Food wrenching and dodging: a neuroethological test of cortical and dopaminergic contributions to sensorimotor behavior in the rat.
Sensorimotor behavior in unilateral decorticate and unilateral dopamine-depleted rats was studied in a naturally occurring social interaction in which rats compete for food with relatively stereotyped species-typical responses. In the interaction a "robber" attempts to wrest food from a feeding "victim," which in turn protects the food by making rapid contralateral dodges. Hemidecortication abolished dodging to food wrenching attempts made by a rat approaching contralaterally to the lesion, so that the food was stolen, but recovery occurred between 15 and 60 days after surgery. Use of the side contralateral to the lesion to wrest food was moderately impaired, and recovery of food wresting was more rapid than recovery of dodging. There were no impairments in dodging to approaches to the side of the body ipsilateral to the lesion, nor were there impairments in using that side of the body to wrest food from other rats. Unilateral dopamine depletion produced dodging impairments to food-wresting attempts that were made both ipsilateral and contralateral to the side of the lesion, and the deficits endured over 60 test days. The food was frequently lost to food-wrenching attempts made contralateral to the lesion, whereas the direction of dodges to approaches ipsilateral to the lesion was reversed. Food wresting was also bilaterally impaired. In conclusion, the study shows (a) there are differences in the sensorimotor impairments that follow unilateral neocortical damage and unilateral dopamine depletion, (b) the neural organization of orienting and dodging is different, and (c) the form of the sensorimotor impairments as well as the processes of recovery can be usefully analyzed by using species-typical social interactions.
D000818:Animals; D001070:Appetitive Behavior; D002540:Cerebral Cortex / Q000502:physiology*; D003342:Corpus Striatum / Q000502:physiology; D004298:Dopamine / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006892:Hydroxydopamines; D016627:Oxidopamine; D051381:Rats; D012016:Reference Values; D013239:Stereotyped Behavior; D013997:Time Factors
D006892:Hydroxydopamines; D016627:Oxidopamine; D004298:Dopamine