated with Alzheimer's disease. The underlying mechanism might involve the antiapoptotic effects mediated by antioxidant activity and inhibition of p-tau formation.

  20. Chicoric acid supplementation prevents systemic inflammation-induced memory impairment and amyloidogenesis via inhibition of NF-κB.

    PubMed

    Liu, Qian; Chen, Yuwei; Shen, Chun; Xiao, Yating; Wang, Yutang; Liu, Zhigang; Liu, Xuebo

    2016-12-21

    Chicoric acid (CA), a natural phenolic acid extracted from chicory and the echinacea (purple coneflower) plant (Echinacea purpurea), has been regarded as a nutraceutical that has powerful antioxidant and antiobesity activities. We investigated the inhibitory effects of CA on systemic inflammation-induced neuroinflammation, amyloidogenesis, and cognitive impairment. C57BL/6J mice were treated with 0.05% CA in the drinking water for 45 d. The mice were then treated by intraperitoneal injection of LPS (lipopolysaccharide). It was found that CA prevented LPS-induced memory impairment and neuronal loss through behavioral tests and histological examination. Furthermore, amyloidogenesis in the CNS was detected. The results showed that CA prevented LPS-induced increases in β-amyloid (1-42 specific) (Aβ1-42) accumulation, levels of amyloid precursor protein, and neuronal β-secretase 1 (BACE1), as well as the equilibrium cholinergic system in mouse brain. Moreover, CA down-regulated LPS-induced glial overactivation by inhibiting the MAPK and NF-κB pathway. Consequently, CA reduced the levels of NF-κB transcriptionally regulated inflammatory mediators and cytokines such as iNOS, cyclooxygenase-2 (COX-2), IL-1β, and TNF-α in both mouse brain and BV2 microglial cells. These results demonstrated that CA alleviated memory impairment and amyloidogenesis triggered by LPS through suppressing NF-κB transcriptional pathway, suggesting that CA might be a plausible therapeutic intervention for neuroinflammation-related diseases such as Alzheimer disease.-Liu, Q., Chen, Y., Shen, C., Xiao, Y., Wang, Y., Liu, Z., Liu, X. Chicoric acid supplementation prevents systemic inflammation-induced memory impairment and amyloidogenesis via inhibition of NF-κB.

  1. Intensification of long-term memory deficit by chronic stress and prevention by nicotine in a rat model of Alzheimer's disease.

    PubMed

    Alkadhi, Karim A; Srivareerat, Marisa; Tran, Trinh T

    2010-11-01

    Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cholinergic dysfunction and deposition of beta-amyloid (Aβ) in regions of the brain associated with learning and memory. The sporadic nature and late onset of most AD cases suggests that aside from biological determinants, environmental factors such as stress may also play a role in the progression of the disease. Behavioral and molecular studies were utilized to evaluate the effects of chronic nicotine treatment in the prevention of impairment of long-term memory. The rat model of AD was induced by i.c.v. osmotic pump infusion of Aβ peptides. Chronic psychosocial stress and chronic nicotine treatment were instituted for 6weeks. Spatial memory testing in the Radial Arm Water Maze revealed that, although stress, by itself, did not affect long-term memory, the combination of chronic stress and Aβ infusion impaired long-term memory significantly more than Aβ peptides infusion alone. Chronic nicotine treatment completely prevented Aβ- and stress/Aβ combination-induced memory impairment. Furthermore, molecular findings in hippocampal CA1 region of stress/Aβ rats indicated marked reduction in the protein levels of phosphorylated cAMP response element binding (p-CREB) and calcium-calmodulin-dependent protein kinase IV (CaMKIV), with significant increases in the levels of brain-derived neurotrophic factor (BDNF). These disturbances in signaling pathways, which may be the underlying mechanisms of impairment of long-term memory in these rats, were totally prevented by chronic nicotine treatment.

  2. Intranasal MSC-derived A1-exosomes ease inflammation, and prevent abnormal neurogenesis and memory dysfunction after status epilepticus.

    PubMed

    Long, Qianfa; Upadhya, Dinesh; Hattiangady, Bharathi; Kim, Dong-Ki; An, Su Yeon; Shuai, Bing; Prockop, Darwin J; Shetty, Ashok K

    2017-04-10

    Status epilepticus (SE), a medical emergency that is typically terminated through antiepileptic drug treatment, leads to hippocampus dysfunction typified by neurodegeneration, inflammation, altered neurogenesis, as well as cognitive and memory deficits. Here, we examined the effects of intranasal (IN) administration of extracellular vesicles (EVs) secreted from human bone marrow-derived mesenchymal stem cells (MSCs) on SE-induced adverse changes. The EVs used in this study are referred to as A1-exosomes because of their robust antiinflammatory properties. We subjected young mice to pilocarpine-induced SE for 2 h and then administered A1-exosomes or vehicle IN twice over 24 h. The A1-exosomes reached the hippocampus within 6 h of administration, and animals receiving them exhibited diminished loss of glutamatergic and GABAergic neurons and greatly reduced inflammation in the hippocampus. Moreover, the neuroprotective and antiinflammatory effects of A1-exosomes were coupled with long-term preservation of normal hippocampal neurogenesis and cognitive and memory function, in contrast to waned and abnormal neurogenesis, persistent inflammation, and functional deficits in animals receiving vehicle. These results provide evidence that IN administration of A1-exosomes is efficient for minimizing the adverse effects of SE in the hippocampus and preventing SE-induced cognitive and memory impairments.

  3. Lipopolysaccharide-Induced Spatial Memory and Synaptic Plasticity Impairment Is Preventable by Captopril

    PubMed Central

    Abareshi, Azam; Anaeigoudari, Akbar; Norouzi, Fatemeh; Shafei, Mohammad Naser; Khazaei, Majid

    2016-01-01

    Introduction. Renin-angiotensin system has a role in inflammation and also is involved in many brain functions such as learning, memory, and emotion. Neuroimmune factors have been proposed as the contributors to the pathogenesis of memory impairments. In the present study, the effect of captopril on spatial memory and synaptic plasticity impairments induced by lipopolysaccharide (LPS) was investigated. Methods. The rats were divided and treated into control (saline), LPS (1 mg/kg), LPS-captopril (LPS-Capto; 50 mg/kg captopril before LPS), and captopril groups (50 mg/kg) before saline. Morris water maze was done. Long-term potentiation (LTP) from CA1 area of hippocampus was assessed by 100 Hz stimulation in the ipsilateral Schaffer collateral pathway. Results. In the LPS group, the spent time and traveled path to reach the platform were longer than those in the control, while, in the LPS-Capto group, they were shorter than those in the LPS group. Moreover, the slope and amplitude of field excitatory postsynaptic potential (fEPSP) decreased in the LPS group, as compared to the control group, whereas, in the LPS-Capto group, they increased compared to the LPS group. Conclusion. The results of the present study showed that captopril improved the LPS-induced memory and LTP impairments induced by LPS in rats. Further investigations are required in order to better understand the exact responsible mechanism(s). PMID:27830176

  4. Original nootropic drug noopept prevents memory deficit in rats with muscarinic and nicotinic receptor blockade.

    PubMed

    Radionova, K S; Belnik, A P; Ostrovskaya, R U

    2008-07-01

    Antiamnesic activity of Noopept was studied on the original three-way model of conditioned passive avoidance response, which allows studying spatial component of memory. Cholinoceptor antagonists of both types (scopolamine and mecamylamine) decreased entry latency and reduced the probability for selection of the safe compartment. Noopept abolished the antiamnesic effect of cholinoceptor antagonists and improved spatial preference.

  5. Chronic Microdose Lithium Treatment Prevented Memory Loss and Neurohistopathological Changes in a Transgenic Mouse Model of Alzheimer's Disease.

    PubMed

    Nunes, Marielza Andrade; Schöwe, Natalia Mendes; Monteiro-Silva, Karla Cristina; Baraldi-Tornisielo, Ticiana; Souza, Suzzanna Ingryd Gonçalves; Balthazar, Janaina; Albuquerque, Marilia Silva; Caetano, Ariadiny Lima; Viel, Tania Araujo; Buck, Hudson Sousa

    2015-01-01

    The use of lithium is well established in bipolar disorders and the benefits are being demonstrated in neurodegenerative disorders. Recently, our group showed that treatment with microdose lithium stabilized the cognitive deficits observed in Alzheimer's disease (AD) patients. In order to verify the lithium microdose potential in preventing the disease development, the aim of this work was to verify the effects of chronic treatment with microdose lithium given before and after the appearance of symptoms in a mouse model of a disease similar to AD. Transgenic mice (Cg-Tg(PDGFB-APPSwInd)20Lms/2J) and their non-transgenic litter mate genetic controls were treated with lithium carbonate (0.25mg/Kg/day in drinking water) for 16 or 8 months starting at two and ten months of age, respectively [corrected]. Similar groups were treated with water. At the end of treatments, both lithium treated transgenic groups and non-transgenic mice showed no memory disruption, different from what was observed in the water treated transgenic group. Transgenic mice treated with lithium since two months of age showed decreased number of senile plaques, no neuronal loss in cortex and hippocampus and increased BDNF density in cortex, when compared to non-treated transgenic mice. It is suitable to conclude that these data support the use of microdose lithium in the prevention and treatment of Alzheimer's disease, once the neurohistopathological characteristics of the disease were modified and the memory of transgenic animals was maintained.

  6. Chronic Microdose Lithium Treatment Prevented Memory Loss and Neurohistopathological Changes in a Transgenic Mouse Model of Alzheimer's Disease

    PubMed Central

    Monteiro-Silva, Karla Cristina; Baraldi-Tornisielo, Ticiana; Souza, Suzzanna Ingryd Gonçalves; Balthazar, Janaina; Albuquerque, Marilia Silva; Caetano, Ariadiny Lima; Viel, Tania Araujo; Buck, Hudson Sousa

    2015-01-01

    The use of lithium is well established in bipolar disorders and the benefits are being demonstrated in neurodegenerative disorders. Recently, our group showed that treatment with microdose lithium stabilized the cognitive deficits observed in Alzheimer’s disease (AD) patients. In order to verify the lithium microdose potential in preventing the disease development, the aim of this work was to verify the effects of chronic treatment with microdose lithium given before and after the appearance of symptoms in a mouse model of a disease similar to AD. Transgenic mice (Cg-Tg(PDGFB-APPSwInd)20Lms/2J) and their non-transgenic litter mate genetic controls were treated with lithium carbonate (1.2 mg/Kg/day in drinking water) for 16 or 8 months starting at two and ten months of age, respectively. Similar groups were treated with water. At the end of treatments, both lithium treated transgenic groups and non-transgenic mice showed no memory disruption, different from what was observed in the water treated transgenic group. Transgenic mice treated with lithium since two months of age showed decreased number of senile plaques, no neuronal loss in cortex and hippocampus and increased BDNF density in cortex, when compared to non-treated transgenic mice. It is suitable to conclude that these data support the use of microdose lithium in the prevention and treatment of Alzheimer’s disease, once the neurohistopathological characteristics of the disease were modified and the memory of transgenic animals was maintained. PMID:26605788

  7. Intravenous transplantation of bone marrow-derived mononuclear cells prevents memory impairment in transgenic mouse models of Alzheimer's disease.

    PubMed

    Kanamaru, Takuya; Kamimura, Naomi; Yokota, Takashi; Nishimaki, Kiyomi; Iuchi, Katsuya; Lee, Hyunjin; Takami, Shinya; Akashiba, Hiroki; Shitaka, Yoshitsugu; Ueda, Masayuki; Katsura, Ken-Ichiro; Kimura, Kazumi; Ohta, Shigeo

    2015-04-24

    Stem cell transplantation therapy is currently in clinical trials for the treatment of ischemic stroke, and several beneficial aspects have been reported. Similarly, in Alzheimer's disease (AD), stem cell therapy is expected to provide an efficient therapeutic approach. Indeed, the intracerebral transplantation of stem cells reduced amyloid-β (Aβ) deposition and rescued memory deficits in AD model mice. Here, we show that intravenous transplantation of bone marrow-derived mononuclear cells (BMMCs) improves cognitive function in two different AD mouse models, DAL and APP mice, and prevents neurodegeneration. GFP-positive BMMCs were isolated from tibiae and femurs of 4-week-old mice and then transplanted intravenously into DAL and APP mice. Transplantation of BMMCs suppressed neuronal loss and restored memory impairment of DAL mice to almost the same level as in wild-type mice. Transplantation of BMMCs to APP mice reduced Aβ deposition in the brain. APP mice treated with BMMCs performed significantly better on behavioral tests than vehicle-injected mice. Moreover, the effects were observed even with transplantation after the onset of cognitive impairment in DAL mice. Together, our results indicate that intravenous transplantation of BMMCs has preventive effects against the cognitive decline in AD model mice and suggest a potential therapeutic effect of BMMC transplantation therapy.

  8. Memory-strengthening activity of Glycyrrhiza glabra in exteroceptive and interoceptive behavioral models.

    PubMed

    Parle, Milind; Dhingra, Dinesh; Kulkarni, S K

    2004-01-01

    In the traditional system of medicine, the roots and rhizomes of Glycyrrhiza glabra have been employed clinically for centuries for their anti-inflammatory, anti-ulcer, expectorant, antimicrobial, and anxiolytic activities. The present study was undertaken to investigate the effects of G. glabra, popularly known as liquorice (Mulathi), on learning and memory. The elevated plus-maze and passive avoidance paradigm were employed to evaluate learning and memory parameters. Three doses (75, 150, and 300 mg/kg p.o.) of aqueous extract of G. glabra were administered for 7 successive days in separate groups of mice. The dose of 150 mg/kg of the aqueous extract of liquorice significantly improved learning and memory of mice. Furthermore, this dose reversed the amnesia induced by diazepam (1 mg/kg i.p.), scopolamine (0.4 mg/kg i.p.), and ethanol (1 g/kg i.p.). Anti-inflammatory and antioxidant properties of liquorice may be contributing favorably to the memory enhancement effect. Since scopolamine-induced amnesia was reversed by liquorice, it is possible that the beneficial effect on learning and memory may be because of facilitation of cholinergic transmission in brain. However, further studies are necessitated to identify the exact mechanism of action. In the present investigation, G. glabra has shown promise as a memory enhancer in both exteroceptive and interoceptive behavioral models of memory.

  9. 2-Phenylethynyl-butyltellurium enhances learning and memory impaired by scopolamine in mice.

    PubMed

    Souza, Ana Cristina G; Bruning, César A; Acker, Carmine I; Neto, José S S; Nogueira, Cristina W

    2013-08-01

    Taking into account the memory-enhancing properties of 2-phenylethynyl-butyltellurium (PEBT) and the constant search for drugs that improve cognitive performance, the present study was designed to investigate the effect of PEBT on cognitive impairment induced by scopolamine in mice. PEBT (10 mg/kg, gavage) was administered to mice 1 h before the probe trial in the Morris water maze task. Memory impairment was induced by scopolamine (1 mg/kg, intraperitoneally) 30 min before the probe trial. PEBT significantly ameliorated the scopolamine-induced impairment of long-term memory, as indicated by a decrease in escape latency and an increase in the number of crossings of the platform location when compared with the amnesic mice. To evaluate the effect of PEBT on different phases of memory (acquisition, consolidation, and retrieval) impaired by scopolamine, the step-down inhibitory avoidance task was used. Scopolamine was administered 30 min before training (acquisition), test (retrieval), or immediately after training (consolidation). PEBT, administered 30 min before scopolamine, increased step-down latency in memory-impaired mice, improving the consolidation and retrieval stages, but not acquisition. No significant alterations in locomotor or exploratory behaviors were found in animals treated with PEBT and/or scopolamine. PEBT improved memory deficits during consolidation and retrieval induced by scopolamine.

  10. Prevention of meningococcal serogroup B infections in children: a protein-based vaccine induces immunologic memory.

    PubMed

    de Kleijn, E D; de Groot, R; Lafeber, A B; Labadie, J; van Limpt, C J; Visser, J; Berbers, G A; van Alphen, L; Rümke, H C

    2001-07-01

    Immunologic memory against meningococci was studied in 177 children (100 children were 10-11 years old and 77 were 5-6 years old) 2.5 years after vaccination with hexavalent meningococcal outer membrane vesicle (OMV) vaccine or hepatitis B (HepB) vaccine. Children were revaccinated with monovalent P1.7(h),4 meningococcal OMV vaccine. Serum bactericidal antibodies (SBAs) were measured before revaccination and after 4-6 weeks. A minimum 4-fold increase in SBAs against serosubtype P1.7(h),4 was detected in 48.5% of the children after hexavalent meningococcal vaccine and in 8.9% after HepB vaccine. Of the initial responders given hexavalent meningococcal vaccine, 78% had > or =4-fold increase in SBAs against strain P1.4. Thus, immunologic memory is present in toddlers and school-aged children previously given 3 hexavalent meningococcal vaccinations. Booster vaccination with monovalent P1.7(h),4 meningococcal OMV vaccine induces a significant increase in SBAs against serosubtype P1.7(h),4 and cross-reactivity against other serosubtypes in the hexavalent vaccine.

  11. Spirulina prevents memory dysfunction, reduces oxidative stress damage and augments antioxidant activity in senescence-accelerated mice.

    PubMed

    Hwang, Juen-Haur; Lee, I-Te; Jeng, Kee-Ching; Wang, Ming-Fu; Hou, Rolis Chien-Wei; Wu, Su-Mei; Chan, Yin-Ching

    2011-01-01

    Spirulina has proven to be effective in treating certain cancers, hyperlipidemia, immunodeficiency, and inflammatory processes. In this study, we aimed to investigate the effects of Spirulina on memory dysfunction, oxidative stress damage and antioxidant enzyme activity. Three-month-old male senescence-accelerated prone-8 (SAMP8) mice were randomly assigned to either a control group or to one of two experimental groups (one receiving daily dietary supplementation with 50 mg/kg BW and one with 200 mg/kg BW of Spirulina platensis water extract). Senescence-accelerated-resistant (SAMR1) mice were used as the external control. Results showed that the Spirulina-treated groups had better passive and avoidance scores than the control group. The amyloid β-protein (Aβ) deposition was significantly reduced at the hippocampus and whole brain in both Spirulina groups. The levels of lipid peroxidation were significantly reduced at the hippocampus, striatum, and cortex in both Spirulina groups, while catalase activity was significantly higher only in the 200 mg/kg BW Spirulina group than in the control group. Glutathione peroxidase activity was significantly higher only in the cortex of the 200 mg/kg group than in that of the SAMP8 control group. However, superoxide dismutase activity in all parts of the brain did not significantly differ among all groups. In conclusion, Spirulina platensis may prevent the loss of memory possibly by lessening Aβ protein accumulation, reducing oxidative damage and mainly augmenting the catalase activity.

  12. Control of an innovative super-capacitor-powered shape-memory-alloy actuated accumulator for blowout preventer

    NASA Astrophysics Data System (ADS)

    Chen, Jian; Li, Peng; Song, Gangbing; Ren, Zhang

    2017-01-01

    The design of a super-capacitor-powered shape-memory-alloy (SMA) actuated accumulator for blowout preventer (BOP) presented in this paper featured several advantages over conventional hydraulic accumulators including instant large current drive, quick system response and elimination of need for the pressure conduits. However, the mechanical design introduced two challenges, the nonlinear nature of SMA actuators and the varying voltage provided by a super capacitor, for control system design. A cerebellar model articulation controller (CMAC) feedforward plus PID controller was developed with the aim of compensation for these adverse effects. Experiments were conducted on a scaled down model and experimental results show that precision control can be achieved with the proposed configurations and algorithms.

  13. High intelligence prevents the negative impact of anxiety on working memory.

    PubMed

    Chuderski, Adam

    2015-01-01

    Using a large sample and the confirmatory factor analysis, the study investigated the relationships between anxiety, working memory (WM) and (fluid) intelligence. The study showed that the negative impact of anxiety on WM functioning diminishes with increasing intelligence, and that anxiety can significantly affect WM only in people below average intelligence. This effect could not be fully explained by the sheer differences in WM capacity (WMC), suggesting the importance of higher-level cognition in coping with anxiety. Although intelligence moderated the impact of anxiety on WM, it was only weakly related to anxiety. In contrast to previous studies, anxiety explained the substantial amount of WMC variance (17.8%) in less intelligent participants, but none of the variance in more intelligent ones. These results can be explained in terms of either increased motivation of intelligent but anxious people to cope with a WM task, or their ability to compensate decrements in WM.

  14. Maternal separation enhances object location memory and prevents exercise-induced MAPK/ERK signalling in adult Sprague-Dawley rats.

    PubMed

    Makena, Nokuthula; Bugarith, Kishor; Russell, Vivienne A

    2012-09-01

    Early life stress increases the risk of developing psychopathology accompanied by reduced cognitive function in later life. Maternal separation induces anxiety-like behaviours and is associated with impaired memory. On the other hand, exercise has been shown to diminish anxiety-like behaviours and improve cognitive function. The effects of maternal separation and exercise on anxiety, memory and hippocampal proteins were investigated in male Sprague-Dawley rats. Maternal separation produced anxiety-like behaviours which were reversed by exercise. Maternal separation also enhanced object location memory which was not affected by exercise. Exercise did, however, increase synaptophysin and phospho-extracellular signal-regulated kinase (p-ERK) in the hippocampus of non-separated rats and this effect was not observed in maternally separated rats. These findings show that maternal separation selectively enhanced n memory and prevented activation of the MAPK/ERK signalling pathway in the adult rat hippocampus.

  15. Maternal separation enhances object location memory and prevents exercise-induced MAPK/ERK signalling in adult Sprague–Dawley rats

    PubMed Central

    Bugarith, Kishor; Russell, Vivienne A

    2012-01-01

    Early life stress increases the risk of developing psychopathology accompanied by reduced cognitive function in later life. Maternal separation induces anxiety-like behaviours and is associated with impaired memory. On the other hand, exercise has been shown to diminish anxiety-like behaviours and improve cognitive function. The effects of maternal separation and exercise on anxiety, memory and hippocampal proteins were investigated in male Sprague–Dawley rats. Maternal separation produced anxiety-like behaviours which were reversed by exercise. Maternal separation also enhanced object location memory which was not affected by exercise. Exercise did, however, increase synaptophysin and phospho-extracellular signal-regulated kinase (p-ERK) in the hippocampus of non-separated rats and this effect was not observed in maternally separated rats. These findings show that maternal separation selectively enhanced n memory and prevented activation of the MAPK/ERK signalling pathway in the adult rat hippocampus. PMID:22476924

  16. 7,8-Dihydroxyflavone Prevents Synaptic Loss and Memory Deficits in a Mouse Model of Alzheimer's Disease

    PubMed Central

    Zhang, Zhentao; Liu, Xia; Schroeder, Jason P; Chan, Chi-Bun; Song, Mingke; Yu, Shan Ping; Weinshenker, David; Ye, Keqiang

    2014-01-01

    Synaptic loss in the brain correlates well with disease severity in Alzheimer disease (AD). Deficits in brain-derived neurotrophic factor/tropomyosin-receptor-kinase B (TrkB) signaling contribute to the synaptic dysfunction of AD. We have recently identified 7,8-dihydroxyflavone (7,8-DHF) as a potent TrkB agonist that displays therapeutic efficacy toward various neurological diseases. Here we tested the effect of 7,8-DHF on synaptic function in an AD model both in vitro and in vivo. 7,8-DHF protected primary neurons from Aβ-induced toxicity and promoted dendrite branching and synaptogenesis. Chronic oral administration of 7,8-DHF activated TrkB signaling and prevented Aβ deposition in transgenic mice that coexpress five familial Alzheimer's disease mutations (5XFAD mice). Moreover, 7,8-DHF inhibited the loss of hippocampal synapses, restored synapse number and synaptic plasticity, and prevented memory deficits. These results suggest that 7,8-DHF represents a novel oral bioactive therapeutic agent for treating AD. PMID:24022672

  17. Stachys sieboldii (Labiatae, Chorogi) Protects against Learning and Memory Dysfunction Associated with Ischemic Brain Injury.

    PubMed

    Harada, Shinichi; Tsujita, Tsukasa; Ono, Akiko; Miyagi, Kei; Mori, Takaharu; Tokuyama, Shogo

    2015-01-01

    Stachys sieboldii (Labiatae; Chinese artichoke, a tuber), "chorogi" in Japanese, has been extensively used in folk medicine, and has a number of pharmacological properties, including antioxidative activity. However, few studies have examined the neuroprotective effects of S. sieboldii tuber extract (chorogi extract), and it remains unknown whether the extract can alleviate learning and memory dysfunction associated with vascular dementia or Alzheimer's disease. Therefore, in this study, we investigated the neuroprotective effects of chorogi extract, and examined its protection against learning and memory dysfunction using Ginkgo biloba leaf extract (ginkgo extract) as a positive control. Mice were subjected to bilateral carotid artery occlusion (BCAO) for 30 min. Oral administration of chorogi extract or ginkgo extract significantly reduced post-ischemic glucose intolerance on day 1 and neuronal damage including memory impairment on day 3 after BCAO, compared with the vehicle-treated group. Neither herbal medicine affected locomotor activity. Furthermore, neither significantly alleviated scopolamine-induced learning and memory impairment. In primary neurons, neuronal survival rate was significantly reduced by hydrogen peroxide treatment. This hydrogen peroxide-induced neurotoxicity was significantly suppressed by chorogi extract and ginkgo extract. Taken together, our findings suggest that chorogi extract as well as ginkgo extract can protect against learning and memory dysfunction associated with ischemic brain injury through an antioxidative mechanism.

  18. GLP-1 analogue CJC-1131 prevents amyloid β protein-induced impirments of spatial memory and synaptic plasticity in rats.

    PubMed

    Zhang, Sheng-Xiao; Cai, Hong-Yan; Ma, Xiao-Wen; Yuan, Li; Zhang, Jun; Wang, Zhao-Jun; Li, Yu-Feng; Qi, Jin-Shun

    2017-03-15

    Although amyloid β protein (Aβ) has been recognized as one of the main pathological characteristics in the brain of Alzheimer's disease (AD), the effective strategies against Aβ neurotoxicity are still deficient up to now. Glucagon-like peptide 1 (GLP-1), a natural gut hormone, was found to be effective in modulating insulin signaling and neural protection, but short half-life limited its clinical application in AD treatment. CJC-1131, a newly designed GLP-1 analogue with very longer half-life, has shown good effectiveness in the treatment of type 2 diabetes mellitus (T2DM). However, it is unclear whether CJC-1131 could alleviate Aβ-induced neurotoxicity in cognitive behavior and electrophysiological property. The present study investigated the effects of CJC-1131 on the Aβ-induced impairments in spatial memory and synaptic plasticity of rats by using Morris water maze test and in vivo field potential recording. The results showed that Aβ1-42-induced increase in the escape latency of rats in hidden platform test and decrease in swimming time percent in target quadrant were effectively reversed by CJC-1131 pretreatment. Further, CJC-1131 prevented against Aβ1-42-induced suppression of hippocampal long term potentiation (LTP). In addition, Aβ1-42 injection resulted in a significant decrease of p-PKA in the hippocampus, which was effectively prevented by CJC-1131 treatment. These results indicated that CJC-1131 protected the cognitive function and synaptic plasticity of rats against Aβ-induced impairments, suggesting that GLP-1 analogue CJC-1131 might be potentially beneficial to the prevention and treatment of AD, especially those with T2DM or blood glucose abnormality.

  19. Transiently increasing cAMP levels selectively in hippocampal excitatory neurons during sleep deprivation prevents memory deficits caused by sleep loss.

    PubMed

    Havekes, Robbert; Bruinenberg, Vibeke M; Tudor, Jennifer C; Ferri, Sarah L; Baumann, Arnd; Meerlo, Peter; Abel, Ted

    2014-11-19

    The hippocampus is particularly sensitive to sleep loss. Although previous work has indicated that sleep deprivation impairs hippocampal cAMP signaling, it remains to be determined whether the cognitive deficits associated with sleep deprivation are caused by attenuated cAMP signaling in the hippocampus. Further, it is unclear which cell types are responsible for the memory impairments associated with sleep deprivation. Transgenic approaches lack the spatial resolution to manipulate specific signaling pathways selectively in the hippocampus, while pharmacological strategies are limited in terms of cell-type specificity. Therefore, we used a pharmacogenetic approach based on a virus-mediated expression of a Gαs-coupled Drosophila octopamine receptor selectively in mouse hippocampal excitatory neurons in vivo. With this approach, a systemic injection with the receptor ligand octopamine leads to increased cAMP levels in this specific set of hippocampal neurons. We assessed whether transiently increasing cAMP levels during sleep deprivation prevents memory consolidation deficits associated with sleep loss in an object-location task. Five hours of total sleep deprivation directly following training impaired the formation of object-location memories. Transiently increasing cAMP levels in hippocampal neurons during the course of sleep deprivation prevented these memory consolidation deficits. These findings demonstrate that attenuated cAMP signaling in hippocampal excitatory neurons is a critical component underlying the memory deficits in hippocampus-dependent learning tasks associated with sleep deprivation.

  20. Transiently Increasing cAMP Levels Selectively in Hippocampal Excitatory Neurons during Sleep Deprivation Prevents Memory Deficits Caused by Sleep Loss

    PubMed Central

    Bruinenberg, Vibeke M.; Tudor, Jennifer C.; Ferri, Sarah L.; Baumann, Arnd; Meerlo, Peter

    2014-01-01

    The hippocampus is particularly sensitive to sleep loss. Although previous work has indicated that sleep deprivation impairs hippocampal cAMP signaling, it remains to be determined whether the cognitive deficits associated with sleep deprivation are caused by attenuated cAMP signaling in the hippocampus. Further, it is unclear which cell types are responsible for the memory impairments associated with sleep deprivation. Transgenic approaches lack the spatial resolution to manipulate specific signaling pathways selectively in the hippocampus, while pharmacological strategies are limited in terms of cell-type specificity. Therefore, we used a pharmacogenetic approach based on a virus-mediated expression of a Gαs-coupled Drosophila octopamine receptor selectively in mouse hippocampal excitatory neurons in vivo. With this approach, a systemic injection with the receptor ligand octopamine leads to increased cAMP levels in this specific set of hippocampal neurons. We assessed whether transiently increasing cAMP levels during sleep deprivation prevents memory consolidation deficits associated with sleep loss in an object–location task. Five hours of total sleep deprivation directly following training impaired the formation of object–location memories. Transiently increasing cAMP levels in hippocampal neurons during the course of sleep deprivation prevented these memory consolidation deficits. These findings demonstrate that attenuated cAMP signaling in hippocampal excitatory neurons is a critical component underlying the memory deficits in hippocampus-dependent learning tasks associated with sleep deprivation. PMID:25411499

  1. Forced Treadmill Exercise Prevents Spatial Memory Deficits in Aged Rats Probably Through the Activation of Na(+), K(+)-ATPase in the Hippocampus.

    PubMed

    Vanzella, Cláudia; Sanches, Eduardo Farias; Odorcyk, Felipe Kawa; Nicola, Fabrício; Kolling, Janaína; Longoni, Aline; Dos Santos, Tiago Marcon; Wyse, Angela Terezinha de Souza; Netto, Carlos Alexandre

    2017-02-16

    Regular physical activity has shown to improve the quality of life and to prevent age-related memory deficits. Memory processing requires proper regulation of several enzymes such as sodium-potassium adenosine triphosphatase (Na(+), K(+)-ATPase) and acetylcholinesterase (AChE), which have a pivotal role in neuronal transmission. The present study investigated the effects of a treadmill running protocol in young (3 months), mature (6 months) and aged (22 months) Wistar rats, on: (a) cognitive function, as assessed in the Water maze spatial tasks; (b) Na(+), K(+)-ATPase and AChE activities in the hippocampus following cognitive training alone or treadmill running combined with cognitive training. Animals of all ages were assigned to naïve (with no behavioral or exercise training), sedentary (non-exercised, with cognitive training) and exercised (20 min of daily running sessions, 3 times per week for 4 weeks and with cognitive training) groups. Cognition was assessed by reference and working memory tasks run in the Morris Water maze; 24 h after last session of behavioral testing, hippocampi were collected for biochemical analysis. Results demonstrated that: (a) a moderate treadmill running exercise prevented spatial learning and memory deficits in aged rats; (b) training in the Water maze increased both Na(+), K(+)-ATPase and AChE activities in the hippocampus of mature and aged rats; (c) aged exercised rats displayed an even further increase of Na(+), K(+)-ATPase activity in the hippocampus, (d) enzyme activity correlated with memory performance in aged rats. It is suggested that exercise prevents spatial memory deficits in aged rats probably through the activation of Na(+), K(+)-ATPase in the hippocampus.

  2. Chronic Treatment with Naltrexone Prevents Memory Retention Deficits in Rats Poisoned with the Sarin Analog Diisopropylfluorophosphate (DFP) and Treated with Atropine and Pralidoxime.

    PubMed

    Brewer, Kori L; Tran, Tuan; Meggs, William J

    2015-12-01

    Humans and rats poisoned with sarin develop chronic neurological disabilities that are not prevented with standardized antidotal therapy. We hypothesized that rats poisoned with the sarin analogue diisopropylfluorophosphate (DFP) and resuscitated with atropine and pralidoxime would have long-term memory deficits that were preventable with naltrexone treatment. Long Evans rats (250-275 g) were randomized to: DFP (N = 8): single subcutaneous (SC) injection of DFP (5 mg/kg). Treatment (N = 9): DFP (5 mg/kg) followed by chronic naltrexone (5 mg/kg/day × 12 weeks). Control (N = 12): single SC injection of isopropyl alcohol, (DFP vehicle) followed by chronic naltrexone (5 mg/kg/day). If toxicity developed after injection, antidotal therapy was initiated with atropine (2 mg/kg) and pralidoxime (25 mg/kg) and repeated as needed. After 12 weeks, rats underwent testing for place learning (acquisition) across 5 days of training using the Morris Water Maze. On day 6 a memory retention test was performed. Statistical analysis was performed using IBM SPSS Statistics. Rats receiving DFP rapidly developed toxicity requiring antidotal rescue. No differences in acquisition were seen between the DFP vs. DFP + naltrexone rats. During memory testing, DFP-poisoned rats spent significantly less time (29.4 ± 2.11 versus 38.5 ± 2.5 s, p < 0.05) and traveled less distance (267 ± 24.6 versus 370 ± 27.5 cm, p < 0.05) in the target quadrant compared to the treatment group. Treatment rats performed as well as control rats (p > 0.05) on the test for memory retention. Poisoning with DFP induced impaired memory retention. Deficits were not prevented by acute rescue with atropine and pralidoxime. Chronic naltrexone treatment led to preserved memory after DFP poisoning.

  3. Nardostachys jatamansi improves learning and memory in mice.

    PubMed

    Joshi, Hanumanthachar; Parle, Milind

    2006-01-01

    Cure of cognitive disorders such as amnesia, attention deficit, and Alzheimer's disease is still far from being realized in the field of medicine. Nootropic agents such as piracetam, aniracetam, and choline esterase inhibitors like donepezil are being used for improving memory, mood, and behavior, but the resulting side effects associated with these agents have made their applicability limited. In Ayurveda, the roots of Nardostachys jatamansi have been clinically employed for their anti-ischemic, antioxidant, anticonvulsant, and neuroprotective activities. The present study was undertaken to assess the potential of N. jatmansi as a memory enhancer. The elevated plus maze and the passive avoidance paradigm were employed to evaluate learning and memory parameters. Three doses (50, 100, and 200 mg/kg, p.o.) of an ethanolic extract of N. jatamansi were administered for 8 successive days to both young and aged mice. The 200 mg/kg dose of N. jatmansi ethanolic extract significantly improved learning and memory in young mice and also reversed the amnesia induced by diazepam (1 mg/kg, i.p.) and scopolamine (0.4 mg/kg, i.p.). Furthermore, it also reversed aging-induced amnesia due to natural aging of mice. As scopolamine-induced amnesia was reversed, it is possible that the memory improvement may be because of facilitation of cholinergic transmission in the brain. Hence, N. jatmansi might prove to be a useful memory restorative agent in the treatment of dementia seen in elderly persons. The underlying mechanism of action can be attributed to its antioxidant property.

  4. Chronic nicotine restores normal Aβ levels and prevents short-term memory and E-LTP impairment in Aβ rat model of Alzheimer's disease.

    PubMed

    Srivareerat, Marisa; Tran, Trinh T; Salim, Samina; Aleisa, Abdulaziz M; Alkadhi, Karim A

    2011-05-01

    Alzheimer's disease (AD) is a devastating neurodegenerative disorder characterized by increased deposition of beta-amyloid (Aβ) peptides and progressive cholinergic dysfunction in regions of the brain involved in learning and memory processing. In AD, progressive accumulation of Aβ peptide impairs nicotinic acetylcholine receptor (nAChR) function by an unknown mechanism believed to involve α(7)- and α(4)β(2)-nAChR blockade. The three approaches of the current study evaluated the effects of chronic nicotine treatment in the prevention of Aβ-induced impairment of learning and short-term memory. Rat AD model was induced by 14-day i.c.v. osmotic pump infusion of a 1:1 mixture of 300 pmol/day Aβ(1-40)/Aβ(1-42) or Aβ(40-1) (inactive peptide, control). The effect of nicotine (2 mg/(kg day)) on Aβ-induced spatial learning and memory impairments was assessed by evaluation of performance in the radial arm water maze (RAWM), in vivo electrophysiological recordings of early-phase long-term potentiation (E-LTP) in urethane-anesthetized rats, and immunoblot analysis to determine changes in the levels of beta-site amyloid precursor protein (APP)-cleaving enzyme (BACE), Aβ and memory-related proteins. The results indicate that 6 weeks of nicotine treatment reduced the levels of Aβ(1-40) and BACE1 peptides in hippocampal area CA1 and prevented Aβ-induced impairment of learning and short-term memory. Chronic nicotine also prevented the Aβ-induced inhibition of basal synaptic transmission and LTP in hippocampal area CA1. Furthermore, chronic nicotine treatment prevented the Aβ-induced reduction of α(7)- and α(4)-nAChR. These effects of nicotine may be due, at least in part, to upregulation of brain derived neurotropic factor (BDNF).

  5. Prevention

    MedlinePlus

    ... our e-newsletter! Aging & Health A to Z Prevention Basic Facts & Information Some factors that affect your ... control of the things that you can change. Preventive Recommendations for Adults Aged 65 and Older The ...

  6. Prevention

    MedlinePlus

    ... Is Strong Error processing SSI file About Heart Disease & Stroke Prevention Heart disease and stroke are an epidemic in ... to avoid secondhand smoke. Barriers to Effective Heart Disease & Stroke Prevention Many people with key risk factors for heart ...

  7. Verbal Fluency and Early Memory Decline: Results from the Wisconsin Registry for Alzheimer's Prevention

    PubMed Central

    Mueller, Kimberly Diggle; Koscik, Rebecca L.; LaRue, Asenath; Clark, Lindsay R.; Hermann, Bruce; Johnson, Sterling C.; Sager, Mark A.

    2015-01-01

    This study examined the relationship between phonemic and semantic (category) verbal fluency and cognitive status in the Wisconsin Registry for Alzheimer’s Prevention (WRAP), a longitudinal cohort enriched for family history of Alzheimer’s disease. Participants were 283 WRAP subjects (age 53.1[6.5] years at baseline); who had completed three waves of assessment, over ∼6 years and met psychometric criteria either for “cognitively healthy” (CH) or for psychometric amnestic mild cognitive impairment (aMCI) using an approach that did not consider fluency scores. CH and aMCI groups differed significantly on phonemic total scores, category total scores, phonemic switching, and category mean cluster size. These results suggest that measures of both phonemic and semantic fluency yield lower scores in persons with evidence of psychometric aMCI compared with those who are CH. Differences have not previously been reported in a group this young, and provide evidence for the importance of including multiple verbal fluency tests targeting preclinical Alzheimer’s disease. PMID:26025231

  8. Prazosin, an α(1)-adrenoceptor antagonist, prevents memory deterioration in the APP23 transgenic mouse model of Alzheimer's disease.

    PubMed

    Katsouri, Loukia; Vizcaychipi, Marcela P; McArthur, Simon; Harrison, Ian; Suárez-Calvet, Marc; Lleo, Alberto; Lloyd, Dafydd G; Ma, Daqing; Sastre, Magdalena

    2013-04-01

    Noradrenergic deficits have been described in the hippocampus and the frontal cortex of Alzheimer's disease brains, which are secondary to locus coeruleus degeneration. Locus coeruleus is the brain stem nucleus responsible for synthesis of noradrenaline and from where all noradrenergic neurons project. In addition, it has been suggested that noradrenaline might play a role in modulating inflammatory responses in Alzheimer's disease. In this study we aimed to investigate the effect of various agonists and antagonists for adrenergic receptors on amyloid precursor protein processing. Among them, we found that prazosin, an α(1)-adrenoceptor antagonist, was able to reduce the generation of amyloid β in N2a cells. Treatment of transgenic APP23 mice with prazosin prevented memory deficits over time. Although prazosin did not influence amyloid plaque load, it induced astrocytic proliferation and increased the release of apolipoprotein E and anti-inflammatory cytokines. These findings suggest that chronic treatment with prazosin leads to an anti-inflammatory response with potential beneficial effects on cognitive performance.

