Back

Noradrenaline causes a spread of association in the hippocampal cognitive map

Koolschijn, R. S.; Browning, M.; Clarke, W. T.; O'Reilly, J. X.; Barron, H. C.

2024-09-01 neuroscience
10.1101/2024.08.31.610602 bioRxiv
Show abstract

The mammalian brain stores relationships between items and events in the world as cognitive maps in the hippocampal system. However, the neural mechanisms that control cognitive map formation remain unclear. Here, using a double-blind study design with a pharmacological intervention in humans, we show that the neuromodulator noradrenaline elicits a significant spread of association across the hippocampal cognitive map. This neural spread of association predicts overgeneralisation errors measured in behaviour, and is predicted by physiological markers for noradrenergic arousal, namely an increase in the pupil dilation response and reduced cortical GABAergic tone. Thus, noradrenaline sets the width of the smoothing kernel for plasticity across the cognitive map. Elevated noradrenaline can allow disparate memories to become linked, introducing potential for distortions in the cognitive map that deviate from direct experience. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=137 HEIGHT=200 SRC="FIGDIR/small/610602v3_ufig1.gif" ALT="Figure 1"> View larger version (45K): org.highwire.dtl.DTLVardef@85d4ceorg.highwire.dtl.DTLVardef@564073org.highwire.dtl.DTLVardef@a16111org.highwire.dtl.DTLVardef@ebe1fc_HPS_FORMAT_FIGEXP M_FIG C_FIG

Published in Nature Communications (predicted rank #2) · training set

Matching journals

The top 2 journals account for 50% of the predicted probability mass.

50% of probability mass above

"Similar papers" are the closest papers from that journal in the model's embedding space. They show what the match is built on, but the ranking comes mostly from a classifier over the whole training set, not from these examples alone.