Although insomnia is common and disabling, its neural correlates remain enigmatic. Stoffers et al. use structural and functional MRI to demonstrate that hyperarousal, its clearest characteristic, involves reduced recruitment and connectivity of the left caudate that may predispose to insomnia and perpetuate it.

This study investigated the influence of aging on memory for home drams and the extent to which cognitive variables such as visual memory, visuospatial IQ, and verbal IQ could account for possible differences herein. Subjects were 80 men and women of ages 45 to 75 years. Memory for dreams was measured by narrative length and frequency of recall. With respect to both measures no significant age differences were noted. Over-all differences in dream recall seemed best explained by visual memory scores. Partial correlational analyses, however, indicated that the small age differences memory or on any of the other cognitive variables. Dream contents were scored for aggression, friendliness, emotion, activities, and the number of characters and objects. The incidence of emotions among women appeared to be lower beyond the age of 60. Comparisons with previous data for young adults indicated that large reductions in aggression, friendliness, and emotion occur before the age of 45.

This article focuses attention on the perennial issue of home versus laboratory recording situations for the garnering of dream reports. Studies into the experimental control over procedures for both waking and interviewing are reviewed. Against this background, an experiment into the relationship between REM/NREM sleep and visual imagery is reported. We found that, having corrected for total word count, visual imagery still made an independent contribution to REM reports. This finding is evaluated in the light of differential cognitive mechanisms underlying dream formation during sleep.

SUMMARY  EEG spectral power was studied during periods of rapid eye movements (REMs) and tonic intervals in REM sleep of 7 young and 7 older male subjects. Significant symmetrical decreases in alpha and betal power at central and occipital sites, concurrent with an increase in frontal theta power, were observed during the production of REMs. The former findings are discussed as sleep analogues to changes in alpha and betal during waking, showing increased information processing and behavioural activation, and that of theta is tentatively presented as reflecting an increase in afferent thresholds. Independent of the phasic‐tonic REM distinction, total EEG power markedly decreased as a function of time of night and did not interact with age. Significant age differences in the overall spectral composition of the EEG were obtained, namely, a lower level of delta power and a relative shift towards more power in frequencies above 12 Hz for the older group. Further, older subjects also demonstrated a more uniform topographical distribution of alpha and sigma power.

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