Influence of biased feedback on performance in a Vernier discrimination task

Area of Science:

• Cognitive Psychology
• Neuroscience
• Psychophysics

Background:

• The impact of feedback on performance is debated, with studies showing inconsistent helpful, harmful, or ineffective results.
• Feedback may create conflict between internal beliefs and external sensory information, potentially explaining varied outcomes.
• Biased feedback, incongruent with a subject's choices, is hypothesized to induce this conflict.

Purpose of the Study:

• To investigate the influence of biased feedback on performance using a Vernier discrimination task.
• To examine how trial-by-trial versus block feedback affects performance and learning.
• To determine if biased feedback impacts signal or noise discrimination differently.

Main Methods:

• A Vernier discrimination task was employed to assess visual perception of offset stimuli.
• Experiment 1: Trial-based feedback, with biased feedback for small/medium offsets.
• Experiment 2: Block-based feedback; Experiment 3: Modified block feedback without large offsets to isolate signal/noise effects.

Main Results:

• Biased feedback, whether trial-based or block-based, decreased accuracy for the target Vernier.
• Performance improved in the absence of feedback, indicating feedback's detrimental effect when biased.
• Large stimulus differences promoted encoding learning over decision learning; low discrimination made noise discrimination more vulnerable to biased feedback.

Conclusions:

• Biased feedback negatively impacts performance in perceptual tasks by creating conflict.
• The absence of feedback can be beneficial when biased feedback is present.
• Biased feedback affects encoding and decision learning, with noise discrimination being particularly susceptible.