A Level Psychology OCR Practice Exam

What procedure was used by Sperry et al (1968) to test participants' responses?

1. Participants were asked to recall images after a delay

2. Participants were seated in front of a screen while images flashed for a very short time

3. Participants completed a series of written questionnaires

4. Participants engaged in discussions about their perceptions

The correct answer is: Participants were seated in front of a screen while images flashed for a very short time

The procedure used by Sperry et al. (1968) involved participants being seated in front of a screen while images were presented for a brief period. This method was significant because it allowed researchers to investigate the functioning of the brain's hemispheres in individuals who had undergone a corpus callosotomy, a surgical procedure that disconnects the two hemispheres of the brain. By flashing images very quickly on the screen, often to just one visual field, Sperry could assess how each hemisphere processed information independently. This approach was particularly effective in exploring lateralization of brain function, where the left hemisphere is typically associated with language processing and the right hemisphere with spatial and visual tasks. The short duration of the images ensured that participants could not look for additional context or rely on memory to respond, providing insight into the immediate processing capabilities of each hemisphere, which was central to the study’s aims. In contrast, recalling images after a delay would rely on memory processes that were not the focus of Sperry's experiment. Completing written questionnaires and engaging in discussions about perceptions would not provide the same direct investigation of hemispheric function and would rather gather subjective data rather than assessing visual processing directly.