  9. Cognitive-Enhancing Effect of Aronia melanocarpa Extract against Memory Impairment Induced by Scopolamine in Mice

    PubMed Central

    Lee, Hyeon Yong; Weon, Jin Bae; Jung, Youn Sik; Kim, Nam Young; Kim, Myong Ki; Ma, Choong Je

    2016-01-01

    Aronia melanocarpa (A. melanocarpa) berries are a fruit with a marked antioxidant effect. The objective of this study was to confirm the effect of A. melanocarpa berries extract against scopolamine-induced memory impairment in mice using the Morris water maze and passive avoidance test. Moreover, we determined a possible mechanism of the cognitive-enhancing effect involving AChE activity and BDNF and p-CREB expression in the hippocampus of mice. A. melanocarpa berries extract attenuated the learning and memory impairment induced by scopolamine in the Morris water maze (79.3 ± 0.8 s of 200 mg/kg and 64.4 ± 10.7 s of 400 mg/kg on day 4) and passive avoidance tests (46.0 ± 41.1 s of 200 mg/kg and 25.6 ± 18.7 s of 400 mg/kg). A. melanocarpa berries extract reduced the acetylcholinesterase level in the hippocampus of scopolamine-injected mice and increased BDNF and p-CREB expression in the hippocampus. The major compound, cyanidin-3-O-galactoside, also reversed memory impairment. These results showed that A. melanocarpa berries extract improved memory impairment by inhibiting AChE and increasing BDNF and p-CREB expression, and cyanidin-3-O-galactoside may be responsible for the effect of A. melanocarpa berries extract. PMID:27239211

  10. Lacosamide reduces HDAC levels in the brain and improves memory: Potential for treatment of Alzheimer's disease.

    PubMed

    Bang, Shraddha R; Ambavade, Shirishkumar D; Jagdale, Priti G; Adkar, Prafulla P; Waghmare, Arun B; Ambavade, Prashant D

    2015-07-01

    Lacosamide, a histone deacetylase (HDAC) inhibitor, has been approved for the treatment of epilepsy. Some HDAC inhibitors have been proven effective for the treatment of memory disorders. The present investigation was designed to evaluate the effect of lacosamide on memory and brain HDAC levels. The effect on memory was evaluated in animals with scopolamine-induced amnesia using the elevated plus maze, object recognition test, and radial arm maze. The levels of acetylcholinesterase and HDAC in the cerebral cortex were evaluated. Lacosamide at doses of 10 and 30mg/kg significantly reduced the transfer latency in the elevated plus maze. Lacosamide at a dose of 30mg/kg significantly increased the time spent with a familiar object in the object recognition test at the 24h interval and decreased the time spent in the baited arm. Moreover, at this dose, the number of errors in the radial arm maze at 3 and 24h intervals was minimized and a reduction in the level of HDAC1, but not acetylcholinesterase, was observed in the cerebral cortex. These effects of lacosamide are equivalent to those of piracetam at a dose of 300mg/kg. These results suggest that lacosamide at a 30mg/kg dose improves disrupted memory, possibly by inhibiting HDAC, and could be used to treat amnesic symptoms of Alzheimer's disease.

  11. Enriched environment prevents hypobaric hypoxia induced memory impairment and neurodegeneration: role of BDNF/PI3K/GSK3β pathway coupled with CREB activation.

    PubMed

    Jain, Vishal; Baitharu, Iswar; Prasad, Dipti; Ilavazhagan, Govindasamy

    2013-01-01

    Adverse environmental conditions such as hypobaric hypoxia (HH) cause memory impairment by affecting cellular machinery leading to neurodegeneration. Providing enriched environment (EE) is found to be beneficial for curing several neurodegenerative disorders. The protective role of EE in preventing HH induced neuronal death has been reported previously but the involved mechanism is still not clearly understood. The present study is an attempt to verify the impact of EE on spatial memory during HH and also to explore the possible role of neurotrophin in EE mediated neuroprotection. Signaling mechanism involved in neuroprotection was also explored. Male Sprague Dawley rats were simulated to HH condition in an Animal Decompression Chamber at an altitude of 25000 feet in standard and enriched cages for 7 days. Spatial memory was assessed through Morris Water Maze. Role of different neurotrophins was explored by gene silencing and inhibitors for their respective receptors. Further, using different blockers signaling pathway was also explored. Finding of the present study suggested that EE prevents HH mediated memory impairment and neurodegeneration. Also brain-derived neurotrophic factor (BDNF) plays a major role in EE mediated neuroprotection and it effectively prevented neurodegeneration by activating PI3K/AKT pathway resulting in GSK3β inactivation which further inhibits apoptosis. Moreover GSK3β phosphorylation and hence its inactivation upregulates CREB phosphorylation which may also accounts for activation of survival machinery in cells and provides neuroprotection. From these observations it can be postulated that EE has a therapeutic potential in amelioration of HH induced memory impairment and neurodegeneration. Hence it may be used as a non invasive and non pharmacological intervention against various neurological disorders.

  12. Caffeine consumption prevents memory impairment, neuronal damage, and adenosine A2A receptors upregulation in the hippocampus of a rat model of sporadic dementia.

    PubMed

    Espinosa, Janaína; Rocha, Andreia; Nunes, Fernanda; Costa, Marcelo S; Schein, Vanessa; Kazlauckas, Vanessa; Kalinine, Eduardo; Souza, Diogo O; Cunha, Rodrigo A; Porciúncula, Lisiane O

    2013-01-01

    Intracerebroventricular (icv) streptozotocin (STZ) administration induces pathological and behavioral alterations similar to those observed in Alzheimer's disease (AD) and is thus considered an experimental model of sporadic AD. Since caffeine (an adenosine receptor antagonist) and selective antagonists of adenosine A2A receptors modify the course of memory impairment in different amyloid-β-based experimental models of AD, we now tested the impact of caffeine on STZ-induced dementia and associated neurodegeneration in the hippocampus as well as on the expression and density of adenosine receptors. Adult male rats received a bilateral infusion of saline or STZ (3 mg/kg, icv), which triggered memory deficits after four weeks, as gauged by impaired object recognition memory. This was accompanied by a reduced NeuN immunoreactivity in the hippocampal CA1 region and an increased expression and density of adenosine A2A receptors (A2AR), but not A1R, in the hippocampus. Caffeine consumption (1 g/L in the drinking water starting 2 weeks before the STZ challenge) prevented the STZ-induced memory impairment and neurodegeneration as well as the upregulation of A2AR. These findings provide the first demonstration that caffeine prevents sporadic dementia and implicate the control of central A2AR as its likely mechanism of action.

  13. Saffron (Crocus sativus L.) extract prevents and improves D-galactose and NaNO2 induced memory impairment in mice

    PubMed Central

    Dashti-r, M.H.; Zeinali, F.; Anvari, M.; Hosseini, S.M.

    2012-01-01

    This study was conducted to examine the effects of saffron extract on preventing D-galactose and NaNO2 induced memory impairment and improving learning and memory deficits in amnestic mice. In this study, the learning and memory functions in ovariectomized mice were examined by the one way passive and active avoidance tests. In active avoidance test, training in amnestic treated (AT) and amnestic prophylaxis (AP) groups, was improved so that there was a significant difference between them and the amnestic control (AC) group. In passive avoidance test, animal's step through latency, as an index for learning, in all test groups was significantly greater than control group. Total time spent in dark room (DS), which opposes the memory retention ability, in AC was significantly greater than AT group at 1 and 2 hours after full training, while there was not any significant difference between this index in AP and AT as compared with normal control (NC) group. Our findings indicate that saffron hydro-alcoholic extract prevents and improves amnesia induced by D-galactose and NaNO2 in mice. PMID:27418908

  14. Acute treatment with bis selenide, an organic compound containing the trace element selenium, prevents memory deficits induced by reserpine in rats.

    PubMed

    Bortolatto, Cristiani Folharini; Guerra Souza, Ana Cristina; Wilhelm, Ethel Antunes; Nogueira, Cristina Wayne

    2013-01-01

    Taking into account the promising pharmacological actions of (Z)-2,3-bis(4-chlorophenylselanyl) prop-2-en-1-ol) (bis selenide), an organic compound containing the trace element selenium, and the constant search for drugs that improve the cognitive performance, the objective of the present study was to investigate whether bis selenide treatment ameliorates memory deficits induced by reserpine in rats. For this aim, male adult rats received a single subcutaneous injection of reserpine (1 mg/kg), a biogenic amine-depleting agent used to induce memory deficit. After 24 h, bis selenide at doses of 25 and 50 mg/kg was administered to rats by intragastric route, and 1 h later, the animals were submitted to behavior tasks. The effects of acute administration of bis selenide on memory were evaluated by social recognition, step-down passive avoidance, and object recognition paradigms. Exploratory and locomotor activities of rats were determined using the open-field test. Analysis of data revealed that the social memory disruption caused by reserpine was reversed by bis selenide at both doses. In addition, bis selenide, at the highest dose, prevented the memory deficit resulting from reserpine administration to rats in step-down passive avoidance and object recognition tasks. No significant alterations in locomotor and exploratory behaviors were found in animals treated with reserpine and/or bis selenide. Results obtained from distinct memory behavioral paradigms revealed that an acute treatment with bis selenide attenuated memory deficits induced by reserpine in rats.

  15. Administration of the TrkB receptor agonist 7,8-dihydroxyflavone prevents traumatic stress-induced spatial memory deficits and changes in synaptic plasticity.

    PubMed

    Sanz-García, Ancor; Knafo, Shira; Pereda-Pérez, Inmaculada; Esteban, José A; Venero, César; Armario, Antonio

    2016-09-01

    Post-traumatic stress disorder (PTSD) occurs after exposure to traumatic situations and it is characterized by cognitive deficits that include impaired explicit memory. The neurobiological bases of such PTSD-associated memory alterations are yet to be elucidated and no satisfactory treatment for them exists. To address this issue, we first studied whether a single exposure of young adult rats (60 days) to immobilization on boards (IMO), a putative model of PTSD, produces long-term behavioral effects (2-8 days) similar to those found in PTSD patients. Subsequently, we investigated whether the administration of the TrkB agonist 7,8-dihydroxyflavone (DHF) 8 h after stress (therapeutic window) ameliorated the PTSD-like effect of IMO and the associated changes in synaptic plasticity. A single IMO exposure induced a spatial memory impairment similar to that found in other animal models of PTSD or in PTSD patients. IMO also increased spine density and long-term potentiation (LTP) in the CA3-CA1 pathway. Significantly, DHF reverted both spatial memory impairment and the increase in LTP, while it produced no effect in the controls. These data provide novel insights into the possible neurobiological substrate for explicit memory impairment in PTSD patients, supporting the idea that the activation of the BDNF/TrkB pathway fulfils a protective role after severe stress. Administration of DHF in the aftermath of a traumatic experience might be relevant to prevent its long-term consequences. © 2016 Wiley Periodicals, Inc.

  16. Preventive effects of Salvia officinalis L. against learning and memory deficit induced by diabetes in rats: Possible hypoglycaemic and antioxidant mechanisms.

    PubMed

    Hasanein, Parisa; Felehgari, Zhila; Emamjomeh, Abbasali

    2016-05-27

    Learning and memory impairment occurs in diabetes. Salvia officinalis L. (SO) has been used in Iranian traditional medicine as a remedy against diabetes. We hypothesized that chronic administration of SO (400, 600 and 800mg/kg, p.o.) and its principal constituent, rosmarinic acid, would affect on passive avoidance learning (PAL) and memory in streptozocin-induced diabetic and non-diabetic rats. We also explored hypoglycemic and antioxidant activities of SO as the possible mechanisms. Treatments were begun at the onset of hyperglycemia. PAL was assessed 30days later. Retention test was done 24h after training. At the end, animals were weighed and blood samples were drawn for further analyzing of glucose and oxidant/antioxidant markers. Diabetes induced deficits in acquisition and retrieval processes. SO (600 and 800mg/kg) and rosmarinic acid reversed learning and memory deficits induced by diabetes and improved cognition of healthy rats. While the dose of 400mg/kg had no effect, the higher doses and rosmarinic acid inhibited hyperglycemia and lipid peroxidation as well as enhanced the activity of antioxidant enzymes superoxide dismutase and catalase. SO prevented diabetes-induced acquisition and memory deficits through inhibiting hyperglycemia, lipid peroxidation as well as enhancing antioxidant defense systems. Therefore, SO and its principal constituent rosmarinic acid represent a potential therapeutic option against diabetic memory impairment which deserves consideration and further examination.

  17. Spermidine Suppresses Age-Associated Memory Impairment by Preventing Adverse Increase of Presynaptic Active Zone Size and Release

    PubMed Central

    Gupta, Varun K.; Pech, Ulrike; Fulterer, Andreas; Ender, Anatoli; Mauermann, Stephan F.; Andlauer, Till F. M.; Beuschel, Christine; Thriene, Kerstin; Quentin, Christine; Schwärzel, Martin; Mielke, Thorsten; Madeo, Frank; Dengjel, Joern; Fiala, André; Sigrist, Stephan J.

    2016-01-01

    Memories are assumed to be formed by sets of synapses changing their structural or functional performance. The efficacy of forming new memories declines with advancing age, but the synaptic changes underlying age-induced memory impairment remain poorly understood. Recently, we found spermidine feeding to specifically suppress age-dependent impairments in forming olfactory memories, providing a mean to search for synaptic changes involved in age-dependent memory impairment. Here, we show that a specific synaptic compartment, the presynaptic active zone (AZ), increases the size of its ultrastructural elaboration and releases significantly more synaptic vesicles with advancing age. These age-induced AZ changes, however, were fully suppressed by spermidine feeding. A genetically enforced enlargement of AZ scaffolds (four gene-copies of BRP) impaired memory formation in young animals. Thus, in the Drosophila nervous system, aging AZs seem to steer towards the upper limit of their operational range, limiting synaptic plasticity and contributing to impairment of memory formation. Spermidine feeding suppresses age-dependent memory impairment by counteracting these age-dependent changes directly at the synapse. PMID:27684064

  18. Propranolol and the prevention of post-traumatic stress disorder: is it wrong to erase the "sting" of bad memories?

    PubMed

    Henry, Michael; Fishman, Jennifer R; Youngner, Stuart J

    2007-09-01

    The National Institute of Mental Health (Bethesda, MD) reports that approximately 5.2 million Americans experience post-traumatic stress disorder (PTSD) each year. PTSD can be severely debilitating and diminish quality of life for patients and those who care for them. Studies have indicated that propranolol, a beta-blocker, reduces consolidation of emotional memory. When administered immediately after a psychic trauma, it is efficacious as a prophylactic for PTSD. Use of such memory-altering drugs raises important ethical concerns, including some futuristic dystopias put forth by the President's Council on Bioethics. We think that adequate informed consent should facilitate ethical research using propranolol and, if it proves efficacious, routine treatment. Clinical evidence from studies should certainly continue to evaluate realistic concerns about possible ill effects of diminishing memory. If memory-attenuating drugs prove effective, we believe that the most immediate social concern is the over-medicalization of bad memories, and its subsequent exploitation by the pharmaceutical industry.

  19. Chronic and acute adenosine A2A receptor blockade prevents long-term episodic memory disruption caused by acute cannabinoid CB1 receptor activation.

    PubMed

    Mouro, Francisco M; Batalha, Vânia L; Ferreira, Diana G; Coelho, Joana E; Baqi, Younis; Müller, Christa E; Lopes, Luísa V; Ribeiro, Joaquim A; Sebastião, Ana M

    2017-05-01

    Cannabinoid-mediated memory impairment is a concern in cannabinoid-based therapies. Caffeine exacerbates cannabinoid CB1 receptor (CB1R)-induced memory deficits through an adenosine A1 receptor-mediated mechanism. We now evaluated how chronic or acute blockade of adenosine A2A receptors (A2ARs) affects long-term episodic memory deficits induced by a single injection of a selective CB1R agonist. Long-term episodic memory was assessed by the novel object recognition (NOR) test. Mice received an intraperitoneal (i.p.) injection of the CB1/CB2 receptor agonist WIN 55,212-2 (1 mg/kg) immediately after the NOR training, being tested for novelty recognition 24 h later. Anxiety levels were assessed by the Elevated Plus Maze test, immediately after the NOR. Mice were also tested for exploratory behaviour at the Open Field. For chronic A2AR blockade, KW-6002 (istradefylline) (3 mg/kg/day) was administered orally for 30 days; acute blockade of A2ARs was assessed by i.p. injection of SCH 58261 (1 mg/kg) administered either together with WIN 55,212-2 or only 30 min before the NOR test phase. The involvement of CB1Rs was assessed by using the CB1R antagonist, AM251 (3 mg/kg, i.p.). WIN 55,212-2 caused a disruption in NOR, an action absent in mice also receiving AM251, KW-6002 or SCH 58261 during the encoding/consolidation phase; SCH 58251 was ineffective if present during retrieval only. No effects were detected in the Elevated Plus maze or Open Field Test. The finding that CB1R-mediated memory disruption is prevented by antagonism of adenosine A2ARs, highlights a possibility to prevent cognitive side effects when therapeutic application of CB1R drugs is desired.

  20. Prevention

    MedlinePlus

    ... Ban For Clinicians Clinical Recognition Specimen Collection Treatment Smallpox Vaccine Guidance Infection Control: Hospital Infection Control: Home ... Mouth Infection) Poxvirus and Rabies Branch Travelers’ Health: Smallpox & Other Orthopoxvirus-Associated Infections Poxvirus Prevention Recommend on ...

  1. Intact learning and memory in rats following treatment with the dual orexin receptor antagonist almorexant

    PubMed Central

    Jenck, François

    2010-01-01

    Rationale Orexins play a key role in the maintenance of alertness and are implicated in the modulation of diverse physiological processes, including cognitive function. Almorexant, a dual orexin receptor antagonist, transiently and reversibly blocks the action of orexin peptides at both OX1 and OX2 receptors and increases time spent in rapid eye movement (REM) and non-REM sleep. Objectives We explored the direct effects on learning and memory of single and repeated administration of almorexant in rats. Methods Following administration of high doses of almorexant (300 mg/kg, p.o.), scopolamine (0.8 mg/kg, i.p.), combination almorexant-scopolamine, or vehicle alone, rats were trained on a Morris water maze spatial navigation task, or on a passive avoidance task. Results Rats treated with almorexant learned the spatial navigation task with similar efficacy as vehicle-treated animals. After 4 days, almorexant—but not vehicle-treated rats had established spatial memory; after 8 days, spatial memory had been established in both vehicle—and almorexant-treated rats. Scopolamine-treated rats failed to learn the spatial task. Both vehicle—and almorexant—but not scopolamine-treated rats demonstrated passive avoidance learning. Almorexant did not ameliorate scopolamine-induced impairment of learning in either task. Conclusions Rats treated with almorexant are fully capable of spatial and avoidance learning. PMID:20631993

  2. Scopolamine disrupts hippocampal activity during allocentric spatial memory in humans: an fMRI study using a virtual reality analogue of the Morris Water Maze.

    PubMed

    Antonova, Elena; Parslow, David; Brammer, Michael; Simmons, Andrew; Williams, Steven; Dawson, Gerard R; Morris, Robin

    2011-09-01

    The role of the septohippocampal cholinergic system in memory disorders is well established. The effects of cholinergic challenge in animals have been extensively studied using the Morris Water Maze (MWM) which engages allocentric spatial memory. The present study investigated the effect of the centrally active muscarinic antagonist scopolamine on allocentric spatial memory in humans using a virtual reality analogue of the MWM task, the Arena task. Twenty right-handed healthy male adults with a mean age of 28 years (range 23-35 years) were studied using functional MRI in a randomized double-blind cross-over design with scopolamine bromide (0.4 mg i.m.) or placebo (saline) administered 70-90 min before the beginning of the functional scan. Scopolamine induced a significant reduction in the activation of the hippocampus/parahippocampal gyrus compared with placebo. Furthermore, there was dissociation between hippocampus-based and striatal-based memory systems, which were significantly more activated in the placebo and scopolamine conditions, respectively. The activation of the striatal system under scopolamine challenge was accompanied by the activation of the amygdala. In conclusion, the study extends the well-documented finding in animals of the attenuating effect of scopolamine on hippocampal activity during allocentric spatial memory to humans. Furthermore, the results call for further investigation of the dissociation between the hippocampal and neostriatal memory systems during allocentric spatial processing under cholinergic blockade in humans.

  3. Efficacy of Memoral Herbal on Prevention of Electroconvulsive Therapy-Induced Memory Impairment in Mood Disorder Patients (Isfahan – Iran 2011)

    PubMed Central

    Mousavi, Seyed Ghafur; Mohsen, Ghasemi; Reza, Maracy M; Amrollah, Ebrahimi; Majid, Barekatain; Fariba, Noori

    2012-01-01

    Background: Electroconvulsive therapy (ECT) is one of the most efficacious treatment for major depressive disorder (MDD), it is also used as a rapid and efficacious treatment for other psychiatric disorders, especially treatment resistant ones. The cognitive impairment is one of the most important side effects of ECT. This study examined the Memoral herbal efficacy in prevention of ECT-induced memory impairment. Methods: In a randomized clinical trial, 70 patients with mood disorders who were candidates for ECT enrolled in either Memoral or Control group, and received either Memoral or placebo. The memory was assessed by Addenbrook Cognitive Examination (ACE), and the findings were analyzed by ANOVA under SPSS18. Results: The Memoral group patients showed significantly higher total ACE scores than placebo group (P < 0.001). The scores of attention and orientation, verbal fluency and memory subscales not only never decreased during the study in Memoral group, but also increased. There was no significant difference between these scores of Memoral and placebo groups for the subscales of language and visuospacial ability. Conclusion: The Memoral herbal is an efficacious and safe choice in prevention of ECT- induced cognitive impairment. PMID:22891152

  4. Acute low dose of MK-801 prevents memory deficits without altering hippocampal DARPP-32 expression and BDNF levels in sepsis survivor rats.

    PubMed

    Cassol-Jr, Omar J; Comim, Clarissa M; Constantino, Larissa S; Rosa, Daniela V F; Mango, Luiz Alexandre V; Stertz, Laura; Kapczinski, Flávio; Romano-Silva, Marco A; Quevedo, João; Dal-Pizzol, Felipe

    2011-01-01

    Sepsis is characterized by an intense inflammatory reaction with potential neurotoxic effects in the central nervous system and damage to memory and learning ability. We assessed the effects of acute low dose of MK-801 on the memory impairment, hippocampal BDNF levels and DARPP-32 expression ten days after sepsis. Under anesthesia, male Wistar rats underwent either cecal ligation and perforation (CLP) or sham. Then, the animals received either a single systemic injection of MK-801 (0.025 mg/kg) or saline solution. Ten days after CLP, the animals were submitted to the step-down inhibitory avoidance and object recognition tests. Also, the hippocampal BDNF protein levels and DARPP-32 expression were evaluated. MK-801 prevented cognitive impairment, but did not affect the hippocampal BDNF levels. DARPP-32 expression was significantly different only in the animals submitted to sepsis that received MK-801 treatment. Thus, we demonstrated that a single low dose of MK-801 prevented memory impairment without altering hippocampal DARPP-32 expression and BDNF levels.

  5. Single fluoxetine treatment before but not after stress prevents stress-induced hippocampal long-term depression and spatial memory retrieval impairment in rats.

    PubMed

    Han, Huili; Dai, Chunfang; Dong, Zhifang

    2015-07-28

    A growing body of evidence has shown that chronic treatment with fluoxetine, a widely prescribed medication for treatment of depression, can affect synaptic plasticity in the adult central nervous system. However, it is not well understood whether acute fluoxetine influences synaptic plasticity, especially on hippocampal CA1 long-term depression (LTD), and if so, whether it subsequently impacts hippocampal-dependent spatial memory. Here, we reported that LTD facilitated by elevated-platform stress in hippocampal slices was completely prevented by fluoxetine administration (10 mg/kg, i.p.) 30 min before stress. The LTD was not, however, significantly inhibited by fluoxetine administration immediately after stress. Similarly, fluoxetine incubation (10 μM) during electrophysiological recordings also displayed no influence on the stress-facilitated LTD. In addition, behavioral results showed that a single fluoxetine treatment 30 min before but not after acute stress fully reversed the impairment of spatial memory retrieval in the Morris water maze paradigm. Taken together, these results suggest that acute fluoxetine treatment only before, but not after stress, can prevent hippocampal CA1 LTD and spatial memory retrieval impairment caused by behavioral stress in adult animals.

  6. Preventing academic difficulties in preterm children: a randomised controlled trial of an adaptive working memory training intervention – IMPRINT study

    PubMed Central

    2013-01-01

    Background Very preterm children exhibit difficulties in working memory, a key cognitive ability vital to learning information and the development of academic skills. Previous research suggests that an adaptive working memory training intervention (Cogmed) may improve working memory and other cognitive and behavioural domains, although further randomised controlled trials employing long-term outcomes are needed, and with populations at risk for working memory deficits, such as children born preterm. In a cohort of extremely preterm (<28 weeks’ gestation)/extremely low birthweight (<1000 g) 7-year-olds, we will assess the effectiveness of Cogmed in improving academic functioning 2 years’ post-intervention. Secondary objectives are to assess the effectiveness of Cogmed in improving working memory and attention 2 weeks’, 12 months’ and 24 months’ post-intervention, and to investigate training related neuroplasticity in working memory neural networks 2 weeks’ post-intervention. Methods/Design This double-blind, placebo-controlled, randomised controlled trial aims to recruit 126 extremely preterm/extremely low birthweight 7-year-old children. Children attending mainstream school without major intellectual, sensory or physical impairments will be eligible. Participating children will undergo an extensive baseline cognitive assessment before being randomised to either an adaptive or placebo (non-adaptive) version of Cogmed. Cogmed is a computerised working memory training program consisting of 25 sessions completed over a 5 to 7 week period. Each training session takes approximately 35 minutes and will be completed in the child’s home. Structural, diffusion and functional Magnetic Resonance Imaging, which is optional for participants, will be completed prior to and 2 weeks following the training period. Follow-up assessments focusing on academic skills (primary outcome), working memory and attention (secondary outcomes) will be conducted at 2 weeks’, 12

  7. Resveratrol prevents age-related memory and mood dysfunction with increased hippocampal neurogenesis and microvasculature, and reduced glial activation.

    PubMed

    Kodali, Maheedhar; Parihar, Vipan K; Hattiangady, Bharathi; Mishra, Vikas; Shuai, Bing; Shetty, Ashok K

    2015-01-28

    Greatly waned neurogenesis, diminished microvasculature, astrocyte hypertrophy and activated microglia are among the most conspicuous structural changes in the aged hippocampus. Because these alterations can contribute to age-related memory and mood impairments, strategies efficacious for mitigating these changes may preserve cognitive and mood function in old age. Resveratrol, a phytoalexin found in the skin of red grapes having angiogenic and antiinflammatory properties, appears ideal for easing these age-related changes. Hence, we examined the efficacy of resveratrol for counteracting age-related memory and mood impairments and the associated detrimental changes in the hippocampus. Two groups of male F344 rats in late middle-age having similar learning and memory abilities were chosen and treated with resveratrol or vehicle for four weeks. Analyses at ~25 months of age uncovered improved learning, memory and mood function in resveratrol-treated animals but impairments in vehicle-treated animals. Resveratrol-treated animals also displayed increased net neurogenesis and microvasculature, and diminished astrocyte hypertrophy and microglial activation in the hippocampus. These results provide novel evidence that resveratrol treatment in late middle age is efficacious for improving memory and mood function in old age. Modulation of the hippocampus plasticity and suppression of chronic low-level inflammation appear to underlie the functional benefits mediated by resveratrol.

  8. Chronic caffeine prevents changes in inhibitory avoidance memory and hippocampal BDNF immunocontent in middle-aged rats.

    PubMed

    Sallaberry, Cássia; Nunes, Fernanda; Costa, Marcelo S; Fioreze, Gabriela T; Ardais, Ana Paula; Botton, Paulo Henrique S; Klaudat, Bruno; Forte, Thomás; Souza, Diogo O; Elisabetsky, Elaine; Porciúncula, Lisiane O

    2013-01-01

    Beneficial effects of caffeine on memory processes have been observed in animal models relevant to neurodegenerative diseases and aging, although the underlying mechanisms remain unknown. Because brain-derived neurotrophic factor (BDNF) is associated with memory formation and BDNF's actions are modulated by adenosine receptors, the molecular targets for the psychostimulant actions of caffeine, we here compare the effects of chronic caffeine (1 mg/mL drinking solution for 30 days) on short- and long term memory and on levels of hippocampal proBDNF, mature BDNF, TrkB and CREB in young (3 month old) and middle-aged (12 month old) rats. Caffeine treatment substantially reduced i) age-related impairments in the two types of memory in an inhibitory avoidance paradigm, and ii) parallel increases in hippocampal BDNF levels. In addition, chronic caffeine increased proBDNF and CREB concentrations, and decreased TrkB levels, in hippocampus regardless of age. These data provide new evidence in favor of the hypothesis that modifications in BDNF and related proteins in the hippocampus contribute to the pro-cognitive effects of caffeine on age-associated losses in memory encoding. This article is part of a Special Issue entitled 'Cognitive Enhancers'.

  9. Exercise is more effective than diet control in preventing high fat diet-induced β-amyloid deposition and memory deficit in amyloid precursor protein transgenic mice.

    PubMed

    Maesako, Masato; Uemura, Kengo; Kubota, Masakazu; Kuzuya, Akira; Sasaki, Kazuki; Hayashida, Naoko; Asada-Utsugi, Megumi; Watanabe, Kiwamu; Uemura, Maiko; Kihara, Takeshi; Takahashi, Ryosuke; Shimohama, Shun; Kinoshita, Ayae

    2012-06-29

    Accumulating evidence suggests that some dietary patterns, specifically high fat diet (HFD), increase the risk of developing sporadic Alzheimer disease (AD). Thus, interventions targeting HFD-induced metabolic dysfunctions may be effective in preventing the development of AD. We previously demonstrated that amyloid precursor protein (APP)-overexpressing transgenic mice fed HFD showed worsening of cognitive function when compared with control APP mice on normal diet. Moreover, we reported that voluntary exercise ameliorates HFD-induced memory impairment and β-amyloid (Aβ) deposition. In the present study, we conducted diet control to ameliorate the metabolic abnormality caused by HFD on APP transgenic mice and compared the effect of diet control on cognitive function with that of voluntary exercise as well as that of combined (diet control plus exercise) treatment. Surprisingly, we found that exercise was more effective than diet control, although both exercise and diet control ameliorated HFD-induced memory deficit and Aβ deposition. The production of Aβ was not different between the exercise- and the diet control-treated mice. On the other hand, exercise specifically strengthened the activity of neprilysin, the Aβ-degrading enzyme, the level of which was significantly correlated with that of deposited Aβ in our mice. Notably, the effect of the combination treatment (exercise and diet control) on memory and amyloid pathology was not significantly different from that of exercise alone. These studies provide solid evidence that exercise is a useful intervention to rescue HFD-induced aggravation of cognitive decline in transgenic model mice of AD.

  10. Negative modulation of α5 GABAA receptors in rats may partially prevent memory impairment induced by MK-801, but not amphetamine- or MK-801-elicited hyperlocomotion

    PubMed Central

    Stamenić, Tamara Timić; Joksimović, Srdjan; Biawat, Poonam; Stanković, Tamara; Marković, Bojan; Cook, James M; Savić, Miroslav M

    2016-01-01

    Reportedly, negative modulation of α5 GABAA receptors may improve cognition in normal and pharmacologically-impaired animals, and such modulation has been proposed as an avenue for treatment of cognitive symptoms in schizophrenia. This study assessed the actions of PWZ-029, administered at doses (2, 5 and 10 mg/kg) at which it reached micromolar concentrations in brain tissue with estimated free concentrations adequate for selective modulation of α5 GABAA receptors, in three cognitive tasks in male Wistar rats acutely treated with the noncompetitive N-methyl-D-aspartate – receptor antagonist, MK-801 (0.1 mg/kg), as well in tests of locomotor activity potentiated by MK-801 (0.2 mg/kg) or amphetamine (0.5 mg/kg). In a hormetic-like manner, only 5 mg/kg PWZ-029 reversed MK-801-induced deficits in novel object recognition test (visual recognition memory), whereas in the Morris water maze, the 2 mg/kg dose of PWZ-029 exerted partial beneficial effects on spatial learning impairment. PWZ-029 did not affect recognition memory deficits in social novelty discrimination procedure. Motor hyperactivity induced with MK-801 or amphetamine was not preventable by PWZ-029. Our results show that certain MK-801-induced memory deficits can be ameliorated by negative modulation of α5 GABAA receptors, and point to the need for further elucidation of their translational relevance to cognitive deterioration in schizophrenia. PMID:26105958

  11. Cocaine causes memory and learning impairments in rats: involvement of nuclear factor kappa B and oxidative stress, and prevention by topiramate.

    PubMed

    Muriach, María; López-Pedrajas, Rosa; Barcia, Jorge M; Sanchez-Villarejo, María V; Almansa, Inmaculada; Romero, Francisco J

    2010-08-01

    Different mechanisms have been suggested for cocaine toxicity including an increase in oxidative stress but the association between oxidative status in the brain and cocaine induced-behaviour is poorly understood. Nuclear factor kappa B (NFkappaB) is a sensor of oxidative stress and participates in memory formation that could be involved in drug toxicity and addiction mechanisms. Therefore NFkappaB activity, oxidative stress, neuronal nitric oxide synthase (nNOS) activity, spatial learning and memory as well as the effect of topiramate, a previously proposed therapy for cocaine addiction, were evaluated in an experimental model of cocaine administration in rats. NFkappaB activity was decreased in the frontal cortex of cocaine treated rats, as well as GSH concentration and glutathione peroxidase activity in the hippocampus, whereas nNOS activity in the hippocampus was increased. Memory retrieval of experiences acquired prior to cocaine administration was impaired and negatively correlated with NFkappaB activity in the frontal cortex. In contrast, learning of new tasks was enhanced and correlated with the increase of nNOS activity and the decrease of glutathione peroxidase. These results provide evidence for a possible mechanistic role of oxidative and nitrosative stress and NFkappaB in the alterations induced by cocaine. Topiramate prevented all the alterations observed, showing novel neuroprotective properties.

  12. Behavioral effects of deep brain stimulation of different areas of the Papez circuit on memory- and anxiety-related functions.

    PubMed

    Hescham, Sarah; Jahanshahi, Ali; Meriaux, Céline; Lim, Lee Wei; Blokland, Arjan; Temel, Yasin

    2015-10-01

    Deep brain stimulation (DBS) has gained interest as a potential therapy for advanced treatment-resistant dementia. However, possible targets for DBS and the optimal stimulation parameters are not yet clear. Here, we compared the effects of DBS of the CA1 sub-region of the hippocampus, mammillothalamic tract, anterior thalamic nucleus, and entorhinal cortex in an experimental rat model of dementia. Rats with scopolamine-induced amnesia were assessed in the object location task with different DBS parameters. Moreover, anxiety-related side effects were evaluated in the elevated zero maze and open field. After sacrifice, we applied c-Fos immunohistochemistry to assess which memory-related regions were affected by DBS. When comparing all structures, DBS of the entorhinal cortex and CA1 sub-region was able to restore memory loss when a specific set of stimulation parameters was used. No anxiety-related side effects were found following DBS. The beneficial behavioral performance of CA1 DBS rats was accompanied with an activation of cells in the anterior cingulate gyrus. Therefore, we conclude that acute CA1 DBS restores memory loss possibly through improved attentional and cognitive processes in the limbic cortex.

  13. Using cholinergic M1 receptor positive allosteric modulators to improve memory via enhancement of brain cholinergic communication.

    PubMed

    Chambon, Caroline; Jatzke, Claudia; Wegener, Nico; Gravius, Andreas; Danysz, Wojciech

    2012-12-15

    Benzylquinolone carboxylic acid (BQCA) is a recently described cholinergic muscarinic M(1) receptor positive allosteric modulator having potential as cognitive enhancer in dementia. The present study focused on the characterisation of BQCA's mode of action in relation to positive effects on memory and side-effects in an animal model. To get insight into this mode of action, in vitro receptor potency/left shift experiments in cells stably expressing the rat's M(1) receptor were performed. They revealed an inflection point value of BQCA corresponding to 306nM, and potentiation of the agonist response up to 47-fold in presence of 10μM of BQCA. In vivo, brain microdialysis showed a maximal brain level of 270nM, 40min after i.p. administration at 10mg/kg. Based on in vitro data obtained with this dose, it can be concluded that BQCA reaches brain levels which should potentiate the agonist response about 4-fold. Behavioural data confirmed that BQCA used at 10mg/kg attenuated scopolamine-induced memory deficit in a spontaneous alternation task. Moreover, BQCA showed no side effect at 10mg/kg and above in spontaneous locomotion and salivation tests. The profile of BQCA observed in the present study displays a clear advantage over the M(1)-M(3) agonist cevimeline. The present data show the therapeutic potential of the M(1) receptor positive allosteric modulator BQCA for the treatment of memory deficits observed in Alzheimer's disease.

  14. Examining reward-seeking, negative self-beliefs and over-general autobiographical memory as mechanisms of change in classroom prevention programs for adolescent depression

    PubMed Central

    Rice, Frances; Rawal, Adhip; Riglin, Lucy; Lewis, Gemma; Lewis, Glyn; Dunsmuir, Sandra

    2015-01-01

    Background Effective methods to prevent adolescent depressive symptoms could reduce suffering and burden across the lifespan. However, psychological interventions delivered to adolescents show efficacy only in symptomatic or high-risk youth. Targeting causal risk factors and assessing mechanistic change can help devise efficacious universal or classroom based prevention programs. Methods A non-randomized longitudinal design was used to compare three classroom-based prevention programs for adolescent depression (Behavioral Activation with Reward Processing, “Thinking about Reward in Young People” (TRY); Cognitive Behavioral Therapy (CBT) and Mindfulness Based Cognitive Therapy (MBCT)), and determine cognitive mechanisms of change in these programs. Cognitive mechanisms examined were reward-seeking, negative self-beliefs (assessed with behavioral tasks) and over-general autobiographical memory. 256 healthy adolescents aged 13–14 participated with 236 (92%) and 227 (89%) completing the pre- and post-assessments. Results TRY was the only intervention associated with a reduction in depressive symptoms at follow-up. Reward-seeking increased following TRY. In the other programs there were non-significant changes in cognitive mechanisms, with more reflective negative self-beliefs in CBT and fewer over-general autobiographical memories in MBCT In the TRY program, which focused on increasing sensitivity to rewarding activities, reward seeking increased and this was associated with decreased depressive symptoms. Limitations Due to the infeasibility of a cluster randomized controlled trial, a non-randomized design was used. Conclusions Increased reward-seeking was associated with decreased depressive symptoms and may be a mechanism of depressive symptom change in the intervention with a focus on enhancing sensitivity and awareness of reward. This study provides preliminary evidence to suggest that incorporating activities to enhance reward sensitivity may be fruitful in

  15. Gugulipid, an extract of Commiphora whighitii with lipid-lowering properties, has protective effects against streptozotocin-induced memory deficits in mice.

    PubMed

    Saxena, Gunjan; Singh, Sheelendra Pratap; Pal, Raghvendra; Singh, Stayawan; Pratap, Ram; Nath, Chandishwar

    2007-04-01

    Gugulipid, an ethyl acetate extract of the resin of plant Commiphora whighitii is an established hypolipidemic agent in clinical practice. The major constituent of gugulipid is guggulsterone [4, 17 (20)-pregnadiene-3, 16-dione]. It has been observed recently that patients receiving lipid-lowering drugs like statins have a reduced risk of dementia. Therefore, the present study was planned to explore the potential of gugulipid as cognitive enhancer. Gugulipid (12.5, 25 and 50 mg/kg, p.o.) showed dose dependent improvement in scopolamine-induced deficits in passive avoidance test. The maximal effective dose of gugulipid i.e. 50 mg/kg, p.o. was used for further studies on streptozotocin (STZ) model of dementia in mice. Gugulipid was investigated for its effect on learning and memory, parameters of oxidative stress (GSH and MDA) and acetylcholinesterase (AChE) activity in the STZ (ic)-treated mice. Intracerebral (ic) injections of STZ (0.5 mg/kg) on 1st and 3rd day caused significant deficit in memory in passive avoidance and Morris water maze test after the 14th day of first dose. In passive avoidance, transfer latency time (TLT) was not increased on retention trials in STZ (ic) group while gugulipid treatment resulted in significant increase in TLT on retention trials in STZ (ic)-treated mice. In Morris water maze test the latency time to reach platform in STZ (ic)-treated mice was significantly higher than control and vehicle (artificial CSF). Pre-treatment of gugulipid (50 mg/kg, p.o.) daily for 14 days started with the first dose of STZ (ic), significantly prevented STZ (ic)-induced memory deficit. Post-treatment i.e. after 14 days of first dose of STZ (ic) of gugulipid (50 mg/kg, p.o.) significantly decreased the latency time indicating anti-dementia activity. Effect of gugulipid and STZ in visible platform test was similar to those seen with hidden platform. Gugulipid and STZ-treated mice did not cause significant change in locomotor activity. Furthermore, STZ

  16. Short-term green tea supplementation prevents recognition memory deficits and ameliorates hippocampal oxidative stress induced by different stroke models in rats.

    PubMed

    Altermann, Caroline Dalla Colletta; Souza, Mauren Assis; Schimidt, Helen L; Izaguirry, Aryele Pinto; Martins, Alexandre; Garcia, Alexandre; Santos, Francielli W; Mello-Carpes, Pâmela B

    2017-03-19

    This study investigated the effect of green tea (GT) on short and long term declarative memory and oxidative damage induced by transient ischemia-reperfusion (IR) and intracerebral hemorrhage (ICH) in rats. Male Wistar rats were divided into 8 groups of 10 according the stroke type induced: Sham IR, Sham IR+GT, IR, IR+GT, Sham ICH, Sham ICH+GT, ICH, ICH+GT. Supplementation with GT was initiated 10days before stroke surgery and continuous for 6days after (GT dose 400mg/kg). Short (STM) and long term memory (LTM) we evaluated with object recognition task (OR) and hippocampus were used to evaluate parameters related to oxidative stress (ROS, lipid peroxidation and total antioxidant capacity). The rats subjected to IR and ICH showed STM and LTM deficits and GT intervention prevented it in both stroke models. IR and ICH induced increase on ROS levels in hippocampus. ICH increased the lipid peroxidation in hippocampus and the GT supplementation avoided it. IR induced decrease on total antioxidant capacity and GT prevented it. These results reveal that GT supplementation presents a neuroprotective role, attenuates redox imbalance and might have a beneficial impact on cognitive function after stroke.

