RT Journal Article
SR Electronic
T1 Neural evidence for boundary updating as the source of the repulsive bias in classification
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2023.01.11.523692
DO 10.1101/2023.01.11.523692
A1 Heeseung Lee
A1 Hyang-Jung Lee
A1 Kyoung Whan Choe
A1 Sang-Hun Lee
YR 2023
UL http://biorxiv.org/content/early/2023/01/13/2023.01.11.523692.abstract
AB Binary classification, an act of sorting items into two classes by setting a boundary, is biased by recent history. One common form of such biases is repulsive bias, a tendency to sort an item into the class opposite to its preceding items. Sensory-adaptation and boundary-updating are considered as two contending sources of the repulsive bias, yet no neural support has been provided for either source. Here we explored human brains, using fMRI, to find such supports by relating the brain signals of sensory-adaptation and boundary-updating to human classification behavior. We found that the stimulus-encoding signal in the early visual cortex adapted to previous stimuli, yet its adaptation-related changes were dissociated from current choices. Contrastingly, the boundary-representing signals in the inferior-parietal and superior-temporal cortices shifted to previous stimuli and covaried with current choices. Our exploration points to boundary-updating, rather than sensory-adaptation, as the origin of the repulsive bias in binary classification.Competing Interest StatementThe authors have declared no competing interest.