In the visual domain, involuntary allocation of attentional resources can be induced by using peripheral cues. An enlargement of the P1 ERP-component has been reported in connection with voluntary allocation of resources induced by symbolic cues, but until recently, it has not been reported in connection with involuntary allocation of resources. However, involuntary allocation of resources was only investigated with long cue-target intervals (SOAs) of about 600 ms. Therefore, an experiment was conducted with SOAs between 100 and 300 ms. After a 100% valid peripheral cue a bilateral multi-item array was presented. Trend analyses, which were employed to estimate the ERP elicited by the array corrected for linear and nonlinear contribution of the cue, showed a contralateral enhancement for the posterior P150 and the N230 component. Hence, involuntary allocation of resources with short SOAs might invoke the same level as voluntary allocation of resources. The P150 enhancement may be interpreted as a reflection of allocated resources at a specific location, whereas the N230 enhancement might reflect elaborated processing at the contralateral hemisphere.

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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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