A. Lubin

Bio: A. Lubin is an academic researcher from San Diego State University. The author has contributed to research in topics: Slow-wave sleep & Non-rapid eye movement sleep. The author has an hindex of 9, co-authored 12 publications receiving 523 citations.

Spontaneous electrodermal activity during waking and sleeping

Abstract: Spontaneous electrodermal activity (EDA) (galvanic skin response [GSR] and skin potential response [SPR]) was recorded during daytime sleep and nighttime sleep. During all sleep, spontaneous EDA occurred most frequently during stages 3 and 4 (slow wave sleep) and least frequently during stage 1 (rapid eye movement [REM] and non-REM). This pattern was consistent over 3 nights of sleep. There was no relation between waking and sleeping spontaneous EDA. The spontaneous EDA during slow wave sleep significantly exceeded that during waking. During sleep, spontaneous SPRs often occurred without spontaneous GSRs.

Autonomic correlates of eye movement bursts during stage rem sleep

Abstract: During stage REM sleep, eye movements were found to be distributed in discrete bursts of rapid eye movement (REM-bursts). REM-burst time averaged approximately 10 percent of stage REM sleep and the rate within a subject was consistent from epoch-to-epoch and night-to-night. Consistent subject biases in eye movement direction were also found. Within subject correlations were obtained between REM-burst time and autonomic activity. Significant positive correlations were found for respiration rate and number of finger pulse responses. There were positive but insignificant correlations with electrodermal activity, heart rate and decreases in respiration amplitude. Autonomic variability was not significantly associated with REM-burst time.

The evoked heart rate response during sleep

Abstract: Heart rate responses evoked by a 3-sec auditory stimulus were averaged within stages of sleep for five subjects. Although there were some individual differences, the evoked HR response is generally diphasic, with the peak of the acceleratory component occurring on the fourth post-stimulus beat and the trough of the deceleratory component occurring on the 10th post-stimulus beat. Unlike other variables, which are depressed during the rapid eye movement (REM) stage, the HR response tends to be larger during the REM stage than during other stages of sleep. The size of the response is not appreciably affected by time of night, since HR is non-habituating during sleep, but is affected by the respiratory cycle phase, being largest when the stimulus occurs during inspiration or the period immediately prior to inspiration, and smallest when the stimulus occurs during the expiratory phase.

Timing of human sleep: recovery process gated by a circadian pacemaker

Abstract: A model for the timing of human sleep is presented. It is based on a sleep-regulating variable (S)--possibly, but not necessarily, associated with a neurochemical substance--which increases during wakefulness and decreases during sleep. Sleep onset is triggered when S approaches an upper threshold (H); awakening occurs when S reaches a lower threshold (L). The thresholds show a circadian rhythm controlled by a single circadian pacemaker. Time constants of the S process were derived from rates of change of electroencephalographic (EEG) power density during regular sleep and during recovery from sleep deprivation. The waveform of the circadian threshold fluctuations was derived from spontaneous wake-up times after partial sleep deprivation. The model allows computer simulations of the main phenomena of human sleep timing, such as 1) internal desynchronization in the absence of time cues, 2) sleep fragmentation during continuous bed rest, and 3) circadian phase dependence of sleep duration during isolation from time cues, recovery from sleep deprivation, and shift work. The model shows that the experimental data are consistent with the concept of a single circadian pacemaker in humans. It has implications for the understanding of sleep as a restorative process and its timing with respect to day and night.

Dependence on REM sleep of overnight improvement of a perceptual skill

Abstract: Several paradigms of perceptual learning suggest that practice can trigger long-term, experience-dependent changes in the adult visual system of humans. As shown here, performance of a basic visual discrimination task improved after a normal night's sleep. Selective disruption of rapid eye movement (REM) sleep resulted in no performance gain during a comparable sleep interval, although non-REM slow-wave sleep disruption did not affect improvement. On the other hand, deprivation of REM sleep had no detrimental effects on the performance of a similar, but previously learned, task. These results indicate that a process of human memory consolidation, active during sleep, is strongly dependent on REM sleep.