Yasufumi Shiihara

Sleep–wake rhythm during stay in an intensive care unit: A week’s long-term recording of skin potentials

To monitor the sleep–wake cycle of patients during their stay in the intensive care unit (ICU), we tried continuous and long‐term recording of skin potential (SP) levels in patients after surgery. A graph of the week‐long SP showed the sleep–wake pattern to be evident until the fourth day. It disappeared beginning on the fifth day, resulting finally in delirium with a relatively high mean SP level. In another record, the administration of sedative agents to calm the excitement lowered the mean SP level and suppressed SP responses evoked by frequent day and night treatment or nursing care. Continuous monitoring of arousal level by SP will be of help in prevention of ICU syndrome.

Evaluation of sleep using ambulatory skin potential recording : Differences between morning and evening type

Abstract In order to validate the evaluation of sleep using cassette type ambulatory skin potential measurement system (C‐SPA), sleep duration variables extracted from 24 h recordings were compared between two groups (16 of the intermediate type and 16 of the evening type) with different sleep‐wake habits rated by Morningness and Eveningness Questionnaires (MEQ). Compared with the intermediate type, the evening type subjects go to bed and get up later, have difficulty in falling asleep and more frequently awaken during sleep. Thus, the sleep variables by C‐SPA provide valuable information about duration of sleep and differentiate the Sleep‐wake habits.

Continuous recordings of skin conductance change during sleep

Using a new compact and stable device, skin conductance change (SCC) was measured in five female undergraduates during sleep. The SCC trends and waveforms were almost identical to those of simultaneously recorded skin potential activity (SPA). A gradual increase in sympathetic sweating during sleep was also observed using SCC. However, the confounding effects of a burst of positive skin potential responses usually seen in SPA were absent using SCC.

Universality of Bereavement Life Review for Spirituality and Depression in Bereaved Families

The present study aimed to investigate the effects of the Bereavement Life Review on depression and spiritual well-being of bereaved families in a setting that does not specialize in palliative care. The participants were 20 bereaved family members who underwent the Bereavement Life Review over 2 sessions in 2 weeks. Beck Depression Inventory Second Edition scores significantly decreased from 14.4 ± 9.2 to 11.6 ± 7.4 (t = 2.15, P = .045) and Functional Assessment Chronic Illness Therapy–Spiritual scores increased from 24.3 ± 10.1 to 25.9 ± 11 (t = −1.0, P = .341) from pre- to postintervention. These results show that the Bereavement Life Review can decrease depression and improve spiritual well-being of bereaved families after the death of a family member in a setting without specialized palliative care. The results also suggest the universality of this therapy.

Use of ambulatory skin conductance recording for monitoring psychophysiological arousal in the elderly staying in care facilities

Abstract To monitor the psychophysiological arousal level in the elderly, 24 h recordings of skin conductance change (SCC) were done during their stay in care facilities. The mean and maximum SCC levels in 17 awake elderly subjects were significantly lower than those of levels in 20 healthy, young control subjects (P < 0.05 and P < 0.001, respectively). The mean SCC levels during sleep did not differ between groups. The SCC trend graph reflected a degree of daily activity. The daytime SCC profile of elderly individuals who could walk independently was comparable to that of healthy young subjects. In contrast, the SCC profile of the bedridden elderly were generally flattened with poor SCC responses that were evoked only by nursing procedures.

Skin blood flow responses during sleep by laser Doppler flowmetry

Skin surface blood flow at the fingertips was measured in a 21‐year‐old woman during sleep using laser Doppler flowmetry. Skin blood flow responses (SBFR) are transient reductions in skin blood flow of about 25 s in duration. In our subject, SBFR showed a delay time of 8–9 s from the onset of skin potential responses (SPR) and appeared more consistently than SPR. The frequency of SBFR decreased during non‐rapid eye movement sleep, especially when the sleep stage became deep. These findings indicate the validity of SBFR as a discrete index of autonomic function during sleep.

Aberrant judgmental pattern of schizophrenic patients in weight discrimination

Sixteen chronic schizophrenics and 16 normal controls were tested on a weight discrimination task in various categories and hand conditions. Schizophrenics made significantly more errors than normals when the ‘equal’ category was included, whereas schizophrenics’ performance could approximate the normals’ discriminations when the ‘equal’ category was excluded. In the former condition, the more inaccurate performance of schizophrenics was ascribed to the selective increase in the errors by the ‘equal’ judgments, which was not due to an increase in ‘doubtful’ judgments. These findings were assumed to reflect schizophrenics’ preference to equal judgments, which seemed to be their fundamental cognitive attitude, because the same tendency was found on the various discrimination tasks of other sensory modalities. Furthermore, the present results supported neither left hemisphere dysfunction nor interhemispheric transfer deficit in schizophrenia, because schizophrenics failed to show consistently more errors in the right hand and the bimanual conditions.

Muscle activation patterns in acceleration-based phases during reach-to-grasp movement

[Purpose] An earlier study divided reaching activity into characteristic phases based on hand velocity profiles. By synchronizing muscle activities and the acceleration profile, a phasing approach for reaching movement, based on hand acceleration profiles, was attempted in order to elucidate the roles of individual muscle activities in the different phases of the acceleration profile in reaching movements. [Subjects and Methods] Ten healthy volunteer subjects participated in this study. The aim was to electromyographically evaluate muscles around the shoulder, the upper trapezius, the anterior deltoid, the biceps brachii, and the triceps brachii, most of which have been used to evaluate arm motion, as well as the acceleration of the upper limb during simple reaching movement in the reach-to-grasp task. [Results] Analysis showed the kinematic trajectories of the acceleration during a simple biphasic profile of the reaching movement could be divided into four phases: increasing acceleration (IA), decreasing acceleration (DA), increasing deceleration (ID), and decreasing deceleration (DD). Muscles around the shoulder showed different activity patterns, which were closely associated with these acceleration phases. [Conclusion] These results suggest the important role of the four phases, derived from the acceleration trajectory, in the elucidation of the muscular mechanisms which regulate and coordinate the muscles around the shoulder in reaching movements.