  17. Prevention of depression and sleep disturbances in elderly with memory-problems by activation of the biological clock with light - a randomized clinical trial

    PubMed Central

    2010-01-01

    Background Depression frequently occurs in the elderly and in patients suffering from dementia. Its cause is largely unknown, but several studies point to a possible contribution of circadian rhythm disturbances. Post-mortem studies on aging, dementia and depression show impaired functioning of the suprachiasmatic nucleus (SCN) which is thought to be involved in the increased prevalence of day-night rhythm perturbations in these conditions. Bright light enhances neuronal activity in the SCN. Bright light therapy has beneficial effects on rhythms and mood in institutionalized moderate to advanced demented elderly. In spite of the fact that this is a potentially safe and inexpensive treatment option, no previous clinical trial evaluated the use of long-term daily light therapy to prevent worsening of sleep-wake rhythms and depressive symptoms in early to moderately demented home-dwelling elderly. Methods/Design This study investigates whether long-term daily bright light prevents worsening of sleep-wake rhythms and depressive symptoms in elderly people with memory complaints. Patients with early Alzheimer's Disease (AD), Mild Cognitive Impairment (MCI) and Subjective Memory Complaints (SMC), between the ages of 50 and 75, are included in a randomized double-blind placebo-controlled trial. For the duration of two years, patients are exposed to ~10,000 lux in the active condition or ~300 lux in the placebo condition, daily, for two half-hour sessions at fixed times in the morning and evening. Neuropsychological, behavioral, physiological and endocrine measures are assessed at baseline and follow-up every five to six months. Discussion If bright light therapy attenuates the worsening of sleep-wake rhythms and depressive symptoms, it will provide a measure that is easy to implement in the homes of elderly people with memory complaints, to complement treatments with cholinesterase inhibitors, sleep medication or anti-depressants or as a stand-alone treatment. Trial

  18. The selective positive allosteric M1 muscarinic receptor modulator PQCA attenuates learning and memory deficits in the Tg2576 Alzheimer's disease mouse model.

    PubMed

    Puri, Vanita; Wang, Xiaohai; Vardigan, Joshua D; Kuduk, Scott D; Uslaner, Jason M

    2015-01-01

    We have recently shown that the M1 muscarinic receptor positive allosteric modulator, PQCA, improves cognitive performance in rodents and non-human primates administered the muscarinic receptor antagonist scopolamine. The purpose of the present experiments was to characterize the effects of PQCA in a model more relevant to the disease pathology of Alzheimer's disease. Tg2576 transgenic mice that have elevated Aβ were tested in the novel object recognition task to characterize recognition memory as a function of age and treatment with the PQCA. The effects of PQCA were compared to the acetylcholinesterase inhibitor donepezil, the standard of care for Alzheimer's disease. In addition, the effect of co-administering PQCA and donepezil was evaluated. Aged Tg2576 mice demonstrated a deficit in recognition memory that was significantly attenuated by PQCA. The positive control donepezil also reversed the deficit. Furthermore, doses of PQCA and donepezil that were inactive on their own were found to improve recognition memory when given together. These studies suggest that M1 muscarinic receptor positive allosteric modulation can ameliorate memory deficits in disease relevant models of Alzheimer's disease. These data, combined with our previous findings demonstrating PQCA improves scopolamine-induced cognitive deficits in both rodents and non-human primates, suggest that M1 positive allosteric modulators have therapeutic potential for the treatment of Alzheimer's disease.

  19. Role of 5-HT6 receptors in memory formation.

    PubMed

    Meneses, A

    2001-09-01

    Mice lacking the 5-HT(6) receptor presented neither gross anatomical or behavioral abnormalities nor obvious changes in microscopic brain morphology, and their performance in rotarod, open field and novel object testing paradigms revealed no differences compared with wild-type animals. Nevertheless, an association between the 5-HT(6) receptor polymorphism C267T and Alzheimer's disease has been reported. Interestingly, the 5-HT(6) antisense oligonucleotide decreased 5-HT(6) gene expression and enhanced spatial learning acquisition in the water maze. Similarly, injection of the 5-HT(6) receptor antagonist Ro-04-6790 improved learning consolidation in an autoshaping task, while mCPP, scopolamine and dizocilpine decreased performance. The effect induced by scopolamine or dizocilpine, but not that induced by mCPP, was completely or partially reversed by Ro-04-6790. Ro-04-6790 did not modify the 8-OH-DPAT facilitatory effects on learning consolidation. Since Ro-04-6790 facilitatory effect was unaffected by 5-HT(1A), 5-HT(2A/2B/2C), 5-HT(3), 5-HT(4) or 5-HT(7) receptor blockade, the facilitatory effect induced by Ro-04-6790 involved specifically 5-HT6 receptors. Similarly, the 5-HT(6) receptor antagonist SB-271046 improved retention in the water maze and produced a significant performance improvement in aged rats in an operant-delayed alternation task. A series of Ro-04-6790 analogues that penetrate the brain and specifically bind to 5-HT(6) receptors reversed scopolamine-induced retention deficit in a passive avoidance learning test. Collectively, these data provide further support to the notion that 5-HT systems, via 5-HT(6) receptors, also play a significant role in memory formation under normal and dysfunctional memory conditions.

  20. Memory Loss: 7 Tips to Improve Your Memory

    MedlinePlus

    ... re not alone. Everyone forgets things occasionally. Still, memory loss is nothing to take lightly. Although there are no guarantees when it comes to preventing memory loss or dementia, certain activities might help. Consider ...

  1. Overexpression of Mineralocorticoid Receptors Partially Prevents Chronic Stress-Induced Reductions in Hippocampal Memory and Structural Plasticity.

    PubMed

    Kanatsou, Sofia; Fearey, Brenna C; Kuil, Laura E; Lucassen, Paul J; Harris, Anjanette P; Seckl, Jonathan R; Krugers, Harm; Joels, Marian

    2015-01-01

    Exposure to chronic stress is a risk factor for cognitive decline and psychopathology in genetically predisposed individuals. Preliminary evidence in humans suggests that mineralocorticoid receptors (MRs) may confer resilience to these stress-related changes. We specifically tested this idea using a well-controlled mouse model for chronic stress in combination with transgenic MR overexpression in the forebrain. Exposure to unpredictable stressors for 21 days in adulthood reduced learning and memory formation in a low arousing hippocampus-dependent contextual learning task, but enhanced stressful contextual fear learning. We found support for a moderating effect of MR background on chronic stress only for contextual memory formation under low arousing conditions. In an attempt to understand potentially contributing factors, we studied structural plasticity. Chronic stress altered dendritic morphology in the hippocampal CA3 area and reduced the total number of doublecortin-positive immature neurons in the infrapyramidal blade of the dentate gyrus. The latter reduction was absent in MR overexpressing mice. We therefore provide partial support for the idea that overexpression of MRs may confer resilience to the effects of chronic stress on hippocampus-dependent function and structural plasticity.

  2. Overexpression of Mineralocorticoid Receptors Partially Prevents Chronic Stress-Induced Reductions in Hippocampal Memory and Structural Plasticity

    PubMed Central

    Kanatsou, Sofia; Fearey, Brenna C.; Kuil, Laura E.; Lucassen, Paul J.; Harris, Anjanette P.; Seckl, Jonathan R.

    2015-01-01

    Exposure to chronic stress is a risk factor for cognitive decline and psychopathology in genetically predisposed individuals. Preliminary evidence in humans suggests that mineralocorticoid receptors (MRs) may confer resilience to these stress-related changes. We specifically tested this idea using a well-controlled mouse model for chronic stress in combination with transgenic MR overexpression in the forebrain. Exposure to unpredictable stressors for 21 days in adulthood reduced learning and memory formation in a low arousing hippocampus-dependent contextual learning task, but enhanced stressful contextual fear learning. We found support for a moderating effect of MR background on chronic stress only for contextual memory formation under low arousing conditions. In an attempt to understand potentially contributing factors, we studied structural plasticity. Chronic stress altered dendritic morphology in the hippocampal CA3 area and reduced the total number of doublecortin-positive immature neurons in the infrapyramidal blade of the dentate gyrus. The latter reduction was absent in MR overexpressing mice. We therefore provide partial support for the idea that overexpression of MRs may confer resilience to the effects of chronic stress on hippocampus-dependent function and structural plasticity. PMID:26600250

  3. Mental space travel: damage to posterior parietal cortex prevents egocentric navigation and reexperiencing of remote spatial memories.

    PubMed

    Ciaramelli, Elisa; Rosenbaum, R Shayna; Solcz, Stephanie; Levine, Brian; Moscovitch, Morris

    2010-05-01

    The ability to navigate in a familiar environment depends on both an intact mental representation of allocentric spatial information and the integrity of systems supporting complementary egocentric representations. Although the hippocampus has been implicated in learning new allocentric spatial information, converging evidence suggests that the posterior parietal cortex (PPC) might support egocentric representations. To date, however, few studies have examined long-standing egocentric representations of environments learned long ago. Here we tested 7 patients with focal lesions in PPC and 12 normal controls in remote spatial memory tasks, including 2 tasks reportedly reliant on allocentric representations (distance and proximity judgments) and 2 tasks reportedly reliant on egocentric representations (landmark sequencing and route navigation; see Rosenbaum, Ziegler, Winocur, Grady, & Moscovitch, 2004). Patients were unimpaired in distance and proximity judgments. In contrast, they all failed in route navigation, and left-lesioned patients also showed marginally impaired performance in landmark sequencing. Patients' subjective experience associated with navigation was impoverished and disembodied compared with that of the controls. These results suggest that PPC is crucial for accessing remote spatial memories within an egocentric reference frame that enables both navigation and reexperiencing. Additionally, PPC was found to be necessary to implement specific aspects of allocentric navigation with high demands on spontaneous retrieval.

  4. Time-course of 5-HT(6) receptor mRNA expression during memory consolidation and amnesia.

    PubMed

    Huerta-Rivas, A; Pérez-García, G; González-Espinosa, C; Meneses, A

    2010-01-01

    Growing evidence indicates that antagonists of the 5-hydroxytryptamine (serotonin) receptor(6) (5-HT(6)) improve memory and reverse amnesia although the mechanisms involved are poorly understood. Hence, in this paper RT-PCR was used to evaluate changes in mRNA expression of 5-HT(6) receptor in trained and untrained rats treated with the 5-HT(6) receptor antagonist SB-399885 and amnesic drugs scopolamine or dizocilpine. Changes in mRNA expression of 5-HT(6) receptor were investigated at different times in prefrontal cortex, hippocampus and striatum. Data indicated that memory in the Pavlovian/instrumental autoshaping task was a progressive process associated to reduced mRNA expression of 5-HT(6) receptor in the three structures examined. SB-399885 improved long-term memory at 48h, while the muscarinic receptor antagonist scopolamine or the non-competitive NMDA receptor antagonist dizocilpine impaired it at 24h. Autoshaping training and treatment with SB-399885 increased 5-HT(6) receptor mRNA expression in (maximum increase) prefrontal cortex and striatum, 24 or 48h. The scopolamine-induced amnesia suppressed 5-HT(6) receptor mRNA expression while the dizocilpine-induced amnesia did not modify 5-HT(6) receptor mRNA expression. SB-399885 and scopolamine or dizocilpine were able to reestablish memory and 5-HT(6) receptor mRNA expression. These data confirmed previous memory evidence and of more interest is the observation that training, SB-399885 and amnesic drugs modulated 5-HT(6) receptor mRNA expression in prefrontal cortex, hippocampus and striatum. Further investigation in different memory tasks, times and amnesia models together with more complex control groups might provide further clues.

  5. Long-term cannabidiol treatment prevents the development of social recognition memory deficits in Alzheimer's disease transgenic mice.

    PubMed

    Cheng, David; Spiro, Adena S; Jenner, Andrew M; Garner, Brett; Karl, Tim

    2014-01-01

    Impairments in cognitive ability and widespread pathophysiological changes caused by neurotoxicity, neuroinflammation, oxidative damage, and altered cholesterol homeostasis are associated with Alzheimer's disease (AD). Cannabidiol (CBD) has been shown to reverse cognitive deficits of AD transgenic mice and to exert neuroprotective, anti-oxidative, and anti-inflammatory properties in vitro and in vivo. Here we evaluate the preventative properties of long-term CBD treatment in male AβPPSwe/PS1ΔE9 (AβPP × PS1) mice, a transgenic model of AD. Control and AD transgenic mice were treated orally from 2.5 months of age with CBD (20 mg/kg) daily for 8 months. Mice were then assessed in the social preference test, elevated plus maze, and fear conditioning paradigms, before cortical and hippocampal tissues were analyzed for amyloid load, oxidative damage, cholesterol, phytosterols, and inflammation. We found that AβPP × PS1 mice developed a social recognition deficit, which was prevented by CBD treatment. CBD had no impact on anxiety or associative learning. The prevention of the social recognition deficit was not associated with any changes in amyloid load or oxidative damage. However, the study revealed a subtle impact of CBD on neuroinflammation, cholesterol, and dietary phytosterol retention, which deserves further investigation. This study is the first to demonstrate CBD's ability to prevent the development of a social recognition deficit in AD transgenic mice. Our findings provide the first evidence that CBD may have potential as a preventative treatment for AD with a particular relevance for symptoms of social withdrawal and facial recognition.

  6. Combination of N-acetylcysteine, α-lipoic acid and α-tocopherol substantially prevents the brain synaptosomal alterations and memory and learning deficits of aged rats.

    PubMed

    Thakurta, Ishita Guha; Banerjee, Priyanjalee; Bagh, Maria Bindu; Ghosh, Arindam; Sahoo, Arghyadip; Chattopadhyay, Sita; Chakrabarti, Sasanka

    2014-02-01

    This study has compared several synaptosomal parameters in three groups of rats: young (46 months), aged (22-24 months) and antioxidant supplemented aged rats (antioxidant supplementation given with the diet as a combination of N-acetylcysteine, α-lipoic acid and α-tocopherol from 18 months onwards till 22-24 months). The synaptosomes from aged rat brain, in comparison to those of young animals, exhibit an increased membrane potential with altered contents of Na(+) and K(+) under basal incubation condition and in the presence of depolarizing agents. The intrasynaptosomal Ca(2+) is also higher in aged than in young rat. These age-dependent changes in synaptosomal parameters are prevented markedly in the antioxidant supplemented group. When examined on T-maze, the aged animals are noticeably impaired in learning and memory functions, but the deficit is remarkably prevented in the antioxidant supplemented aged animals. It is suggested that the synaptosomal alterations partly contribute to the cognitive deficits of aged animals, and both are rescued by long-term antioxidant supplementation.

  7. Lithium chloride administration prevents spatial learning and memory impairment in repeated cerebral ischemia-reperfusion mice by depressing apoptosis and increasing BDNF expression in hippocampus.

    PubMed

    Fan, Mingyue; Jin, Wei; Zhao, Haifeng; Xiao, Yining; Jia, Yanqiu; Yin, Yu; Jiang, Xin; Xu, Jing; Meng, Nan; Lv, Peiyuan

    2015-09-15

    Lithium has been reported to have neuroprotective effects, but the preventive and treated role on cognition impairment and the underlying mechanisms have not been determined. In the present study, C57Bl/6 mice were subjected to repeated bilateral common carotid artery occlusion to induce the learning and memory deficits. 2 mmol/kg or 5 mmol/kg of lithium chloride (LiCl) was injected intraperitoneally per day before (for 7 days) or post (for 28 days) the operation. This repeated cerebral ischemia-reperfusion (IR) induced dynamic overexpression of ratio of Bcl-2/Bax and BDNF in hippocampus of mice. LiCl pretreatment and treatment significantly decreased the escape latency and increased the percentage of time that the mice spent in the target quadrant in Morris water maze. 2 mmol/kg LiCl evidently reversed the morphologic changes, up-regulated the survival neuron count and increased the BDNF gene and protein expression. 5 mmol/kg pre-LiCl significantly increased IR-stimulated reduce of Bcl-2/Bax and p-CREB/CREB. These results described suggest that pre-Li and Li treatment may induce a pronounced prevention on cognitive impairment. These effects may relay on the inhibition of apoptosis and increasing BDNF and p-CREB expression.

  8. Intranasal Delivery of NEMO-Binding Domain Peptide Prevents Memory Loss in a Mouse Model of Alzheimer’s Disease

    PubMed Central

    Rangasamy, Suresh B.; Corbett, Grant T.; Roy, Avik; Modi, Khushbu K.; Bennett, David A.; Mufson, Elliott J.; Ghosh, Sankar; Pahan, Kalipada

    2015-01-01

    Alzheimer’s disease (AD) is the most common form of dementia. Despite intense investigations, no effective therapy is available to halt its progression. We found that NF-κB was activated within the hippocampus and cortex of AD subjects and that activated forms of NF-κB negatively correlated with cognitive function monitored by Mini-Mental State Examination and global cognitive z score. Accordingly, NF-κB activation was also observed in the hippocampus of a transgenic (5XFAD) mouse model of AD. It has been shown that peptides corresponding to the NF-κB essential modifier (NEMO)-binding domain (NBD) of IκB kinase α (IKKα) or IκB kinase β (IKKβ) specifically inhibit the induction of NF-κB activation without inhibiting the basal NF-κB activity. Interestingly, after intranasal administration, wild-type NBD peptide entered into the hippocampus, reduced hippocampal activation of NF-κB, suppressed hippocampal microglial activation, lowered the burden of Aβ in the hippocampus, attenuated apoptosis of hippocampal neurons, protected plasticity-related molecules, and improved memory and learning in 5XFAD mice. Mutated NBD peptide had no such protective effect, indicating the specificity of our finding. These results suggest that selective targeting of NF-κB activation by intranasal administration of NBD peptide may be of therapeutic benefit for AD patients. PMID:26401561

  9. Interleukin-1β-induced memory reconsolidation impairment is mediated by a reduction in glutamate release and zif268 expression and α-melanocyte-stimulating hormone prevented these effects.

    PubMed

    Machado, Ivana; Gonzalez, Patricia V; Vilcaes, Alejandro; Carniglia, Lila; Schiöth, Helgi B; Lasaga, Mercedes; Scimonelli, Teresa N

    2015-05-01

    The immune system is an important modulator of learning, memory and neural plasticity. Interleukin 1β (IL-1β), a pro-inflammatory cytokine, significantly affects several cognitive processes. Previous studies by our group have demonstrated that intrahippocampal administration of IL-1β impairs reconsolidation of contextual fear memory. This effect was reversed by the melanocortin alpha-melanocyte-stimulating hormone (α-MSH). The mechanisms underlying the effect of IL-1β on memory reconsolidation have not yet been established. Therefore, we examined the effect of IL-1β on glutamate release, ERK phosphorylation and the activation of the transcription factor zinc finger- 268 (zif268) during reconsolidation. Our results demonstrated that IL-1β induced a significant decrease of glutamate release after reactivation of the fear memory and this effect was related to calcium concentration in hippocampal synaptosomes. IL-1β also reduced ERK phosphorylation and zif268 expression in the hippocampus. Central administration of α-MSH prevented the decrease in glutamate release, ERK phosphorylation and zif268 expression induced by IL-1β. Our results establish possible mechanisms involved in the detrimental effect of IL-1β on memory reconsolidation and also indicate that α-MSH may exert a beneficial modulatory role in preventing IL-1β effects.

  10. Lidocaine Injections Targeting CA3 Hippocampus Impair Long-Term Spatial Memory and Prevent Learning-Induced Mossy Fiber Remodeling

    PubMed Central

    Holahan, Matthew R.; Routtenberg, Aryeh

    2010-01-01

    Learning a spatial location induces remodeling of the mossy fiber terminal field (MFTF) in the CA3 subfield of the dorsal hippocampus (Holahan et al., 2006; Ramirez-Amaya et al., 2001; Rekart et al., 2007a). These fibers appear to grow from the stratum lucidum (SL) into distal stratum oriens (dSO). Is this axonal growth dependent on ‘repeated and persistent’ neural activity in the CA3 region during training? To address this issue, we targeted local inactivation of the MFTF region in a post-training, consolidation paradigm. Male Wistar rats, bilaterally implanted with chronic indwelling cannulae aimed at the MFTF CA3 region, were trained on a hidden platform water maze task (10 trials per day for 5 days). Immediately after the 10th trial on each training day, rats were injected with lidocaine (4% w/V; 171 mM; n = 7) or phosphate-buffered saline (PBS; n = 7). Behavioral measures of latency, path length and thigmotaxis were recorded, as was directional heading. A retention test (probe trial) was given 7 days after the last training day and brains were subsequently processed for MFTF distribution (Timm’s stain) and cannula location. Lidocaine treatment was found to block the learning-associated structural remodeling of the MFTF that was reported previously and observed in the PBS-injected controls. During training, the lidocaine group showed elevated latencies and a misdirected heading to locate the platform on the first trial of each training day. On the 7-day retention probe trial, the lidocaine-injected group showed poor retention indicated by the absence of a search bias in the area where the platform had been located during training. These data suggest that reduction of neuronal activity in the CA3 region impairs long-term storage of spatial information. As this was associated with reduced MFTF structural remodeling, it provides initial anatomical and behavioral evidence for an activity – dependent, presynaptic growth model of memory. PMID:20865723

  11. Angelica gigas Nakai and Soluplus-Based Solid Formulations Prepared by Hot-Melting Extrusion: Oral Absorption Enhancing and Memory Ameliorating Effects.

    PubMed

    Piao, Jingpei; Lee, Jae-Young; Weon, Jin Bae; Ma, Choong Je; Ko, Hyun-Jeong; Kim, Dae-Duk; Kang, Wie-Soo; Cho, Hyun-Jong

    2015-01-01

    Oral solid formulations based on Angelica gigas Nakai (AGN) and Soluplus were prepared by the hot-melting extrusion (HME) method. AGN was pulverized into coarse and ultrafine particles, and their particle size and morphology were investigated. Ultrafine AGN particles were used in the HME process with high shear to produce AGN-based formulations. In simulated gastrointestinal fluids (pH 1.2 and pH 6.8) and water, significantly higher amounts of the major active components of AGN, decursin (D) and decursinol angelate (DA), were extracted from the HME-processed AGN/Soluplus (F8) group than the AGN EtOH extract (ext) group (p < 0.05). Based on an in vivo pharmacokinetic study in rats, the relative oral bioavailability of decursinol (DOH), a hepatic metabolite of D and DA, in F8-administered mice was 8.75-fold higher than in AGN EtOH ext-treated group. In scopolamine-induced memory-impaired mice, F8 exhibited a more potent cognitive enhancing effect than AGN EtOH ext in both a Morris water maze test and a passive avoidance test. These findings suggest that HME-processed AGN/Soluplus formulation (F8) could be a promising therapeutic candidate for memory impairment.

  12. Improvement in Long-Term Memory following Chronic Administration of Eryngium planum Root Extract in Scopolamine Model: Behavioral and Molecular Study

    PubMed Central

    Ozarowski, Marcin; Thiem, Barbara; Mikolajczak, Przemyslaw L.; Piasecka, Anna; Kachlicki, Piotr; Szulc, Michal; Kaminska, Ewa; Bogacz, Anna; Kujawski, Radoslaw; Bartkowiak-Wieczorek, Joanna; Kujawska, Malgorzata; Jodynis-Liebert, Jadwiga; Budzianowski, Jaromir; Kędziora, Izabela; Seremak-Mrozikiewicz, Agnieszka; Czerny, Boguslaw; Bobkiewicz-Kozłowska, Teresa

    2015-01-01

    Eryngium planum L. (EP) is as a rare medicinal plant with a lot of potentials as pharmaceutical crops. The aim of our study was to assess the effect of subchronic (28-fold) administration of a 70% ethanol extract of EP roots (200 mg/kg, p.o.) on behavioral and cognitive responses in Wistar rats linked with acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and beta-secretase (BACE-1) mRNA levels and AChE and BuChE activities in the hippocampus and frontal cortex. On the last day of experiment, 30 min after the last dose of EP or Huperzine A (HU), scopolamine (SC) was given at a dose of 0.5 mg/kg b.w. intraperitoneally. The results of a passive avoidance test showed an improvement in long-term memory produced by the EP extract in both scopolamine-induced rats and control group. EP caused an insignificant inhibition of AChE and BuChE activities in the frontal cortex and the hippocampus. EP decreased mRNA AChE, BuChE, and BACE-1 levels, especially in the cortex. Our results suggest that the EP extract led to the improvement of the long-term memory in rats coupled with total saponin content. The mechanism of EP action is probably complicated, since HPLC-MS analysis showed 64 chemical compounds (phenolics, saponins) in the extract of EP roots. PMID:26483842

  13. Lactobacillus pentosus var. plantarum C29 ameliorates memory impairment and inflammaging in a D-galactose-induced accelerated aging mouse model.

    PubMed

    Woo, Jae-Yeon; Gu, Wan; Kim, Kyung-Ah; Jang, Se-Eun; Han, Myung Joo; Kim, Dong-Hyun

    2014-06-01

    Aging is associated with Alzheimer's disease (AD), cardiovascular disease and cancer. Oxidative stress is considered as a major factor that accelerates the aging process. To understand the ability of lactic acid bacteria to ameliorate memory impairment caused by aging, we investigated the effect of Lactobacillus pentosus var. plantarum (C29), which is known to protect against scopolamine-induced memory impairment, on oxidative stress (D-galactose)-induced memory impairment in mice. D-Galactose was subcutaneously injected to 20-week old male C57BL/6J mice for 10 weeks, with oral administration of C29 for the final 5 weeks. Excessive intake of D-galactose not only impaired memory, which was indicated by passive avoidance, Y-maze, and Morris water-maze tasks, but also reduced the expression of brain-derived neurotrophic factor (BDNF) and hippocampal doublecortin (DCX) and the activation of cAMP response element-binding protein (CREB). C29 treatment ameliorated D-galactose-induced memory impairment and reversed the suppression of BDNF and DCX expression and CREB activation. Moreover, C29 decreased the expression of a senescence marker p16 and inflammation markers p-p65, p-FOXO3a, cyclooxygenase (COX)-2, and inducible NO synthase (iNOS). C29 treatment inhibited D-galactose-induced expression of M1 polarization markers tumor necrosis factor-α and arginase II, and attenuated the d-galactose-suppressed expression of M2 markers IL-10, arginase I and CD206. Taken together, these findings suggest that C29 may ameliorate memory impairment and M1 macrophage-polarized inflammation caused by aging.

  14. Mechanical memory

    DOEpatents

    Gilkey, Jeffrey C.; Duesterhaus, Michelle A.; Peter, Frank J.; Renn, Rosemarie A.; Baker, Michael S.

    2006-08-15

    A first-in-first-out (FIFO) microelectromechanical memory apparatus (also termed a mechanical memory) is disclosed. The mechanical memory utilizes a plurality of memory cells, with each memory cell having a beam which can be bowed in either of two directions of curvature to indicate two different logic states for that memory cell. The memory cells can be arranged around a wheel which operates as a clocking actuator to serially shift data from one memory cell to the next. The mechanical memory can be formed using conventional surface micromachining, and can be formed as either a nonvolatile memory or as a volatile memory.

  15. Mechanical memory

    DOEpatents

    Gilkey, Jeffrey C.; Duesterhaus, Michelle A.; Peter, Frank J.; Renn, Rosemarie A.; Baker, Michael S.

    2006-05-16

    A first-in-first-out (FIFO) microelectromechanical memory apparatus (also termed a mechanical memory) is disclosed. The mechanical memory utilizes a plurality of memory cells, with each memory cell having a beam which can be bowed in either of two directions of curvature to indicate two different logic states for that memory cell. The memory cells can be arranged around a wheel which operates as a clocking actuator to serially shift data from one memory cell to the next. The mechanical memory can be formed using conventional surface micromachining, and can be formed as either a nonvolatile memory or as a volatile memory.

  16. [Effect of improving memory and inhibiting acetylcholinesterase activity by invigorating-qi and warming-yang recipe].

    PubMed

    Liu, Z Y; Yang, Y G; Zheng, B

    1993-11-01

    Invigorating-Qi and Warming-Yang (IQWY) had a good curative effect to some senile diseases such as senile dementia, senile hypomnesia etc. This experiment was designed for probing into the therapeutical mechanism of IQWY recipe. BALB/C pure bred mice were divided into five groups. Group I was taken per os of invigorating Qi (IQ), Group II warming Yang (WY), Group III IQWY drugs, Group IV was dysmnesia model, and Group V blank control group injected with normal saline only. All groups except Group V were injected scopolamine (5mg/kg) intraperitoneally to induce dysmnesia model after medication. IQ drug consisted of Codonopsis pilosula, Astragalus membranaceus, Poria cocos, and Glycyrrhiza uralensis, WY drug of Cynomorium songoricum, Epimedium brevicornum and Cuscuta chinensis, while IQWY recipe consisted of both IQ and WY drugs. The results showed that IQ, WY and IQWY had an evident antagonistic action to Scopolamine induced dysmnesia mice, and could improve their memory. The erroneous times of the animal's reaction in Group I, II and III were less than those in Group IV, P < 0.05 or P < 0.01. Acetylcholinesterase (AchE) activity in the mice could be inhibited by IQ, WY and IQWY also. The activity in Group I, II and III was less than that in Group IV and V, P < 0.05 or P < 0.01. The therapeutic mechanism of IQWY was in connection with its effect to M-cholinergic transmitters of central nervous system.

  17. Role of molecular isoforms of acetylcholinesterase in learning and memory functions.

    PubMed

    Das, Amitava; Dikshit, Madhu; Nath, Chandishwar

    2005-05-01

    In the present study, activity of salt soluble (SS) G1 and detergent soluble (DS) G4 molecular isoforms of acetylcholinesterase (AChE) has been investigated in rat brain areas in trained (learned), scopolamine (amnesic) and Tacrine (anti-dementic) treated rats to find out their role in learning and memory functions. AChE was estimated spectrophotometrically at 412 nm in rat brain areas. Isolation and partial purification of molecular isoforms G1 and G4 of AChE was done by gel filtration chromatography. Passive avoidance was used to test learning and memory functions. AChE activity was altered in both the fractions SS and DS of different brain areas following passive avoidance in control, scopolamine treated, tacrine treated and tacrine treatment in scopolamine pretreated rats. The peak AChE activity obtained in the DS (fraction 9) and the SS (fraction 13) fraction following gel filtration chromatography. On the basis of molecular weight fraction 9 (DS) and 13 (SS) represent the G4 and G1, respectively. The pattern of changes in the AChE activity of G1 isoform (fraction 13 of SS) and G4 isoform (fraction 9 of DS) in brain areas were similar to those of SS and DS fraction, respectively. In hippocampus, AChE activity in the fraction G1 isoform (fraction 13 of SS) was decreased only in tacrine treated rats but AChE activity in the G4 isoform (fraction 9 of DS) was decreased in both trained and tacrine treated rats. Changes in activity of G4 isoform of AChE in hippocampus could be correlated with passive avoidance learning, scopolamine induced deficit in passive avoidance and reversal of scopolamine deficit by tacrine.

  18. Cholinesterase inhibitors improve both memory and complex learning in aged beagle dogs.

    PubMed

    Araujo, Joseph A; Greig, Nigel H; Ingram, Donald K; Sandin, Johan; de Rivera, Christina; Milgram, Norton W

    2011-01-01

    Similar to patients with Alzheimer's disease (AD), dogs exhibit age-dependent cognitive decline, amyloid-β (Aβ) pathology, and evidence of cholinergic hypofunction. The present study sought to further investigate the role of cholinergic hypofunction in the canine model by examining the effect of the cholinesterase inhibitors phenserine and donepezil on performance of two tasks, a delayed non-matching-to-position task (DNMP) designed to assess working memory, and an oddity discrimination learning task designed to assess complex learning, in aged dogs. Phenserine (0.5 mg/kg; PO) significantly improved performance on the DNMP at the longest delay compared to wash-out and partially attenuated scopolamine-induced deficits (15 μg/kg; SC). Phenserine also improved learning on a difficult version of an oddity discrimination task compared to placebo, but had no effect on an easier version. We also examined the effects of three doses of donepezil (0.75, 1.5, and 6 mg/kg; PO) on performance of the DNMP. Similar to the results with phenserine, 1.5 mg/kg of donepezil improved performance at the longest delay compared to baseline and wash-out, indicative of memory enhancement. These results further extend the findings of cholinergic hypofunction in aged dogs and provide pharmacological validation of the canine model with a cholinesterase inhibitor approved for use in AD. Collectively, these studies support utilizing the aged dog in future screening of therapeutics for AD, as well as for investigating the links among cholinergic function, Aβ pathology, and cognitive decline.

  19. Acetyl-L-Carnitine via Upegulating Dopamine D1 Receptor and Attenuating Microglial Activation Prevents Neuronal Loss and Improves Memory Functions in Parkinsonian Rats.

    PubMed

    Singh, Sonu; Mishra, Akanksha; Srivastava, Neha; Shukla, Rakesh; Shukla, Shubha

    2016-12-14

    Parkinson's disease is accompanied by nonmotor symptoms including cognitive impairment, which precede the onset of motor symptoms in patients and are regulated by dopamine (DA) receptors and the mesocorticolimbic pathway. The relative contribution of DA receptors and astrocytic glutamate transporter (GLT-1) in cognitive functions is largely unexplored. Similarly, whether microglia-derived increased immune response affects cognitive functions and neuronal survival is not yet understood. We have investigated the effect of acetyl-L-carnitine (ALCAR) on cognitive functions and its possible underlying mechanism of action in 6-hydroxydopamine (6-OHDA)-induced hemiparkinsonian rats. ALCAR treatment in 6-OHDA-lesioned rats improved memory functions as confirmed by decreased latency time and path length in the Morris water maze test. ALCAR further enhanced D1 receptor levels without altering D2 receptor levels in the hippocampus and prefrontal cortex (PFC) regions, suggesting that the D1 receptor is preferentially involved in the regulation of cognitive functions. ALCAR attenuated microglial activation and release of inflammatory mediators through balancing proinflammatory and anti-inflammatory cytokines, which subsequently enhanced the survival of mature neurons in the CA1, CA3, and PFC regions and improved cognitive functions in hemiparkinsonian rats. ALCAR treatment also improved glutathione (GSH) content, while decreasing oxidative stress indices, inducible nitrogen oxide synthase (iNOS) levels, and astrogliosis resulting in the upregulation of GLT-1 levels. Additionally, ALCAR prevented the loss of dopaminergic (DAergic) neurons in ventral tagmental area (VTA)/substantia nigra pars compacta (SNpc) regions of 6-OHDA-lesioned rats, thus maintaining the integrity of the nigrostriatal pathway. Together, these results demonstrate that ALCAR treatment in hemiparkinsonian rats ameliorates neurodegeneration and cognitive deficits, hence suggesting its therapeutic potential in

  20. Memory Matters

    MedlinePlus

    ... different parts. Some of them are important for memory. The hippocampus (say: hih-puh-KAM-pus) is one of the more important parts of the brain that processes memories. Old information and new information, or memories, are ...

  1. Subclinical Doses of ATP-Sensitive Potassium Channel Modulators Prevent Alterations in Memory and Synaptic Plasticity Induced by Amyloid-β.

    PubMed

    Salgado-Puga, Karla; Rodríguez-Colorado, Javier; Prado-Alcalá, Roberto A; Peña-Ortega, Fernando

    2017-02-10

    In addition to coupling cell metabolism and excitability, ATP-sensitive potassium channels (KATP) are involved in neural function and plasticity. Moreover, alterations in KATP activity and expression have been observed in Alzheimer's disease (AD) and during amyloid-β (Aβ)-induced pathology. Thus, we tested whether KATP modulators can influence Aβ-induced deleterious effects on memory, hippocampal network function, and plasticity. We found that treating animals with subclinical doses (those that did not change glycemia) of a KATP blocker (Tolbutamide) or a KATP opener (Diazoxide) differentially restrained Aβ-induced memory deficit, hippocampal network activity inhibition, and long-term synaptic plasticity unbalance (i.e., inhibition of LTP and promotion of LTD). We found that the protective effect of Tolbutamide against Aβ-induced memory deficit was strong and correlated with the reestablishment of synaptic plasticity balance, whereas Diazoxide treatment produced a mild protection against Aβ-induced memory deficit, which was not related to a complete reestablishment of synaptic plasticity balance. Interestingly, treatment with both KATP modulators renders the hippocampus resistant to Aβ-induced inhibition of hippocampal network activity. These findings indicate that KATP are involved in Aβ-induced pathology and they heighten the potential role of KATP modulation as a plausible therapeutic strategy against AD.

  2. Control of Interference during Working Memory Updating

    ERIC Educational Resources Information Center

    Szmalec, Arnaud; Verbruggen, Frederick; Vandierendonck, Andre; Kemps, Eva

    2011-01-01

    The current study examined the nature of the processes underlying working memory updating. In 4 experiments using the n-back paradigm, the authors demonstrate that continuous updating of items in working memory prevents strong binding of those items to their contexts in working memory, and hence leads to an increased susceptibility to proactive…

  3. Prophylactic Subacute Administration of Zinc Increases CCL2, CCR2, FGF2, and IGF-1 Expression and Prevents the Long-Term Memory Loss in a Rat Model of Cerebral Hypoxia-Ischemia

    PubMed Central

    Blanco-Alvarez, Victor Manuel; Soto-Rodriguez, Guadalupe; Gonzalez-Barrios, Juan Antonio; Martinez-Fong, Daniel; Brambila, Eduardo; Torres-Soto, Maricela; Aguilar-Peralta, Ana Karina; Gonzalez-Vazquez, Alejandro; Tomás-Sanchez, Constantino; Limón, I. Daniel; Eguibar, Jose R.; Ugarte, Araceli; Hernandez-Castillo, Jeanett; Leon-Chavez, Bertha Alicia

    2015-01-01

    Prophylactic subacute administration of zinc decreases lipoperoxidation and cell death following a transient cerebral hypoxia-ischemia, thus suggesting neuroprotective and preconditioning effects. Chemokines and growth factors are also involved in the neuroprotective effect in hypoxia-ischemia. We explored whether zinc prevents the cerebral cortex-hippocampus injury through regulation of CCL2, CCR2, FGF2, and IGF-1 expression following a 10 min of common carotid artery occlusion (CCAO). Male rats were grouped as follows: (1) Zn96h, rats injected with ZnCl2 (one dose every 24 h during four days); (2) Zn96h + CCAO, rats treated with ZnCl2 before CCAO; (3) CCAO, rats with CCAO only; (4) Sham group, rats with mock CCAO; and (5) untreated rats. The cerebral cortex-hippocampus was dissected at different times before and after CCAO. CCL2/CCR2, FGF2, and IGF-1 expression was assessed by RT-PCR and ELISA. Learning in Morris Water Maze was achieved by daily training during 5 days. Long-term memory was evaluated on day 7 after learning. Subacute administration of zinc increased expression of CCL2, CCR2, FGF2, and IGF-1 in the early and late phases of postreperfusion and prevented the CCAO-induced memory loss in the rat. These results might be explained by the induction of neural plasticity because of the expression of CCL2 and growth factors. PMID:26355725

  4. Memory Matters

    MedlinePlus

    ... blood vessel (which carries the blood) bursts. continue Brain Injuries Affect Memory At any age, an injury to ... with somebody's memory. Some people who recover from brain injuries need to learn old things all over again, ...

  5. Memory Dysfunction

    PubMed Central

    Matthews, Brandy R.

    2015-01-01

    Purpose of Review: This article highlights the dissociable human memory systems of episodic, semantic, and procedural memory in the context of neurologic illnesses known to adversely affect specific neuroanatomic structures relevant to each memory system. Recent Findings: Advances in functional neuroimaging and refinement of neuropsychological and bedside assessment tools continue to support a model of multiple memory systems that are distinct yet complementary and to support the potential for one system to be engaged as a compensatory strategy when a counterpart system fails. Summary: Episodic memory, the ability to recall personal episodes, is the subtype of memory most often perceived as dysfunctional by patients and informants. Medial temporal lobe structures, especially the hippocampal formation and associated cortical and subcortical structures, are most often associated with episodic memory loss. Episodic memory dysfunction may present acutely, as in concussion; transiently, as in transient global amnesia (TGA); subacutely, as in thiamine deficiency; or chronically, as in Alzheimer disease. Semantic memory refers to acquired knowledge about the world. Anterior and inferior temporal lobe structures are most often associated with semantic memory loss. The semantic variant of primary progressive aphasia (svPPA) is the paradigmatic disorder resulting in predominant semantic memory dysfunction. Working memory, associated with frontal lobe function, is the active maintenance of information in the mind that can be potentially manipulated to complete goal-directed tasks. Procedural memory, the ability to learn skills that become automatic, involves the basal ganglia, cerebellum, and supplementary motor cortex. Parkinson disease and related disorders result in procedural memory deficits. Most memory concerns warrant bedside cognitive or neuropsychological evaluation and neuroimaging to assess for specific neuropathologies and guide treatment. PMID:26039844

  6. Memory protection

    NASA Technical Reports Server (NTRS)

    Denning, Peter J.

