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Biomedical subjects

W B Webb

Publications and source records attributed to W B Webb.

At least 55 records · Page 3Linked to original sources
PubMed1981

The perception of wakefulness within sleep.

We studied the relationship between electroencephalographic (EEG)-defined awakenings and subjects' awareness of them at the time of their occurrence in 40 men (mean age, 55.3 years). The subjects used a push-button device to signal wakefulness during an evening's sleep in the laboratory; continuous EEG and electro-oculograms were also made. Results were as follows (after eliminating data for 12 nonresponders): 52% of the responses occurred during EEG-defined wakefulness (stage 0), 12% in a sleep stage that was followed immediately by stage 0, and 36% in a sleep stage not followed by stage 0. However, analysis of the last finding indicated that 73% of these responses were associated with at least 4-6 sec of preceding alpha activity. Thus, signals in the absence of EEG criteria were actually less than 10% of the total recorded. Signals of wakefulness were closely associated with the onset of EEG-defined wakefulness (and 84% of the signals occurred within 4 sec to 1 min of the EEG period). We conclude that self-signaled arousals deserve consideration in clinical analyses in which reports of arousals are a part of the reported sleep disturbance.

Arousal↗
PubMed1980

Awakenings and the return to sleep in an older population.

The return-to-sleep latencies of 36 older females were examined and compared to latencies of a younger population in an effort to further understand the awakenings within sleep associated with aging. Results indicate that in addition to an increase in spontaneous arousals, the time necessary for the return to sleep is also extended as a function of aging. It is suggested that two semi-independent patterns may be found in arousals: frequent, short arousal and infrequent awakenings of longer duration.

Aging↗
PubMed1979

The return to sleep.

Six young adult subjects were awakened five to eight times per night from stage 2 sleep in a standardized manner for a series of at least 11 non-consecutive nights. After adaptation to the procedure, subjects received placebo, pentobarbital, or flurazepam on two random nights and caffeine on one night. The latency of the return to sleep after each awakening was measured. On placebo nights a characteristic U-shaped curve of latency as a function of time of night was found. Latencies were long shortly after sleep onset but decreased rapidly to about 50 sec before beginning an approximately linear logarithmic increase throughout the rest of the night. The drugs characteristically altered this time course. Pentobarbital decreased latencies in the first half of the night. Flurazepam decreased latencies throughout the night. Caffeine increased latencies during the first half of the night.

Adult↗
PubMed1979

Effect of flurazepam, pentobarbital, and caffeine on arousal threshold.

After laboratory and procedure adaptation, 6 normal subjects were randomly administered 30 mg flurazepam (twice), 100 mg pentobarbital (twice), 400 mg caffeine (once), and placebo (twice) on nonconsecutive nights. On each night subjects were aroused from standard segments of stage 2 sleep five to eight times with an ascending series of 1,000 Hz tones produced by an audiometer. Arousal threshold and awake threshold after each arousal were measured. Both thresholds were increased by flurazepam and pentobarbital and decreased by caffeine. All of the drugs appeared to modify arousal threshold in a time course fashion such that extreme effects were found during the first half of the night. However, the modifications of waking threshold by caffeine and flurazepam continued throughout the sleep period. The method may be a means of measuring the behavioral time course of drug activity during the sleep period.

Adult↗
PubMed1979

Sleep onset facilitation by tones.

In five successive sessions the effect on sleep latencies of three sound stimuli (silence, continuous sound, and an intermittent tone), as well as the combination of a tone plus counting or eye closing, were compared. Tests were conducted under a condition of "artificial insomnia": the subjects attempted sleep in the morning after a full night's sleep. No condition approached the latencies after a night of sleep deprivation. The intermittent tone and the tone plus counting were most effective and showed a differential sessions effect. The tone plus eye opening and closing was counterproductive.

Acoustic Stimulation↗
PubMed1978

The sleep of 'morning' and 'evening' types.

A questionnaire developed by Ostberg to differentiate 'morning' types from 'evening' types was administered to 100 college students. The actual sleep behavior of the 11 extreme 'morning' types (larks) and the 10 extreme 'evening' types (owls) was monitored for two weeks with a sleep log and the Post-sleep Inventory. Data was collected from the owls for a further two-week period in which the owls had been instructed to attempt to arise at the lark arousal time. In addition to going to bed earlier and getting up earlier than the owls, the larks had a less variable sleep length and awakening time and took shorter naps than the owls. Larks further reported fewer physical problems and less mental activity across the night as well as more adequate sleep than owls, who differed little from the normal college population even after having their awakening time shifted.

Activity Cycles↗
PubMed1978

The forty-eight hour day.

Four normal young adult male subjects were evaluated in a systematically imposed regime of 32 hr of wakefulness and 16 hr of sleep time in an environment free from time cues. Electroencephalographic and electrooculographic recordings were made continuously during the experiment, which lasted for 10 complete cycles. Sleep efficiency was assessed by determining the percentage of sleep time during the assigned sleep period. The average sleep efficiency for the experimental period was 77%. Results, in general, conformed to earlier findings of non-24 hr schedules of sleep and waking: the overall sleep system remains relatively stable across a variety of scheduled variations; however, utilization of the sleep period becomes less efficient as the schedule increasingly deviates from the normal approximately 16 hr wakefulness/8 hr sleep schedule.

Adolescent↗
PubMed1978

The spontaneous ending of sleep.

The last hour of spontaneous awakenings from uninterrupted sleep of 16 young adults was analyzed. In general, sleep was not fitful and broken but a continuation of the sleep process to the point of awakening. There were substantial individual differences in the time of awakening and the stage of sleep from which the sleeper emerged.

Adult↗
PubMed1978

Effects of rapidly rotating shifts on sleep patterns and sleep structure.

Six young adult males were assigned to a rapidly rotating shift work schedule (2 d 6 am-4 pm, 2 d 4 pm-10 pm, and 2 d 10 pm-6 am). They lived in the laboratory and completed two rotations. Their nonshift activities were ad libitum including sleep times. The patterns and structure of sleep were analyzed. Shift times systematically affected sleep patterns. Within shifts, Ss slept as late as possible prior to the morning shift, went to bed shortly after the night shift, and slept approximately midway between shifts on the afternoon shift. In transitioning to a new shift, the new shift time tended to determine sleep time. Sleep was significantly longer in transitions between shifts. Sleep structure was not markedly changed.

Adolescent↗
PubMed1978

The sleep of conjoined twins.

Conjoined twins with a common heart system and circulatory system were observed during the 14th and 15th days for 11 hr. Sleep, Waking, and Quiet and Active Sleep were recorded in minute intervals. Clear independence of sleep and waking was manifest, and total independence of Quiet and Active sleep was noted.

Humans↗