The orienting response and stimulus significance: further comments

Area of Science:

• Cognitive Psychology
• Neuroscience
• Psychophysiology

Background:

• The significance hypothesis of orienting responses (OR) has faced criticism regarding its basis and replicability.
• Previous critiques suggested the hypothesis relied on tautological arguments and intensity decrease effects.

Purpose of the Study:

• To refute Siddle's (1979) criticisms of the significance hypothesis.
• To clarify the empirical support for the significance hypothesis based on subsequent research.
• To differentiate the significance hypothesis from alternative explanations like response stereotypy and trait-lability.

Main Methods:

• Review of studies testing specific predictions derived from the significance hypothesis.
• Analysis of data demonstrating differential responses to significant versus nonsignificant novelty.
• Examination of group differences in OR components and their relation to stimulus assessment.

Main Results:

• Empirical evidence from multiple laboratories supports the significance hypothesis.
• The hypothesis does not depend on intensity decrease, and claims of nonreplicability are unfounded.
• Data show differential ORs to significant novelty and consistent group differences, challenging response stereotypy and trait-lability arguments.

Conclusions:

• The significance hypothesis posits that OR components reflect higher-level processing of significant, organism-relevant information.
• ORs are elicited after detecting uncertainty and significance, not solely as automatic responses.
• The distinction between voluntary and involuntary attention is acknowledged, but OR components' assignment to involuntary attention is questioned due to long latencies and stimulus-specific responses.