Adaptive behavior requires the separation of current from future goals in working memory. We used fMRI of object-selective cortex to determine the representational (dis)similarities of memory representations serving current and prospective perceptual tasks. Participants remembered an object drawn from three possible categories as the target for one of two consecutive visual search tasks. A cue indicated whether the target object should be looked for first (currently relevant), second (prospectively relevant), or if it could be forgotten (irrelevant). Prior to the first search, representations of current, prospective and irrelevant objects were similar, with strongest decoding for current representations compared to prospective (Experiment 1) and irrelevant (Experiment 2). Remarkably, during the first search, prospective representations could also be decoded, but revealed anti-correlated voxel patterns compared to currently relevant representations of the same category. We propose that the brain separates current from prospective memories within the same neuronal ensembles through opposite representational patterns.
- Christian N L Olivers
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: Human subjects: Twenty-four healthy volunteers participated in Experiment 1 and twenty-five healthy volunteers participated in Experiment 2. The experiment was approved by the Ethical Committee of the Faculty of Social and Behavioral Sciences, University of Amsterdam and conformed to the Declaration of Helsinki. All subjects provided written informed consent and consent to publish.
- Floris de Lange, Donders Institute for Brain, Cognition and Behaviour, Netherlands
© 2018, van Loon et al.
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