Why the "stimulus-error" did not go away.
Studies in history and philosophy of science April 1, 2016 Peer reviewed DOI: 10.1016/j.shpsa.2015.10.007 via PubMed
Summary
The stimulus-error—when subjects in introspective experiments report based on knowledge of the stimulus rather than raw perceptual experience—was a key methodological concern for early psychologists like Titchener and Boring. Though behaviorism made their theoretical assumptions unfashionable, the issue remains relevant because subjects give different perceptual reports to the same stimulus. Contemporary work on color and lightness constancy still grapples with which reports are legitimate, often without using the term. The debate reveals deep theoretical commitments about sensation and the perception-cognition boundary, with implications for current philosophy of perception.
Study at a glance
| Design | theoretical or philosophical paper |
|---|---|
| Key finding | Concern over the stimulus-error persists in contemporary psychophysics and reveals psychologists' deep theoretical commitments about sensation and the perception-cognition boundary. |
Abstract
Psychologists in the early years of the discipline were much concerned with the stimulus-error. Roughly, this is the problem encountered in introspective experiments when subjects are liable to frame their perceptual reports in terms of what they know of the stimulus, instead of just drawing on their perceptual experiences as they are supposedly felt. "Introspectionist" psychologist E. B. Titchener and his student E. G. Boring both argued in the early 20th century that the stimulus-error is a serious methodological pit-fall. While many of the theoretical suppositions motivating Titchener and Boring have been unfashionable since the rise of behaviourism, the stimulus-error brings our attention to one matter of perennial importance to psychophysics and the psychology of perception. This is the fact that subjects are liable to give different kinds of perceptual reports in response to the same stimulus. I discuss attempts to control for variable reports in recent experimental work on colour and lightness constancy, and the disputes that have arisen over which kinds of reports are legitimate. Some contemporary psychologists do warn us against a stimulus-error, even though they do not use this terminology. I argue that concern over the stimulus-error is diagnostic of psychologists' deep theoretical commitments, such as their conception of sensation, or their demarcation of perception from cognition. I conclude by discussing the relevance of this debate to current philosophy of perception.