    1988-01-01

    Accidental overwriting of files or of memory regions belonging to other programs, browsing of personal files by superusers, Trojan horses, and viruses are examples of breakdowns in workstations and personal computers that would be significantly reduced by memory protection. Memory protection is the capability of an operating system and supporting hardware to delimit segments of memory, to control whether segments can be read from or written into, and to confine accesses of a program to its segments alone. The absence of memory protection in many operating systems today is the result of a bias toward a narrow definition of performance as maximum instruction-execution rate. A broader definition, including the time to get the job done, makes clear that cost of recovery from memory interference errors reduces expected performance. The mechanisms of memory protection are well understood, powerful, efficient, and elegant. They add to performance in the broad sense without reducing instruction execution rate.

  7. Memory Metals

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Under contract to NASA during preparations for the space station, Memry Technologies Inc. investigated shape memory effect (SME). SME is a characteristic of certain metal alloys that can change shape in response to temperature variations. In the late 1980s and early 1990s, Memry used its NASA-acquired expertise to produce a line of home and industrial safety products, and refined the technology in the mid-1990s. Among the new products they developed are three MemrySafe units which prevent scalding from faucets. Each system contains a small valve that reacts to temperature, not pressure. When the water reaches dangerous temperatures, the unit reduces the flow to a trickle; when the scalding temperature subsides, the unit restores normal flow. Other products are the FIRECHEK 2 and 4, heat-activated shutoff valves for industrial process lines, which sense excessive heat and cut off pneumatic pressure. The newest of these products is Memry's Demand Management Water Heater which shifts the electricity requirement from peak to off-peak demands, conserving energy and money.

  8. Flashbulb Memories

    PubMed Central

    Hirst, William; Phelps, Elizabeth A.

    2015-01-01

    We review and analyze the key theories, debates, findings, and omissions of the existing literature on flashbulb memories (FBMs), including what factors affect their formation, retention, and degree of confidence. We argue that FBMs do not require special memory mechanisms and are best characterized as involving both forgetting and mnemonic distortions, despite a high level of confidence. Factual memories for FBM-inducing events generally follow a similar pattern. Although no necessary and sufficient factors straightforwardly account for FBM retention, media attention particularly shapes memory for the events themselves. FBMs are best characterized in term of repetitions, even of mnemonic distortions, whereas event memories evidence corrections. The bearing of this literature on social identity and traumatic memories is also discussed. PMID:26997762

  9. Virtual memory

    NASA Technical Reports Server (NTRS)

    Denning, P. J.

    1986-01-01

    Virtual memory was conceived as a way to automate overlaying of program segments. Modern computers have very large main memories, but need automatic solutions to the relocation and protection problems. Virtual memory serves this need as well and is thus useful in computers of all sizes. The history of the idea is traced, showing how it has become a widespread, little noticed feature of computers today.

  10. Skilled Memory.

    DTIC Science & Technology

    1980-11-06

    Morse code (Bryan & Harter , 1899). In every case, memory performance of the expert seems to violate the established limits of short- term memory. How is...of immediate memory. Quarterly Journal of Experimental psychology, 1958, 10, 12-21. Bryan, W. L., & Harter N. psychological Review, 1899, 6, 345-375...16, 1980 Page 5 Civil Govt Non Govt Dr. Susan Chipman 1 Dr. John R. Anderson Learning and Development Department of Psychology National Institute of

  11. The Mitochondria-Targeted Antioxidant MitoQ Prevents Loss of Spatial Memory Retention and Early Neuropathology in a Transgenic Mouse Model of Alzheimer’s Disease

    PubMed Central

    McManus, Meagan J.; Murphy, Michael P.; Franklin, James L.

    2012-01-01

    Considerable evidence suggests that mitochondrial dysfunction and oxidative stress contribute to the progression of Alzheimer’s disease (AD). We examined the ability of the novel mitochondria-targeted antioxidant MitoQ (mitoquinone mesylate: [10-(4,5-dimethoxy-2-methyl-3,6-dioxo-1,4-cycloheexadienlyl) decyl triphenylphosphonium methanesulfonate]) to prevent AD-like pathology in mouse cortical neurons in cell culture and in a triple transgenic mouse model of AD (3xTg-AD). MitoQ attenuated β-amyloid (Aβ)-induced neurotoxicity in cortical neurons and also prevented increased production of reactive species and loss of mitochondrial membrane potential (Δψm) in them. To determine whether the mitochondrial protection conferred by MitoQ was sufficient to prevent the emergence of AD-like neuropathology in vivo, we treated young female 3xTg-AD mice with MitoQ for 5 months and analyzed the effect on the progression of AD-like pathologies. Our results show that MitoQ prevented cognitive decline in these mice as well as oxidative stress, Aβ accumulation, astrogliosis, synaptic loss, and caspase activation in their brains. The work presented herein suggests a central role for mitochondria in neurodegeneration and provides evidence supporting the use of mitochondria-targeted therapeutics in diseases involving oxidative stress and metabolic failure, namely AD. PMID:22049413

  12. Pre-existing vector immunity does not prevent replication deficient adenovirus from inducing efficient CD8 T-cell memory and recall responses.

    PubMed

    Steffensen, Maria Abildgaard; Jensen, Benjamin Anderschou Holbech; Holst, Peter Johannes; Bassi, Maria Rosaria; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup

    2012-01-01

    Adenoviral vectors have shown a great potential for vaccine development due to their inherent ability to induce potent and protective CD8 T-cell responses. However, a critical issue regarding the use of these vectors is the existence of inhibitory immunity against the most commonly used Ad5 vector in a large part of the human population. We have recently developed an improved adenoviral vaccine vector system in which the vector expresses the transgene tethered to the MHC class II associated invariant chain (Ii). To further evaluate the potential of this system, the concept of pre-existing inhibitory immunity to adenoviral vectors was revisited to investigate whether the inhibition previously seen with the Ad5 vector also applied to the optimized vector system. We found this to be the case, and antibodies dominated as the mechanism underlying inhibitory vector immunity. However, presence of CD8 T cells directed against epitopes in the adenoviral vector seemed to correlate with repression of the induced response in re-vaccinated B-cell deficient mice. More importantly, despite a repressed primary effector CD8 T-cell response in Ad5-immune animals subjected to vaccination, memory T cells were generated that provided the foundation for an efficient recall response and protection upon subsequent viral challenge. Furthermore, the transgene specific response could be efficiently boosted by homologous re-immunization. Taken together, these studies indicate that adenoviral vectors can be used to induce efficient CD8 T-cell memory even in individuals with pre-existing vector immunity.

  13. An Intranasal Formulation of Erythropoietin (Neuro-EPO) Prevents Memory Deficits and Amyloid Toxicity in the APPSwe Transgenic Mouse Model of Alzheimer's Disease.

    PubMed

    Rodríguez Cruz, Yamila; Strehaiano, Manon; Rodríguez Obaya, Teresita; García Rodríguez, Julío César; Maurice, Tangui

    2017-01-01

    Erythropoietin (EPO) is a cytokine known to have effective cytoprotective action in the brain, particularly in ischemic, traumatic, inflammatory, and neurodegenerative conditions. We previously reported the neuroprotective effect of a low sialic form of EPO, Neuro-EPO, applied intranasally in rodent models of stroke or cerebellar ataxia and in a non-transgenic mouse model of Alzheimer's disease (AD). Here we analyzed the protective effect of Neuro-EPO in APPSwe mice, a reference transgenic mouse model of AD. Mice were administered 3 times a day, 3 days in the week with Neuro-EPO (125, 250 μg/kg) intranasally, between 12 and 14 months of age. Motor responses, general activity, and memory responses were analyzed during and after treatment. The deficits in spontaneous alternation, place learning in the water-maze, and novel object recognition observed in APPSwe mice were alleviated by the low dose of Neuro-EPO. Oxidative stress, neuroinflammation, trophic factor levels, and a synaptic marker were analyzed in the hippocampus or cortex of the animals. The increases in lipid peroxidation or in GFAP and Iba-1 contents in APPSwe mice were significantly reduced after Neuro-EPO. Activation of intrinsic and extrinsic apoptotic pathways was analyzed. The increases in Bax/Bcl-2 ratio, TNFα, or Fas ligand levels observed in APPSwe mice were reduced by Neuro-EPO. Finally, immunohistochemical and ELISA analyses of Aβ1-42 levels in the APPSwe mouse cortex and hippocampus showed a marked reduction in Aβ deposits and in soluble and insoluble Aβ1-42 forms. This study therefore confirmed the neuroprotective activity of EPO, particularly for an intranasally deliverable formulation, devoid of erythropoietic side effects, in a transgenic mouse model of AD. Neuro-EPO alleviated memory alterations, oxidative stress, neuroinflammation, apoptosis induction, and amyloid load in 14-month-old APPSwe mice.

  14. Episodic Memories

    ERIC Educational Resources Information Center

    Conway, Martin A.

    2009-01-01

    An account of episodic memories is developed that focuses on the types of knowledge they represent, their properties, and the functions they might serve. It is proposed that episodic memories consist of "episodic elements," summary records of experience often in the form of visual images, associated to a "conceptual frame" that provides a…

  15. Collaging Memories

    ERIC Educational Resources Information Center

    Wallach, Michele

    2011-01-01

    Even middle school students can have memories of their childhoods, of an earlier time. The art of Romare Bearden and the writings of Paul Auster can be used to introduce ideas about time and memory to students and inspire works of their own. Bearden is an exceptional role model for young artists, not only because of his astounding art, but also…

  16. Allopregnanolone prevents memory impairment: effect on mRNA expression and enzymatic activity of hippocampal 3-α hydroxysteroid oxide-reductase.

    PubMed

    Escudero, Carla; Casas, Sebastián; Giuliani, Fernando; Bazzocchini, Vanesa; García, Sebastián; Yunes, Roberto; Cabrera, Ricardo

    2012-02-10

    In this work we investigated how the neurosteroid allopregnanolone can modulate learning and memory processes. For this purpose, we used ovariectomized (OVX) rats subcutaneously injected with oestradiol benzoate (E) alone or E and progesterone (P). Then, rats were injected in dorsal hippocampus with allopregnanolone or vehicle. Animals were tested in inhibitory avoidance task (IA task). After behavioural test hippocampal mRNA expression and enzymatic activity of 3α-HOR, the enzyme responsible of allopregnanolone synthesis, were analysed. In IA task OVX-EP rats spent less time on platform, compared to those OVX or OVX-E. Regression analyses revealed that there was a significant negative relationship between E-P infusion and performance in this task. Pre-training allopregnanolone administration to OVX-EP rats increased the time spent on the platform. Interestingly, when enzymatic activity of 3α-HOR was tested, OVX-EP rats showed a significant decrease in the enzymatic activity, compared with OVX and OVX-E rats. In addition, OVX-EP group showed a significant increase in the enzymatic activity after intrahippocampal infusion of allopregnanolone. On the other hand, when mRNA expression of 3α-HOR was analysed no differences were observed when the hippocampal allopregnanolone injection was done. These results suggest that E and P have amnesic effects on female rats, being reversed by allopregnanolone through its modulation on hippocampal 3α-HOR activity.

  17. Memory conformity affects inaccurate memories more than accurate memories.

    PubMed

    Wright, Daniel B; Villalba, Daniella K

    2012-01-01

    After controlling for initial confidence, inaccurate memories were shown to be more easily distorted than accurate memories. In two experiments groups of participants viewed 50 stimuli and were then presented with these stimuli plus 50 fillers. During this test phase participants reported their confidence that each stimulus was originally shown. This was followed by computer-generated responses from a bogus participant. After being exposed to this response participants again rated the confidence of their memory. The computer-generated responses systematically distorted participants' responses. Memory distortion depended on initial memory confidence, with uncertain memories being more malleable than confident memories. This effect was moderated by whether the participant's memory was initially accurate or inaccurate. Inaccurate memories were more malleable than accurate memories. The data were consistent with a model describing two types of memory (i.e., recollective and non-recollective memories), which differ in how susceptible these memories are to memory distortion.

  18. Exendin-4, a glucagon-like peptide-1 receptor agonist prevents mTBI-induced changes in hippocampus gene expression and memory deficits in mice

    PubMed Central

    Tweedie, D.; Rachmany, L.; Rubovitch, V.; Lehrmann, E.; Zhang, Y.; Becker, K.G.; Perez, E.; Miller, J.; Hoffer, B.J.; Greig, N.H.; Pick, C.G.

    2012-01-01

    Traumatic brain injury (TBI) is a global problem reaching near epidemic numbers that manifests clinically with cognitive problems that decades later may result in dementias like Alzheimer’s disease (AD). Presently, little can be done to prevent ensuing neurological dysfunctions by pharmacological means. Recently, it has become apparent that several CNS diseases share common terminal features of neuronal cell death. The effects of exendin-4 (Ex-4), a neuroprotective agent delivered via a subcutaneous micro-osmotic pump, were examined in the setting of mild TBI (mTBI). Utilizing a model of mTBI, where cognitive disturbances occur over time, animals were subjected to four treatments: sham; Ex-4; mTBI and Ex-4/mTBI. mTBI mice displayed deficits in novel object recognition, while Ex-4/mTBI mice performed similar to sham. Hippocampal gene expression, assessed by gene array methods, showed significant differences with little overlap in co-regulated genes between groups. Importantly, changes in gene expression induced by mTBI, including genes associated with AD were largely prevented by Ex-4. These data suggest a strong beneficial action of Ex-4 in managing secondary events induced by a traumatic brain injury. PMID:23059457

  19. Beneficial effects of losartan for prevention of paroxysmal atrial fibrillation in patients with sick sinus syndrome: analysis with memory function of pacemaker.

    PubMed

    Takii, Eiichi; Inage, Tomohito; Yoshida, Teruhisa; Ohe, Masatsugu; Gondo, Takeki; Haraguchi, Go; Ito, Shogo; Kumanomido, Jun; Imaizumi, Tsutomu; Fukuomoto, Yoshihiro

    2016-03-01

    Renin-angiotensin system (RAS) inhibitors may be useful in preventing the occurrence of paroxysmal atrial fibrillation (PAF). However, evaluation of such effect is difficult because many PAF episodes are asymptomatic and not all episodes are detected by intermittent electrocardiographic monitoring. A pacemaker has been developed with dedicated functions for AF detection and electrocardiogram storage. Accordingly, we examined the effect of losartan, an angiotensin receptor blocker on PAF occurrence using this new modality. We enrolled 70 consecutive patients who had undergone dual-chamber pacemaker implantation for sick sinus syndrome. Finally, 62 patients participated in the study. Thirty patients were randomized to the losartan group (mean 43 ± 12 mg/day) and 32 patients to the control group. They were followed up for 3 months. The frequency, the maximum duration and the total duration of PAF recorded by the stored electrocardiograms for the last 1 month during the observation period and study period were compared between the two groups. The change in the frequency of PAF from the observation period in the losartan and control groups was similar (-35 ± 25 vs. -67 ± 62 times; NS). However, the change in the maximum duration and the total duration of PAF was significantly shorter in the losartan group than in the control group (-493 ± 158 vs. -10 ± 69 min; p < 0.05, and -4007 ± 2334 vs. 1119 ± 714 min; p < 0.05, respectively). Losartan suppressed the maximum duration and the total duration of PAF in patients with sick sinus syndrome without hemodynamic changes. This is the first study to show the effect of a renin-angiotensin system inhibitor on the secondary prevention of PAF using the dedicated functions of a pacemaker for PAF detection and electrocardiogram storage.

  20. Memory loss

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003257.htm Memory loss To use the sharing features on this ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  1. β-glucan attenuated scopolamine induced cognitive impairment via hippocampal acetylcholinesterase inhibition in rats.

    PubMed

    Haider, Ali; Inam, Wali; Khan, Shahab Ali; Hifza; Mahmood, Wajahat; Abbas, Ghulam

    2016-08-01

    β-glucan (polysaccharide) rich diet has been reported to enhance cognition in humans but the mechanism remained elusive. Keeping this in mind, the present study was designed to investigate the interaction of β-glucan with central cholinergic system. Briefly, in-silico analysis revealed promising interactions of β-glucan with the catalytic residues of acetylcholinesterase (AChE) enzyme. In line with this outcome, the in vitro assay (Ellman's method) also exhibited inhibition of AChE by β-glucan (IC50=0.68±0.08μg/µl). Furthermore, the in vivo study (Morris water maze) showed significant dose dependent reversal of the amnesic effect of scopolamine (2mg/kg i.p.) by β-glucan treatment (5, 25, 50 and 100mg/kg, i.p.). Finally, the hippocampi of aforementioned treated animals also revealed dose dependent inhibition of AChE enzyme. Hence, it can be deduced that β-glucan possesses potential to enhance central cholinergic tone via inhibiting AChE enzyme. In conclusion, the present study provides mechanistic insight to the cognition enhancing potential of β-glucan. Keeping in mind its dietary use and abundance in nature, it can be considered as economic therapeutic option against cognitive ailments associated with decline in cholinergic neurotransmission.

  2. Novel peptide VIP-TAT with higher affinity for PAC1 inhibited scopolamine induced amnesia.

    PubMed

    Yu, Rongjie; Yang, Yanxu; Cui, Zekai; Zheng, Lijun; Zeng, Zhixing; Zhang, Huahua

    2014-10-01

    A novel peptide VIP-TAT with a cell penetrating peptide TAT at the C-terminus of VIP was constructed and prepared using intein mediated purification with an affinity chitin-binding tag (IMPACT) system to enhance the brain uptake efficiency for the medical application in central nervous system. It was found by labeling VIP-TAT and VIP with fluorescein isothiocyanate (FITC) that the extension with TAT increased the brain uptake efficiency of VIP-TAT significantly. Then short-term and long-term treatment with scopolamine (Scop) was used to evaluate the effect of VIP-TAT or VIP on Scop induced amnesia. Both short-term and long-term administration of VIP-TAT inhibited the latent time reduction in step-through test induced by Scop significantly, but long-term administration of VIP aggravated the Scop induced amnesia. Long-term i.p. injection of VIP-TAT was shown to have positive effect by inhibiting the oxidative damage, apoptosis and the cholinergic system activity reduction that induced by Scop, while VIP exerted negative effect in brain opposite to that in periphery system. The in vitro data showed that VIP-TAT had not only protective but also proliferative effect on Neuro2a cells which was inhibited by PAC1 antagonist PACAP(6-38). Competition binding assay and cAMP assay confirmed that VIP-TAT had higher affinity and activation for PAC1 than VIP. So it was concluded that the significantly stronger protective effect of VIP-TAT against Scop induced amnesia than VIP was due to (1) the enhanced brain uptake efficiency of VIP-TAT and (2) the increased affinity and activation of VIP-TAT for receptor PAC1.

  3. Intranasal “painless” Human Nerve Growth Factors Slows Amyloid Neurodegeneration and Prevents Memory Deficits in App X PS1 Mice

    PubMed Central

    Capsoni, Simona; Marinelli, Sara; Ceci, Marcello; Vignone, Domenico; Amato, Gianluca; Malerba, Francesca; Paoletti, Francesca; Meli, Giovanni; Viegi, Alessandro; Pavone, Flaminia; Cattaneo, Antonino

    2012-01-01

    Nerve Growth Factor (NGF) is being considered as a therapeutic candidate for Alzheimer's disease (AD) treatment but the clinical application is hindered by its potent pro-nociceptive activity. Thus, to reduce systemic exposure that would induce pain, in recent clinical studies NGF was administered through an invasive intracerebral gene-therapy approach. Our group demonstrated the feasibility of a non-invasive intranasal delivery of NGF in a mouse model of neurodegeneration. NGF therapeutic window could be further increased if its nociceptive effects could be avoided altogether. In this study we exploit forms of NGF, mutated at residue R100, inspired by the human genetic disease HSAN V (Hereditary Sensory Autonomic Neuropathy Type V), which would allow increasing the dose of NGF without triggering pain. We show that “painless” hNGF displays full neurotrophic and anti-amyloidogenic activities in neuronal cultures, and a reduced nociceptive activity in vivo. When administered intranasally to APPxPS1 mice ( n = 8), hNGFP61S/R100E prevents the progress of neurodegeneration and of behavioral deficits. These results demonstrate the in vivo neuroprotective and anti-amyloidogenic properties of hNGFR100 mutants and provide a rational basis for the development of “painless” hNGF variants as a new generation of therapeutics for neurodegenerative diseases. PMID:22666365

  4. Fear Memory.

    PubMed

    Izquierdo, Ivan; Furini, Cristiane R G; Myskiw, Jociane C

    2016-04-01

    Fear memory is the best-studied form of memory. It was thoroughly investigated in the past 60 years mostly using two classical conditioning procedures (contextual fear conditioning and fear conditioning to a tone) and one instrumental procedure (one-trial inhibitory avoidance). Fear memory is formed in the hippocampus (contextual conditioning and inhibitory avoidance), in the basolateral amygdala (inhibitory avoidance), and in the lateral amygdala (conditioning to a tone). The circuitry involves, in addition, the pre- and infralimbic ventromedial prefrontal cortex, the central amygdala subnuclei, and the dentate gyrus. Fear learning models, notably inhibitory avoidance, have also been very useful for the analysis of the biochemical mechanisms of memory consolidation as a whole. These studies have capitalized on in vitro observations on long-term potentiation and other kinds of plasticity. The effect of a very large number of drugs on fear learning has been intensively studied, often as a prelude to the investigation of effects on anxiety. The extinction of fear learning involves to an extent a reversal of the flow of information in the mentioned structures and is used in the therapy of posttraumatic stress disorder and fear memories in general.

  5. Elder abuse and neglect--"old phenomenon": new directions for research, legislation, and service developments. (2008 Rosalie S. Wolf Memorial Elder Abuse Prevention Award--International Category Lecture).

    PubMed

    Lowenstein, Ariela

    2009-01-01

    This article poses the question: Is elder abuse and neglect a social problem, showing that it is. Elder abuse, though, is still the most hidden form of mistreatment and a key to governmental responses to an ageing population. It is an important facet as a family violence problem, an intergenerational concern, as well as a health, justice and human rights issue. Because the phenomenon of elder abuse and neglect is so complex and multi-dimensional, it has to be addressed by multi-professional and inter-disciplinary approaches. Raising awareness is a fundamental prevention strategy and an important step in causing changes in attitudes and behaviors. This has been accomplished by INPEA and the article was developed from the lecture given by the author on receiving the International Rosalie Wolf Award from INPEA. The discussion focuses on elder abuse as a product of global ageing, stemming from population ageing, which is consistent with an increased prevalence of abuse of all vulnerable groups, older people among them. It is pointed out that baseline and trend data on the nature and prevalence of senior abuse are crucial to policy responses and the development of appropriate programs and services. Difficulties in assessing the scope of the phenomenon, though, are due to: problems in definitions and methodology, which create difficulties in comparing data from various countries; lack of social and familial awareness; isolation of some elders, especially migrants; elder abuse as a 'hidden issue' that usually occurs in the privacy of the home and is viewed as a family affair; limited access to institutional settings. Difficulties also exist in constructing a unifying research framework in order to study the phenomenon due to a lack of comparison groups, a lack of representative national surveys and difficulties in measurement. There is currently, however, an increase in prevalence and incidence studies from both sides of the Atlantic and especially from Europe. But while

  6. Fueling Memories

    PubMed Central

    Powell, Jonathan D.; Pollizzi, Kristen

    2012-01-01

    A hallmark of the adaptive immune response is rapid and robust activation upon rechallenge. In the current issue of Immunity van der Windt et al. (2012) provide an important link between mitochondrial respiratory capacity and the development of CD8+ T cell memory. PMID:22284413

  7. Childhood Memories.

    ERIC Educational Resources Information Center

    Soto, Lourdes Diaz

    2001-01-01

    Describes how artwork can be a valuable catalyst for discussions in preservice education classes, allowing students to explore how their work as educators relates to their childhood memories and can be shaped by childhood experiences. Examines an art exhibition in which diverse artists depicted autobiographical text in their paintings. Discusses…

  8. Retracing Memories

    ERIC Educational Resources Information Center

    Harrison, David L.

    2005-01-01

    There are plenty of paths to poetry but few are as accessible as retracing ones own memories. When students are asked to write about something they remember, they are given them the gift of choosing from events that are important enough to recall. They remember because what happened was funny or scary or embarrassing or heartbreaking or silly.…

  9. Hollow memories

    NASA Astrophysics Data System (ADS)

    2014-04-01

    A hollow-core optical fibre filled with warm caesium atoms can temporarily store the properties of photons. Michael Sprague from the University of Oxford, UK, explains to Nature Photonics how this optical memory could be a useful building block for fibre-based quantum optics.

  10. Involvement of hippocampal Arc in amnesia and its recovery by alcoholic extract of Ashwagandha leaves.

    PubMed

    Gautam, Akash; Wadhwa, Renu; Thakur, Mahendra K

    2013-11-01

    Arc (Activity-regulated cytoskeletal-associated protein) is a member of the immediate-early gene (IEG) family protein. Because of its critical role in learning and memory, it is widely considered to be an important protein in synaptic plasticity and related neurobiological functions. Alcoholic extract of Ashwagandha leaves (i-Extract) was recently shown to have preventive and therapeutic potential for scopolamine-induced amnesia and glutamate-induced excitotoxicity. In the present study, we investigated the involvement of Arc in scopolamine-induced amnesia and its recovery by i-Extract with particular focus to the changes in Arc expression in the hippocampus and cerebral cortex of mice. Morris water maze test showed that spatial learning and memory of mice were drastically reduced by scopolamine administration but improved with i-Extract treatment as compared to control and scopolamine-challenged mice. Molecular analysis revealed a remarkable decline in Arc expression in both hippocampus and cerebral cortex of amnesic mice, which was recovered after i-Extract treatment. Interestingly, Arc expression showed better recovery in the hippocampus than the cerebral cortex and the pre-treatment with i-Extract was more effective than the post-treatment. These findings suggest that Arc may be involved in i-Extract mediated recovery from amnesia.

  11. [Neural correlates of memory].

    PubMed

    Fujii, Toshikatsu

    2013-01-01

    Memory can be divided into several types, although all of them involve three successive processes: encoding, storage, and retrieval. In terms of the duration of retention, neurologists classify memory into immediate, recent, and remote memories, whereas psychologists classify memory into short-term and long-term memories. In terms of the content, episodic, semantic, and procedural memories are considered to be different types of memory. Furthermore, researchers on memory have proposed relatively new concepts of memory, i.e., working memory and prospective memory. This article first provides explanations for these several types of memory. Next, neuropsychological characteristics of amnesic syndrome are briefly outlined. Finally, how several different types of memory are affected (or preserved) in patients with amnesic syndrome is described.

  12. [Will memory be lost with menopause--can an ageing woman be protected from memory disorder?].

    PubMed

    Remes, Anne; Tanila, Heikki; Hallikainen, Merja

    2015-01-01

    Approximately two out of three persons affected with Alzheimer's disease are women. Estrogen is known to have positive effects on the levels of brain-derived mediators and circulation. Along with menopause, decreasing female sex hormone levels have been assumed to promote the development of memory disorders. It is possible that timing of the start of hormone replacement therapy exactly to the menopause could provide the best benefit in respect of memory and information processing. Prevention and treatment of risk factors of cardiovascular diseases along with regular exercise and a healthy diet are more important than hormone therapy in the prevention of memory disorders.

  13. Cell memory-based therapy

    PubMed Central

    Anjamrooz, Seyed Hadi

    2015-01-01

    Current cell therapies, despite all of the progress in this field, still faces major ethical, technical and regulatory hurdles. Because these issues possibly stem from the current, restricted, stereotypical view of cell ultrastructure and function, we must think radically about the nature of the cell. In this regard, the author's theory of the cell memory disc offers ‘memory-based therapy’, which, with the help of immune system rejuvenation, nervous system control and microparticle-based biodrugs, may have substantial therapeutic potential. In addition to its potential value in the study and prevention of premature cell aging, age-related diseases and cell death, memory therapy may improve the treatment of diseases that are currently limited by genetic disorders, risk of tumour formation and the availability and immunocompatibility of tissue transplants. PMID:26256679

  14. Improving Memory Error Handling Using Linux

    SciTech Connect

    Carlton, Michael Andrew; Blanchard, Sean P.; Debardeleben, Nathan A.

    2014-07-25

    As supercomputers continue to get faster and more powerful in the future, they will also have more nodes. If nothing is done, then the amount of memory in supercomputer clusters will soon grow large enough that memory failures will be unmanageable to deal with by manually replacing memory DIMMs. "Improving Memory Error Handling Using Linux" is a process oriented method to solve this problem by using the Linux kernel to disable (offline) faulty memory pages containing bad addresses, preventing them from being used again by a process. The process of offlining memory pages simplifies error handling and results in reducing both hardware and manpower costs required to run Los Alamos National Laboratory (LANL) clusters. This process will be necessary for the future of supercomputing to allow the development of exascale computers. It will not be feasible without memory error handling to manually replace the number of DIMMs that will fail daily on a machine consisting of 32-128 petabytes of memory. Testing reveals the process of offlining memory pages works and is relatively simple to use. As more and more testing is conducted, the entire process will be automated within the high-performance computing (HPC) monitoring software, Zenoss, at LANL.

  15. A Comprehensive Behavioral Test Battery to Assess Learning and Memory in 129S6/Tg2576 Mice

    PubMed Central

    Wolf, Andrea; Bauer, Björn; Abner, Erin L.; Ashkenazy-Frolinger, Tal; Hartz, Anika M. S.

    2016-01-01

    Transgenic Tg2576 mice overexpressing human amyloid precursor protein (hAPP) are a widely used Alzheimer’s disease (AD) mouse model to evaluate treatment effects on amyloid beta (Aβ) pathology and cognition. Tg2576 mice on a B6;SJL background strain carry a recessive rd1 mutation that leads to early retinal degeneration and visual impairment in homozygous carriers. This can impair performance in behavioral tests that rely on visual cues, and thus, affect study results. Therefore, B6;SJL/Tg2576 mice were systematically backcrossed with 129S6/SvEvTac mice resulting in 129S6/Tg2576 mice that lack the rd1 mutation. 129S6/Tg2576 mice do not develop retinal degeneration but still show Aβ accumulation in the brain that is comparable to the original B6;SJL/Tg2576 mouse. However, comprehensive studies on cognitive decline in 129S6/Tg2576 mice are limited. In this study, we used two dementia mouse models on a 129S6 background—scopolamine-treated 129S6/SvEvTac mice (3–5 month-old) and transgenic 129S6/Tg2576 mice (11–13 month-old)–to establish a behavioral test battery for assessing learning and memory. The test battery consisted of five tests to evaluate different aspects of cognitive impairment: a Y-Maze forced alternation task, a novel object recognition test, the Morris water maze, the radial arm water maze, and a Y-maze spontaneous alternation task. We first established this behavioral test battery with the scopolamine-induced dementia model using 129S6/SvEvTac mice and then evaluated 129S6/Tg2576 mice using the same testing protocol. Both models showed distinctive patterns of cognitive impairment. Together, the non-invasive behavioral test battery presented here allows detecting cognitive impairment in scopolamine-treated 129S6/SvEvTac mice and in transgenic 129S6/Tg2576 mice. Due to the modular nature of this test battery, more behavioral tests, e.g. invasive assays to gain additional cognitive information, can easily be added. PMID:26808326

  16. A Beginner's Guide to Memory.

    ERIC Educational Resources Information Center

    Hughes, Elizabeth M.

    1981-01-01

    This article is designed to equip the reader with the information needed to deal with questions of computer memory. Discussed are core memory; semiconductor memory; size of memory; expanding memory; charge-coupled device memories; magnetic bubble memory; and read-only and read-mostly memories. (KC)

  17. SODR Memory Control Buffer Control ASIC

    NASA Technical Reports Server (NTRS)

    Hodson, Robert F.

    1994-01-01

    The Spacecraft Optical Disk Recorder (SODR) is a state of the art mass storage system for future NASA missions requiring high transmission rates and a large capacity storage system. This report covers the design and development of an SODR memory buffer control applications specific integrated circuit (ASIC). The memory buffer control ASIC has two primary functions: (1) buffering data to prevent loss of data during disk access times, (2) converting data formats from a high performance parallel interface format to a small computer systems interface format. Ten 144 p in, 50 MHz CMOS ASIC's were designed, fabricated and tested to implement the memory buffer control function.

  18. The coumarin scopoletin potentiates acetylcholine release from synaptosomes, amplifies hippocampal long-term potentiation and ameliorates anticholinergic- and age-impaired memory

    PubMed Central

    Hornick, A.; Lieb, A.; Vo, N.P.; Rollinger, J.M.; Stuppner, H.; Prast, H.

    2011-01-01

    In a previous study the simple, naturally derived coumarin scopoletin (SCT) was identified as an inhibitor of acetylcholinesterase (AChE), using a pharmacophore-based virtual screening approach. In this study the potential of SCT as procholinergic and cognition-enhancing therapeutic was investigated in a more detailed way, using different experimental approaches like measuring newly synthesized acetylcholine (ACh) in synaptosomes, long-term potentiation (LTP) experiments in hippocampal slices, and behavior studies. SCT enhanced the K+-stimulated release of ACh from rat frontal cortex synaptosomes, showing a bell-shaped dose effect curve (Emax: 4 μM). This effect was blocked by the nicotinic ACh receptor (nAChR) antagonists mecamylamine (MEC) and dihydro-β-erythroidine (DHE). The nAChR agonist (and AChE inhibitor) galantamine induced a similar increase in ACh release (Emax: 1 μM). SCT potentiated LTP in hippocampal slices of rat brain. The high-frequency stimulation (HFS)-induced, N-methyl-D-aspartate (NMDA) receptor dependent LTP of field excitatory postsynaptic potentials at CA3-CA1 synapses was greatly enhanced by pre-HFS application of SCT (4 μM for 4 min). This effect was mimicked by nicotine (2 μM) and abolished by MEC, suggesting an effect on nAChRs. SCT did not restore the total inhibition of LTP by NMDA receptor antagonist d, l-2-amino-5-phosphonopentanoic acid (AP-5). SCT (2 μg, i.c.v.) increased T-maze alternation and ameliorated novel object recognition of mice with scopolamine-induced cholinergic deficit. It also reduced age-associated deficits in object memory of 15–18-month-old mice (2 mg/kg sc). Our findings suggest that SCT possesses memory-improving properties, which are based on its direct nAChR agonistic activity. Therefore, SCT might be able to rescue impaired cholinergic functions by enhancing nAChR-mediated release of neurotransmitters and promoting neural plasticity in hippocampus. PMID:21945033

  19. Memory Retrieval and Interference: Working Memory Issues

    ERIC Educational Resources Information Center

    Radvansky, Gabriel A.; Copeland, David E.

    2006-01-01

    Working memory capacity has been suggested as a factor that is involved in long-term memory retrieval, particularly when that retrieval involves a need to overcome some sort of interference (Bunting, Conway, & Heitz, 2004; Cantor & Engle, 1993). Previous work has suggested that working memory is related to the acquisition of information during…

  20. Optical memory

    DOEpatents

    Mao, Samuel S; Zhang, Yanfeng

    2013-07-02

    Optical memory comprising: a semiconductor wire, a first electrode, a second electrode, a light source, a means for producing a first voltage at the first electrode, a means for producing a second voltage at the second electrode, and a means for determining the presence of an electrical voltage across the first electrode and the second electrode exceeding a predefined voltage. The first voltage, preferably less than 0 volts, different from said second voltage. The semiconductor wire is optically transparent and has a bandgap less than the energy produced by the light source. The light source is optically connected to the semiconductor wire. The first electrode and the second electrode are electrically insulated from each other and said semiconductor wire.

  1. Order-memory and association-memory.

    PubMed

    Caplan, Jeremy B

    2015-09-01

    Two highly studied memory functions are memory for associations (items presented in pairs, such as SALT-PEPPER) and memory for order (a list of items whose order matters, such as a telephone number). Order- and association-memory are at the root of many forms of behaviour, from wayfinding, to language, to remembering people's names. Most researchers have investigated memory for order separately from memory for associations. Exceptions to this, associative-chaining models build an ordered list from associations between pairs of items, quite literally understanding association- and order-memory together. Alternatively, positional-coding models have been used to explain order-memory as a completely distinct function from association-memory. Both classes of model have found empirical support and both have faced serious challenges. I argue that models that combine both associative chaining and positional coding are needed. One such hybrid model, which relies on brain-activity rhythms, is promising, but remains to be tested rigourously. I consider two relatively understudied memory behaviours that demand a combination of order- and association-information: memory for the order of items within associations (is it William James or James William?) and judgments of relative order (who left the party earlier, Hermann or William?). Findings from these underexplored procedures are already difficult to reconcile with existing association-memory and order-memory models. Further work with such intermediate experimental paradigms has the potential to provide powerful findings to constrain and guide models into the future, with the aim of explaining a large range of memory functions, encompassing both association- and order-memory.

  2. Emotional memory persists longer than event memory.

    PubMed

    Kuriyama, Kenichi; Soshi, Takahiro; Fujii, Takeshi; Kim, Yoshiharu

    2010-03-01

    The interaction between amygdala-driven and hippocampus-driven activities is expected to explain why emotion enhances episodic memory recognition. However, overwhelming behavioral evidence regarding the emotion-induced enhancement of immediate and delayed episodic memory recognition has not been obtained in humans. We found that the recognition performance for event memory differs from that for emotional memory. Although event recognition deteriorated equally for episodes that were or were not emotionally salient, emotional recognition remained high for only stimuli related to emotional episodes. Recognition performance pertaining to delayed emotional memory is an accurate predictor of the context of past episodes.

  3. Reducing unwanted trauma memories by imaginal exposure or autobiographical memory elaboration: An analogue study of memory processes

    PubMed Central

    Ehlers, Anke; Mauchnik, Jana; Handley, Rachel

    2012-01-01

    Unwanted memories of traumatic events are a core symptom of post-traumatic stress disorder. A range of interventions including imaginal exposure and elaboration of the trauma memory in its autobiographical context are effective in reducing such unwanted memories. This study explored whether priming for stimuli that occur in the context of trauma and evaluative conditioning may play a role in the therapeutic effects of these procedures. Healthy volunteers (N = 122) watched analogue traumatic and neutral picture stories. They were then randomly allocated to 20 min of either imaginal exposure, autobiographical memory elaboration, or a control condition designed to prevent further processing of the picture stories. A blurred picture identification task showed that neutral objects that preceded traumatic pictures in the stories were subsequently more readily identified than those that had preceded neutral stories, indicating enhanced priming. There was also an evaluative conditioning effect in that participants disliked neutral objects that had preceded traumatic pictures more. Autobiographical memory elaboration reduced the enhanced priming effect. Both interventions reduced the evaluative conditioning effect. Imaginal exposure and autobiographical memory elaboration both reduced the frequency of subsequent unwanted memories of the picture stories. PMID:21227404

  4. Rape prevention

    MedlinePlus

    Date rape - prevention; Sexual assault - prevention ... Centers for Disease Control and Prevention. Sexual assault and abuse and STDs. In: 2015 sexually transmitted diseases treatment guidelines 2015. Updated June 4, 2015. www.cdc.gov/ ...

  5. Memory beyond expression.

    PubMed

    Delorenzi, A; Maza, F J; Suárez, L D; Barreiro, K; Molina, V A; Stehberg, J

    2014-01-01

    The idea that memories are not invariable after the consolidation process has led to new perspectives about several mnemonic processes. In this framework, we review our studies on the modulation of memory expression during reconsolidation. We propose that during both memory consolidation and reconsolidation, neuromodulators can determine the probability of the memory trace to guide behavior, i.e. they can either increase or decrease its behavioral expressibility without affecting the potential of persistent memories to be activated and become labile. Our hypothesis is based on the findings that positive modulation of memory expression during reconsolidation occurs even if memories are behaviorally unexpressed. This review discusses the original approach taken in the studies of the crab Neohelice (Chasmagnathus) granulata, which was then successfully applied to test the hypothesis in rodent fear memory. Data presented offers a new way of thinking about both weak trainings and experimental amnesia: memory retrieval can be dissociated from memory expression. Furthermore, the strategy presented here allowed us to show in human declarative memory that the periods in which long-term memory can be activated and become labile during reconsolidation exceeds the periods in which that memory is expressed, providing direct evidence that conscious access to memory is not needed for reconsolidation. Specific controls based on the constraints of reminders to trigger reconsolidation allow us to distinguish between obliterated and unexpressed but activated long-term memories after amnesic treatments, weak trainings and forgetting. In the hypothesis discussed, memory expressibility--the outcome of experience-dependent changes in the potential to behave--is considered as a flexible and modulable attribute of long-term memories. Expression seems to be just one of the possible fates of re-activated memories.

  6. Covalent modification of DNA regulates memory formation.

    PubMed

    Miller, Courtney A; Sweatt, J David

    2007-03-15

    DNA methylation is a covalent chemical modification of DNA catalyzed by DNA methyltransferases (DNMTs). DNA methylation is associated with transcriptional silencing and has been studied extensively as a lifelong molecular information storage mechanism put in place during development. Here we report that DNMT gene expression is upregulated in the adult rat hippocampus following contextual fear conditioning and that DNMT inhibition blocks memory formation. In addition, fear conditioning is associated with rapid methylation and transcriptional silencing of the memory suppressor gene PP1 and demethylation and transcriptional activation of the synaptic plasticity gene reelin, indicating both methyltransferase and demethylase activity during consolidation. DNMT inhibition prevents the PP1 methylation increase, resulting in aberrant transcription of the gene during the memory-consolidation period. These results demonstrate that DNA methylation is dynamically regulated in the adult nervous system and that this cellular mechanism is a crucial step in memory formation.

