AJP - Regulatory, Integrative and Comparative Physiology, Vol 241, Issue 5 312-R315, Copyright © 1981 by American Physiological Society
Cross-species invariance in state-related motility patterns
E. B. Thoman, L. P. Zeidner and V. H. Denenberg
Each of the sleep and wake states of animals are characterized by specific
patterns of behavioral, motoric, and electrophysiological activity.
Sleep-wake behavior of rats, rabbits, and human infants (3 of each species)
was observed, and, at the same time, a single-channel analog recording was
obtained of the motoric activity. A judge who had extensive experience in
observing sleep-wake behaviors of human infants, but who was unfamiliar
with these behaviors in nonhuman species, scored the analog signals of the
rats and rabbits. Another judge, who knew rat and rabbit state behaviors
well, but who had not had experience observing human infants, judged the
states of the human infants from the analog signals. These judgments were
evaluated by comparing them with the findings obtained from direct
observation of the subjects. For the nine subjects, the correlations
between the judges' scoring of the analog recording and direct observation
ranged from 0.856 to 0.985. A more stringent criterion is to determine the
exact agreement between judge and observer for each 10-s epoch during the
observation. For the major states of active sleep and quiet sleep, the
exact agreement ranged from 95.2 to 100%. The wake state was easily judged
for rats (100% agreement) but was more difficult for rabbits and humans
(59.9 and 66.7%, respectively). This ability to accurately score the state
behavior of an unfamiliar species from an analog movement record alone
represents a cross-species invariance in neuromotor organization. The
critical parameters appear to be regularity or irregularity of respiration
and the temporal distribution of gross motor movement.
