PubMed Health⌕ Search

Biomedical subjects

J W Doust

Publications and source records attributed to J W Doust.

14 recordsLinked to original sources
PubMed1979

Periodic homeostatic fluctuations of skin temperature in the sleeping and waking state.

53 healthly persons were monitored for skin temperature by a Hardy dermal radiometer every 60 sec. Readings continued until a spontaneous cycle appeared. 32 subjects were examined awake and 21 while asleep. A spontaneous rhythm with a mean of 4.25 min was found for the awake subjects, and one of 8.33 for the asleep subjects. To confirm these findings longer recordings were made by a thermocouple electronic thermometer in a further 23 subjects. Observations were continued until the awake subject slept. The results were analyzed by autocorrelation. In 13 records the sleeping rhythm was significantly longer than the waking. Another thermocouple probe in 14 subjects was used to measure axillary temperature. In 7 subjects a shorter cycle was seen while awake and a longer one while they slept. The properties of a perceptual clock are reviewed. It is suggested that the relative awareness of the subject be added to them.

Adolescent↗
PubMed1978

A free-running endogenous rhythm of the resting heart rate in man.

A sine-wave oscillating rhythm of the heart rate is reported in 24 out of 31 resting healthy subjects. Identification of these free-running cycles was by spectral analysis of minute-by-minute recordings of electrocardiograms, and in a few cases by inspection of cardiotachometer records. The periodicity of this rhythm was circa 10 min and was intermediate in frequency between the rapid fluctuations with frequencies of 15, 30, and 60 s and those of a frequency recurrent every 90 min already described in the literature. Our cycles were independent of age and sex.

Adolescent↗
PubMed1978

The diagnostic potential of rheoencephalography in psychiatry.

A 33 electrode monopolar rheoencephalograph was employed to produce a 15 min record of electrical impedance plethysmographic pulse-volume waves in 139 healthy sujects and 782 patients belonging to 15 psychiatric syndromes. Parameters of amplitude, percent rise time and average inflow angle were hand-measured and their means obtained for 30 waveforms throughout each record. Results obtained depended significantly upon chronological age and in some cases on gender. Mental health was found clearly distinguishable from psychiatric disability, but psychiatric syndromes could not be differentiated from one another. A low percent rise time coupled with a high average inflow angle were typical of youth and mental health.

Adolescent↗
PubMed1977

Carotid-vertebral artery blood transit time in health and in neurological patients: a preliminary study by a non-invasive impedance method.

Thirty-one healthy subjects and nineteen neurological patients covering a range of chronic neurological and neurovascular syndromes were examined by an electrical impedance method. Two estimates of carotid-vertebral artery transit times were measured: one time taken between the Q wave of the EKG to the commencement of the next succeeding impedance pulse-volume wave (CT1), and the other, this estimate together with the time to maximum point of the impedance wave (CT2). Results indicated prolonged circulation times for the patients as compared with the controls without relevance to age in the case of CT1, although transit times did increase with age for CT2. It is suggested that this impedance technique may be valuable in the initial screening of transient cerebral ischaemia.

Adolescent↗
PubMed1976

Characteristics of a neural clock regulating perception and psychomotor performance in man.

A biological clock regulating some psychomotor aspects of perception has been adduced from the results of the repetitive administration of a maximal speed tapping test of 15 sec per hand per min for a total of 20 min. 412 longitudinal timed tests from 8 healthy control subjects, 4 physically healthy and 6 brain damaged psychiatric patients formed the basis for the investigation of the properties of this clock. It was found that this perceptual clock is endogenous, self-sustaining and innate. Its free-running oscillations are independent of psychic state, emotions and affect. They are, however, dependent upon the subject's neural integrity and their phase may be influenced by an orientating reflex. Timing is precise but the preceding phase may influence a succeeding one. Despite the muscular activity of the task the clock is relatively independent of body temperature. It is also immune to most psychoactive drugs.

Adult↗
PubMed1976

Carotid-vertebral artery blood transit time: results in healthy subjects and patients with schizophrenia and brain disease.

Estimation of blood transit time in the neck and the extension of this into the head was made by a method of electrical impedance, over a wide age range, in 159 healthy subjects, 160 schizophrenic patients, and 199 patients with organic brain disease. In each case, the distance between the electrocardiogram and the next succeeding pulse-volume impedance wave was measured and averaged over 30 serial wave forms. Chronological age proved a significant variable, transit times lengthening progressively with the age, but only for measurements extending into the head. Sex and hemispheric laterality played no significant role. With age held constant, mean transit times into the head were significantly prolonged in both groups of patients as compared with controls. No significant differences were found however between means of psychiatric andneurological patients. It is suggested that these results reinforce the organic etiology of schizophrenia.

Adolescent↗
PubMed1975

Spontaneous rhythms of perceptual motor performance in intact and damaged brain of man.

A simple 15-sec maximal speed tapping task was administered every minute for 20 min to 69 healthy subjects and to 53 patients with mental disorders embodying six diagnostic categories including mental retardation. Analysis of the results showed age and diagnosis, but not gender, to be significant variables. Autocorrelation analysis of the results revealed the existence of spontaneous ultradian cycles of recurrence for all subjects, the frequency and amplitude of which discriminated the healthy subjects and only non-organically sick patients from patients with organic neurological deficits. 'Scatter' scores representing deviations about the mean tapping scores showed similar cyclic characteristics. The relationship between these cycles of motor performance and neural clock controlling perception is discussed.

Adolescent↗