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Updated: May 22, 2026
08:59
Horizontal Hippocampal Slices of the Mouse Brain
Published on: September 22, 2020
Unconscious relational inference recruits the hippocampus
Thomas P Reber1, Roger Luechinger, Peter Boesiger
1Department of Psychology, University of Bern, 3012 Bern, Switzerland.
Summary
Unconscious relational inference, the ability to link memories, recruits the hippocampus. This process influences decision-making even without conscious awareness.
Area of Science:
- Cognitive Neuroscience
- Neurobiology of Memory
Background:
- Relational inference is crucial for updating knowledge and decision-making.
- It is traditionally believed to require both hippocampal function and conscious awareness.
Purpose of the Study:
- To investigate whether relational inference can occur outside of conscious awareness.
- To determine the role of the hippocampus in unconscious relational inference.
Main Methods:
- Participants (young, healthy men) were presented with subliminal word pairs with overlapping or non-overlapping elements.
- Reaction times during unconscious encoding and subsequent semantic relatedness judgments were recorded.
- Hippocampal activity was measured using fMRI during encoding and retrieval tasks.
Main Results:
- Unconscious relational inference effects were observed in reaction times and decision outcomes.
- Increased hippocampal activity correlated with the unconscious encoding of overlapping word pairs and retrieval of related words.
- Hippocampal activity during unconscious encoding predicted subsequent decision-making outcomes.
Conclusions:
- Relational inference can occur outside of conscious awareness.
- The hippocampus plays a role in unconscious relational inference.
- Unconscious inference processes can influence future decision-making.
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