  7. Retrieval Is Not Necessary to Trigger Reconsolidation of Object Recognition Memory in the Perirhinal Cortex

    ERIC Educational Resources Information Center

    Santoyo-Zedillo, Marianela; Rodriguez-Ortiz, Carlos J.; Chavez-Marchetta, Gianfranco; Bermudez-Rattoni, Federico; Balderas, Israela

    2014-01-01

    Memory retrieval has been considered as requisite to initiate memory reconsolidation; however, some studies indicate that blocking retrieval does not prevent memory from undergoing reconsolidation. Since N-methyl-D-aspartate (NMDA) and a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors in the perirhinal cortex have…

  8. Bayesian Analysis of Recognition Memory: The Case of the List-Length Effect

    ERIC Educational Resources Information Center

    Dennis, Simon; Lee, Michael D.; Kinnell, Angela

    2008-01-01

    Recognition memory experiments are an important source of empirical constraints for theories of memory. Unfortunately, standard methods for analyzing recognition memory data have problems that are often severe enough to prevent clear answers being obtained. A key example is whether longer lists lead to poorer recognition performance. The presence…

  9. Benzodiazepines and memory

    PubMed Central

    Roth, T.; Roehrs, T.; Wittig, R.; Zorick, F.

    1984-01-01

    1 Benzodiazepines possess anterograde amnesic properties, disrupting both short-term and long-term memory function. 2 The amount of amnesia is systematically related to dose effects and half-life differences among the benzodiazepines. 3 Memory deficits are found for episodic, semantic, and iconic memory function. 4 The deficits in long-term memory are probably the result of a disruption of consolidation of information in memory and not retrieval from memory. The disruption is produced by rapid sleep onset. 5 Thus the long-term amnesia is really a retrograde effect of sleep and not the anterograde effect of the drug. PMID:6151849

  10. Problems of neural memory

    NASA Astrophysics Data System (ADS)

    Mikaelian, Andrei L.

    2005-01-01

    The paper considers the neural memory of the human brain from the viewpoint of visual information processing. A model that explains the principle of data recording and storing, memory relaxation, associative remembering and other memory functions is offered. The model of associative memory is based on the methods of holography, "wave biochemistry" and autowaves. Brief consideration is given to the associative properties of holographic neural structures and the memory architecture using running chemical reactions. The paper also outlines the problem of developing artificial memory elements for restoring the brain functions and possible interface devices for coupling neurons to electronic systems.

  11. Searching for repressed memory.

    PubMed

    McNally, Richard J

    2012-01-01

    This chapter summarizes the work of my research group on adults who report either repressed, recovered, or continuous memories of childhood sexual abuse (CSA) or who report no history of CSA. Adapting paradigms from cognitive psychology, we tested hypotheses inspired by both the "repressed memory" and "false memory" perspectives on recovered memories of CSA. We found some evidence for the false memory perspective, but no evidence for the repressed memory perspective. However, our work also suggests a third perspective on recovered memories that does not require the concept of repression. Some children do not understand their CSA when it occurs, and do not experience terror. Years later, they recall the experience, and understanding it as abuse, suffer intense distress. The memory failed to come to mind for years, partly because the child did not encode it as terrifying (i.e., traumatic), not because the person was unable to recall it.

  12. Emotional Memory Persists Longer than Event Memory

    ERIC Educational Resources Information Center

    Kuriyama, Kenichi; Soshi, Takahiro; Fujii, Takeshi; Kim, Yoshiharu

    2010-01-01

    The interaction between amygdala-driven and hippocampus-driven activities is expected to explain why emotion enhances episodic memory recognition. However, overwhelming behavioral evidence regarding the emotion-induced enhancement of immediate and delayed episodic memory recognition has not been obtained in humans. We found that the recognition…

  13. Memory and the Self

    ERIC Educational Resources Information Center

    Conway, Martin A.

    2005-01-01

    The Self-Memory System (SMS) is a conceptual framework that emphasizes the interconnectedness of self and memory. Within this framework memory is viewed as the data base of the self. The self is conceived as a complex set of active goals and associated self-images, collectively referred to as the "working self." The relationship between the…

  14. Music, memory and emotion.

    PubMed

    Jäncke, Lutz

    2008-08-08

    Because emotions enhance memory processes and music evokes strong emotions, music could be involved in forming memories, either about pieces of music or about episodes and information associated with particular music. A recent study in BMC Neuroscience has given new insights into the role of emotion in musical memory.

  15. Dynamic learning and memory, synaptic plasticity and neurogenesis: an update

    PubMed Central

    Stuchlik, Ales

    2014-01-01

    Mammalian memory is the result of the interaction of millions of neurons in the brain and their coordinated activity. Candidate mechanisms for memory are synaptic plasticity changes, such as long-term potentiation (LTP). LTP is essentially an electrophysiological phenomenon manifested in hours-lasting increase on postsynaptic potentials after synapse tetanization. It is thought to ensure long-term changes in synaptic efficacy in distributed networks, leading to persistent changes in the behavioral patterns, actions and choices, which are often interpreted as the retention of information, i.e., memory. Interestingly, new neurons are born in the mammalian brain and adult hippocampal neurogenesis is proposed to provide a substrate for dynamic and flexible aspects of behavior such as pattern separation, prevention of interference, flexibility of behavior and memory resolution. This work provides a brief review on the memory and involvement of LTP and adult neurogenesis in memory phenomena. PMID:24744707

  16. Immunological memory is associative

    SciTech Connect

    Smith, D.J.; Forrest, S.; Perelson, A.S.

    1996-12-31

    The purpose of this paper is to show that immunological memory is an associative and robust memory that belongs to the class of sparse distributed memories. This class of memories derives its associative and robust nature by sparsely sampling the input space and distributing the data among many independent agents. Other members of this class include a model of the cerebellar cortex and Sparse Distributed Memory (SDM). First we present a simplified account of the immune response and immunological memory. Next we present SDM, and then we show the correlations between immunological memory and SDM. Finally, we show how associative recall in the immune response can be both beneficial and detrimental to the fitness of an individual.

  17. Flexible Kernel Memory

    PubMed Central

    Nowicki, Dimitri; Siegelmann, Hava

    2010-01-01

    This paper introduces a new model of associative memory, capable of both binary and continuous-valued inputs. Based on kernel theory, the memory model is on one hand a generalization of Radial Basis Function networks and, on the other, is in feature space, analogous to a Hopfield network. Attractors can be added, deleted, and updated on-line simply, without harming existing memories, and the number of attractors is independent of input dimension. Input vectors do not have to adhere to a fixed or bounded dimensionality; they can increase and decrease it without relearning previous memories. A memory consolidation process enables the network to generalize concepts and form clusters of input data, which outperforms many unsupervised clustering techniques; this process is demonstrated on handwritten digits from MNIST. Another process, reminiscent of memory reconsolidation is introduced, in which existing memories are refreshed and tuned with new inputs; this process is demonstrated on series of morphed faces. PMID:20552013

  18. Memory access in shared virtual memory

    SciTech Connect

    Berrendorf, R. )

    1992-01-01

    Shared virtual memory (SVM) is a virtual memory layer with a single address space on top of a distributed real memory on parallel computers. We examine the behavior and performance of SVM running a parallel program with medium-grained, loop-level parallelism on top of it. A simulator for the underlying parallel architecture can be used to examine the behavior of SVM more deeply. The influence of several parameters, such as the number of processors, page size, cold or warm start, and restricted page replication, is studied.

  19. Memory access in shared virtual memory

    SciTech Connect

    Berrendorf, R.

    1992-09-01

    Shared virtual memory (SVM) is a virtual memory layer with a single address space on top of a distributed real memory on parallel computers. We examine the behavior and performance of SVM running a parallel program with medium-grained, loop-level parallelism on top of it. A simulator for the underlying parallel architecture can be used to examine the behavior of SVM more deeply. The influence of several parameters, such as the number of processors, page size, cold or warm start, and restricted page replication, is studied.

  20. Stochastic memory: memory enhancement due to noise.

    PubMed

    Stotland, Alexander; Di Ventra, Massimiliano

    2012-01-01

    There are certain classes of resistors, capacitors, and inductors that, when subject to a periodic input of appropriate frequency, develop hysteresis loops in their characteristic response. Here we show that the hysteresis of such memory elements can also be induced by white noise of appropriate intensity even at very low frequencies of the external driving field. We illustrate this phenomenon using a physical model of memory resistor realized by TiO(2) thin films sandwiched between metallic electrodes and discuss under which conditions this effect can be observed experimentally. We also discuss its implications on existing memory systems described in the literature and the role of colored noise.

  1. Stochastic memory: Memory enhancement due to noise

    NASA Astrophysics Data System (ADS)

    Stotland, Alexander; di Ventra, Massimiliano

    2012-01-01

    There are certain classes of resistors, capacitors, and inductors that, when subject to a periodic input of appropriate frequency, develop hysteresis loops in their characteristic response. Here we show that the hysteresis of such memory elements can also be induced by white noise of appropriate intensity even at very low frequencies of the external driving field. We illustrate this phenomenon using a physical model of memory resistor realized by TiO2 thin films sandwiched between metallic electrodes and discuss under which conditions this effect can be observed experimentally. We also discuss its implications on existing memory systems described in the literature and the role of colored noise.

  2. The Role of Actin Cytoskeleton in Memory Formation in Amygdala

    PubMed Central

    Lamprecht, Raphael

    2016-01-01

    The central, lateral and basolateral amygdala (BLA) nuclei are essential for the formation of long-term memories including emotional and drug-related memories. Studying cellular and molecular mechanisms of memory in amygdala may lead to better understanding of how memory is formed and of fear and addiction-related disorders. A challenge is to identify molecules activated by learning that subserve cellular changes needed for memory formation and maintenance in amygdala. Recent studies show that activation of synaptic receptors during fear and drug-related learning leads to alteration in actin cytoskeleton dynamics and structure in amygdala. Such changes in actin cytoskeleton in amygdala are essential for fear and drug-related memories formation. Moreover, the actin cytoskeleton subserves, after learning, changes in neuronal morphogenesis and glutamate receptors trafficking in amygdala. These cellular events are involved in fear and drug-related memories formation. Actin polymerization is also needed for the maintenance of drug-associated memories in amygdala. Thus, the actin cytoskeleton is a key mediator between receptor activation during learning and cellular changes subserving long-term memory (LTM) in amygdala. The actin cytoskeleton may serve as a target for pharmacological treatment of fear memory associated with fear and anxiety disorders and drug addiction to prevent the debilitating consequences of these diseases. PMID:27065800

  3. Poison Prevention

    MedlinePlus

    ... the Word Shop AAP Find a Pediatrician Safety & Prevention Immunizations All Around At Home At Play On ... Listen Español Text Size Email Print Share Poison Prevention Page Content Article Body Post the Poison Help ...

  4. Memory bistable mechanisms of organic memory devices

    NASA Astrophysics Data System (ADS)

    Lee, Ching-Ting; Yu, Li-Zhen; Chen, Hung-Chun

    2010-07-01

    To investigate the memory bistable mechanisms of organic memory devices, the structure of [top Au anode/9,10-di(2-naphthyl)anthracene (ADN) active layer/bottom Au cathode] was deposited using a thermal deposition system. The Au atoms migrated into the ADN active layer was observed from the secondary ion mass spectrometry. The density of 9.6×1016 cm-3 and energy level of 0.553 eV of the induced trapping centers caused by the migrated Au atoms in the ADN active layer were calculated. The induced trapping centers did not influence the carrier injection barrier height between Au and ADN active layer. Therefore, the memory bistable behaviors of the organic memory devices were attributed to the induced trapping centers. The energy diagram was established to verify the mechanisms.

  5. Vitamin C deficiency increases basal exploratory activity but decreases scopolamine-induced activity in APP/PSEN1 transgenic mice

    PubMed Central

    Harrison, F. E.; May, J. M.; McDonald, M. P.

    2010-01-01

    Vitamin C is a powerful antioxidant and its levels are decreased in Alzheimer's patients. Even sub-clinical vitamin C deficiency could impact disease development. To investigate this principle we crossed APP/PSEN1 transgenic mice with Gulo knockout mice unable to synthesize their own vitamin C. Experimental mice were maintained from 6 weeks of age on standard (0.33 g/L) or reduced (0.099 g/L) levels of vitamin C and then assessed for changes in behavior and neuropathology. APP/PSEN1 mice showed impaired spatial learning in the Barnes maze and water maze that was not further impacted by vitamin C level. However, long-term decreased vitamin C levels led to hyperactivity in transgenic mice, with altered locomotor habituation and increased omission errors in the Barnes maze. Decreased vitamin C also led to increased oxidative stress. Transgenic mice were more susceptible to the activity-enhancing effects of scopolamine and low vitamin C attenuated these effects in both genotypes. These data indicate an interaction between the cholinergic system and vitamin C that could be important given the cholinergic degeneration associated with Alzheimer's disease. PMID:19941887

  6. Psychophysiology of prospective memory.

    PubMed

    Rothen, Nicolas; Meier, Beat

    2014-01-01

    Prospective memory involves the self-initiated retrieval of an intention upon an appropriate retrieval cue. Cue identification can be considered as an orienting reaction and may thus trigger a psychophysiological response. Here we present two experiments in which skin conductance responses (SCRs) elicited by prospective memory cues were compared to SCRs elicited by aversive stimuli to test whether a single prospective memory cue triggers a similar SCR as an aversive stimulus. In Experiment 2 we also assessed whether cue specificity had a differential influence on prospective memory performance and on SCRs. We found that detecting a single prospective memory cue is as likely to elicit a SCR as an aversive stimulus. Missed prospective memory cues also elicited SCRs. On a behavioural level, specific intentions led to better prospective memory performance. However, on a psychophysiological level specificity had no influence. More generally, the results indicate reliable SCRs for prospective memory cues and point to psychophysiological measures as valuable approach, which offers a new way to study one-off prospective memory tasks. Moreover, the findings are consistent with a theory that posits multiple prospective memory retrieval stages.

  7. Medicinal Herbs in Iranian Traditional Medicine for Learning and Memory

    PubMed Central

    Shojaii, Asie; Ghods, Roshanak; Fard, Mehri Abdollahi

    2016-01-01

    Background: A few factors such as age, stress, and emotions may lead to impaired learning, memory loss, amnesia, and dementia or threats like schizophrenia and Alzheimer’s disease (AD). Iranian traditional medicine (ITM) recommends some herbs and herbal preparations for the treatment or prevention of CNS problems. Methods: In this study, scientific evidence related to the effectiveness of ITM herbal medicine on memory, learning and AD is reviewed. The scientific evidence of plant efficacy was searched in electronic databases including PubMed, Scopus, SID, Science Direct, and Google Scholar by keywords such as memory, Alzheimer, amnesia, learning and scientific plant names from 1969 to 2014. Results: The findings of this study confirmed the effectiveness of certain ITM medicinal plants on enhancing memory and learning or in the treatment/prevention of amnesia and AD. Some ITM plants like Melissa officinalis, Crocus sativus and Nigella sativa showed improving effects on memory and the treatment of AD in clinical trials. In some cases, active principles responsible for the efficacy of these plants on memory were also determined. Discussion: Most of the studies on ITM plants were designed in animal models and a few herbs were evaluated in clinical trials on AD. Furthermore, there are insufficient or no investigations on certain herbal medicines used in ITM to confirm their effectiveness on memory and learning. Therefore, further experimental and clinical studies are necessary to evaluate the effectiveness of these plants on memory and AD as well as determining their active components. PMID:27516676

  8. Medicinal Herbs in Iranian Traditional Medicine for Learning and Memory

    PubMed Central

    Shojaii, Asie; Ghods, Roshanak; Fard, Mehri Abdollahi

    2016-01-01

    Background: A few factors such as age, stress, and emotions may lead to impaired learning, memory loss, amnesia, and dementia or threats like schizophrenia and Alzheimer’s disease (AD). Iranian traditional medicine (ITM) recommends some herbs and herbal preparations for the treatment or prevention of CNS problems. Methods: In this study, scientific evidence related to the effectiveness of ITM herbal medicine on memory, learning and AD is reviewed. The scientific evidence of plant efficacy was searched in electronic databases including PubMed, Scopus, SID, Science Direct, and Google Scholar by keywords such as memory, Alzheimer, amnesia, learning and scientific plant names from 1969 to 2014. Results: The findings of this study confirmed the effectiveness of certain ITM medicinal plants on enhancing memory and learning or in the treatment/prevention of amnesia and AD. Some ITM plants like Melissa officinalis, Crocus sativus and Nigella sativa showed improving effects on memory and the treatment of AD in clinical trials. In some cases, active principles responsible for the efficacy of these plants on memory were also determined. Discussion: Most of the studies on ITM plants were designed in animal models and a few herbs were evaluated in clinical trials on AD. Furthermore, there are insufficient or no investigations on certain herbal medicines used in ITM to confirm their effectiveness on memory and learning. Therefore, further experimental and clinical studies are necessary to evaluate the effectiveness of these plants on memory and AD as well as determining their active components. PMID:27840509

  9. Human learning and memory.

    PubMed

    Johnson, M K; Hasher, L

    1987-01-01

    There have been several notable recent trends in the area of learning and memory. Problems with the episodic/semantic distinction have become more apparent, and new efforts have been made (exemplar models, distributed-memory models) to represent general knowledge without assuming a separate semantic system. Less emphasis is being placed on stable, prestored prototypes and more emphasis on a flexible memory system that provides the basis for a multitude of categories or frames of reference, derived on the spot as tasks demand. There is increasing acceptance of the idea that mental models are constructed and stored in memory in addition to, rather than instead of, memorial representations that are more closely tied to perceptions. This gives rise to questions concerning the conditions that permit inferences to be drawn and mental models to be constructed, and to questions concerning the similarities and differences in the nature of the representations in memory of perceived and generated information and in their functions. There has also been a swing from interest in deliberate strategies to interest in automatic, unconscious (even mechanistic!) processes, reflecting an appreciation that certain situations (e.g. recognition, frequency judgements, savings in indirect tasks, aspects of skill acquisition, etc) seem not to depend much on the products of strategic, effortful or reflective processes. There is a lively interest in relations among memory measures and attempts to characterize memory representations and/or processes that could give rise to dissociations among measures. Whether the pattern of results reflects the operation of functional subsystems of memory and, if so, what the "modules" are is far from clear. This issue has been fueled by work with amnesics and has contributed to a revival of interaction between researchers studying learning and memory in humans and those studying learning and memory in animals. Thus, neuroscience rivals computer science as a

  10. Conscious and Unconscious Memory Systems

    PubMed Central

    Squire, Larry R.; Dede, Adam J.O.

    2015-01-01

    The idea that memory is not a single mental faculty has a long and interesting history but became a topic of experimental and biologic inquiry only in the mid-20th century. It is now clear that there are different kinds of memory, which are supported by different brain systems. One major distinction can be drawn between working memory and long-term memory. Long-term memory can be separated into declarative (explicit) memory and a collection of nondeclarative (implicit) forms of memory that include habits, skills, priming, and simple forms of conditioning. These memory systems depend variously on the hippocampus and related structures in the parahippocampal gyrus, as well as on the amygdala, the striatum, cerebellum, and the neocortex. This work recounts the discovery of declarative and nondeclarative memory and then describes the nature of declarative memory, working memory, nondeclarative memory, and the relationship between memory systems. PMID:25731765

  11. A generalized memory test algorithm

    NASA Technical Reports Server (NTRS)

    Milner, E. J.

    1982-01-01

    A general algorithm for testing digital computer memory is presented. The test checks that (1) every bit can be cleared and set in each memory work, and (2) bits are not erroneously cleared and/or set elsewhere in memory at the same time. The algorithm can be applied to any size memory block and any size memory word. It is concise and efficient, requiring the very few cycles through memory. For example, a test of 16-bit-word-size memory requries only 384 cycles through memory. Approximately 15 seconds were required to test a 32K block of such memory, using a microcomputer having a cycle time of 133 nanoseconds.

  12. Regulatory T cell memory

    PubMed Central

    Rosenblum, Michael D.; Way, Sing Sing; Abbas, Abul K.

    2016-01-01

    Memory for antigen is a defining feature of adaptive immunity. Antigen-specific lymphocyte populations show an increase in number and function after antigen encounter and more rapidly re-expand upon subsequent antigen exposure. Studies of immune memory have primarily focused on effector B cells and T cells with microbial specificity, using prime challenge models of infection. However, recent work has also identified persistently expanded populations of antigen-specific regulatory T cells that protect against aberrant immune responses. In this Review, we consider the parallels between memory effector T cells and memory regulatory T cells, along with the functional implications of regulatory memory in autoimmunity, antimicrobial host defence and maternal fetal tolerance. In addition, we discuss emerging evidence for regulatory T cell memory in humans and key unanswered questions in this rapidly evolving field. PMID:26688349

  13. Shape memory polymers

    DOEpatents

    Wilson, Thomas S.; Bearinger, Jane P.

    2015-06-09

    New shape memory polymer compositions, methods for synthesizing new shape memory polymers, and apparatus comprising an actuator and a shape memory polymer wherein the shape memory polymer comprises at least a portion of the actuator. A shape memory polymer comprising a polymer composition which physically forms a network structure wherein the polymer composition has shape-memory behavior and can be formed into a permanent primary shape, re-formed into a stable secondary shape, and controllably actuated to recover the permanent primary shape. Polymers have optimal aliphatic network structures due to minimization of dangling chains by using monomers that are symmetrical and that have matching amine and hydroxyl groups providing polymers and polymer foams with clarity, tight (narrow temperature range) single transitions, and high shape recovery and recovery force that are especially useful for implanting in the human body.

  14. Content Addressable Memory Project

    DTIC Science & Technology

    1990-11-01

    The Content Addressable M1-emory Project consists of the development of several experimental software systems on an AMT Distributed Array Processor...searching (database) compiler algorithms memory management other systems software) Linear C is an unlovely hybrid language which imports the CAM...memory from AMT’s operating system for the DAP; how- ever, other than this limitation, the memory management routines work exactly as their C counterparts

  15. Sparse distributed memory

    NASA Technical Reports Server (NTRS)

    Kanerva, Pentti

    1988-01-01

    Theoretical models of the human brain and proposed neural-network computers are developed analytically. Chapters are devoted to the mathematical foundations, background material from computer science, the theory of idealized neurons, neurons as address decoders, and the search of memory for the best match. Consideration is given to sparse memory, distributed storage, the storage and retrieval of sequences, the construction of distributed memory, and the organization of an autonomous learning system.

  16. Memory Load and Dump

    NASA Astrophysics Data System (ADS)

    Welty, Alan

    2009-07-01

    This proposal is a test and verification of the STIS dump of memory capability.Areas of Control Section {CS} to dump include: EDAC RAM, EEPROM, and CS PROM {with the CS in Operate}. Areas of MIE memory to dump include: MIE RAM and MIE PROM {with the MIE in Operate}. Note that the MIE memory must first be copied to CS buffer RAM as images, which are then dumped.Supports Activity STIS-02

  17. Myrmics Memory Allocator

    SciTech Connect

    Lymperis, S.

    2011-09-23

    MMA is a stand-alone memory management system for MPI clusters. It implements a shared Partitioned Global Address Space, where multiple MPI processes request objects from the allocator and the latter provides them with system-wide unique memory addresses for each object. It provides applications with an intuitive way of managing the memory system in a unified way, thus enabling easier writing of irregular application code.

  18. Memory Golf Clubs

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Memory Corporation's investigation of shape memory effect, stemming from Marshall Space Flight Center contracts to study materials for the space station, has aided in the development of Zeemet, a proprietary, high-damping shape memory alloy for the golf industry. The Nicklaus Golf Company has created a new line of golf clubs using Zeemet inserts. Its superelastic and high damping attributes translate into more spin on the ball, greater control, and a solid feel.

  19. Networks of Memories

    DTIC Science & Technology

    2013-03-01

    2000). The construction of  autobiographical   memories in the self­memory system. Psychological Review, 107(2), 261­288. Dennis, S., & Chapman, A. (2010...AFRL-OSR-VA-TR-2013-0131 Networks of Memories Simon Dennis, Mikhail Belkin Ohio State University March 2013 Final...Back (Rev. 8/98) 1 Networks of  Memories FA9550­09­1­0614 Professor Jay Myung PI: Simon Dennis Ohio State University February 15, 2013 2 Introduction

  20. Hypnosis, memory and amnesia.

    PubMed Central

    Kihlstrom, J F

    1997-01-01

    Hypnotized subjects respond to suggestions from the hypnotist for imaginative experiences involving alterations in perception and memory. Individual differences in hypnotizability are only weakly related to other forms of suggestibility. Neuropsychological speculations about hypnosis focus on the right hemisphere and/or the frontal lobes. Posthypnotic amnesia refers to subjects' difficulty in remembering, after hypnosis, the events and experiences that transpired while they were hypnotized. Posthypnotic amnesia is not an instance of state-dependent memory, but it does seem to involve a disruption of retrieval processes similar to the functional amnesias observed in clinical dissociative disorders. Implicit memory, however, is largely spared, and may underlie subjects' ability to recognize events that they cannot recall. Hypnotic hypermnesia refers to improved memory for past events. However, such improvements are illusory: hypermnesia suggestions increase false recollection, as well as subjects' confidence in both true and false memories. Hypnotic age regression can be subjectively compelling, but does not involve the ablation of adult memory, or the reinstatement of childlike modes of mental functioning, or the revivification of memory. The clinical and forensic use of hypermnesia and age regression to enhance memory in patients, victims and witnesses (e.g. recovered memory therapy for child sexual abuse) should be discouraged. PMID:9415925

  1. New gravitational memories

    NASA Astrophysics Data System (ADS)

    Pasterski, Sabrina; Strominger, Andrew; Zhiboedov, Alexander

    2016-12-01

    The conventional gravitational memory effect is a relative displacement in the position of two detectors induced by radiative energy flux. We find a new type of gravitational `spin memory' in which beams on clockwise and counterclockwise orbits acquire a relative delay induced by radiative angular momentum flux. It has recently been shown that the displacement memory formula is a Fourier transform in time of Weinberg's soft graviton theorem. Here we see that the spin memory formula is a Fourier transform in time of the recently-discovered subleading soft graviton theorem.

  2. Sparse distributed memory overview

    NASA Technical Reports Server (NTRS)

    Raugh, Mike

    1990-01-01

    The Sparse Distributed Memory (SDM) project is investigating the theory and applications of massively parallel computing architecture, called sparse distributed memory, that will support the storage and retrieval of sensory and motor patterns characteristic of autonomous systems. The immediate objectives of the project are centered in studies of the memory itself and in the use of the memory to solve problems in speech, vision, and robotics. Investigation of methods for encoding sensory data is an important part of the research. Examples of NASA missions that may benefit from this work are Space Station, planetary rovers, and solar exploration. Sparse distributed memory offers promising technology for systems that must learn through experience and be capable of adapting to new circumstances, and for operating any large complex system requiring automatic monitoring and control. Sparse distributed memory is a massively parallel architecture motivated by efforts to understand how the human brain works. Sparse distributed memory is an associative memory, able to retrieve information from cues that only partially match patterns stored in the memory. It is able to store long temporal sequences derived from the behavior of a complex system, such as progressive records of the system's sensory data and correlated records of the system's motor controls.

  3. The future of memory

    NASA Astrophysics Data System (ADS)

    Marinella, M.

    In the not too distant future, the traditional memory and storage hierarchy of may be replaced by a single Storage Class Memory (SCM) device integrated on or near the logic processor. Traditional magnetic hard drives, NAND flash, DRAM, and higher level caches (L2 and up) will be replaced with a single high performance memory device. The Storage Class Memory paradigm will require high speed (< 100 ns read/write), excellent endurance (> 1012), nonvolatility (retention > 10 years), and low switching energies (< 10 pJ per switch). The International Technology Roadmap for Semiconductors (ITRS) has recently evaluated several potential candidates SCM technologies, including Resistive (or Redox) RAM, Spin Torque Transfer RAM (STT-MRAM), and phase change memory (PCM). All of these devices show potential well beyond that of current flash technologies and research efforts are underway to improve the endurance, write speeds, and scalabilities to be on-par with DRAM. This progress has interesting implications for space electronics: each of these emerging device technologies show excellent resistance to the types of radiation typically found in space applications. Commercially developed, high density storage class memory-based systems may include a memory that is physically radiation hard, and suitable for space applications without major shielding efforts. This paper reviews the Storage Class Memory concept, emerging memory devices, and possible applicability to radiation hardened electronics for space.

  4. [Memory disorders in schizophrenia].

    PubMed

    Danion, J M; Peretti, S; Gras-Vincendon, A; Singer, L

    1992-01-01

    The current interest in memory disorders in schizophrenia results from the way perceptions of schizophrenia--whose organic origin is becoming increasingly evident--and memory--according to which there exist not one, but several memories--have developed. Memory disorders in the schizophrenic cannot be considered in isolation from knowledge accumulated in other areas of the cognitive and neuro-sciences; a more detailed understanding of these disorders requires a comparison of the different cognitive approaches, both with each other and with the neurobiological and clinical approaches, so that they can be integrated. Despite numerous methodological and conceptual difficulties, it now appears to have been established that the schizophrenic's memory deficit should be seen in the context of a wider cognitive deficit, that the memory tasks are not all disturbed and that the memory deficit cannot be identified with one specific form of memory. Thus, iconic formation, short-term memory in the traditionally accepted sense and implicit memory are hardly, if at all, affected; in contrast, the early processing of information, working memory and explicit memory are disturbed, probably to the extent that they require the implementation of strategies to organise the information to be memorized. Finally, in certain tasks, such as those evaluating latent inhibition or negative priming, schizophrenics perform better than normal subjects, suggesting that schizophrenics' cognitive deficit is localised. This profile of memory disorders is compatible with a dysfunction predominating in the frontal and temporo-hippocampal regions. Neuroleptics and anticholinergics have opposite effects on cognitive and mnesic performance, which is improved by the former and aggravated by the latter. The influence of clinical symptoms, positive or negative, institutionalisation of patients and chronic tardive dyskinesia is unclear. Among the theoretical proposals put forward to account for the observed

  5. A cannabinoid link between mitochondria and memory.

    PubMed

    Hebert-Chatelain, Etienne; Desprez, Tifany; Serrat, Román; Bellocchio, Luigi; Soria-Gomez, Edgar; Busquets-Garcia, Arnau; Pagano Zottola, Antonio Christian; Delamarre, Anna; Cannich, Astrid; Vincent, Peggy; Varilh, Marjorie; Robin, Laurie M; Terral, Geoffrey; García-Fernández, M Dolores; Colavita, Michelangelo; Mazier, Wilfrid; Drago, Filippo; Puente, Nagore; Reguero, Leire; Elezgarai, Izaskun; Dupuy, Jean-William; Cota, Daniela; Lopez-Rodriguez, Maria-Luz; Barreda-Gómez, Gabriel; Massa, Federico; Grandes, Pedro; Bénard, Giovanni; Marsicano, Giovanni

    2016-11-24

    Cellular activity in the brain depends on the high energetic support provided by mitochondria, the cell organelles which use energy sources to generate ATP. Acute cannabinoid intoxication induces amnesia in humans and animals, and the activation of type-1 cannabinoid receptors present at brain mitochondria membranes (mtCB1) can directly alter mitochondrial energetic activity. Although the pathological impact of chronic mitochondrial dysfunctions in the brain is well established, the involvement of acute modulation of mitochondrial activity in high brain functions, including learning and memory, is unknown. Here, we show that acute cannabinoid-induced memory impairment in mice requires activation of hippocampal mtCB1 receptors. Genetic exclusion of CB1 receptors from hippocampal mitochondria prevents cannabinoid-induced reduction of mitochondrial mobility, synaptic transmission and memory formation. mtCB1 receptors signal through intra-mitochondrial Gαi protein activation and consequent inhibition of soluble-adenylyl cyclase (sAC). The resulting inhibition of protein kinase A (PKA)-dependent phosphorylation of specific subunits of the mitochondrial electron transport system eventually leads to decreased cellular respiration. Hippocampal inhibition of sAC activity or manipulation of intra-mitochondrial PKA signalling or phosphorylation of the Complex I subunit NDUFS2 inhibit bioenergetic and amnesic effects of cannabinoids. Thus, the G protein-coupled mtCB1 receptors regulate memory processes via modulation of mitochondrial energy metabolism. By directly linking mitochondrial activity to memory formation, these data reveal that bioenergetic processes are primary acute regulators of cognitive functions.

  6. Memory-related brain lateralisation in birds and humans.

    PubMed

    Moorman, Sanne; Nicol, Alister U

    2015-03-01

    Visual imprinting in chicks and song learning in songbirds are prominent model systems for the study of the neural mechanisms of memory. In both systems, neural lateralisation has been found to be involved in memory formation. Although many processes in the human brain are lateralised--spatial memory and musical processing involves mostly right hemisphere dominance, whilst language is mostly left hemisphere dominant--it is unclear what the function of lateralisation is. It might enhance brain capacity, make processing more efficient, or prevent occurrence of conflicting signals. In both avian paradigms we find memory-related lateralisation. We will discuss avian lateralisation findings and propose that birds provide a strong model for studying neural mechanisms of memory-related lateralisation.

  7. Working memory and early numeracy training in preschool children.

    PubMed

    Passolunghi, Maria Chiara; Costa, Hiwet Mariam

    2016-01-01

    Many factors influence children's performance in mathematical achievement, including both domain-specific and domain-general factors. This study aimed to verify and compare the effects of two types of training on early numerical skills. One type of training focused on the enhancement of working memory, a domain-general precursor, while the other focused on the enhancement of early numeracy, a domain-specific precursor. The participants were 48 five-year-old preschool children. Both the working memory and early numeracy training programs were implemented for 5 weeks. The results showed that the early numeracy intervention specifically improved early numeracy abilities in preschool children, whereas working memory intervention improved not only working memory abilities but also early numeracy abilities. These findings stress the importance of performing activities designed to train working memory abilities, in addition to activities aimed to enhance more specific skills, in the early prevention of learning difficulties during preschool years.

  8. Distributed multiport memory architecture

    NASA Technical Reports Server (NTRS)

    Kohl, W. H. (Inventor)

    1983-01-01

    A multiport memory architecture is diclosed for each of a plurality of task centers connected to a command and data bus. Each task center, includes a memory and a plurality of devices which request direct memory access as needed. The memory includes an internal data bus and an internal address bus to which the devices are connected, and direct timing and control logic comprised of a 10-state ring counter for allocating memory devices by enabling AND gates connected to the request signal lines of the devices. The outputs of AND gates connected to the same device are combined by OR gates to form an acknowledgement signal that enables the devices to address the memory during the next clock period. The length of the ring counter may be effectively lengthened to any multiple of ten to allow for more direct memory access intervals in one repetitive sequence. One device is a network bus adapter which serially shifts onto the command and data bus, a data word (8 bits plus control and parity bits) during the next ten direct memory access intervals after it has been granted access. The NBA is therefore allocated only one access in every ten intervals, which is a predetermined interval for all centers. The ring counters of all centers are periodically synchronized by DMA SYNC signal to assure that all NBAs be able to function in synchronism for data transfer from one center to another.

  9. [Learning and memory].

    PubMed

    Lombroso, Paul

    2004-09-01

    Memory is broadly divided into declarative and nondeclarative forms of memory. The hippocampus is required for the formation of declarative memories, while a number of other brain regions including the striatum, amygdala and nucleus accumbens are involved in the formation of nondeclarative memories. The formation of all memories require morphological changes of synapses: new ones must be formed or old ones strengthened. These changes are thought to reflect the underlying cellular basis for persistent memories. Considerable advances have occurred over the last decade in our understanding of the molecular bases of how these memories are formed. A key regulator of synaptic plasticity is a signaling pathway that includes the mitogen activated protein (MAP) kinase. As this pathway is required for normal memory and learning, it is not surprising that mutations in members of this pathway lead to disruptions in learning. Neurofibromatosis, Coffin-Lowry syndrome and Rubinstein-Taybi syndrome are three examples of developmental disorders that have mutations in key components of the MAP kinase signaling pathway.

  10. Memory and Aging

    MedlinePlus

    ... or home environment and you’re not paying attention when your friend gives you directions to her new home, you will not be able to recall how to get there. Memory and Aging Memory Aids Keep “to do” lists Keep “to do” lists and ...

  11. Regret as Autobiographical Memory

    ERIC Educational Resources Information Center

    Davison, Ian M.; Feeney, Aidan

    2008-01-01

    We apply an autobiographical memory framework to the study of regret. Focusing on the distinction between regrets for specific and general events we argue that the temporal profile of regret, usually explained in terms of the action-inaction distinction, is predicted by models of autobiographical memory. In two studies involving participants in…

  12. Memories of Physical Education

    ERIC Educational Resources Information Center

    Sidwell, Amy M.; Walls, Richard T.

    2014-01-01

    The purpose of this investigation was to explore college students' autobiographical memories of physical education (PE). Questionnaires were distributed to students enrolled in undergraduate Introduction to PE and Introduction to Communications courses. The 261 participants wrote about memories of PE. These students recalled events from Grades…

  13. Predicting Reasoning from Memory

    ERIC Educational Resources Information Center

    Heit, Evan; Hayes, Brett K.

    2011-01-01

    In an effort to assess the relations between reasoning and memory, in 8 experiments, the authors examined how well responses on an inductive reasoning task are predicted from responses on a recognition memory task for the same picture stimuli. Across several experimental manipulations, such as varying study time, presentation frequency, and the…

  14. Experimental Optoelectronic Associative Memory

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin

    1992-01-01

    Optoelectronic associative memory responds to input image by displaying one of M remembered images. Which image to display determined by optoelectronic analog computation of resemblance between input image and each remembered image. Does not rely on precomputation and storage of outer-product synapse matrix. Size of memory needed to store and process images reduced.

  15. Memorial symptom assessment scale.

    PubMed

    Chang, Victor T; Hwang, Shirley S; Thaler, Howard T; Kasimis, Basil S; Portenoy, Russell K

    2004-04-01

    Patients with advanced illnesses often have multiple symptoms. As interest in palliative care and interventions for symptom control increase, the ability to assess multiple symptoms has become more important. A number of instruments have been developed to meet this need in cancer patients. This article reviews the development and applications of a multidimensional instrument, the Memorial Symptom Assessment Scale. The Memorial Symptom Assessment Scale has 32 symptoms and three dimensions of frequency, severity, and distress. Shorter versions - The Memorial Symptom Assessment Scale Short Form (32 symptoms with one dimension) and the Condensed Memorial Symptom Assessment Scale (14 symptoms with one dimension), and a version for children aged 7-12 years, have also been developed. A distinctive feature is the summary subscales for physical distress, psychological distress, and The Global Distress Index. The Memorial Symptom Assessment Scale has proven useful in description of symptom epidemiology, the role of symptoms in pain, fatigue, and spirituality; as a predictor of survival, and in proxy assessments of pain. The Memorial Symptom Assessment Scale has been used in studies of cancer and AIDS patients, and patients with advanced medical illnesses. Possible future roles of instruments such as the Memorial Symptom Assessment Scale include use in clinical trials, for pharmacoeconomic analyses, definition of symptom clusters and symptom burden, the development of symptom outcome measures, symptom monitoring, and improving care for patients. Continued research is needed for the versions of the Memorial Symptom Assessment Scale and other symptom instruments in different populations and applications.

  16. Visual Memory at Birth.

    ERIC Educational Resources Information Center

    Slater, Alan; And Others

    1982-01-01

    Explored new-born babys' capacity for forming visual memories. Used an habituation procedure that accommodated individual differences by allowing each infant to control the time course of habituation trials. Found significant novelty preference, providing strong evidence that recognition memory can be reliably demonstrated from birth. (Author/JAC)

  17. Human Learning and Memory

    ERIC Educational Resources Information Center

    Lieberman, David A.

    2012-01-01

    This innovative textbook is the first to integrate learning and memory, behaviour, and cognition. It focuses on fascinating human research in both memory and learning (while also bringing in important animal studies) and brings the reader up to date with the latest developments in the subject. Students are encouraged to think critically: key…

  18. Human Memory: The Basics

    ERIC Educational Resources Information Center

    Martinez, Michael E.

    2010-01-01

    The human mind has two types of memory: short-term and long-term. In all types of learning, it is best to use that structure rather than to fight against it. One way to do that is to ensure that learners can fit new information into patterns that can be stored in and more easily retrieved from long-term memory.

  19. Memory Efficient Ranking.

    ERIC Educational Resources Information Center

    Moffat, Alistair; And Others

    1994-01-01

    Describes an approximate document ranking process that uses a compact array of in-memory, low-precision approximations for document length. Combined with another rule for reducing the memory required by partial similarity accumulators, the approximation heuristic allows the ranking of large document collections using less than one byte of memory…

  20. Memory technology survey

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The current status of semiconductor, magnetic, and optical memory technologies is described. Projections based on these research activities planned for the shot term are presented. Conceptual designs of specific memory buffer pplications employing bipola, CMOS, GaAs, and Magnetic Bubble devices are discussed.

  1. An Exceptional Memory

    ERIC Educational Resources Information Center

    Hunter, Ian M. L.

    1977-01-01

    An account is given of the exceptional memory of the late Professor A. C. Aitken who was also a distinguished mathematician and mental calculator. Compared with Shereshevskii, another man with exceptional memory, he shows the scholar's reliance on conceptual mapping rather than the mnemonist's reliance on perceptual chaining. (Editor)

  2. Memory Metals (Marchon Eyewear)

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Another commercial application of memory metal technology is found in a "smart" eyeglass frame that remembers its shape and its wearer's fit. A patented "memory encoding process" makes this possible. Heat is not required to return the glasses to shape. A large commercial market is anticipated.

