Neural response during preference and memory judgments for subliminally presented stimuli: a functional neuroimaging...

Area of Science:

• Cognitive Neuroscience
• Neuroimaging
• Psychology

Background:

• The mere exposure effect demonstrates that repeated exposure to stimuli enhances preference, even without conscious recognition.
• This phenomenon suggests an unconscious memory system influencing subjective judgments.
• Understanding the neural mechanisms underlying this effect is crucial for cognitive science.

Purpose of the Study:

• To investigate the neural mechanisms of the mere exposure effect using functional neuroimaging.
• To differentiate brain activity associated with explicit memory retrieval versus preference judgments.
• To explore the neural basis of implicit memory influencing aesthetic preferences.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to study nine healthy volunteers.
• Participants made forced-choice judgments on abstract stimuli based on preference or memory.
• Stimuli were presented either subliminally or as novel, with different judgment conditions.

Main Results:

• Memory judgments activated left frontopolar and parietal areas.
• Preference judgments engaged medial prefrontal and occipital cortex.
• Implicit memory's influence on preference correlated with right lateral frontal activation.
• Hippocampal gyrus responded to stimulus novelty irrespective of conscious report.

Conclusions:

• The brain exhibits distinct neural systems for explicit memory and preference-based judgments.
• Right lateral prefrontal cortex plays a role in implicit memory influencing preference.
• Hippocampal responses to novelty can occur independently of conscious familiarity.
• This study elucidates the neural underpinnings of unconscious influences on decision-making.