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Biomedical subjects

A H Riesen

Publications and source records attributed to A H Riesen.

4 recordsLinked to original sources
PubMed1979

Effects of the duration of dark rearing on visually guided behavior in the kitten.

Forty-eight kittens were dark reared or light reared from birth for 1 to 8 months and formed 6 age groups. Following rearing the kittens were examined daily in several tasks of visually guided behavior. Compared to younger dark-reared groups of kittens, older deprived groups showed longer acquisition times for visual placing to a surface, visual tracking, visually guided reaching to a serrated edge and moving object, and visually guided locomotion on elevated platforms. After dark rearing durations of 3 months or longer, deprived groups displayed overall deficiencies in obstacle avoidance during their 1st postdeprivation month. The older dark-reared groups gave some indication of a direct relationship between duration of dark rearing and both delay in acquisition times for the visually guided behaviors and deficiency in obstacle avoidance. One interpretation of the results is that during dark rearing the kitten may acquire nonvisual behaviors which could interfere with and prolong its development of visually guided behavior subsequent to deprivation.

Animals↗
PubMed1978

Changes in cortical dendritic branching subsequent to partial social isolation in stumptailed monkeys.

Stumptailed monkeys were reared from 1 week after birth to 6 months of age in either a colony condition with the mother or in partial social isolation that allowed visual contact with the colony animals, but not physical contact. At 6 months of age the animals were killed and selected areas of the neocortex stained by the Golgi-Cox method. Relatively nonspiney cells of Layer IV were drawn and analyzed for complexity of dendritic branching. Isolation-reared animals had significantly decreased branching complexity in Motor I cortex when compared to the control animals. A transform of the data that related the number of branches to the number of previous branches showed a slight rearing effect in Somatosensory I cortex with the deprived animals having a lower rate of branching than the controls. We conclude that social isolation also includes a motoric deprivation that could account for these data.

Animals↗