  3. A Space for Memory

    ERIC Educational Resources Information Center

    Charman, Karen

    2015-01-01

    In this article I examine the possibilities of reparation in an era of privatisation and de-industrialisation. I examine the effect of a recent project Sunshine Memory Space, a space, designed to evoke memories of a de-industrialised urban Melbourne suburb Sunshine. This project offered the opportunity for the effects of industrial change to be…

  4. Long-Term Memory for Different Types of Classroom Knowledge

    DTIC Science & Technology

    1992-08-01

    they start working on the job. However, much of the research on memory loss has focused on procedural/ psychomotor skills and tasks (e.g., performing...factors has focused on procedural/ psychomotor skills and tasks (e.g., performing preventive maintenance, operating equipment). After a number of...with an accompanying form, TRADOC Form 321-R. While the research on retention of procedural/ psychomotor skills has been extensive, memory for knowledge

  5. Animal models of source memory.

    PubMed

    Crystal, Jonathon D

    2016-01-01

    Source memory is the aspect of episodic memory that encodes the origin (i.e., source) of information acquired in the past. Episodic memory (i.e., our memories for unique personal past events) typically involves source memory because those memories focus on the origin of previous events. Source memory is at work when, for example, someone tells a favorite joke to a person while avoiding retelling the joke to the friend who originally shared the joke. Importantly, source memory permits differentiation of one episodic memory from another because source memory includes features that were present when the different memories were formed. This article reviews recent efforts to develop an animal model of source memory using rats. Experiments are reviewed which suggest that source memory is dissociated from other forms of memory. The review highlights strengths and weaknesses of a number of animal models of episodic memory. Animal models of source memory may be used to probe the biological bases of memory. Moreover, these models can be combined with genetic models of Alzheimer's disease to evaluate pharmacotherapies that ultimately have the potential to improve memory.

  6. Is random access memory random?

    NASA Technical Reports Server (NTRS)

    Denning, P. J.

    1986-01-01

    Most software is contructed on the assumption that the programs and data are stored in random access memory (RAM). Physical limitations on the relative speeds of processor and memory elements lead to a variety of memory organizations that match processor addressing rate with memory service rate. These include interleaved and cached memory. A very high fraction of a processor's address requests can be satified from the cache without reference to the main memory. The cache requests information from main memory in blocks that can be transferred at the full memory speed. Programmers who organize algorithms for locality can realize the highest performance from these computers.

  7. Predicting reasoning from memory.

    PubMed

    Heit, Evan; Hayes, Brett K

    2011-02-01

    In an effort to assess the relations between reasoning and memory, in 8 experiments, the authors examined how well responses on an inductive reasoning task are predicted from responses on a recognition memory task for the same picture stimuli. Across several experimental manipulations, such as varying study time, presentation frequency, and the presence of stimuli from other categories, there was a high correlation between reasoning and memory responses (average r = .87), and these manipulations showed similar effects on the 2 tasks. The results point to common mechanisms underlying inductive reasoning and recognition memory abilities. A mathematical model, GEN-EX (generalization from examples), derived from exemplar models of categorization, is presented, which predicts both reasoning and memory responses from pairwise similarities among the stimuli, allowing for additional influences of subtyping and deterministic responding.

  8. Computer memory management system

    DOEpatents

    Kirk, III, Whitson John

    2002-01-01

    A computer memory management system utilizing a memory structure system of "intelligent" pointers in which information related to the use status of the memory structure is designed into the pointer. Through this pointer system, The present invention provides essentially automatic memory management (often referred to as garbage collection) by allowing relationships between objects to have definite memory management behavior by use of coding protocol which describes when relationships should be maintained and when the relationships should be broken. In one aspect, the present invention system allows automatic breaking of strong links to facilitate object garbage collection, coupled with relationship adjectives which define deletion of associated objects. In another aspect, The present invention includes simple-to-use infinite undo/redo functionality in that it has the capability, through a simple function call, to undo all of the changes made to a data model since the previous `valid state` was noted.

  9. Memory B cells.

    PubMed

    Kurosaki, Tomohiro; Kometani, Kohei; Ise, Wataru

    2015-03-01

    The immune system can remember a previously experienced pathogen and can evoke an enhanced response to reinfection that depends on memory lymphocyte populations. Recent advances in tracking antigen-experienced memory B cells have revealed the existence of distinct classes of cells that have considerable functional differences. Some of these differences seem to be determined by the stimulation history during memory cell formation. To induce rapid recall antibody responses, the contributions of other types of cells, such as memory T follicular helper cells, have also now begun to be appreciated. In this Review, we discuss these and other recent advances in our understanding of memory B cells, focusing on the underlying mechanisms that are required for rapid and effective recall antibody responses.

  10. Serotonin transporter and memory.

    PubMed

    Meneses, Alfredo; Perez-Garcia, Georgina; Ponce-Lopez, Teresa; Tellez, Ruth; Castillo, Carlos

    2011-09-01

    The serotonin transporter (SERT) has been associated to diverse functions and diseases, though seldom to memory. Therefore, we made an attempt to summarize and discuss the available publications implicating the involvement of the SERT in memory, amnesia and anti-amnesic effects. Evidence indicates that Alzheimer's disease and drugs of abuse like d-methamphetamine (METH) and (+/-)3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") have been associated to decrements in the SERT expression and memory deficits. Several reports have indicated that memory formation and amnesia affected the SERT expression. The SERT expression seems to be a reliable neural marker related to memory mechanisms, its alterations and potential treatment. The pharmacological, neural and molecular mechanisms associated to these changes are of great importance for investigation.

  11. Cosmological memory effect

    NASA Astrophysics Data System (ADS)

    Tolish, Alexander; Wald, Robert M.

    2016-08-01

    The "memory effect" is the permanent change in the relative separation of test particles resulting from the passage of gravitational radiation. We investigate the memory effect for a general, spatially flat Friedmann-Lemaître-Robertson-Walker (FLRW) cosmology by considering the radiation associated with emission events involving particle-like sources. We find that if the resulting perturbation is decomposed into scalar, vector, and tensor parts, only the tensor part contributes to memory. Furthermore, the tensor contribution to memory depends only on the cosmological scale factor at the source and observation events, not on the detailed expansion history of the universe. In particular, for sources at the same luminosity distance, the memory effect in a spatially flat FLRW spacetime is enhanced over the Minkowski case by a factor of (1 +z ).

  12. Imaging autobiographical memory.

    PubMed

    Fossati, Philippe

    2013-12-01

    Autobiographical memory (AM) defines the memory systems that encode, consolidate, and retrieve personal events and facts, AM is strongly related to self-perception and self representation. We review here the neural correlates of AM retrieval. AM retrieval encompasses a large neural network including the prefrontal, temporal, and parietal cortex, and limbic structures. All these regions subserve the cognitive processes (episodic remembering, cognitive control, self-processing, and scene construction) at play during memory retrieval. We emphasize the specific role of medial prefrontal cortex and precuneus in self-processing during autobiographical memory retrieval. Overall, these data call for further studies in psychiatric patients, to investigate the neural underpinnings of autobiographical memory and self-representation in mental disorders.

  13. Innate Memory T cells

    PubMed Central

    Jameson, Stephen C.; Lee, You Jeong; Hogquist, Kristin A.

    2015-01-01

    Memory T cells are usually considered to be a feature of a successful immune response against a foreign antigen, and such cells can mediate potent immunity. However, in mice, alternative pathways have been described, through which naïve T cells can acquire the characteristics and functions of memory T cells without encountering specific foreign antigen or the typical signals required for conventional T cell differentiation. Such cells reflect a response to the internal rather the external environment, and hence such cells are called innate memory T cells. In this review, we describe how innate memory subsets were identified, the signals that induce their generation and their functional properties and potential role in the normal immune response. The existence of innate memory T cells in mice raises questions about whether parallel populations exist in humans, and we discuss the evidence for such populations during human T cell development and differentiation. PMID:25727290

  14. Preventative Maintenance.

    ERIC Educational Resources Information Center

    Migliorino, James

    Boards of education must be convinced that spending money up front for preventive maintenance will, in the long run, save districts' tax dollars. A good program of preventive maintenance can minimize disruption of service; reduce repair costs, energy consumption, and overtime; improve labor productivity and system equipment reliability; handle…

  15. Oculomotor preparation as a rehearsal mechanism in spatial working memory.

    PubMed

    Pearson, David G; Ball, Keira; Smith, Daniel T

    2014-09-01

    There is little consensus regarding the specific processes responsible for encoding, maintenance, and retrieval of information in visuo-spatial working memory (VSWM). One influential theory is that VSWM may involve activation of the eye-movement (oculomotor) system. In this study we experimentally prevented healthy participants from planning or executing saccadic eye-movements during the encoding, maintenance, and retrieval stages of visual and spatial working memory tasks. Participants experienced a significant reduction in spatial memory span only when oculomotor preparation was prevented during encoding or maintenance. In contrast there was no reduction when oculomotor preparation was prevented only during retrieval. These results show that (a) involvement of the oculomotor system is necessary for optimal maintenance of directly-indicated locations in spatial working memory and (b) oculomotor preparation is not necessary during retrieval from spatial working memory. We propose that this study is the first to unambiguously demonstrate that the oculomotor system contributes to the maintenance of spatial locations in working memory independently from the involvement of covert attention.

  16. Memory retrieval time and memory capacity of the CA3 network: Role of gamma frequency oscillations

    PubMed Central

    de Almeida, Licurgo; Idiart, Marco; Lisman, John E.

    2007-01-01

    The existence of recurrent synaptic connections in CA3 led to the hypothesis that CA3 is an autoassociative network similar to the Hopfield networks studied by theorists. CA3 undergoes gamma frequency periodic inhibition that prevents a persistent attractor state. This argues against the analogy to Hopfield nets, in which an attractor state can be used for working memory. However, we show that such periodic inhibition allows one cycle of recurrent excitatory activity and that this is sufficient for memory retrieval (within milliseconds). Thus, gamma oscillations are compatible with a long-term autoassociative memory function for CA3. A second goal of our work was to evaluate previous methods for estimating the memory capacity (P) of CA3. We confirm the equation, P = c/a2, where c is the probability that any two cells are recurrently connected and a is the fraction of cells representing a memory item. In applying this to CA3, we focus on CA3a, the subregion where recurrent connections are most numerous (c = 0.2) and approximate randomness. We estimate that a memory item is represented by ∼225 of the 70,000 neurons in CA3a (a = 0.003) and that ∼20,000 memory items can be stored. Our general conclusion is that the physiological and anatomical findings of CA3a are consistent with an autoassociative function. The nature of the information that is associated in CA3a is discussed. We also discuss how the autoassociative properties of CA3 and the heteroassociative properties of dentate synapses (linking sequential memories) form an integrated system for the storage and recall of item sequences. The recall process generates the phase precession in dentate, CA3, and entorhinal cortex. PMID:18007022

  17. Aging Memories: Differential Decay of Episodic Memory Components

    ERIC Educational Resources Information Center

    Talamini, Lucia M.; Gorree, Eva

    2012-01-01

    Some memories about events can persist for decades, even a lifetime. However, recent memories incorporate rich sensory information, including knowledge on the spatial and temporal ordering of event features, while old memories typically lack this "filmic" quality. We suggest that this apparent change in the nature of memories may reflect a…

  18. Single-Item Memory, Associative Memory, and the Human Hippocampus

    ERIC Educational Resources Information Center

    Squire, Larry R.; Gold, Jeffrey J.; Hopkins, Ramona O.

    2006-01-01

    We tested recognition memory for items and associations in memory-impaired patients with bilateral lesions thought to be limited to the hippocampal region. In Experiment 1 (Combined memory test), participants studied words and then took a memory test in which studied words, new words, studied word pairs, and recombined word pairs were presented in…

  19. Contextual Information Drives the Reconsolidation-Dependent Updating of Retrieved Fear Memories

    PubMed Central

    Jarome, Timothy J; Ferrara, Nicole C; Kwapis, Janine L; Helmstetter, Fred J

    2015-01-01

    Stored memories enter a temporary state of vulnerability following retrieval known as ‘reconsolidation', a process that can allow memories to be modified to incorporate new information. Although reconsolidation has become an attractive target for treatment of memories related to traumatic past experiences, we still do not know what new information triggers the updating of retrieved memories. Here, we used biochemical markers of synaptic plasticity in combination with a novel behavioral procedure to determine what was learned during memory reconsolidation under normal retrieval conditions. We eliminated new information during retrieval by manipulating animals' training experience and measured changes in proteasome activity and GluR2 expression in the amygdala, two established markers of fear memory lability and reconsolidation. We found that eliminating new contextual information during the retrieval of memories for predictable and unpredictable fear associations prevented changes in proteasome activity and glutamate receptor expression in the amygdala, indicating that this new information drives the reconsolidation of both predictable and unpredictable fear associations on retrieval. Consistent with this, eliminating new contextual information prior to retrieval prevented the memory-impairing effects of protein synthesis inhibitors following retrieval. These results indicate that under normal conditions, reconsolidation updates memories by incorporating new contextual information into the memory trace. Collectively, these results suggest that controlling contextual information present during retrieval may be a useful strategy for improving reconsolidation-based treatments of traumatic memories associated with anxiety disorders such as post-traumatic stress disorder. PMID:26062788

  20. Memory, language, and ageing.

    PubMed Central

    Burke, D M; Mackay, D G

    1997-01-01

    This overview provides both theoretical and empirical reasons for emphasizing practice and familiar skills as a practical strategy for enhancing cognitive functioning in old age. Our review of empirical research on age-related changes in memory and language reveals a consistent pattern of spared and impaired abilities in normal old age. Relatively preserved in old age is memory performance involving highly practised skills and familiar information, including factual, semantic and autobiographical information. Relatively impaired in old age is memory performance that requires the formation of new connections, for example, recall of recent autobiographical experiences, new facts or the source of newly acquired facts. This pattern of impaired new learning versus preserved old learning cuts across distinctions between semantic memory, episodic memory, explicit memory and perhaps also implicit memory. However, familiar verbal information is not completely preserved when accessed on the output side rather than the input side: aspects of language production, namely word finding and spelling, exhibit significant age-related declines. This emerging pattern of preserved and impaired abilities presents a fundamental challenge for theories of cognitive ageing, which must explain why some aspects of language and memory are more vulnerable to the effects of ageing than others. Information-universal theories, involving mechanisms such as general slowing that are independent of the type or structure of the information being processed, require additional mechanisms to account for this pattern of cognitive aging. Information-specific theories, where the type or structure of the postulated memory units can influence the effects of cognitive ageing, are able to account for this emerging pattern, but in some cases require further development to account for comprehensive cognitive changes such as general slowing. PMID:9460069

  1. Sleep and memory.

    PubMed

    Roth, T; Roehrs, T; Zwyghuizen-Doorenbos, A; Stepanski, E; Wittig, R

    1988-01-01

    Generally sleep is considered a time of amnesia. It is not uncommon for an individual to experience 8 h of sleep and have no memory for events during that time. Similarly, a substantial proportion of the population has no memory for dreams that occurred during the night, despite the fact that the literature on awakening during rapid eye movement (REM) sleep clearly shows that individuals normally have four to six "dream experiences" a night. Research on this issue seems to indicate that the lack of memory cannot be explained by the organisms' inability to perceive stimuli. The data indicate that although perceptual thresholds are elevated, organisms can clearly perceive stimuli, and, in fact, can discriminate between them during sleep. The amnesia also cannot be explained by a defect in long-term memory, as studies have indicated that stimuli put into the memory during wakefulness are more efficiently retrieved after a sleep period than after a comparable period of wakefulness. The most likely explanation for the amnestic property of sleep seems to be the inability of organisms to transfer information from short-term memory to long-term memory during sleep. There are several sources of evidence to support this hypothesis. First, the probability of remembering a stimulus given during wakefulness is related to the proximity of sleep onset to the stimulus. Generally, information put into the system within 5 min of sleep onset is lost from memory. Secondly, disorders of excessive daytime somnolence which cause individuals to have frequent microsleeps are often associated with complains of memory problems.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Plated wire memory subsystem

    NASA Technical Reports Server (NTRS)

    Carpenter, K. H.

    1974-01-01

    The design, construction, and test history of a 4096 word by 18 bit random access NDRO Plated Wire Memory for use in conjunction with a spacecraft input/output and central processing unit is reported. A technical and functional description is given along with diagrams illustrating layout and systems operation. Test data is shown on the procedures and results of system level and memory stack testing, and hybrid circuit screening. A comparison of the most significant physical and performance characteristics of the memory unit versus the specified requirements is also included.

  3. Prevent Cyberbullying

    MedlinePlus

    ... Policies & Laws | Español Search Stopbullying.gov WHAT IS BULLYING Definition The Roles Kids Play Other Types of Aggressive Behavior CYBER BULLYING What is Cyberbullying? Prevent Cyberbullying Report Cyberbullying WHO ...

  4. Preventing Influenza

    MedlinePlus

    ... spread in respiratory droplets distributed by coughing and sneezing, they readily spread from person to person. Additionally, ... and nose with a tissue when coughing or sneezing, you may help prevent those around you from ...

  5. Enhanced memory persistence is blocked by a DNA methyltransferase inhibitor in the snail Lymnaea stagnalis.

    PubMed

    Lukowiak, Ken; Heckler, Benjamin; Bennett, Thomas E; Schriner, Ellen K; Wyrick, Kathryn; Jewett, Cynthia; Todd, Ryan P; Sorg, Barbara A

    2014-08-15

    Lymnaea stagnalis provides an excellent model system for studying memory because these snails have a well-described set of neurons, a single one of which controls expression of long-term memory of operantly conditioned respiratory behavior. We have shown that several different manipulations, including pre-training exposure to serotonin (5-HT) or methamphetamine, submersion of snails after training to prevent memory interference, and exposure to effluent from predatory crayfish (CE), enhance memory persistence. Changes in DNA methylation underlie formation of strong memories in mammals and 5-HT-enhanced long-term facilitation in Aplysia. Here we determined the impact of the DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (5-AZA; 87 μmol l(-1)), on enhanced memory persistence by all four manipulations. We found that 5-HT (100 μmol l(-1)) enhanced memory persistence, which was blocked by 5-AZA pretreatment. Snails pre-exposed to 3.3 μmol l(-1) Meth 4 h prior to training demonstrated memory 72 h later, which was not present in controls. This memory-enhancing effect was blocked by pre-treatment with 87 μmol l(-1) 5-AZA. Similarly, submersion to prevent interference learning as well as training in CE produced memory that was not present in controls, and these effects were blocked by pre-treatment with 87 μmol l(-1) 5-AZA. In contrast, 5-AZA injection did not alter expression of normal (non-enhanced) memory, suggesting that these four stimuli enhance memory persistence by increasing DNA methyltransferase activity, which, in turn, increases expression of memory-enhancing genes and/or inhibits memory suppressor genes. These studies lay important groundwork for delineating gene methylation changes that are common to persistent memory produced by different stimuli.

  6. Memory Retrieval as Temporal Discrimination

    ERIC Educational Resources Information Center

    Brown, Gordon D. A.; Vousden, Janet I.; McCormack, Teresa

    2009-01-01

    Temporal distinctiveness models of memory retrieval claim that memories are organised partly in terms of their positions along a temporal dimension, and suggest that memory retrieval involves temporal discrimination. According to such models the retrievability of memories should be related to the discriminability of their temporal distances at the…

  7. Reduced False Memory after Sleep

    ERIC Educational Resources Information Center

    Fenn, Kimberly M.; Gallo, David A.; Margoliash, Daniel; Roediger, Henry L., III; Nusbaum, Howard C.

    2009-01-01

    Several studies have shown that sleep contributes to the successful maintenance of previously encoded information. This research has focused exclusively on memory for studied events, as opposed to false memories. Here we report three experiments showing that sleep reduces false memories in the Deese-Roediger-McDermott (DRM) memory illusion. False…

  8. Prospective memory: A comparative perspective

    PubMed Central

    Crystal, Jonathon D.; Wilson, A. George

    2014-01-01

    Prospective memory consists of forming a representation of a future action, temporarily storing that representation in memory, and retrieving it at a future time point. Here we review the recent development of animal models of prospective memory. We review experiments using rats that focus on the development of time-based and event-based prospective memory. Next, we review a number of prospective-memory approaches that have been used with a variety of non-human primates. Finally, we review selected approaches from the human literature on prospective memory to identify targets for development of animal models of prospective memory. PMID:25101562

  9. Positive consequences of false memories.

    PubMed

    Howe, Mark L; Garner, Sarah R; Patel, Megan

    2013-01-01

    Previous research is replete with examples of the negative consequences of false memories. In the current research, we provide a different perspective on false memories and their development and demonstrate that false memories can have positive consequences. Specifically, we examined the role false memories play in subsequent problem-solving tasks. Children and adults studied and recalled neutral or survival-relevant lists of associated words. They then solved age-normed compound remote associates, some of whose solutions had been primed by false memories created when studying the previous lists. The results showed that regardless of age: (a) survival-related words were not only better recollected but were also more susceptible than neutral words to false memory illusions; and (b) survival-related false memories were better than neutral false memories as primes for problem-solving. These findings are discussed in the context of recent speculation concerning the positive consequences of false memories, and the adaptive nature of reconstructive memory.

  10. Medications for Memory Loss

    MedlinePlus

    ... memory loss, confusion, and problems with thinking and reasoning) of Alzheimer's disease. There is also a medication ... the latest Alzheimer's medications available today, and the clinical trials that may bring us closer to new ...

  11. Memory Circuit Fault Simulator

    NASA Technical Reports Server (NTRS)

    Sheldon, Douglas J.; McClure, Tucker

    2013-01-01

    Spacecraft are known to experience significant memory part-related failures and problems, both pre- and postlaunch. These memory parts include both static and dynamic memories (SRAM and DRAM). These failures manifest themselves in a variety of ways, such as pattern-sensitive failures, timingsensitive failures, etc. Because of the mission critical nature memory devices play in spacecraft architecture and operation, understanding their failure modes is vital to successful mission operation. To support this need, a generic simulation tool that can model different data patterns in conjunction with variable write and read conditions was developed. This tool is a mathematical and graphical way to embed pattern, electrical, and physical information to perform what-if analysis as part of a root cause failure analysis effort.

  12. Working Memory and Neurofeedback.

    PubMed

    YuLeung To, Eric; Abbott, Kathy; Foster, Dale S; Helmer, D'Arcy

    2016-01-01

    Impairments in working memory are typically associated with impairments in other cognitive faculties such as attentional processes and short-term memory. This paper briefly introduces neurofeedback as a treatment modality in general, and, more specifically, we review several of the current modalities successfully used in neurofeedback (NF) for the treatment of working memory deficits. Two case studies are presented to illustrate how neurofeedback is applied in treatment. The development of Low Resolution Electromagnetic Tomography (LORETA) and its application in neurofeedback now makes it possible to specifically target deep cortical/subcortical brain structures. Developments in neuroscience concerning neural networks, combined with highly specific yet practical NF technologies, makes neurofeedback of particular interest to neuropsychological practice, including the emergence of specific methodologies for treating very difficult working memory (WM) problems.

  13. Magnetic vortex racetrack memory

    NASA Astrophysics Data System (ADS)

    Geng, Liwei D.; Jin, Yongmei M.

    2017-02-01

    We report a new type of racetrack memory based on current-controlled movement of magnetic vortices in magnetic nanowires with rectangular cross-section and weak perpendicular anisotropy. Data are stored through the core polarity of vortices and each vortex carries a data bit. Besides high density, non-volatility, fast data access, and low power as offered by domain wall racetrack memory, magnetic vortex racetrack memory has additional advantages of no need for constrictions to define data bits, changeable information density, adjustable current magnitude for data propagation, and versatile means of ultrafast vortex core switching. By using micromagnetic simulations, current-controlled motion of magnetic vortices in cobalt nanowire is demonstrated for racetrack memory applications.

  14. Serriform Strip Crosstie Memory.

    DTIC Science & Technology

    edge effect of the margin serrations upon magnetization, a form of shape anisotropy, inherently defines memory cell boundaries in the domain walls, thereby giving the crossties and Bloch lines preferred locations and allowing the use of a simplified propagation

  15. Multiresonator quantum memory

    NASA Astrophysics Data System (ADS)

    Moiseev, S. A.; Gubaidullin, F. F.; Kirillov, R. S.; Latypov, R. R.; Perminov, N. S.; Petrovnin, K. V.; Sherstyukov, O. N.

    2017-01-01

    In this paper we present universal broadband multiresonator quantum memory based on the spatial-frequency combs of the microresonators coupled with a common waveguide. We find a Bragg-type impedance matching condition for the coupling of the microresonators with a waveguide field that provides an efficient broadband quantum storage. The analytical solution obtained for the microresonator fields enables sustainable parametric control of all the memory characteristics. We also construct an experimental prototype of the studied quantum memory in the microwave spectral range that demonstrates basic properties of the microwave microresonators, their coupling with a common waveguide, and independent control of the microresonator frequencies. Experimentally observed narrow lines of the microresonators confirm the possibility of multiresonator quantum memory implementation.

  16. Memory, Memoir, Story.

    ERIC Educational Resources Information Center

    Johnson, Nancy J.; Giorgis, Cyndi

    2000-01-01

    Offers brief descriptions of 41 good books for children offering a treasury of memory, memoir, and stories. Presents books in the following categories: storytellers, folktales, voices, family, artifacts, and preservation. (SR)

  17. Coping with Memory Loss

    MedlinePlus

    ... either using computerized axial tomography (CAT) scans or magnetic resonance imaging (MRI) – can help to identify strokes and tumors, which can sometimes cause memory loss. “The goal is to rule out factors ...

  18. Perception and Memory of Pictures

    DTIC Science & Technology

    1991-08-20

    altogether. His explanation for the efftct is similar to that proposed by Raijmakers and Shiffrin (1981) in the SAM model of memory : Items from...implicit memory , explicit memory , recognition memory , perce ’ptual fluency, priming, RSVP, fragmented pictures, connectionist models , PDP models 19...of implicit and explicit memory . A connectionist model of picture recognition which was developed and tested in collaboration with Elliot Hirshman

  19. Plated wire memory subsystem

    NASA Technical Reports Server (NTRS)

    Reynolds, L.; Tweed, H.

    1972-01-01

    The work performed entailed the design, development, construction and testing of a 4000 word by 18 bit random access, NDRO plated wire memory for use in conjunction with a spacecraft imput/output unit and central processing unit. The primary design parameters, in order of importance, were high reliability, low power, volume and weight. A single memory unit, referred to as a qualification model, was delivered.

  20. Epigenetic memory in plants.

    PubMed

    Iwasaki, Mayumi; Paszkowski, Jerzy

    2014-09-17

    Epigenetics refers to heritable changes in patterns of gene expression that occur without alterations in DNA sequence. The epigenetic mechanisms involve covalent modifications of DNA and histones, which affect transcriptional activity of chromatin. Since chromatin states can be propagated through mitotic and meiotic divisions, epigenetic mechanisms are thought to provide heritable 'cellular memory'. Here, we review selected examples of epigenetic memory in plants and briefly discuss underlying mechanisms.

  1. Emergence of Collective Memories

    PubMed Central

    Lee, Sungmin; Ramenzoni, Verónica C.; Holme, Petter

    2010-01-01

    Background We understand the dynamics of the world around us as by associating pairs of events, where one event has some influence on the other. These pairs of events can be aggregated into a web of memories representing our understanding of an episode of history. The events and the associations between them need not be directly experienced—they can also be acquired by communication. In this paper we take a network approach to study the dynamics of memories of history. Methodology/Principal Findings First we investigate the network structure of a data set consisting of reported events by several individuals and how associations connect them. We focus our measurement on degree distributions, degree correlations, cycles (which represent inconsistencies as they would break the time ordering) and community structure. We proceed to model effects of communication using an agent-based model. We investigate the conditions for the memory webs of different individuals to converge to collective memories, how groups where the individuals have similar memories (but different from other groups) can form. Conclusions/Significance Our work outlines how the cognitive representation of memories and social structure can co-evolve as a contagious process. We generate some testable hypotheses including that the number of groups is limited as a function of the total population size. PMID:20824141

  2. Mechanisms of Memory Enhancement

    PubMed Central

    Stern, Sarah A.

    2012-01-01

    The ongoing quest for memory enhancement is one that grows necessary as the global population increasingly ages. The extraordinary progress that has been made in the past few decades elucidating the underlying mechanisms of how long-term memories are formed has provided insight into how memories might also be enhanced. Capitalizing on this knowledge, it has been postulated that targeting many of the same mechanisms, including CREB activation, AMPA/NMDA receptor trafficking, neuromodulation (e.g. via dopamine, adrenaline, cortisol or acetylcholine) and metabolic processes (e.g. via glucose and insulin) may all lead to the enhancement of memory. These and other mechanisms and/or approaches have been tested via genetic or pharmacological methods in animal models, and several have been investigated in humans as well. In addition, a number of behavioral methods, including exercise and reconsolidation, may also serve to strengthen and enhance memories. By capitalizing on this knowledge and continuing to investigate these promising avenues, memory enhancement may indeed be achieved in the future. PMID:23151999

  3. Music evokes vivid autobiographical memories.

    PubMed

    Belfi, Amy M; Karlan, Brett; Tranel, Daniel

    2016-08-01

    Music is strongly intertwined with memories-for example, hearing a song from the past can transport you back in time, triggering the sights, sounds, and feelings of a specific event. This association between music and vivid autobiographical memory is intuitively apparent, but the idea that music is intimately tied with memories, seemingly more so than other potent memory cues (e.g., familiar faces), has not been empirically tested. Here, we compared memories evoked by music to those evoked by famous faces, predicting that music-evoked autobiographical memories (MEAMs) would be more vivid. Participants listened to 30 songs, viewed 30 faces, and reported on memories that were evoked. Memories were transcribed and coded for vividness as in Levine, B., Svoboda, E., Hay, J. F., Winocur, G., & Moscovitch, M. [2002. Aging and autobiographical memory: Dissociating episodic from semantic retrieval. Psychology and Aging, 17, 677-689]. In support of our hypothesis, MEAMs were more vivid than autobiographical memories evoked by faces. MEAMs contained a greater proportion of internal details and a greater number of perceptual details, while face-evoked memories contained a greater number of external details. Additionally, we identified sex differences in memory vividness: for both stimulus categories, women retrieved more vivid memories than men. The results show that music not only effectively evokes autobiographical memories, but that these memories are more vivid than those evoked by famous faces.

  4. Retrieval is not necessary to trigger reconsolidation of object recognition memory in the perirhinal cortex

    PubMed Central

    Santoyo-Zedillo, Marianela; Rodriguez-Ortiz, Carlos J.; Chavez-Marchetta, Gianfranco; Bermudez-Rattoni, Federico

    2014-01-01

    Memory retrieval has been considered as requisite to initiate memory reconsolidation; however, some studies indicate that blocking retrieval does not prevent memory from undergoing reconsolidation. Since N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors in the perirhinal cortex have been involved in object recognition memory formation, the present study evaluated whether retrieval and reconsolidation are independent processes by manipulating these glutamate receptors. The results showed that AMPA receptor antagonist infusions in the perirhinal cortex blocked retrieval, but did not affect memory reconsolidation, although NMDA receptor antagonist infusions disrupted reconsolidation even if retrieval was blocked. Importantly, neither of these antagonists disrupted short-term memory. These data suggest that memory underwent reconsolidation even in the absence of retrieval. PMID:25128536

  5. Effects of aging and working memory demands on prospective memory.

    PubMed

    West, Robert; Bowry, Ritvij

    2005-11-01

    The current study used event-related brain potentials (ERPs) to examine the effects of aging, increasing the working memory demands of the ongoing activity, and a prospective memory load on the neural correlates of prospective remembering and target recognition. The behavioral data revealed that the success of prospective memory was sensitive to working memory load in younger, but not older, adults and that a prospective memory load had a greater effect on the performance of older adults than that of younger adults. The ERP data revealed age-related differences in the neural correlates of the detection of prospective cues, post-retrieval processes that support prospective memory, and target recognition. Our results support the hypothesis that there are age-related differences in the ability to recruit preparatory attentional processes that underlie prospective memory, and demonstrate that younger and older adults may recruit somewhat different neural generators to support prospective memory and working memory.

  6. Usage of semantic representations in recognition memory.

    PubMed

    Nishiyama, Ryoji; Hirano, Tetsuji; Ukita, Jun

    2017-04-11

    Meanings of words facilitate false acceptance as well as correct rejection of lures in recognition memory tests, depending on the experimental context. This suggests that semantic representations are both directly and indirectly (i.e., mediated by perceptual representations) used in remembering. Studies using memory conjunction errors (MCEs) paradigms, in which the lures consist of component parts of studied words, have reported semantic facilitation of rejection of the lures. However, attending to components of the lures could potentially cause this. Therefore, we investigated whether semantic overlap of lures facilitates MCEs using Japanese Kanji words in which a whole-word image is more concerned in reading. Experiments demonstrated semantic facilitation of MCEs in a delayed recognition test (Experiment 1), and in immediate recognition tests in which participants were prevented from using phonological or orthographic representations (Experiment 2), and the salient effect on individuals with high semantic memory capacities (Experiment 3). Additionally, analysis of the receiver operating characteristic suggested that this effect is attributed to familiarity-based memory judgement and phantom recollection. These findings indicate that semantic representations can be directly used in remembering, even when perceptual representations of studied words are available.

  7. Hibernation does not affect memory retention in bats.

    PubMed

    Ruczynski, Ireneusz; Siemers, Björn M

    2011-02-23

    Long-term memory can be critically important for animals in a variety of contexts, and yet the extreme reduction in body temperature in hibernating animals alters neurochemistry and may therefore impair brain function. Behavioural studies on memory impairment associated with hibernation have been almost exclusively conducted on ground squirrels (Rodentia) and provide conflicting results, including clear evidence for memory loss. Here, we for the first time tested memory retention after hibernation for a vertebrate outside rodents-bats (Chiroptera). In the light of the high mobility, ecology and long life of bats, we hypothesized that maintenance of consolidated memory through hibernation is under strong natural selection. We trained bats to find food in one out of three maze arms. After training, the pre-hibernation performance of all individuals was at 100 per cent correct decisions. After this pre-test, one group of bats was kept, with two interruptions, at 7°C for two months, while the other group was kept under conditions that prevented them from going into hibernation. The hibernated bats performed at the same high level as before hibernation and as the non-hibernated controls. Our data suggest that bats benefit from an as yet unknown neuroprotective mechanism to prevent memory loss in the cold brain.

  8. The sensorimotor contributions to implicit memory, familiarity, and recollection.

    PubMed

    Topolinski, Sascha

    2012-05-01

    The sensorimotor contributions to memory for prior occurrence were investigated. Previous research has shown that both implicit memory and familiarity draw on gains in stimulus-related processing fluency for old, compared with novel, stimuli, but recollection does not. Recently, it has been demonstrated that processing fluency itself resides in stimulus-specific motor simulations or reenactment (e.g., covert pronouncing simulations for words as stimuli). Combining these lines of evidence, it was predicted that stimulus-specific motor interference preventing simulations should impair both implicit memory and familiarity but leave recollection unaffected. This was tested for words as verbal stimuli associated to pronouncing simulations in the oral muscle system (but also for tunes as vocal stimuli and their associated vocal system, Experiment 2). It was found that oral (e.g., chewing gum), compared with manual (kneading a ball), motor interference prevented mere exposure effects (Experiments 1-2), substantially reduced repetition priming in word fragment completion (Experiment 3), reduced the familiarity estimates in a remember-know task (Experiment 5) and in receiver-operating characteristics (Experiment 6), and completely neutralized familiarity measured by self-reports (Experiment 4) and skin conductance responses (Experiment 7), while leaving recollection and free recall unaffected (across Experiments 1-7). This pattern establishes a rare memory dissociation in healthy participants, that is, explicit without implicit memory or recognizing without feeling familiar. Implications for embodied memory and neuropsychology are discussed.

  9. False memories for aggressive acts.

    PubMed

    Laney, Cara; Takarangi, Melanie K T

    2013-06-01

    Can people develop false memories for committing aggressive acts? How does this process compare to developing false memories for victimhood? In the current research we used a simple false feedback procedure to implant false memories for committing aggressive acts (causing a black eye or spreading malicious gossip) or for victimhood (receiving a black eye). We then compared these false memories to other subjects' true memories for equivalent events. False aggressive memories were all too easy to implant, particularly in the minds of individuals with a proclivity towards aggression. Once implanted, the false memories were indistinguishable from true memories for the same events, on several dimensions, including emotional content. Implications for aggression-related memory more generally as well as false confessions are discussed.

  10. What people believe about memory.

    PubMed

    Magnussen, Svein; Andersson, Jan; Cornoldi, Cesare; De Beni, Rossana; Endestad, Tor; Goodman, Gail S; Helstrup, Tore; Koriat, Asher; Larsson, Maria; Melinder, Annika; Nilsson, Lars-Göran; Rönnberg, Jerker; Zimmer, Hubert

    2006-07-01

    Two representative samples of adult Norwegians (n=2000) were asked a set of general and specific questions regarding their beliefs and opinions about human memory. The results indicate that on many questions, such as time of the earliest memories, inhibiting effects of collaboration, and memory for dramatic versus ordinary events, the views of the general public concurred with current research findings, and people in general had realistic views about their own memory performance. On other questions, such as the reliability of olfactory as compared with visual and auditory memory, the memory of small children in comparison with that of adults, the likelihood of repression of adult traumatic memories, and on more general questions such as the possibility of training memory and the capacity limitations of long-term memory, a large proportion of the participants expressed views that are less supported by scientific evidence. Implications of these findings are briefly discussed.

  11. Dr. Worta McCaskill-Stevens Named Recipient of AACR Minorities in Cancer Research Award | Division of Cancer Prevention

    Cancer.gov

    Worta McCaskill-Stevens, MD, MS, Chief of the Community Oncology and Prevention Trials Research Group, NCI Division of Cancer Prevention, was named the recipient of the 2016 American Association for Cancer Research Jane Cooke Wright Memorial Lectureship. |

  12. Preventing Tragedy.

    ERIC Educational Resources Information Center

    One Feather, Sandra

    2003-01-01

    The Navajo supervisor in the Office of Environmental Health in New Mexico identifies diseases and their risk factors, administers an injury prevention program, and ensures compliance with various health-related codes. She assists in the planning and direction of environmental health programs and public health education for local Navajo…

  13. Bullying Prevention

    ERIC Educational Resources Information Center

    Kemp, Patrice

    2016-01-01

    The focus of the milestone project is to focus on bridging the gap of bullying and classroom instruction methods. There has to be a defined expectations and level of accountability that has to be defined when supporting and implementing a plan linked to bullying prevention. All individuals involved in the student's learning have to be aware of…

  14. Shoplifting Prevention.

    ERIC Educational Resources Information Center

    Everhardt, Richard M.

    The retailers' concern about shoplifting and shoplifting losses provided impetus for the development of this programed text. The self-instructional booklet is designed for all retail employees as an aid to preventing financial losses to the store caused by shoplifting. The common characteristics of shoplifters, methods used by shoplifters, and a…

  15. Stereotype threat can reduce older adults' memory errors.

    PubMed

    Barber, Sarah J; Mather, Mara

    2013-01-01

    Stereotype threat often incurs the cost of reducing the amount of information that older adults accurately recall. In the current research, we tested whether stereotype threat can also benefit memory. According to the regulatory focus account of stereotype threat, threat induces a prevention focus in which people become concerned with avoiding errors of commission and are sensitive to the presence or absence of losses within their environment. Because of this, we predicted that stereotype threat might reduce older adults' memory errors. Results were consistent with this prediction. Older adults under stereotype threat had lower intrusion rates during free-recall tests (Experiments 1 and 2). They also reduced their false alarms and adopted more conservative response criteria during a recognition test (Experiment 2). Thus, stereotype threat can decrease older adults' false memories, albeit at the cost of fewer veridical memories, as well.

  16. Neurocognitive architecture of working memory

    PubMed Central

    Eriksson, Johan; Vogel, Edward K.; Lansner, Anders; Bergström, Fredrik; Nyberg, Lars

    2015-01-01

    The crucial role of working memory for temporary information processing and guidance of complex behavior has been recognized for many decades. There is emerging consensus that working memory maintenance results from the interactions among long-term memory representations and basic processes, including attention, that are instantiated as reentrant loops between frontal and posterior cortical areas, as well as subcortical structures. The nature of such interactions can account for capacity limitations, lifespan changes, and restricted transfer after working-memory training. Recent data and models indicate that working memory may also be based on synaptic plasticity, and that working memory can operate on non-consciously perceived information. PMID:26447571

  17. Memory function and supportive technology

    PubMed Central

    Charness, Neil; Best, Ryan; Souders, Dustin

    2013-01-01

    Episodic and working memory processes show pronounced age-related decline, with other memory processes such as semantic, procedural, and metamemory less affected. Older adults tend to complain the most about prospective and retrospective memory failures. We introduce a framework for deciding how to mitigate memory decline using augmentation and substitution and discuss techniques that change the user, through mnemonics training, and change the tool or environment, by providing environmental support. We provide examples of low-tech and high-tech memory supports and discuss constraints on the utility of high-tech systems including effectiveness of devices, attitudes toward memory aids, and reliability of systems. PMID:24379752

  18. Nanoporous silicon oxide memory.

    PubMed

    Wang, Gunuk; Yang, Yang; Lee, Jae-Hwang; Abramova, Vera; Fei, Huilong; Ruan, Gedeng; Thomas, Edwin L; Tour, James M

    2014-08-13

    Oxide-based two-terminal resistive random access memory (RRAM) is considered one of the most promising candidates for next-generation nonvolatile memory. We introduce here a new RRAM memory structure employing a nanoporous (NP) silicon oxide (SiOx) material which enables unipolar switching through its internal vertical nanogap. Through the control of the stochastic filament formation at low voltage, the NP SiOx memory exhibited an extremely low electroforming voltage (∼ 1.6 V) and outstanding performance metrics. These include multibit storage ability (up to 9-bits), a high ON-OFF ratio (up to 10(7) A), a long high-temperature lifetime (≥ 10(4) s at 100 °C), excellent cycling endurance (≥ 10(5)), sub-50 ns switching speeds, and low power consumption (∼ 6 × 10(-5) W/bit). Also provided is the room temperature processability for versatile fabrication without any compliance current being needed during electroforming or switching operations. Taken together, these metrics in NP SiOx RRAM provide a route toward easily accessed nonvolatile memory applications.

