Reversible cortical depression and avoidance behavior in the rat.

Bilateral spreading depression and avoidance learning in rats

“…Bures has attributed this loss to a disturbance of cortical mechanisms involved in the learning process. Tapp (1962), on the other hand, reported a significant correlation between the loss of a conditioned avoidance habit and impaired sensorimotor co-ordination due to BSD. Tapp's evidence implies that stimulus and response complexity are important variables which may affect the performance of BSD animals in avoidance situations.…”

“…Functional cortical ablation produced by bilateral spreading depression (BSD) invariably results in impaired avoidance learning in rats (Bures, Buresova & Zahorva, 1958;Tapp, 1962;Travis & Sparks, 1963;Bures, 1959). Bures has attributed this loss to a disturbance of cortical mechanisms involved in the learning process.…”

Spreading depression: Effects of applying potassium chloride to the dura of the rabbit on the conditioned nictitating membrane response

“…It is also of interest to note that during the period of depression of CRs, the VCRs remained intact and showed no modification in response topography. More important perhaps, the regular occurrence of spontaneous membrane responses in the intertrial intervals during depreSSion, indicated the response was intact and further weakens the thesis of Tapp (1962) that the effects of KCl on learned behavior operates through impairment of S's motor coordination.…”

Interhemispheric spread and graded response in spreading cortical depression

“…However, Leao (1944) and Marshall (1959) report SD to be a graded response ranging from complete disappearance of the EEG to slight alterations in the pattern. Recent behavioral research (Tapp, 1962) also suggests that there is an analog relationship between KC1 concentration and behavioral deficit. The behavioral deficit and duration of the SD effect increased as a function of the KC1 concentration used.…”

“…However, the specific nature of SD remains elusive. Several learning investigators (Bures & Buresova,1963;Tapp, 1962;Travis & Sparks,1963) claim that unilate ral potassium chloride (KC1) application to the exposed, intact brain elicits only unilateral depression. On the other hand, Gollander & Ochs (1963) report that SD spreads interhemispherically following unilateral stimulation.…”