Visual evoked potentials during stimulus selection in eyelid conditioning in the rabbit (Oryctolagus cunigulus).

Abstract

Rabbit eyeblinks were conditioned to either the visual or the nonvisual element of a compound conditioned stimulus. Evoked potentials (EPs) were simultaneously recorded from the visual cortex. Changes in the late negative component of the EP were related to nonspecific arousal effects. The initial surface positive component, however, was significantly enhanced during visual stimulus control. This enhancement was observed whether the visual stimulus was presented alone or in compound and with either photic or optic chiasma stimulation as the visual stimulus. The effect could not be attributed to arousal, sensitization, or to peripheral mechanisms. Some implications of the data were assessed through a subsequent investigation of geniculostriate recovery cycles under the same conditions.

Giving flesh to a "straw man": A reply to Feeney, Pittman, and Wagner.

“…Moreover, the observation of Bear It should also be emphasized that the present authors recognize the possibility of specific as well as nonspecific influences on neurons at lower levels in the hierarchy. Work from our laboratory has shown that during attention to visual stimuli there is a specific enhancement of visual cortical evoked potentials, which cannot be attributed to changes in arousal (Kinkaide & Walley, 1974). However, in contrast to Feeney et al, we do not feel that such a mechanism is sufficient to account for selective attention.…”

Specific and nonspecific changes in visual evoked potentials during eyelid conditioning in the rabbit (Oryctolagus cuniculus).

“…As described earlier (Kinkaide & Walley, 1974), the cortical response evoked by optic chiasma stimulation consists of two or three surface positive waves (PI, P2, and P3) followed by a large slow surface negative wave (N3) reaching a peak between 100 and 200 Figure 3 shows the mean percentage changes in amplitude for PI (dark bars) and N3 (double cross-hatched bars) relative to the pretest baseline for the seven test sessions in which V was presented alone. For PI and the geniculate AEPs, the V-alone condition was used as a baseline.…”

“…The apparatus and the surgical and recording procedures have been described elsewhere (Kinkaide, 1974;Kinkaide & Walley, 1974) and are only summarized here. Departures from these earlier studies are described in detail.…”

“…These results were attributed to the nonspecific effects of conditioned fear . Kinkaide and Walley (1974) recorded EPs from the rabbit visual cortex during eyelid conditioning, using the blocking paradigm (Kamin, 1969) to control for nonspecific effects. The animals were initially given a series of differential conditioning trials with an auditory and a tactile stimulus.…”

“…The major aim of the parent study was to determine whether the above changes in PI could be attributed to changes in lateral geniculate excitability. This was accomplished by recording both cortical and lateral geniculate EPs under essentially the same procedures employed by Kinkaide and Walley (1974). In addition, recovery cycles were determined by varying the interval between pairs of pulses to the optic chiasma and recording the EPs produced by the second pulse.…”