  19. Vertical bloch line memory

    NASA Technical Reports Server (NTRS)

    Katti, Romney R. (Inventor); Stadler, Henry L. (Inventor); Wu, Jiin-chuan (Inventor)

    1995-01-01

    A new read gate design for the vertical Bloch line (VBL) memory is disclosed which offers larger operating margin than the existing read gate designs. In the existing read gate designs, a current is applied to all the stripes. The stripes that contain a VBL pair are chopped, while the stripes that do not contain a VBL pair are not chopped. The information is then detected by inspecting the presence or absence of the bubble. The margin of the chopping current amplitude is very small, and sometimes non-existent. A new method of reading Vertical Bloch Line memory is also disclosed. Instead of using the wall chirality to separate the two binary states, the spatial deflection of the stripe head is used. Also disclosed herein is a compact memory which uses vertical Bloch line (VBL) memory technology for providing data storage. A three-dimensional arrangement in the form of stacks of VBL memory layers is used to achieve high volumetric storage density. High data transfer rate is achieved by operating all the layers in parallel. Using Hall effect sensing, and optical sensing via the Faraday effect to access the data from within the three-dimensional packages, an even higher data transfer rate can be achieved due to parallel operation within each layer.

  20. Tianeptine: an antidepressant with memory-protective properties.

    PubMed

    Zoladz, Phillip R; Park, Collin R; Muñoz, Carmen; Fleshner, Monika; Diamond, David M

    2008-12-01

    The development of effective pharmacotherapy for major depression is important because it is such a widespread and debilitating mental disorder. Here, we have reviewed preclinical and clinical studies on tianeptine, an atypical antidepressant which ameliorates the adverse effects of stress on brain and memory. In animal studies, tianeptine has been shown to prevent stress-induced morphological sequelae in the hippocampus and amygdala, as well as to prevent stress from impairing synaptic plasticity in the prefrontal cortex and hippocampus. Tianeptine also has memory-protective characteristics, as it blocks the adverse effects of stress on hippocampus-dependent learning and memory. We have further extended the findings on stress, memory and tianeptine here with two novel observations: 1) stress impairs spatial memory in adrenalectomized (ADX), thereby corticosterone-depleted, rats; and 2) the stress-induced impairment of memory in ADX rats is blocked by tianeptine. These findings are consistent with previous research which indicates that tianeptine produces anti-stress and memory-protective properties without altering the response of the hypothalamic-pituitary-adrenal axis to stress. We conclude with a discussion of findings which indicate that tianeptine accomplishes its anti-stress effects by normalizing stress-induced increases in glutamate in the hippocampus and amygdala. This finding is potentially relevant to recent research which indicates that abnormalities in glutamatergic neurotransmission are involved in the pathogenesis of depression. Ultimately, tianeptine's prevention of depression-induced sequelae in the brain is likely to be a primary factor in its effectiveness as a pharmacological treatment for depression.

  1. MEMORIAL WALK WITH MEMORIALS, TOWARD ENTRANCE GATE. VIEW TO WEST. ...

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

    MEMORIAL WALK WITH MEMORIALS, TOWARD ENTRANCE GATE. VIEW TO WEST. - Rock Island National Cemetery, Rock Island Arsenal, 0.25 mile north of southern tip of Rock Island, Rock Island, Rock Island County, IL

  2. Repeatedly Reactivated Memories Become More Resistant to Hippocampal Damage

    ERIC Educational Resources Information Center

    Lehmann, Hugo; McNamara, Kathryn C.

    2011-01-01

    We examined whether repeated reactivations of a context memory would prevent the typical amnesic effects of post-training damage to the hippocampus (HPC). Rats were given a single contextual fear-conditioning session followed by 10 reactivations, involving a brief return to the conditioning context (no shock). Subsequently, the rats received sham…

  3. Perirhinal Cortex Muscarinic Receptor Blockade Impairs Taste Recognition Memory Formation

    ERIC Educational Resources Information Center

    Gutierrez, Ranier; De la Cruz, Vanesa; Rodriguez-Ortiz, Carlos J.; Bermudez-Rattoni, Federico

    2004-01-01

    The relevance of perirhinal cortical cholinergic and glutamatergic neurotransmission for taste recognition memory and learned taste aversion was assessed by microinfusions of muscarinic (scopolamine), NMDA (AP-5), and AMPA (NBQX) receptor antagonists. Infusions of scopolamine, but not AP5 or NBQX, prevented the consolidation of taste recognition…

  4. Bergson's "Matter and Memory" and modern selectionist theories of memory.

    PubMed

    McNamara, P

    1996-03-01

    Bergson's reflections (in Matter and Memory, 1896) on memory anticipated development of modern selectionist theories of memory. Selectionist models offer new and potentially useful approaches to a theory of remembering. On the model of natural selection, these selectionist theories require at least two processing components: a device which generates a range of memory representations and a selection process which preserves a subset of those representations. Bergson shows how the subjective experience of remembering might be understood within a selectionist framework.

  5. Emotion and autobiographical memory

    NASA Astrophysics Data System (ADS)

    Holland, Alisha C.; Kensinger, Elizabeth A.

    2010-03-01

    Autobiographical memory encompasses our recollections of specific, personal events. In this article, we review the interactions between emotion and autobiographical memory, focusing on two broad ways in which these interactions occur. First, the emotional content of an experience can influence the way in which the event is remembered. Second, emotions and emotional goals experienced at the time of autobiographical retrieval can influence the information recalled. We discuss the behavioral manifestations of each of these types of interactions and describe the neural mechanisms that may support those interactions. We discuss how findings from the clinical literature (e.g., regarding depression) and the social psychology literature (e.g., on emotion regulation) might inform future investigations of the interplay between the emotions experienced at the time of retrieval and the memories recalled, and we present ideas for future research in this domain.

  6. Echoic memory in pigeons.

    PubMed

    Kretzschmar, Christina; Kalenscher, Tobias; Güntürkün, Onur; Kaernbach, Christian

    2008-10-01

    It is unknown whether birds are able to retain the memory of purely sensory auditory information such as white noise over an extended period of time. In a Pavlovian heart rate conditioning paradigm, four pigeons were trained to associate a mild electric shock with periodic random waveforms, and no shock with aperiodic noise. Periodic waveform detection requires echoic memory, i.e., the online retention of a waveform pattern over a limited time. Starting with 40ms, the waveform period was increased after successful learning until no significant stimulus discrimination could be found. Significant discrimination was achieved at periods of up to 2560ms. This is the first demonstration that echoic memory performance in birds is clearly superior to cats and gerbils, and comparable to naive human performance.

  7. Emotion and Autobiographical Memory

    PubMed Central

    Holland, Alisha C.; Kensinger, Elizabeth A.

    2010-01-01

    Autobiographical memory encompasses our recollections of specific, personal events. In this article, we review the interactions between emotion and autobiographical memory, focusing on two broad ways in which these interactions occur. First, the emotional content of an experience can influence the way in which the event is remembered. Second, emotions and emotional goals experienced at the time of autobiographical retrieval can influence the information recalled. We discuss the behavioral manifestations of each of these types of interactions and describe the neural mechanisms that may support those interactions. We discuss how findings from the clinical literature (e.g., regarding depression) and the social psychology literature (e.g., on emotion regulation) might inform future investigations of the interplay between the emotions experienced at the time of retrieval and the memories recalled, and we present ideas for future research in this domain. PMID:20374933

  8. Amygdala Dopamine Receptors Are Required for the Destabilization of a Reconsolidating Appetitive Memory(1,2).

    PubMed

    Merlo, Emiliano; Ratano, Patrizia; Ilioi, Elena C; Robbins, Miranda A L S; Everitt, Barry J; Milton, Amy L

    2015-01-01

    Disrupting maladaptive memories may provide a novel form of treatment for neuropsychiatric disorders, but little is known about the neurochemical mechanisms underlying the induction of lability, or destabilization, of a retrieved consolidated memory. Destabilization has been theoretically linked to the violation of expectations during memory retrieval, which, in turn, has been suggested to correlate with prediction error (PE). It is well-established that PE correlates with dopaminergic signaling in limbic forebrain structures that are critical for emotional learning. The basolateral amygdala is a key neural substrate for the reconsolidation of pavlovian reward-related memories, but the involvement of dopaminergic mechanisms in inducing lability of amygdala-dependent memories has not been investigated. Therefore, we tested the hypothesis that dopaminergic signaling within the basolateral amygdala is required for the destabilization of appetitive pavlovian memories by investigating the effects dopaminergic and protein synthesis manipulations on appetitive memory reconsolidation in rats. Intra-amygdala administration of either the D1-selective dopamine receptor antagonist SCH23390 or the D2-selective dopamine receptor antagonist raclopride prevented memory destabilization at retrieval, thereby protecting the memory from the effects of an amnestic agent, the protein synthesis inhibitor anisomycin. These data show that dopaminergic transmission within the basolateral amygdala is required for memory labilization during appetitive memory reconsolidation.

  9. Occupational Memory Practice and Memory Beliefs with Age

    ERIC Educational Resources Information Center

    Huet, Nathalie; Marquie, Jean-Claude; Bacon, Elisabeth

    2010-01-01

    This study examined effects of intensive memory use during one's profession on metamemory beliefs. Fifty-one actors and 60 controls aged from 20 to 73 years were compared with the Metamemory Inventory in Adulthood. Both intensive job-related memory practice and younger age were associated with stronger memory self-efficacy beliefs. Irrespective of…

  10. Negative Affect Impairs Associative Memory but Not Item Memory

    ERIC Educational Resources Information Center

    Bisby, James A.; Burgess, Neil

    2014-01-01

    The formation of associations between items and their context has been proposed to rely on mechanisms distinct from those supporting memory for a single item. Although emotional experiences can profoundly affect memory, our understanding of how it interacts with different aspects of memory remains unclear. We performed three experiments to examine…

  11. An overview of advanced nonvolatile memory technologies

    SciTech Connect

    Dressendorfer, P.V.

    1991-01-01

    This report is an overview of advanced nonvolatile memory technologies. The memory technologies discussed are: floating gate nonvolatile memory technologies; SNOS nonvolatile technology; ferroelectric technology; and thin film magnetic memories.

  12. Dreams, conscience, and memory.

    PubMed

    Stein, M H

    1991-04-01

    The interpretation of certain dreams, as opposed to the direct examination of behavior, makes it possible to explore the conscience of the dreamer, detect hidden sources of guilt, and interpret them with less likelihood of arousing intractable resistance. Through the recovery of memories and the establishment of an intimate familiarity with one's personal history, it becomes possible to resolve problems of "neurotic" guilt, based ultimately on distortions of repressed childhood memories. The resolution of these conflicts allows a greater role for the operation of "appropriate" guilt, based on genuine transgressions, and the establishment of a more mature ethical structure.

  13. Natural Killer Cell Memory.

    PubMed

    O'Sullivan, Timothy E; Sun, Joseph C; Lanier, Lewis L

    2015-10-20

    Natural killer (NK) cells have historically been considered short-lived cytolytic cells that can rapidly respond against pathogens and tumors in an antigen-independent manner and then undergo cell death. Recently, however, NK cells have been shown to possess traits of adaptive immunity and can acquire immunological memory in a manner similar to that of T and B cells. In this review, we discuss evidence of NK cell memory and the mechanisms involved in the generation and survival of these innate lymphocytes.

  14. Preeclampsia prevention

    PubMed Central

    Herrera-Medina, Rodolfo; Pineda, Lucia M

    2015-01-01

    Background: Preeclampsia is the main complication of pregnancy in developing countries. Calcium starting at 14 weeks of pregnancy is indicated to prevent the disease. Recent advances in prevention of preeclampsia endorse the addition of conjugated linoleic acid. Objective: To estimate the protective effect from calcium alone, compared to calcium plus conjugated linoleic acid in nulliparous women at risk of preeclampsia. Methods: A case-control design nested in the cohort of nulliparous women attending antenatal care from 2010 to 2014. The clinical histories of 387 cases of preeclampsia were compared with 1,054 normotensive controls. The exposure was prescriptions for calcium alone, the first period, or calcium plus conjugated linoleic acid, the second period, from 12 to 16 weeks of gestational age to labor. Confounding variables were controlled, allowing only nulliparous women into the study and stratifying by age, education and ethnic group. Results: The average age was 26.4 yrs old (range= 13-45), 85% from mixed ethnic backgrounds and with high school education. There were no differences between women who received calcium carbonate and those who did not (OR= 0.96; 95% CI= 0.73-1.27). The group of adolescents (13 to 18 years old) in the calcium plus conjugated linoleic acid was protected for preeclampsia (OR= 0.00; 95% CI= 0.00-0.44) independent of the confounder variables. Conclusions: 1. Calcium supplementation during pregnancy did not have preventive effects on preeclampsia. 2. Calcium plus Conjugated Linoleic acid provided to adolescents was observed to have preventive effect on Preeclampsia. PMID:26848195

  15. Memory and Forgetfulness: NIH Research

    MedlinePlus

    ... of this page please turn Javascript on. Feature: Memory & Forgetfulness NIH Research Past Issues / Summer 2013 Table ... agency for research on Alzheimer's disease and related memory research. An analysis funded by the NIA finds ...

  16. Shape memory polymer medical device

    DOEpatents

    Maitland, Duncan; Benett, William J.; Bearinger, Jane P.; Wilson, Thomas S.; Small, IV, Ward; Schumann, Daniel L.; Jensen, Wayne A.; Ortega, Jason M.; Marion, III, John E.; Loge, Jeffrey M.

    2010-06-29

    A system for removing matter from a conduit. The system includes the steps of passing a transport vehicle and a shape memory polymer material through the conduit, transmitting energy to the shape memory polymer material for moving the shape memory polymer material from a first shape to a second and different shape, and withdrawing the transport vehicle and the shape memory polymer material through the conduit carrying the matter.

  17. Play Memories and Place Identity.

    ERIC Educational Resources Information Center

    Sandberg, Anette

    2003-01-01

    This retrospective study examined play memories from childhood to adulthood of 478 university students between ages 20 and 62 as exhibited in drawings of play memories and questionnaire responses. The study focused on the role of the physical environment and place identity in play memories and individual identity development. Findings showed that…

  18. Origins of Adolescents' Autobiographical Memories

    ERIC Educational Resources Information Center

    Reese, Elaine; Jack, Fiona; White, Naomi

    2010-01-01

    Adolescents (N = 46; M = 12.46 years) who had previously participated in a longitudinal study of autobiographical memory development narrated their early childhood memories, interpreted life events, and completed a family history questionnaire and language assessment. Three distinct components of adolescent memory emerged: (1) age of earliest…

  19. First Words and First Memories

    ERIC Educational Resources Information Center

    Morrison, Catriona M.; Conway, Martin A.

    2010-01-01

    In two experiments autobiographical memories from childhood were recalled to cue words naming common objects, locations, activities and emotions. Participants recalled their earliest specific memory associated with each word and dated their age at the time of the remembered event. A striking and specific finding emerged: age of earliest memory was…

  20. Dual redundant core memory systems

    NASA Technical Reports Server (NTRS)

    Hull, F. E.

    1972-01-01

    Electronic memory system consisting of series redundant drive switch circuits, triple redundant majority voted memory timing functions, and two data registers to provide functional dual redundancy is described. Signal flow through the circuits is illustrated and equence of events which occur within the memory system is explained.

  1. Windows Memory Forensic Data Visualization

    DTIC Science & Technology

    2014-06-12

    WINDOWS MEMORY FORENSIC DATA VISUALIZATION THESIS J. Brendan Baum, Civilian, USAF AFIT...WINDOWS MEMORY FORENSIC DATA VISUALIZATION THESIS Presented to the Faculty Department of Electrical and Computer Engineering Graduate School of...APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED AFIT-ENG-T-14-J-1 WINDOWS MEMORY FORENSIC DATA VISUALIZATION J. Brendan Baum, B.S

  2. Stroke and Episodic Memory Disorders

    ERIC Educational Resources Information Center

    Lim, Chun; Alexander, Michael P.

    2009-01-01

    Memory impairments are common after stroke, and the anatomical basis for impairments may be quite variable. To determine the range of stroke-related memory impairment, we identified all case reports and group studies through the Medline database and the Science Citation Index. There is no hypothesis about memory that is unique to stroke, but there…

  3. Memory Storage and Neural Systems.

    ERIC Educational Resources Information Center

    Alkon, Daniel L.

    1989-01-01

    Investigates memory storage and molecular nature of associative-memory formation by analyzing Pavlovian conditioning in marine snails and rabbits. Presented is the design of a computer-based memory system (neural networks) using the rules acquired in the investigation. Reports that the artificial network recognized patterns well. (YP)

  4. Stress disrupts response memory retrieval.

    PubMed

    Guenzel, Friederike M; Wolf, Oliver T; Schwabe, Lars

    2013-08-01

    Stress effects on memory are well-known. Most studies, however, focused on the impact of stress on hippocampus-dependent 'declarative' memory processes. Less is known about whether stress influences also striatum-based memory processes, such as stimulus-response (S-R) memory. First evidence from rodent experiments shows that glucocorticoid stress hormones may enhance the consolidation of S-R memories. Whether stress affects also S-R memory retrieval remains largely elusive. Therefore, we tested in the present experiment in humans the effect of stress on the retrieval of S-R memories. Healthy men and women were trained to locate three objects in an S-R version of a virtual eight-arm radial maze. One week later, participants underwent a stressor or a control condition before their memory of the S-R task was tested. Our results showed that participants (n=43) who were exposed to the stressor before retention testing made significantly more errors in this test trial, suggesting that stress impaired S-R memory retrieval. Moreover, high cortisol concentrations were associated with reduced S-R memory. These findings indicate that stress may affect memory retrieval processes in humans beyond hippocampal 'declarative' memory.

  5. Memory Processes in Media Effects.

    ERIC Educational Resources Information Center

    Kellermann, Kathy

    1985-01-01

    Explores the role of memory in mediating mass communication effects. Examines (1) the nature of memory, (2) issues in retention and recall of media messages, (3) methods of promoting retention and recall of media messages, and (4) implications of memory processes for mass media effects. (PD)

  6. Motor Action and Emotional Memory

    ERIC Educational Resources Information Center

    Casasanto, Daniel; Dijkstra, Katinka

    2010-01-01

    Can simple motor actions affect how efficiently people retrieve emotional memories, and influence what they choose to remember? In Experiment 1, participants were prompted to retell autobiographical memories with either positive or negative valence, while moving marbles either upward or downward. They retrieved memories faster when the direction…

  7. The contribution of epigenetic memory to immunologic memory.

    PubMed

    Zediak, Valerie P; Wherry, E John; Berger, Shelley L

    2011-04-01

    Memory T lymphocytes are distinct from antigen-inexperienced naïve T cells in that memory T cells can respond more rapidly when they re-encounter a pathogen. Work over the past decade has begun to define the epigenetic underpinnings of the transcriptional component of the memory T cell response. An emerging theme is the persistence of an active chromatin signature at relevant gene loci in resting memory T cells, even when those genes are transcriptionally inactive. This gives strength to the concept of gene poising, and has shown that memory T lymphocytes are an ideal model in which to further define various mechanisms of epigenetic poising.

  8. Memory retrieval requires ongoing protein synthesis and NMDA receptor activity-mediated AMPA receptor trafficking.

    PubMed

    Lopez, Joëlle; Gamache, Karine; Schneider, Rilla; Nader, Karim

    2015-02-11

    Whereas consolidation and reconsolidation are considered dynamic processes requiring protein synthesis, memory retrieval has long been considered a passive readout of previously established plasticity. However, previous findings suggest that memory retrieval may be more dynamic than previously thought. This study therefore aimed at investigating the molecular mechanisms underlying memory retrieval in the rat. Infusion of protein synthesis inhibitors (rapamycin or anisomycin) in the amygdala 10 min before memory retrieval transiently impaired auditory fear memory expression, suggesting ongoing protein synthesis is required to enable memory retrieval. We then investigated the role of protein synthesis in NMDA receptor activity-mediated AMPA receptor trafficking. Coinfusion of an NMDA receptor antagonist (ifenprodil) or infusion of an AMPA receptor endocytosis inhibitor (GluA23Y) before rapamycin prevented this memory impairment. Furthermore, rapamycin transiently decreased GluA1 levels at the postsynaptic density (PSD), but did not affect extrasynaptic sites. This effect at the PSD was prevented by an infusion of GluA23Y before rapamycin. Together, these data show that ongoing protein synthesis is required before memory retrieval is engaged, and suggest that this protein synthesis may be involved in the NMDAR activity-mediated trafficking of AMPA receptors that takes place during memory retrieval.

  9. Judgments of Associative Memory

    ERIC Educational Resources Information Center

    Maki, William S.

    2007-01-01

    Judgments of associative memory (JAM) were indexed by ratings given to pairs of cue and response words. The normed probabilities, p(response|cue), were obtained from free association norms. The ratings were linearly related to the probabilities. The JAM functions were characterized by high intercepts (approximately 50 on a 100 point scale) and…

  10. When Autobiographical Memory Begins

    ERIC Educational Resources Information Center

    Howe, Mark L.; Courage, Mary L.; Edison, Shannon C.

    2003-01-01

    The authors review competing theories concerning the emergence and early development of autobiographical memory. It is argued that the differences between these accounts, although important, may be more apparent than real. The crux of these disagreements lies not in "what" processes are important, but rather, the role these different processes…

  11. Shape Memory Alloy Actuator

    NASA Technical Reports Server (NTRS)

    Baumbick, Robert J. (Inventor)

    2002-01-01

    The present invention discloses and teaches a unique, remote optically controlled micro actuator particularly suitable for aerospace vehicle applications wherein hot gas, or in the alternative optical energy, is employed as the medium by which shape memory alloy elements are activated. In gas turbine powered aircraft the source of the hot gas may be the turbine engine compressor or turbine sections.

  12. Shape Memory Alloy Actuator

    NASA Technical Reports Server (NTRS)

    Baumbick, Robert J. (Inventor)

    2000-01-01

    The present invention discloses and teaches a unique, remote optically controlled micro actuator particularly suitable for aerospace vehicle applications wherein hot gas, or in the alternative optical energy, is employed as the medium by which shape memory alloy elements are activated. In gas turbine powered aircraft the source of the hot gas may be the turbine engine compressor or turbine sections.

  13. Dreams Memories & Photography

    ERIC Educational Resources Information Center

    Young, Bernard

    2012-01-01

    Photography students spend a considerable amount of time working on technical issues in shooting, composing, editing, and processing prints. Another aspect of their learning should include the conception and communication of their ideas. A student's memories and dreams can serve as motivation to create images in visual art. Some artists claim that…

  14. Antenatal memories and psychopathology

    PubMed Central

    Neighbour, Roger

    1981-01-01

    A case is described of suicidal impulses apparently stemming from the patient's experience before and during his birth. By using a technique of `rebirthing', antenatal memories were relived and their traumatic effects resolved. Theoretical and practical accounts of rebirthing are given, and its significance for general practitioners is discussed. PMID:7338871

  15. Memorials: Art for Remembering.

    ERIC Educational Resources Information Center

    Art to Zoo: Teaching With the Power of Objects, 1995

    1995-01-01

    Throughout history, in all parts of the world, people have struggled with the problem of loss. Moving words have been written and beautiful objects created to preserve the memory of people and their achievements. This theme issue explores the different ways that people have been praised and remembered in works of art. An introduction suggests a…

  16. Memory Mechanisms in Grasping

    ERIC Educational Resources Information Center

    Hesse, Constanze; Franz, Volker H.

    2009-01-01

    The availability of visual information influences the execution of goal-directed movements. This is very prominent in memory conditions, where a delay is introduced between stimulus presentation and execution of the movement. The corresponding effects could be due to a decay of the visual information or to different processing mechanisms used for…

  17. The Grammar of Memory

    ERIC Educational Resources Information Center

    Sawyer, Wayne

    2016-01-01

    This essay focuses on two sites of memory in my professional life. One is from my very early years of teaching, the second from about 10 years later. Each is centred on a moment of controversy in English curriculum in New South Wales, Australia, and each is to do with the teaching of writing and the supposed neglect of language study, including…

  18. A Balanced Memory Network

    PubMed Central

    Roudi, Yasser; Latham, Peter E

    2007-01-01

    A fundamental problem in neuroscience is understanding how working memory—the ability to store information at intermediate timescales, like tens of seconds—is implemented in realistic neuronal networks. The most likely candidate mechanism is the attractor network, and a great deal of effort has gone toward investigating it theoretically. Yet, despite almost a quarter century of intense work, attractor networks are not fully understood. In particular, there are still two unanswered questions. First, how is it that attractor networks exhibit irregular firing, as is observed experimentally during working memory tasks? And second, how many memories can be stored under biologically realistic conditions? Here we answer both questions by studying an attractor neural network in which inhibition and excitation balance each other. Using mean-field analysis, we derive a three-variable description of attractor networks. From this description it follows that irregular firing can exist only if the number of neurons involved in a memory is large. The same mean-field analysis also shows that the number of memories that can be stored in a network scales with the number of excitatory connections, a result that has been suggested for simple models but never shown for realistic ones. Both of these predictions are verified using simulations with large networks of spiking neurons. PMID:17845070

  19. Memory Loss and Retrieval

    ERIC Educational Resources Information Center

    Reid, Ian

    2016-01-01

    Underlying the generally oblivious attitude of teachers and learners towards the past is insufficient respect for the role of memory in giving meaning to experience and access to knowledge. We shape our identity by making sense of our past and its relationship to present and future selves, a process that should be intensively cultivated when we…

  20. Radiation Tolerant Embedded Memory

    DTIC Science & Technology

    2007-11-02

    REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 ...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1 . REPORT DATE (DD-MM-YYYY) 27-06-2003 2. REPORT TYPE SBIR...Tolerant Embedded Memory 1 Table of Contents: Table of Contents

  1. Bubble Memory Module.

    DTIC Science & Technology

    1980-12-01

    104 7-13 Four switch drive hybrid ........................................................................ 104 7-14...operation. Address Ready. - This signal is an output signal to the user which acknowledges that the module is busy. Input address is latched in the...expandable in 6.55 M bit increments. Detector noise is minimized by locating sense circuits, cell select switches , and memory cells on the same board

  2. The role of stress during memory reactivation on intrusive memories.

    PubMed

    Cheung, Jessica; Garber, Benjamin; Bryant, Richard A

    2015-09-01

    Intrusive memories are unwanted recollections that maintain distress in psychological disorders. Increasing evidence suggests that memories that are reactivated through retrieval become temporarily vulnerable to environmental or pharmacological manipulation, including changes in levels of circulating stress hormones. This study investigated the influence of stress during memory reactivation of an emotionally arousing trauma film on subsequent intrusive memories. Three groups of participants (N=63) viewed a trauma film depicting a serious car accident at baseline. Two days later (Time 2), one group received a reactivation induction following a socially evaluated cold pressor test (SECPT; Stress/Reactivation condition), whilst the second group reactivated the memory after a control procedure (Reactivation condition). A third group underwent the SECPT but was not asked to reactivate memory of the trauma film (Stress condition). Two days later (Time 3), all participants received a surprise cued memory recall test and intrusions questionnaire which they completed online. Results showed that those in the Stress/Reactivation group had higher intrusions scores than the other two groups, suggesting that acute stress promotes intrusive memories only when the memory trace is reactivated shortly afterwards. Increased cortisol predicted enhanced intrusive experiences in the Stress/Reactivation condition but not in the other conditions. This pattern of results suggests that acute stress during the reactivation of emotional material impacts on involuntary emotional memories. These findings suggest a possible explanation for the mechanism underlying the maintenance of intrusive memories in clinical disorders.

  3. False memories in highly superior autobiographical memory individuals

    PubMed Central

    Patihis, Lawrence; Frenda, Steven J.; LePort, Aurora K. R.; Petersen, Nicole; Nichols, Rebecca M.; Stark, Craig E. L.; McGaugh, James L.; Loftus, Elizabeth F.

    2013-01-01

    The recent identification of highly superior autobiographical memory (HSAM) raised the possibility that there may be individuals who are immune to memory distortions. We measured HSAM participants’ and age- and sex-matched controls’ susceptibility to false memories using several research paradigms. HSAM participants and controls were both susceptible to false recognition of nonpresented critical lure words in an associative word-list task. In a misinformation task, HSAM participants showed higher overall false memory compared with that of controls for details in a photographic slideshow. HSAM participants were equally as likely as controls to mistakenly report they had seen nonexistent footage of a plane crash. Finding false memories in a superior-memory group suggests that malleable reconstructive mechanisms may be fundamental to episodic remembering. Paradoxically, HSAM individuals may retrieve abundant and accurate autobiographical memories using fallible reconstructive processes. PMID:24248358

  4. False memories in highly superior autobiographical memory individuals.

    PubMed

    Patihis, Lawrence; Frenda, Steven J; LePort, Aurora K R; Petersen, Nicole; Nichols, Rebecca M; Stark, Craig E L; McGaugh, James L; Loftus, Elizabeth F

    2013-12-24

    The recent identification of highly superior autobiographical memory (HSAM) raised the possibility that there may be individuals who are immune to memory distortions. We measured HSAM participants' and age- and sex-matched controls' susceptibility to false memories using several research paradigms. HSAM participants and controls were both susceptible to false recognition of nonpresented critical lure words in an associative word-list task. In a misinformation task, HSAM participants showed higher overall false memory compared with that of controls for details in a photographic slideshow. HSAM participants were equally as likely as controls to mistakenly report they had seen nonexistent footage of a plane crash. Finding false memories in a superior-memory group suggests that malleable reconstructive mechanisms may be fundamental to episodic remembering. Paradoxically, HSAM individuals may retrieve abundant and accurate autobiographical memories using fallible reconstructive processes.

  5. Allergy prevention.

    PubMed

    Muche-Borowski, Cathleen; Kopp, Matthias; Reese, Imke; Sitter, Helmut; Werfel, Thomas; Schäfer, Torsten

    2010-09-01

    The further increase of allergies in industrialized countries demands evidence-based measures of primary prevention. The recommendations as published in the guideline of 2004 were updated and consented on the basis of a systematic literature search. Evidence from the period February 2003-May 2008 was searched in the electronic databases Cochrane and MEDLINE as well as in reference lists of recent reviews and by contacting experts. The retrieved citations were screened for relevance first by title and abstract and in a second step as full paper. Levels of evidence were assigned to each included study and the methodological quality of the studies was assessed as high or low. Finally the revised recommendations were formally consented (nominal group process) by representatives of relevant societies and organizations including a self-help group. Of originally 4556 hits, 217 studies (4 Cochrane Reviews, 14 meta-analyses, 19 randomized controlled trials, 135 cohort and 45 case-control studies) were included and critically appraised. Grossly unchanged remained the recommendations on avoiding environmental tobacco smoke, breast-feeding over 4 months (alternatively hypoallergenic formulas for children at risk), avoiding a mold-promoting indoor climate, vaccination according to current recommendations, and avoidance of furry pets (especially cats) in children at risk. The recommendation on reducing the house dust mite allergen exposure as a measure of primary prevention was omitted and the impact of a delayed introduction of supplementary food was reduced. New recommendations were adopted concerning fish consumption (during pregnancy / breast-feeding and as supplementary food in the first year), avoidance of overweight, and reducing the exposure to indoor and outdoor air pollutants. The revision of this guideline on a profound evidence basis led to (1) a confirmation of existing recommendations, (2) substantial revisions, and (3) new recommendations. Thereby it is possible

  6. About Sleep's Role in Memory

    PubMed Central

    2013-01-01

    Over more than a century of research has established the fact that sleep benefits the retention of memory. In this review we aim to comprehensively cover the field of “sleep and memory” research by providing a historical perspective on concepts and a discussion of more recent key findings. Whereas initial theories posed a passive role for sleep enhancing memories by protecting them from interfering stimuli, current theories highlight an active role for sleep in which memories undergo a process of system consolidation during sleep. Whereas older research concentrated on the role of rapid-eye-movement (REM) sleep, recent work has revealed the importance of slow-wave sleep (SWS) for memory consolidation and also enlightened some of the underlying electrophysiological, neurochemical, and genetic mechanisms, as well as developmental aspects in these processes. Specifically, newer findings characterize sleep as a brain state optimizing memory consolidation, in opposition to the waking brain being optimized for encoding of memories. Consolidation originates from reactivation of recently encoded neuronal memory representations, which occur during SWS and transform respective representations for integration into long-term memory. Ensuing REM sleep may stabilize transformed memories. While elaborated with respect to hippocampus-dependent memories, the concept of an active redistribution of memory representations from networks serving as temporary store into long-term stores might hold also for non-hippocampus-dependent memory, and even for nonneuronal, i.e., immunological memories, giving rise to the idea that the offline consolidation of memory during sleep represents a principle of long-term memory formation established in quite different physiological systems. PMID:23589831

  7. Software Exploit Prevention and Remediation via Software Memory Protection

    DTIC Science & Technology

    2009-05-01

    trampolines that are necessary. Trampolines are pieces of code emitted into the fragment cache to transfer con- trol back to Strata. Most control...transfer instructions (CTIs) are initially linked to trampolines (unless the transfer target already exists in the fragment cache). Once a CTI’s target...instruction becomes available in the fragment cache, the CTI is linked directly to the destination, avoiding future uses of the trampoline . This

  8. Semax prevents learning and memory inhibition by heavy metals.

    PubMed

    Inozemtsev, A N; Bokieva, S B; Karpukhina, O V; Gumargalieva, K Z; Kamensky, A A; Myasoedov, N F

    2016-05-01

    Separate and joint effect of Semax, ascorbic acid, lead diacetate, and ammonium molybdate on avoidance conditioning in rats was studied. It was established that the heavy metal salts inhibited the avoidance response, and the peptide counteracted this inhibition as strongly as ascorbic acid or to a comparable degree. These findings confirm the antioxidant properties of Semax.

  9. Falling towards forgetfulness: synaptic decay prevents spontaneous recovery of memory.

    PubMed

    Stone, James V; Jupp, Peter E

    2008-08-22

    Long after a new language has been learned and forgotten, relearning a few words seems to trigger the recall of other words. This "free-lunch learning" (FLL) effect has been demonstrated both in humans and in neural network models. Specifically, previous work proved that linear networks that learn a set of associations, then partially forget them all, and finally relearn some of the associations, show improved performance on the remaining (i.e., nonrelearned) associations. Here, we prove that relearning forgotten associations decreases performance on nonrelearned associations; an effect we call negative free-lunch learning. The difference between free-lunch learning and the negative free-lunch learning presented here is due to the particular method used to induce forgetting. Specifically, if forgetting is induced by isotropic drifting of weight vectors (i.e., by adding isotropic noise), then free-lunch learning is observed. However, as proved here, if forgetting is induced by weight values that simply decay or fall towards zero, then negative free-lunch learning is observed. From a biological perspective, and assuming that nervous systems are analogous to the networks used here, this suggests that evolution may have selected physiological mechanisms that involve forgetting using a form of synaptic drift rather than synaptic decay, because synaptic drift, but not synaptic decay, yields free-lunch learning.

  10. Neutrophil depletion after subarachnoid hemorrhage improves memory via NMDA receptors.

    PubMed

    Provencio, Jose Javier; Swank, Valerie; Lu, Haiyan; Brunet, Sylvain; Baltan, Selva; Khapre, Rohini V; Seerapu, Himabindu; Kokiko-Cochran, Olga N; Lamb, Bruce T; Ransohoff, Richard M

    2016-05-01

    Cognitive deficits after aneurysmal subarachnoid hemorrhage (SAH) are common and disabling. Patients who experience delayed deterioration associated with vasospasm are likely to have cognitive deficits, particularly problems with executive function, verbal and spatial memory. Here, we report neurophysiological and pathological mechanisms underlying behavioral deficits in a murine model of SAH. On tests of spatial memory, animals with SAH performed worse than sham animals in the first week and one month after SAH suggesting a prolonged injury. Between three and six days after experimental hemorrhage, mice demonstrated loss of late long-term potentiation (L-LTP) due to dysfunction of the NMDA receptor. Suppression of innate immune cell activation prevents delayed vasospasm after murine SAH. We therefore explored the role of neutrophil-mediated innate inflammation on memory deficits after SAH. Depletion of neutrophils three days after SAH mitigates tissue inflammation, reverses cerebral vasoconstriction in the middle cerebral artery, and rescues L-LTP dysfunction at day 6. Spatial memory deficits in both the short and long-term are improved and associated with a shift of NMDA receptor subunit composition toward a memory sparing phenotype. This work supports further investigating suppression of innate immunity after SAH as a target for preventative therapies in SAH.

  11. The Relationships of Working Memory, Secondary Memory, and General Fluid Intelligence: Working Memory Is Special

    ERIC Educational Resources Information Center

    Shelton, Jill Talley; Elliott, Emily M.; Matthews, Russell A.; Hill, B. D.; Gouvier, Wm. Drew

    2010-01-01

    Recent efforts have been made to elucidate the commonly observed link between working memory and reasoning ability. The results have been inconsistent, with some work suggesting that the emphasis placed on retrieval from secondary memory by working memory tests is the driving force behind this association (Mogle, Lovett, Stawski, & Sliwinski,…

  12. Atomic memory access hardware implementations

    DOEpatents

    Ahn, Jung Ho; Erez, Mattan; Dally, William J

    2015-02-17

    Atomic memory access requests are handled using a variety of systems and methods. According to one example method, a data-processing circuit having an address-request generator that issues requests to a common memory implements a method of processing the requests using a memory-access intervention circuit coupled between the generator and the common memory. The method identifies a current atomic-memory access request from a plurality of memory access requests. A data set is stored that corresponds to the current atomic-memory access request in a data storage circuit within the intervention circuit. It is determined whether the current atomic-memory access request corresponds to at least one previously-stored atomic-memory access request. In response to determining correspondence, the current request is implemented by retrieving data from the common memory. The data is modified in response to the current request and at least one other access request in the memory-access intervention circuit.

  13. Sleep deprivation and false memories.

    PubMed

    Frenda, Steven J; Patihis, Lawrence; Loftus, Elizabeth F; Lewis, Holly C; Fenn, Kimberly M

    2014-09-01

    Many studies have investigated factors that affect susceptibility to false memories. However, few have investigated the role of sleep deprivation in the formation of false memories, despite overwhelming evidence that sleep deprivation impairs cognitive function. We examined the relationship between self-reported sleep duration and false memories and the effect of 24 hr of total sleep deprivation on susceptibility to false memories. We found that under certain conditions, sleep deprivation can increase the risk of developing false memories. Specifically, sleep deprivation increased false memories in a misinformation task when participants were sleep deprived during event encoding, but did not have a significant effect when the deprivation occurred after event encoding. These experiments are the first to investigate the effect of sleep deprivation on susceptibility to false memories, which can have dire consequences.

  14. Memory loss in Alzheimer's disease.

    PubMed

    Jahn, Holger

    2013-12-01

    Loss of memory is among the first symptoms reported by patients suffering from Alzheimer's disease (AD) and by their caretakers. Working memory and long-term declarative memory are affected early during the course of the disease. The individual pattern of impaired memory functions correlates with parameters of structural or functional brain integrity. AD pathology interferes with the formation of memories from the molecular level to the framework of neural networks. The investigation of AD memory loss helps to identify the involved neural structures, such as the default mode network, the influence of epigenetic and genetic factors, such as ApoE4 status, and evolutionary aspects of human cognition. Clinically, the analysis of memory assists the definition of AD subtypes, disease grading, and prognostic predictions. Despite new AD criteria that allow the earlier diagnosis of the disease by inclusion of biomarkers derived from cerebrospinal fluid or hippocampal volume analysis, neuropsychological testing remains at the core of AD diagnosis.

  15. Vector computer memory bank contention

    NASA Technical Reports Server (NTRS)

    Bailey, D. H.

    1985-01-01

    A number of vector supercomputers feature very large memories. Unfortunately the large capacity memory chips that are used in these computers are much slower than the fast central processing unit (CPU) circuitry. As a result, memory bank reservation times (in CPU ticks) are much longer than on previous generations of computers. A consequence of these long reservation times is that memory bank contention is sharply increased, resulting in significantly lowered performance rates. The phenomenon of memory bank contention in vector computers is analyzed using both a Markov chain model and a Monte Carlo simulation program. The results of this analysis indicate that future generations of supercomputers must either employ much faster memory chips or else feature very large numbers of independent memory banks.

  16. Vector computer memory bank contention

    NASA Technical Reports Server (NTRS)

    Bailey, David H.

    1987-01-01

    A number of vector supercomputers feature very large memories. Unfortunately the large capacity memory chips that are used in these computers are much slower than the fast central processing unit (CPU) circuitry. As a result, memory bank reservation times (in CPU ticks) are much longer than on previous generations of computers. A consequence of these long reservation times is that memory bank contention is sharply increased, resulting in significantly lowered performance rates. The phenomenon of memory bank contention in vector computers is analyzed using both a Markov chain model and a Monte Carlo simulation program. The results of this analysis indicate that future generations of supercomputers must either employ much faster memory chips or else feature very large numbers of independent memory banks.

