Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0751295 (memory loss)
 3,619 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report here the first sleep deprivation study done on a group of 5 healthy students (1 female, 4 males, 23-24 years of age) while playing a game (Triviant). In 2 persons an EEG was recorded for 6 consecutive 24 h periods with an ambulatory monitor from the baseline night until 72 h after deprivation. The baseline night showed normal hypnograms. The students were deprived of sleep for 65 h following the baseline night. Sleep deprivation was complete and resulted in bradyphrenia, loss of memory and contact with reality, ataxia, decrease in body temperature and loss of body weight. The main sign of recuperation was a strongly increased slow-wave sleep synchronization during the first recuperation period (day-time sleep) only. There were no signs of REM rebound.
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PMID:Long-term sleep deprivation as a game. The wear and tear of wakefulness. 132 May 35

This study evaluated the effects of flurazepam 30 mg, lorazepam 4 mg, triazolam 0.5 mg, and placebo upon sleep and memory in eleven normal male subjects continuously monitored for nighttime EEG, EOG, and EMG recording. Subjects received each drug or placebo for two consecutive nights per week for 4 weeks in a repeated measures, double-blind, Latin Square design. Three hours post-administration, subjects were awakened and presented with a series of tasks. Recall was assessed immediately following task presentation and after the final morning awakening. The results showed that every drug significantly decreased stage 1, increased stage 2, and produced no change in stage 3--4 sleep in comparison to placebo. Only lorazepam significantly decreased REM percent. Post-drug recall was significantly decreased in comparison to placebo at night and was further decreased in the morning. Morning recall was significantly poorer when the return to sleep was 2.5 min or less than when the return to sleep was greater than 5 min following the nighttime awakening in all drug conditions. These results indicate that 1. failure of memory consolidation rather than failure of retrieval is the most likely explanation for the morning memory loss and 2. hypnotic drug properties, measured by latency to fall back asleep, affect memory consolidation.
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PMID:The effects of flurazepam, lorazepam, and triazolam on sleep and memory. 610 88

Current theories of the cause of Alzheimer's disease (AD) do not address the question as to why AD patients initially and gradually lose their short-term memory, followed later by progressive and accelerated loss of other memory, language, motor skills, perception and very short-term memory. We propose that this pattern of memory loss may be a result of a REM sleep deficit or malfunction. This hypothesis is also supported by: 1) Results which show that AD patients have less REM sleep than controls. 2) There is an established close correspondence between learning/memory and REM sleep. REM sleep deprivation is known to result in impairment in learning recent information. 3) AD patients have a degenerated cholinergic system of the brain. The cholinergic system is known to activate/stimulate the REM sleep process. 4) The lesions in AD victims are primarily located in those regions of the brain that are considered to be active during REM sleep. 5) There is a natural mechanism by which the REM sleep in humans is reduced from 8 hours each day at birth to less than 1 hour each day in old age. An acceleration of this process can lead to possible REM deficit at old age. Furthermore, since old people have so little REM sleep they are more vulnerable to a REM sleep deficit. The REM sleep deficit mechanism may also work in conjunction with other theories of the etiology of AD, in which case, the REM sleep deficit may explain the progression and/or the acceleration of memory loss in AD.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Is Alzheimer's disease related to a deficit or malfunction of rapid eye movement (REM) sleep? 814 55

In case new diagnostic procedures for Alzheimer's dementia (AD) appear, Nuclear Medicine (NM) would like to be aware of them in order to evaluate its own contribution to diagnose AD by SPET and PET brain studies. Recently, sleep disturbances were studied in AD and tend to be diagnostic for early AD. In AD the actual time of night sleep was found to be 5.7 h, while awakeness time for the same night sleep increased to 2.7 h. Also in AD, the REM and the slow wave stage (SWS) during sleep are shorter and hypopnea and apnea phases are abundant. Internal body temperature during night sleep is only slightly increased in AD, while in temporofrontal dementia and in normal individuals this increase is significant. The circadian rhythm of melatonin is disturbed in AD. The normal duration of inspiration and expiration during daytime which is reversed during normal night sleep, has not been studied in patients with AD. However, this reverse condition favoring inspiration is expected to provide more oxygen to the brain. Chronic but not acute stress causes memory loss and is currently being studied by us as a possible causative factor for memory loss in AD. Tomographic SPET and PET brain studies can locate the site of brain damage in AD. This is important since memory has recently been classified into four categories, namely episodic, semantic, procedural and working memory. In early AD only procedural memory remains intact. This means that these patients may drive a car, do computer word processing and play some games at home or/and in the field. This memory is located in specific nuclei in the cerebellum and the occipital frontal area which do not relate to sites of other kinds of memory. This difference could be well identified by tomographic SPET or PET studies. Thus NM may also diagnose the early stage of AD. Another issue refers to the indications that the unified Medicare and Medicaid system in the USA has issued on September 15, 2004 for performing a PET (18)F-FDG study for AD. These indications are fully described in this editorial.
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PMID:[Alzheimer's dementia, sleep disorders and nuclear medicine]. 1588 44