TY  - JOUR
PY  - 1981//
TI  - Ultradian rhythms in stereotyped and self-injurious behavior
JO  - American journal of mental deficiency
A1  - Lewis, M. H.
A1  - MacLean, William E.
A1  - Johnson, W. L.
A1  - Baumeister, A. A.
SP  - 601
EP  - 610
VL  - 85
IS  - 6
N2  - Institutionalized profoundly mentally retarded persons who exhibited stereotyped motor movements, including self-injurious behavior, were observed continuously in their typical environments for periods of 8 to 14 hours on each of several days. In addition to targeting stereotyped responses, we collected data pertaining to activities, settings, other behavioral states, and social interactions. Spectral and cross-spectral analyses were conducted on data from each daily session. Power spectra indicated a marked ultradian or less than 24-hour rhythm for each subject on each day. Spectral density estimates were thought to reflect the influence of rhythmic changes in the institutional environment and, to a less degree, the influence of an endogenous rest--activity rhythm.<p /> <p>Language: en</p> 
LA  - en
SN  - 0002-9351
UR  - http://dx.doi.org/
ID  - ref1
ER  -