Essay Questions
1. What are the mechanisms underlying after-effects in the perceptual system? Do you think that these effects represent a fundamental flaw in the perceptual system, or could they have positive value in an evolutionary context?
Key Points:
- Consider the different varieties of after-effects that have been considered in this chapter.
- Consider the mechanisms by which processes of adaptation to environmental stimuli create the preconditions for the occurrence of after-effects.
- Credit awarded for students’ consideration of issues such as constancy and change, whereby consistent stimulation of specific channels and receptors can lead to a downgraded response in those receptors (the role of the central nervous system as a “change detection” system being one possible relevant consideration that the student could bring to bear in their discussion).
- Although after-effects may manifest as flaws in the perceptual system, credit given for a consideration of the extent to which after-effects represent a necessary consequence of the sensitivity of the perceptual system to environmental events.
- Additional credit could be awarded to the student who considers the operation of an ‘alternative’ perceptual system (such as might be developed by artificial intelligence researchers) and the possible downside of such an alternative system (which may or may not itself demonstrate perceptual after-effects).
