Outcomes are inconsistent in various dual tasks used for measuring divided attention. Sleep deprivation of 24 h impaired performance in one study Wright and Badiawhereas in two others, performance was maintained after 25—35 h of SD Drummond et al ; Alhola et al The divergent findings in these studies may be explained by the uneven loads between different subtests as well as by uncontrolled practice effect. Although dividing attention between different tasks puts high demands on cognitive capacity, subjects often attempt to reduce the load by automating some easier procedures of a dual or multitask.
The extremely depressed person feels much better if he goes without REM sleep for a night or two. The suicidally depressed patient may forget the idea of suicide for a few hours or days if he is deprived of REM for a night or two. These basic observations have been confirmed many times since the s see the reading list below but the question as to how REM deprivation helps depression has been left unanswered.
Despite the dramatic beneficial effects on serious depression we still have no idea as to why REM deprivation alleviates, at least temporarily, major depression. This is a very surprising fact. You would think that any clue or lead on what kinds of treatment work for major depression would be followed up on with major pushes in the research arena backed up by major funding streams from the National Institutes of Health.
But the voices of depressed people, apparently, are not as loud as the voices of other health-related interest groups so funding for depression studies has never been adequate to the scale fo the problem. A recent study, however, has managed to throw some fascinating light on the relations between acute sleep deprivation and alleviation of depression.
In addition, this amplified reactivity was associated with a biased increase in the number of emotional stimuli judged as pleasant in the sleep-deprived group. In short, it appears that acute sleep deprivation increases reactivity in reward networks of the brain.
The older neurobiological literature on REM deprivation in animals suggested that motivational and drive related states were heightened during after REM deprivation as animals seemed much more attuned to reinforcing and pleasureable stimuli.
These facts led the older researchers to suggest that the normal function of REM was to dampen down pleasureable or motivational states or that REM functioned to re-tune catecholaminergic synapses throughout the brain.
In any case both the older literature and the newer data suggest that REM specializes in handling negative motivational and appetitive states and thus it should not be surprising that REM deprivation has a potent if temporary anti-depressant effect.
Nor should it be surprizing that REM indices are virtually always elevated in major depression. It seems that major depression is fueled at least in part by a kind of dis-inhibition of REM physiology. Relevant articles Agargun, M. REM sleep, dream variables and suicidality in depressed patients.
Psychiatry Research, Repetitive frightening dreams and suicidal behavior in patients with major depression. Comprehensive Psychiatry, 39, Nightmaressuicide attempts, and melancholic features in patients with unipolar major depression.
Journal of Affective Disorders, 98, Diagnostic and statistical manual of mental disorders 4th ed. American Psychiatric Association Press. Comparison of word frequencies by cognitive classes. Sleep and circadian rhythms in mood disorders. Acta Psychiatrica Scandinavica, s Bi-directional changes in regional cerebral blood flow across the first 20 min of wakefulness.
Sleep Research Online, 2 Suppl. Reduction of prefrontal cortex glucose metabolism common to three types of depression. Archives of General Psychiatry, 46, Journal of Experimental Psychology: Learning, Memory, and Cognition Dissociable Effects of Surprising Rewards on Learning and Memory Nina Rouhani, Kenneth A.
Norman, and Yael Niv. Effect of Sleep on Memory This article is from The Journal of Experimental Psychology, and was written on an experiment performed by psychologist Bruce R.
Ekstrand, from the University of Colorado.
The levels-of-processing effect, identified by Fergus I. M. Craik and Robert S. Lockhart in , describes memory recall of stimuli as a function of the depth of mental processing.
Deeper levels of analysis produce more elaborate, longer-lasting, and stronger memory traces than shallow levels of analysis. Depth of processing falls on a shallow to deep continuum. The Journal of Experimental Psychology: General ® publishes articles describing empirical work that is of broad interest or bridges the traditional interests of two or more communities of psychology.
However, researchers believe sleep is required for consolidation of a memory, no matter the memory type. Without adequate sleep, your brain has a harder time absorbing and recalling new information.
Sleep does more than help sharpen the mind. Studies show that sleep affects physical reflexes, fine motor skills, and judgment, too. The Effects of Sleep Deprivation on Memory, Problem Solving, and Critical Thinking 9 As studies have been conducted, the majority have seemed to come to similar conclusions: a lack of sleep can have detrimental side effects on the human mind and body, and by regularly obtaining.