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H M Ferres

Publications and source records attributed to H M Ferres.

6 recordsLinked to original sources
PubMed1978

Workload and fatigue--in-flight EEG changes.

Continuous recordings were made of the EEG and ECG of one pilot during a series of instrument flights in a feeder-type transport aircraft. The flights were arranged to contain epochs of distinctly differing levels of workload. In addition, some flights were made after a night of sleep deprivation and others were made as the second and third flights of the day. Subjectively, there appeared to be marked differences in performance between the two types of tired flight. The EEG analyses showed changes that correlated well with differences in workload. In the highest workload areas during fresh flights, EEG activity increased by approximately a factor of 4 over that of the preflight resting values. This large increase did not occur in the tired flights. Further experiments are planned using flights in aircraft and in simulators using several subjects.

Aerospace Medicine↗
PubMed1976

Effect of N-desmethyldiazepam (nordiazepam) and a precursor, potassium clorazepate, on sleep in man.

1 The effect of N-desmethyldiazepam (nordiazepam, 5 and 10 mg) and potassium clorazepate (15 mg, a precursor of nordiazepam) on sleep was studied in six healthy adult males. Electroencephalography (EEG) was used for sleep measures, and analogue scales were used for subjective assessments of well-being and sleep quality. 2 Effects on total sleep time were limited to the night of ingestion. There were increases with nordiazepam (5 and 10 mg) (P = 0.05) and 0.001 respectively), and with clorazepate (15 mg) (P = 0.01). Sleep onset latencies were shortened, particularly with nordiazepam, and awakening to stage 0 activity was reduced, by both drugs. The latency to stage 3 was reduced by nordiazepam (5 and 10 mg) (P = 0.05). 3 There were no effects of nordiazepam (5 mg) on the duration (min) of sleep stages. Nordiazepam (10 mg) and clorazepate (15 mg) reduced the duration of stage 0 and stage 1, and there were increases in stage 2. Reduced stage 1 and increased stage 2 sleep were observed during the recovery night. No effects were observed with stage 3, but there was evidence that stage 4 activity was depressed on the recovery night only. No effects were observed on REM sleep, except that the appearnace of the first REM period was delayed with clorazepate (15 mg) P = 0.01). The effect of nordiazepam (10 mg) and clorazepate (15 mg) were comparable, and each modified sleep for about 28-30 h after ingestion. 4 With nordiazepam (10 mg) and clorazepate (15 mg) the subjects, as a group, reported improved sleep, but subjective assessments of well-being were not altered. Correlations were calculated for sleep measures and subjective assessments.

Adult↗