  17. Intracranial recordings and human memory.

    PubMed

    Johnson, Elizabeth L; Knight, Robert T

    2015-04-01

    Recent work involving intracranial recording during human memory performance provides superb spatiotemporal resolution on mnemonic processes. These data demonstrate that the cortical regions identified in neuroimaging studies of memory fall into temporally distinct networks and the hippocampal theta activity reported in animal memory literature also plays a central role in human memory. Memory is linked to activity at multiple interacting frequencies, ranging from 1 to 500Hz. High-frequency responses and coupling between different frequencies suggest that frontal cortex activity is critical to human memory processes, as well as a potential key role for the thalamus in neocortical oscillations. Future research will inform unresolved questions in the neuroscience of human memory and guide creation of stimulation protocols to facilitate function in the damaged brain.

  18. The selective power of causality on memory errors.

    PubMed

    Marsh, Jessecae K; Kulkofsky, Sarah

    2015-01-01

    We tested the influence of causal links on the production of memory errors in a misinformation paradigm. Participants studied a set of statements about a person, which were presented as either individual statements or pairs of causally linked statements. Participants were then provided with causally plausible and causally implausible misinformation. We hypothesised that studying information connected with causal links would promote representing information in a more abstract manner. As such, we predicted that causal information would not provide an overall protection against memory errors, but rather would preferentially help in the rejection of misinformation that was causally implausible, given the learned causal links. In two experiments, we measured whether the causal linkage of information would be generally protective against all memory errors or only selectively protective against certain types of memory errors. Causal links helped participants reject implausible memory lures, but did not protect against plausible lures. Our results suggest that causal information may promote an abstract storage of information that helps prevent only specific types of memory errors.

  19. Autoradiographic study of serotonin transporter during memory formation.

    PubMed

    Tellez, Ruth; Rocha, Luisa; Castillo, Carlos; Meneses, Alfredo

    2010-09-01

    Serotonin transporter (SERT) has been associated with drugs of abuse like d-methamphetamine (METH). METH is well known to produce effects on the monoamine systems but it is unclear how METH affects SERT and memory. Here the effects of METH and the serotonin reuptake inhibitor fluoxetine (FLX) on autoshaping and novel object recognition (NOR) were investigated. Notably, both memory tasks recruit different behavioral, neural and cognitive demand. In autoshaping task a dose-response curve for METH was determined. METH (1.0mg/kg) impaired short-term memory (STM; lasting less of 90min) in NOR and impaired both STM and long-term memory (LTM; lasting 24 and 48h) in autoshaping, indicating that METH had long-lasting effects in the latter task. A comparative autoradiography study of the relationship between the binding pattern of SERT in autoshaping new untrained vs. trained treated (METH, FLX, or both) animals was made. Considering that hemispheric dominance is important for LTM, hence right vs. left hemisphere of the brain was compared. Results showed that trained animals decreased cortical SERT binding relative to untrained ones. In untrained and trained treated animals with the amnesic dose (1.0mg/kg) of METH SERT binding in several areas including hippocampus and cortex decreased, more remarkably in the trained animals. In contrast, FLX improved memory, increased SERT binding, prevented the METH amnesic effect and re-established the SERT binding. In general, memory and amnesia seemed to make SERT more vulnerable to drugs effects.

  20. Memory retrieval by activating engram cells in mouse models of early Alzheimer’s disease

    PubMed Central

    Roy, Dheeraj S.; Arons, Autumn; Mitchell, Teryn I.; Pignatelli, Michele; Ryan, Tomás J.; Tonegawa, Susumu

    2016-01-01

    Summary Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by progressive memory decline and subsequent loss of broader cognitive functions1. Memory decline in early stages of Alzheimer’s is mostly limited to episodic memory, for which the hippocampus (HPC) plays a crucial role2. However, it has been uncertain whether the observed amnesia in early stages of Alzheimer’s is due to disrupted encoding and consolidation of episodic information, or an impairment in the retrieval of stored memory information. Here we show that in transgenic mouse models of early Alzheimer’s, direct optogenetic activation of hippocampal memory engram cells results in memory retrieval despite the fact that these mice are amnesic in long-term memory tests when natural recall cues are utilized, revealing a retrieval, rather than a storage impairment. Prior to amyloid plaque deposition, the amnesia in these mice is age-dependent3–5, which correlates with a progressive reduction of spine density of hippocampal dentate gyrus (DG) engram cells. We show that optogenetic induction of long-term potentiation (LTP) at perforant path (PP) synapses of DG engram cells restores both spine density and long-term memory. We also demonstrate that an ablation of DG engram cells containing restored spine density prevents the rescue of long-term memory. Thus, selective rescue of spine density in engram cells may lead to an effective strategy for treating memory loss in early stages of Alzheimer’s disease. PMID:26982728

  1. Sleep supports cued fear extinction memory consolidation independent of circadian phase.

    PubMed

    Melo, Irene; Ehrlich, Ingrid

    2016-07-01

    Sleep promotes memory, particularly for declarative learning. However, its role in non-declarative, emotional memories is less well understood. Some studies suggest that sleep may influence fear-related memories, and thus may be an important factor determining the outcome of treatments for emotional disorders such as post-traumatic stress disorder. Here, we investigated the effect of sleep deprivation and time of day on fear extinction memory consolidation. Mice were subjected to a cued Pavlovian fear and extinction paradigm at the beginning of their resting or active phase. Immediate post-extinction learning sleep deprivation for 5h compromised extinction memory when tested 24h after learning. Context-dependent extinction memory recall was completely prevented by sleep-manipulation during the resting phase, while impairment was milder during the active phase and extinction memory retained its context-specificity. Importantly, control experiments excluded confounding factors such as differences in baseline locomotion, fear generalization and stress hormone levels. Together, our findings indicate that post-learning sleep supports cued fear extinction memory consolidation in both circadian phases. The lack of correlation between memory efficacy and sleep time suggests that extinction memory may be influenced by specific sleep events in the early consolidation period.

  2. A Byzantine resilient processor with an encoded fault-tolerant shared memory

    NASA Technical Reports Server (NTRS)

    Butler, Bryan; Harper, Richard

    1990-01-01

    The memory requirements for ultra-reliable computers are expected to increase due to future increases in mission functionality and operating-system requirements. This increase will have a negative effect on the reliability and cost of the system. Increased memory size will also reduce the ability to reintegrate a channel after a transient fault, since the time required to reintegrate a channel in a conventional fault-tolerant processor is dominated by memory realignment time. A Byzantine Resilient Fault-Tolerant Processor with Fault-Tolerant Shared Memory (FTP/FTSM) is presented as a solution to these problems. The FTSM uses an encoded memory system, which reduces the memory requirement by one-half compared to a conventional quad-FTP design. This increases the reliability and decreases the cost of the system. The realignment problem is also addressed by the FTSM. Because any single error is corrected upon a read from the FTSM, a faulty channel's corrupted memory does not need realignment before reintegration of the faulty channel. A combination of correct-on-access and background scrubbing is proposed to prevent the accumulation of transient errors in the memory. With a hardware-implemented scrubber, the scrubbing cycle time, and therefore the memory fault latency, can be upper-bounded at a small value. This technique increases the reliability of the memory system and facilitates validation of its reliability model.

  3. Computer Game Play Reduces Intrusive Memories of Experimental Trauma via Reconsolidation-Update Mechanisms.

    PubMed

    James, Ella L; Bonsall, Michael B; Hoppitt, Laura; Tunbridge, Elizabeth M; Geddes, John R; Milton, Amy L; Holmes, Emily A

    2015-08-01

    Memory of a traumatic event becomes consolidated within hours. Intrusive memories can then flash back repeatedly into the mind's eye and cause distress. We investigated whether reconsolidation-the process during which memories become malleable when recalled-can be blocked using a cognitive task and whether such an approach can reduce these unbidden intrusions. We predicted that reconsolidation of a reactivated visual memory of experimental trauma could be disrupted by engaging in a visuospatial task that would compete for visual working memory resources. We showed that intrusive memories were virtually abolished by playing the computer game Tetris following a memory-reactivation task 24 hr after initial exposure to experimental trauma. Furthermore, both memory reactivation and playing Tetris were required to reduce subsequent intrusions (Experiment 2), consistent with reconsolidation-update mechanisms. A simple, noninvasive cognitive-task procedure administered after emotional memory has already consolidated (i.e., > 24 hours after exposure to experimental trauma) may prevent the recurrence of intrusive memories of those emotional events.

  4. Assessment of Cholinergic Properties of Ashwagandha Leaf-Extract in the Amnesic Mouse Brain

    PubMed Central

    Gautam, Akash; Wadhwa, Renu; Thakur, Mahendra K.

    2016-01-01

    Background In our earlier study, we have shown the memory enhancing and scopolamine-induced amnesia recovery properties of Ashwagandha leaf extract using behavioral paradigm and expression analysis of synaptic plasticity genes. Purpose However, the exact mechanism through which Ashwagandha demonstrates these effects is still unknown. Methods In the present study, we hypothesized that the alcoholic extract of Ashwagandha leaves (i-Extract) possesses cholinergic properties, which in turn inhibit the anti-cholinergic nature of scopolamine. Therefore, the potential of i-Extract to recover from the scopolamine-induced cholinergic deficits was assessed by measuring acetylcholine (neurotransmitter) and Arc (synaptic activity-related gene) expression level in the mouse brain. Results The enzymatic activity of acetyl cholinesterase and choline acetyltransferase was assessed through colorimetric assays, and expression level of Arc protein was examined by Western blotting. Furthermore, mRNA level of these genes was examined by semi-quantitative reverse-transcriptase PCR. We observed that the treatment of i-Extract in scopolamine-induced amnesic mouse attenuates scopolamine-induced detrimental alterations in the cholinergic system. Conclusion Thus, our study provided biochemical and molecular evidence of cholinergic properties of Ashwagandha leaf extract during brain disorders associated with cholinergic dysfunction. PMID:27647956

  5. Method and apparatus for faulty memory utilization

    DOEpatents

    Cher, Chen-Yong; Andrade Costa, Carlos H.; Park, Yoonho; Rosenburg, Bryan S.; Ryu, Kyung D.

    2016-04-19

    A method for faulty memory utilization in a memory system includes: obtaining information regarding memory health status of at least one memory page in the memory system; determining an error tolerance of the memory page when the information regarding memory health status indicates that a failure is predicted to occur in an area of the memory system affecting the memory page; initiating a migration of data stored in the memory page when it is determined that the data stored in the memory page is non-error-tolerant; notifying at least one application regarding a predicted operating system failure and/or a predicted application failure when it is determined that data stored in the memory page is non-error-tolerant and cannot be migrated; and notifying at least one application regarding the memory failure predicted to occur when it is determined that data stored in the memory page is error-tolerant.

  6. Child Maltreatment and Adult Substance Abuse: The Role of Memory.

    PubMed

    Elwyn, Laura; Smith, Carolyn

    2013-01-01

    Child maltreatment is a risk factor for substance abuse in adulthood. This study examines whether memory of maltreatment is a necessary link in the path leading from prospectively measured childhood maltreatment to adult substance use problems. Official Child Protective Services reports and adult retrospective recall of childhood maltreatment were used to predict illegal drug use and alcohol problems in adulthood controlling for covariates. Memory was a necessary link in the path between prospective reports of maltreatment and alcohol problems, and an important link in the path between prospective reports and illegal drug use. Implications for prevention and treatment are discussed.

  7. Child Maltreatment and Adult Substance Abuse: The Role of Memory

    PubMed Central

    ELWYN, LAURA; SMITH, CAROLYN

    2013-01-01

    Child maltreatment is a risk factor for substance abuse in adulthood. This study examines whether memory of maltreatment is a necessary link in the path leading from prospectively measured childhood maltreatment to adult substance use problems. Official Child Protective Services reports and adult retrospective recall of childhood maltreatment were used to predict illegal drug use and alcohol problems in adulthood controlling for covariates. Memory was a necessary link in the path between prospective reports of maltreatment and alcohol problems, and an important link in the path between prospective reports and illegal drug use. Implications for prevention and treatment are discussed. PMID:24319347

  8. Making Physical Activity Accessible to Older Adults with Memory Loss: A Feasibility Study

    ERIC Educational Resources Information Center

    Logsdon, Rebecca G.; McCurry, Susan M.; Pike, Kenneth C.; Teri, Linda

    2009-01-01

    Purpose: For individuals with mild cognitive impairment (MCI), memory loss may prevent successful engagement in exercise, a key factor in preventing additional disability. The Resources and Activities for Life Long Independence (RALLI) program uses behavioral principles to make exercise more accessible for these individuals. Exercises are broken…

  9. Content addressable memory project

    NASA Technical Reports Server (NTRS)

    Hall, Josh; Levy, Saul; Smith, D.; Wei, S.; Miyake, K.; Murdocca, M.

    1991-01-01

    The progress on the Rutgers CAM (Content Addressable Memory) Project is described. The overall design of the system is completed at the architectural level and described. The machine is composed of two kinds of cells: (1) the CAM cells which include both memory and processor, and support local processing within each cell; and (2) the tree cells, which have smaller instruction set, and provide global processing over the CAM cells. A parameterized design of the basic CAM cell is completed. Progress was made on the final specification of the CPS. The machine architecture was driven by the design of algorithms whose requirements are reflected in the resulted instruction set(s). A few of these algorithms are described.

  10. Plant electrical memory.

    PubMed

    Volkov, Alexander G; Carrell, Holly; Adesina, Tejumade; Markin, Vladislav S; Jovanov, Emil

    2008-07-01

    Electrical signaling, short-term memory and rapid closure of the carnivorous plant Dionaea muscipula Ellis (Venus flytrap) have been attracting the attention of researchers since the XIX century. We found that the electrical stimulus between a midrib and a lobe closes the Venus flytrap upper leaf without mechanical stimulation of trigger hairs. The closing time of Venus flytrap by electrical stimulation is the same as mechanically induced closing. Transmission of a single electrical charge between a lobe and the midrib causes closure of the trap and induces an electrical signal propagating between both lobes and midrib. The Venus flytrap can accumulate small subthreshold charges, and when the threshold value is reached, the trap closes. Repeated application of smaller charges demonstrates the summation of stimuli. The cumulative character of electrical stimuli points to the existence of short-term electrical memory in the Venus flytrap.

  11. Memory for humorous cartoons.

    PubMed

    Schmidt, S R; Williams, A R

    2001-03-01

    Incidental memory for three types of cartoons was compared: original cartoons, literal translations of the originals, and weird cartoons created by inserting incongruous material into the literal translations. In Experiment 1, the three types of cartoons were mixed together in lists. In Experiment 2, each list contained only two cartoon types. In both experiments, original cartoons were remembered better than the literal and the weird cartoons, whereas the literal and the weird cartoons were equally well remembered. The detection of incongruities, or attempts to resolve those incongruities, cannot adequately explain the observed humor effects. The results were also inconsistent with both rehearsal and distinctiveness interpretations. Rather, humor per se appears to support good memory performance. Perhaps participants elaborated or gave sustained attention to humorous material at the expense of less humorous material.

  12. Place memory in crickets

    PubMed Central

    Wessnitzer, Jan; Mangan, Michael; Webb, Barbara

    2008-01-01

    Certain insect species are known to relocate nest or food sites using landmarks, but the generality of this capability among insects, and whether insect place memory can be used in novel task settings, is not known. We tested the ability of crickets to use surrounding visual cues to relocate an invisible target in an analogue of the Morris water maze, a standard paradigm for spatial memory tests on rodents. Adult female Gryllus bimaculatus were released into an arena with a floor heated to an aversive temperature, with one hidden cool spot. Over 10 trials, the time taken to find the cool spot decreased significantly. The best performance was obtained when a natural scene was provided on the arena walls. Animals can relocate the position from novel starting points. When the scene is rotated, they preferentially approach the fictive target position corresponding to the rotation. We note that this navigational capability does not necessarily imply the animal has an internal spatial representation. PMID:18230590

  13. Misaligned feeding impairs memories

    PubMed Central

    Loh, Dawn H; Jami, Shekib A; Flores, Richard E; Truong, Danny; Ghiani, Cristina A; O’Dell, Thomas J; Colwell, Christopher S

    2015-01-01

    Robust sleep/wake rhythms are important for health and cognitive function. Unfortunately, many people are living in an environment where their circadian system is challenged by inappropriate meal- or work-times. Here we scheduled food access to the sleep time and examined the impact on learning and memory in mice. Under these conditions, we demonstrate that the molecular clock in the master pacemaker, the suprachiasmatic nucleus (SCN), is unaltered while the molecular clock in the hippocampus is synchronized by the timing of food availability. This chronic circadian misalignment causes reduced hippocampal long term potentiation and total CREB expression. Importantly this mis-timed feeding resulted in dramatic deficits in hippocampal-dependent learning and memory. Our findings suggest that the timing of meals have far-reaching effects on hippocampal physiology and learned behaviour. DOI: http://dx.doi.org/10.7554/eLife.09460.001 PMID:26652002

  14. TED KYCIA MEMORIAL SYMPOSIUM.

    SciTech Connect

    LITTENBERG, L.; RUBINSTEIN, R.; SAMIOS, N.; LI, K.; GIACOMELLI, G.; MOCKETT, P.; CARROLL, A.; JOHNSON, R.; BRYMAN, D.; TIPPENS, B.

    2000-05-19

    On the afternoon of May 19 2000, a Memorial Seminar was held in the BNL physics Large Seminar Room to honor the memory of Ted Kyeia, a prominent particle physicist who had been a member of the BNL staff for 40 years. Although it was understandably a somewhat sad occasion because Ted was no longer with us, nevertheless there was much for his colleagues and friends to celebrate in recalling the outstanding contributions that he had made in those four decades. The Seminar speakers were all people who had worked with Ted during that period; each discussed one aspect of his career, but also included anecdotes and personal reminiscences. This booklet contains the Seminar program, listing the speakers, and also copies of transparencies of the talks (and one paper which was a later expansion of a talk); sadly, not all of the personal remarks appeared on the transparencies.

  15. Mechanisms of epigenetic memory

    PubMed Central

    D’Urso, Agustina; Brickner, Jason H.

    2014-01-01

    Although genetics play an essential role in defining an organism’s development, morphology and physiology, epigenetic mechanisms play an essential role in modulating these properties by regulating gene expression. During development, epigenetic mechanisms establish stable gene expression patterns to ensure proper differentiation. Epigenetic mechanisms also allow organisms to adapt to environmental changes and previous experiences can impact the future responsiveness of an organism to a stimulus over long time scales and even over generations. Here we discuss the concept of epigenetic memory, defined as the stable propagation of a change in gene expression or potentially induced by developmental or environmental stimuli. We highlight three distinct paradigms of epigenetic memory that operate on different time scales. PMID:24780085

  16. Optoelectronic associative memory

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin (Inventor)

    1993-01-01

    An associative optical memory including an input spatial light modulator (SLM) in the form of an edge enhanced liquid crystal light valve (LCLV) and a pair of memory SLM's in the form of liquid crystal televisions (LCTV's) forms a matrix array of an input image which is cross correlated with a matrix array of stored images. The correlation product is detected and nonlinearly amplified to illuminate a replica of the stored image array to select the stored image correlating with the input image. The LCLV is edge enhanced by reducing the bias frequency and voltage and rotating its orientation. The edge enhancement and nonlinearity of the photodetection improves the orthogonality of the stored image. The illumination of the replicate stored image provides a clean stored image, uncontaminated by the image comparison process.

  17. Learning, memory, and synesthesia.

    PubMed

    Witthoft, Nathan; Winawer, Jonathan

    2013-03-01

    People with color-grapheme synesthesia experience color when viewing written letters or numerals, usually with a particular color evoked by each grapheme. Here, we report on data from 11 color-grapheme synesthetes who had startlingly similar color-grapheme pairings traceable to childhood toys containing colored letters. These are the first and only data to show learned synesthesia of this kind in more than a single individual. Whereas some researchers have focused on genetic and perceptual aspects of synesthesia, our results indicate that a complete explanation of synesthesia must also incorporate a central role for learning and memory. We argue that these two positions can be reconciled by thinking of synesthesia as the automatic retrieval of highly specific mnemonic associations, in which perceptual contents are brought to mind in a manner akin to mental imagery or the perceptual-reinstatement effects found in memory studies.

  18. Sparse distributed memory

    NASA Technical Reports Server (NTRS)

    Denning, Peter J.

    1989-01-01

    Sparse distributed memory was proposed be Pentti Kanerva as a realizable architecture that could store large patterns and retrieve them based on partial matches with patterns representing current sensory inputs. This memory exhibits behaviors, both in theory and in experiment, that resemble those previously unapproached by machines - e.g., rapid recognition of faces or odors, discovery of new connections between seemingly unrelated ideas, continuation of a sequence of events when given a cue from the middle, knowing that one doesn't know, or getting stuck with an answer on the tip of one's tongue. These behaviors are now within reach of machines that can be incorporated into the computing systems of robots capable of seeing, talking, and manipulating. Kanerva's theory is a break with the Western rationalistic tradition, allowing a new interpretation of learning and cognition that respects biology and the mysteries of individual human beings.

  19. Short-term inhibition of 11β-hydroxysteroid dehydrogenase type 1 reversibly improves spatial memory but persistently impairs contextual fear memory in aged mice

    PubMed Central

    Wheelan, Nicola; Webster, Scott P.; Kenyon, Christopher J.; Caughey, Sarah; Walker, Brian R.; Holmes, Megan C.; Seckl, Jonathan R.; Yau, Joyce L.W.

    2015-01-01

    High glucocorticoid levels induced by stress enhance the memory of fearful events and may contribute to the development of anxiety and posttraumatic stress disorder. In contrast, elevated glucocorticoids associated with ageing impair spatial memory. We have previously shown that pharmacological inhibition of the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) improves spatial memory in aged mice. However, it is not known whether inhibition of 11β-HSD1 will have any beneficial effects on contextual fear memories in aged mice. Here, we examined the effects of UE2316, a selective 11β-HSD1 inhibitor which accesses the brain, on both spatial and contextual fear memories in aged mice using a vehicle-controlled crossover study design. Short-term UE2316 treatment improved spatial memory in aged mice, an effect which was reversed when UE2316 was substituted with vehicle. In contrast, contextual fear memory induced by foot-shock conditioning was significantly reduced by UE2316 in a non-reversible manner. When the order of treatment was reversed following extinction of the original fear memory, and a second foot-shock conditioning was given in a novel context, UE2316 treated aged mice (previously on vehicle) now showed increased fear memory compared to vehicle-treated aged mice (previously on UE2316). Renewal of the original extinguished fear memory triggered by exposure to a new environmental context may explain these effects. Thus 11β-HSD1 inhibition reverses spatial memory impairments with ageing while reducing the strength and persistence of new contextual fear memories. Potentially this could help prevent anxiety-related disorders in vulnerable elderly individuals. PMID:25497454

  20. Short-term inhibition of 11β-hydroxysteroid dehydrogenase type 1 reversibly improves spatial memory but persistently impairs contextual fear memory in aged mice.

    PubMed

    Wheelan, Nicola; Webster, Scott P; Kenyon, Christopher J; Caughey, Sarah; Walker, Brian R; Holmes, Megan C; Seckl, Jonathan R; Yau, Joyce L W

    2015-04-01

    High glucocorticoid levels induced by stress enhance the memory of fearful events and may contribute to the development of anxiety and posttraumatic stress disorder. In contrast, elevated glucocorticoids associated with ageing impair spatial memory. We have previously shown that pharmacological inhibition of the intracellular glucocorticoid-amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) improves spatial memory in aged mice. However, it is not known whether inhibition of 11β-HSD1 will have any beneficial effects on contextual fear memories in aged mice. Here, we examined the effects of UE2316, a selective 11β-HSD1 inhibitor which accesses the brain, on both spatial and contextual fear memories in aged mice using a vehicle-controlled crossover study design. Short-term UE2316 treatment improved spatial memory in aged mice, an effect which was reversed when UE2316 was substituted with vehicle. In contrast, contextual fear memory induced by foot-shock conditioning was significantly reduced by UE2316 in a non-reversible manner. When the order of treatment was reversed following extinction of the original fear memory, and a second foot-shock conditioning was given in a novel context, UE2316 treated aged mice (previously on vehicle) now showed increased fear memory compared to vehicle-treated aged mice (previously on UE2316). Renewal of the original extinguished fear memory triggered by exposure to a new environmental context may explain these effects. Thus 11β-HSD1 inhibition reverses spatial memory impairments with ageing while reducing the strength and persistence of new contextual fear memories. Potentially this could help prevent anxiety-related disorders in vulnerable elderly individuals.

  1. Procognitive effect of AC-3933 in aged mice, and synergistic effect of combination with donepezil in scopolamine-treated mice.

    PubMed

    Hashimoto, Takashi; Hatayama, Yuki; Nakamichi, Keiko; Yoshida, Naoyuki

    2014-12-15

    We have previously reported that AC-3933, a newly developed benzodiazepine receptor partial inverse agonist, facilitates acetylcholine release in the hippocampus and ameliorates scopolamine-induced memory deficits in rats. To further confirm the procognitive effect of AC-3933, we assessed in this study the beneficial effects of this compound in aged mice using the Y-maze and object recognition tests. In addition, we investigated the synergistic effect of AC-3933 and donepezil, a cholinesterase inhibitor, on scopolamine-induced memory impairment in mice. In aged mice, oral administration of AC-3933 at doses of 0.05-0.1 mg/kg and 0.05 mg/kg significantly improved spatial working memory and episodic memory, respectively. In scopolamine-treated mice, both AC-3933 and donepezil significantly ameliorated memory deficits in the Y-maze test at doses of 0.3-3 mg/kg and 10-15 mg/kg, respectively. The beneficial effect of AC-3933, but not that of donepezil, on scopolamine-induced memory impairment was antagonized by flumazenil, a benzodiazepine receptor antagonist, indicating that the procognitive action of AC-3933 arises via a mechanism different from that of donepezil. Co-administration of donepezil at the suboptimal dose of 3 mg/kg with AC-3933 at doses of 0.1-1 mg/kg significantly ameliorated scopolamine-induced memory impairment, suggesting that AC-3933 potentiates the effect of donepezil on memory impairment induced by cholinergic hypofunction. These findings indicate that AC-3933 not only has good potential as a cognitive enhancer by itself, but also is useful as a concomitant drug for the treatment of Alzheimer׳s disease.

  2. Fuzzy associative memories

    NASA Technical Reports Server (NTRS)

    Kosko, Bart

    1991-01-01

    Mappings between fuzzy cubes are discussed. This level of abstraction provides a surprising and fruitful alternative to the propositional and predicate-calculas reasoning techniques used in expert systems. It allows one to reason with sets instead of propositions. Discussed here are fuzzy and neural function estimators, neural vs. fuzzy representation of structured knowledge, fuzzy vector-matrix multiplication, and fuzzy associative memory (FAM) system architecture.

  3. Shape memory alloy actuator

    DOEpatents

    Varma, Venugopal K.

    2001-01-01

    An actuator for cycling between first and second positions includes a first shaped memory alloy (SMA) leg, a second SMA leg. At least one heating/cooling device is thermally connected to at least one of the legs, each heating/cooling device capable of simultaneously heating one leg while cooling the other leg. The heating/cooling devices can include thermoelectric and/or thermoionic elements.

  4. Epigenetic memory in plants

    PubMed Central

    Iwasaki, Mayumi; Paszkowski, Jerzy

    2014-01-01

    Epigenetics refers to heritable changes in patterns of gene expression that occur without alterations in DNA sequence. The epigenetic mechanisms involve covalent modifications of DNA and histones, which affect transcriptional activity of chromatin. Since chromatin states can be propagated through mitotic and meiotic divisions, epigenetic mechanisms are thought to provide heritable ‘cellular memory’. Here, we review selected examples of epigenetic memory in plants and briefly discuss underlying mechanisms. PMID:25104823

  5. Shape Memory Actuator System

    DTIC Science & Technology

    1998-07-31

    The advantage in utilizing 15 shape-memory cables made of Nitinol for size reduction of the remote control actuator system is 1 Fi well suited for...a submarine environment because of its non-magnetic and corrosion resistance 17 properties. Use of thermoelastic Nitinol introduces other...problems because of the cooling and 18 resetting properties of Nitinol cables. It is therefore an important object of the present invention 19 on to

  6. Memory metal actuator

    NASA Technical Reports Server (NTRS)

    Ruoff, C. F. (Inventor)

    1985-01-01

    A mechanical actuator can be constructed by employing a plurality of memory metal actuator elements in parallel to control the amount of actuating force. In order to facilitate direct control by digital control signals provided by a computer or the like, the actuating elements may vary in stiffness according to a binary relationship. The cooling or reset time of the actuator elements can be reduced by employing Peltier junction cooling assemblies in the actuator.

  7. Representation in Memory.

    DTIC Science & Technology

    1983-06-07

    notion of the schema finds its way into modern cognitive psychology from the writings of Bartlett (1932) and from Piaget (1952). Throughout most of its...Anderson. Cognitive algebra: Information integration applied to social attribution. December, 1972. 32. Jean H. Handler and Nancy L. Stein. Recall...knowledge in memory. January, 1976. 56. David E. Rumelhart. Toward an interactive model of reading. March, 1976. 57. Jean M. Handler, Nancy S

  8. [From memories about war].

    PubMed

    Spivak, B A

    2010-04-01

    The article presents publication of memories of a military physician Spivak B.A., finished the First Kiev medical institute in 1941. The author held rank: from August 1941--chief of sanitary service of a separated battalion, April 1942-June 1945--chief of operation-bandaging unit of 246 SMSB SD. After war served in military treatment institutes on ranks of surgical profile, finished the military service in the rank of chief of surgical unit of Kovel garrison hospital in 1964.

  9. Long-lasting memory from evanescent networks

    PubMed Central

    Routtenberg, Aryeh

    2010-01-01

    Current models of memory typically require a protein synthetic step leading to a more or less permanent structural change in synapses of the network that represent the stored information. This instructive role of protein synthesis has recently been called into question [Routtenberg, A., Rekart, J.L. 2005. Post-translational modification of synaptic proteins as the substrate for long-lasting memory. Trends Neurosci. 28, 12–19]. In its place a new theory is proposed in which post-translational modifications (PTMs) of proteins already synthesized and present within the synapse calibrate synaptic strength. PTM is thus the only mechanism required to sustain long-lasting memories. Activity-induced, PTM-dependent structural modifications within brain synapses then define network formation which is thus a product of the concatenation of cascaded PTMs. This leads to a formulation different from current protein synthesis models in which neural networks initially formed from these individual synaptic PTM-dependent changes is maintained by regulated positive feedback maintains. One such positive feedback mechanism is ‘cryptic rehearsal’ typically referred to as ‘noise’ or ‘spontaneous’ activity. This activity is in fact not random or spontaneous but determined in a stochastic sense by the past history of activation of the nerve cell. To prevent promiscuous network formation, the regulated positive feedback maintains the altered state given specific decay kinetics for the PTM. The up or down state of individual synapses actually exists in an infinite number of intermediate states, never fully ‘up’, nor fully ‘down.’ The networks formed from these uncertain synapses are therefore metastable. A particular memory is also multiply represented by a ‘degenerate code’ so that should loss of a subset of representations occur, erasure can be protected against. This mechanism also solves the flexibility–stability problem by positing that the brain eschews

  10. Sleep Loss Produces False Memories

    PubMed Central

    Diekelmann, Susanne; Landolt, Hans-Peter; Lahl, Olaf; Born, Jan; Wagner, Ullrich

    2008-01-01

    People sometimes claim with high confidence to remember events that in fact never happened, typically due to strong semantic associations with actually encoded events. Sleep is known to provide optimal neurobiological conditions for consolidation of memories for long-term storage, whereas sleep deprivation acutely impairs retrieval of stored memories. Here, focusing on the role of sleep-related memory processes, we tested whether false memories can be created (a) as enduring memory representations due to a consolidation-associated reorganization of new memory representations during post-learning sleep and/or (b) as an acute retrieval-related phenomenon induced by sleep deprivation at memory testing. According to the Deese, Roediger, McDermott (DRM) false memory paradigm, subjects learned lists of semantically associated words (e.g., “night”, “dark”, “coal”,…), lacking the strongest common associate or theme word (here: “black”). Subjects either slept or stayed awake immediately after learning, and they were either sleep deprived or not at recognition testing 9, 33, or 44 hours after learning. Sleep deprivation at retrieval, but not sleep following learning, critically enhanced false memories of theme words. This effect was abolished by caffeine administration prior to retrieval, indicating that adenosinergic mechanisms can contribute to the generation of false memories associated with sleep loss. PMID:18946511

  11. Unifying Memory and Database Transactions

    NASA Astrophysics Data System (ADS)

    Dias, Ricardo J.; Lourenço, João M.

    Software Transactional Memory is a concurrency control technique gaining increasing popularity, as it provides high-level concurrency control constructs and eases the development of highly multi-threaded applications. But this easiness comes at the expense of restricting the operations that can be executed within a memory transaction, and operations such as terminal and file I/O are either not allowed or incur in serious performance penalties. Database I/O is another example of operations that usually are not allowed within a memory transaction. This paper proposes to combine memory and database transactions in a single unified model, benefiting from the ACID properties of the database transactions and from the speed of main memory data processing. The new unified model covers, without differentiating, both memory and database operations. Thus, the users are allowed to freely intertwine memory and database accesses within the same transaction, knowing that the memory and database contents will always remain consistent and that the transaction will atomically abort or commit the operations in both memory and database. This approach allows to increase the granularity of the in-memory atomic actions and hence, simplifies the reasoning about them.

  12. Sleep loss produces false memories.

    PubMed

    Diekelmann, Susanne; Landolt, Hans-Peter; Lahl, Olaf; Born, Jan; Wagner, Ullrich

    2008-01-01

    People sometimes claim with high confidence to remember events that in fact never happened, typically due to strong semantic associations with actually encoded events. Sleep is known to provide optimal neurobiological conditions for consolidation of memories for long-term storage, whereas sleep deprivation acutely impairs retrieval of stored memories. Here, focusing on the role of sleep-related memory processes, we tested whether false memories can be created (a) as enduring memory representations due to a consolidation-associated reorganization of new memory representations during post-learning sleep and/or (b) as an acute retrieval-related phenomenon induced by sleep deprivation at memory testing. According to the Deese, Roediger, McDermott (DRM) false memory paradigm, subjects learned lists of semantically associated words (e.g., "night", "dark", "coal",...), lacking the strongest common associate or theme word (here: "black"). Subjects either slept or stayed awake immediately after learning, and they were either sleep deprived or not at recognition testing 9, 33, or 44 hours after learning. Sleep deprivation at retrieval, but not sleep following learning, critically enhanced false memories of theme words. This effect was abolished by caffeine administration prior to retrieval, indicating that adenosinergic mechanisms can contribute to the generation of false memories associated with sleep loss.

  13. Predicting confidence in flashbulb memories.

    PubMed

    Day, Martin V; Ross, Michael

    2014-01-01

    Years after a shocking news event many people confidently report details of their flashbulb memories (e.g., what they were doing). People's confidence is a defining feature of their flashbulb memories, but it is not well understood. We tested a model that predicted confidence in flashbulb memories. In particular we examined whether people's social bond with the target of a news event predicts confidence. At a first session shortly after the death of Michael Jackson participants reported their sense of attachment to Michael Jackson, as well as their flashbulb memories and emotional and other reactions to Jackson's death. At a second session approximately 18 months later they reported their flashbulb memories and confidence in those memories. Results supported our proposed model. A stronger sense of attachment to Jackson was related to reports of more initial surprise, emotion, and rehearsal during the first session. Participants' bond with Michael Jackson predicted their confidence but not the consistency of their flashbulb memories 18 months later. We also examined whether participants' initial forecasts regarding the persistence of their flashbulb memories predicted the durability of their memories. Participants' initial forecasts were more strongly related to participants' subsequent confidence than to the actual consistency of their memories.

  14. Amodal completion in visual working memory.

    PubMed

    Chen, Siyi; Müller, Hermann J; Conci, Markus

    2016-09-01

    Amodal completion refers to the perceptual "filling-in" of partly occluded object fragments. Previous work has shown that object completion occurs efficiently, at early perceptual stages of processing. However, despite efficient early completion, at a later stage, the maintenance of complete-object representations in visual working memory (VWM) may be severely restricted due to limited mnemonic resources being available. To examine for such a limitation, we investigated whether the structure of to-be-remembered objects influences what is encoded and maintained in VWM using a change detection paradigm. Participants were presented with a memory display that contained either "composite" objects, that is, notched shapes abutting an occluding square, or equivalent unoccluded, "simple" objects. The results showed overall increased memory performance for simple relative to composite objects. Moreover, evidence for completion in VWM was found for composite objects that were interpreted as globally completed wholes, relative to local completions or an uncompleted mosaic (baseline) condition. This global completion advantage was obtained only when the "context" of simple objects also supported a global object interpretation. Finally, with an increase in memory set size, the global object advantage decreased substantially. These findings indicate that processes of amodal completion influence VWM performance until some overall-capacity limitation prevents completion. VWM completion processes do not operate automatically; rather, the representation format is determined top-down based on the simple object context provided. Overall, these findings support the notion of VWM as a capacity-limited resource, with storage capacity depending on the structured representation of to-be-remembered objects. (PsycINFO Database Record

  15. Memory suppression trades prolonged fear and sleep-dependent fear plasticity for the avoidance of current fear

    NASA Astrophysics Data System (ADS)

    Kuriyama, Kenichi; Honma, Motoyasu; Yoshiike, Takuya; Kim, Yoshiharu

    2013-07-01

    Sleep deprivation immediately following an aversive event reduces fear by preventing memory consolidation during homeostatic sleep. This suggests that acute insomnia might act prophylactically against the development of posttraumatic stress disorder (PTSD) even though it is also a possible risk factor for PTSD. We examined total sleep deprivation and memory suppression to evaluate the effects of these interventions on subsequent aversive memory formation and fear conditioning. Active suppression of aversive memory impaired retention of event memory. However, although the remembered fear was more reduced in sleep-deprived than sleep-control subjects, suppressed fear increased, and seemed to abandon the sleep-dependent plasticity of fear. Active memory suppression, which provides a psychological model for Freud's ego defense mechanism, enhances fear and casts doubt on the potential of acute insomnia as a prophylactic measure against PTSD. Our findings bring into question the role of sleep in aversive-memory consolidation in clinical PTSD pathophysiology.

  16. Memory suppression trades prolonged fear and sleep-dependent fear plasticity for the avoidance of current fear

    PubMed Central

    Kuriyama, Kenichi; Honma, Motoyasu; Yoshiike, Takuya; Kim, Yoshiharu

    2013-01-01

    Sleep deprivation immediately following an aversive event reduces fear by preventing memory consolidation during homeostatic sleep. This suggests that acute insomnia might act prophylactically against the development of posttraumatic stress disorder (PTSD) even though it is also a possible risk factor for PTSD. We examined total sleep deprivation and memory suppression to evaluate the effects of these interventions on subsequent aversive memory formation and fear conditioning. Active suppression of aversive memory impaired retention of event memory. However, although the remembered fear was more reduced in sleep-deprived than sleep-control subjects, suppressed fear increased, and seemed to abandon the sleep-dependent plasticity of fear. Active memory suppression, which provides a psychological model for Freud's ego defense mechanism, enhances fear and casts doubt on the potential of acute insomnia as a prophylactic measure against PTSD. Our findings bring into question the role of sleep in aversive-memory consolidation in clinical PTSD pathophysiology. PMID:23863955

  17. Dreams are made of memories, but maybe not for memory.

    PubMed

    Blagrove, Mark; Ruby, Perrine; Eichenlaub, Jean-Baptiste

    2013-12-01

    Llewellyn's claim that rapid eye movement (REM) dream imagery may be related to the processes involved in memory consolidation during sleep is plausible. However, whereas there is voluntary and deliberate intention behind the construction of images in the ancient art of memory (AAOM) method, there is a lack of intentionality in producing dream images. The memory for dreams is also fragile, and dependent on encoding once awake.

  18. Investigating Memory Development in Children and Infantile Amnesia in Adults

    ERIC Educational Resources Information Center

    Kazemi Tari, Somayeh

    2008-01-01

    Although many researchers have worked on memory development, still little is known about what develops in memory development. When one reviews the literature about memory, she encounters many types of memories such as short term vs. long term memory, working memory, explicit vs. implicit memory, trans-saccadic memory, autobiographical memory,…

  19. The Nature of Individual Differences in Working Memory Capacity: Active Maintenance in Primary Memory and Controlled Search from Secondary Memory

    ERIC Educational Resources Information Center

    Unsworth, Nash; Engle, Randall W.

    2007-01-01

    Studies examining individual differences in working memory capacity have suggested that individuals with low working memory capacities demonstrate impaired performance on a variety of attention and memory tasks compared with individuals with high working memory capacities. This working memory limitation can be conceived of as arising from 2…

  20. An investigation of errorless learning in memory-impaired patients: improving the technique and clarifying theory.

    PubMed

    Tailby, Rebecca; Haslam, Catherine

    2003-01-01

    In rehabilitating individuals who demonstrate severe memory impairment, errorless learning techniques have proven particularly effective. Prevention of errors during acquisition of information leads to better memory than does learning under errorful conditions. This paper presents results of a study investigating errorless learning in three patient groups: those demonstrating mild, moderate, and severe memory impairments. The first goal of the study was to trial a new version of errorless learning, one encouraging more active participation in learning by patients via the use of elaboration and self-generation. This technique led to significantly better memory performance than seen under standard errorless conditions. This finding highlights the value of encouraging active and meaningful involvement by patients in errorless learning, to build upon the benefits flowing from error prevention. A second goal of the study was to clarify the mechanisms underlying errorless learning. Memory performance under errorless and errorful conditions was compared within and across each group of patients, to facilitate theoretical insight into the memory processes underlying performance. The pattern of results observed was equivocal. The data most strongly supported the hypothesis that the benefits seen under errorless learning reflect the operation of residual explicit memory processes, however a concurrent role for implicit memory processes was not ruled out.