eprintid: 1378392 rev_number: 32 eprint_status: archive userid: 608 dir: disk0/01/37/83/92 datestamp: 2012-12-01 20:15:15 lastmod: 2021-10-19 22:23:07 status_changed: 2012-12-01 20:15:15 type: article metadata_visibility: show item_issues_count: 0 creators_name: Cui, X creators_name: Stetson, C creators_name: Montague, PR creators_name: Eagleman, DM title: Ready...go: Amplitude of the FMRI signal encodes expectation of cue arrival time. ispublished: pub divisions: UCL divisions: B02 divisions: C07 divisions: D07 keywords: Brain, Cues, Humans, Magnetic Resonance Imaging, Models, Psychological, Motor Activity, Probability, Reaction Time, Time Factors note: © 2009 Cui et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. PMCID: PMC2711330 abstract: What happens when the brain awaits a signal of uncertain arrival time, as when a sprinter waits for the starting pistol? And what happens just after the starting pistol fires? Using functional magnetic resonance imaging (fMRI), we have discovered a novel correlate of temporal expectations in several brain regions, most prominently in the supplementary motor area (SMA). Contrary to expectations, we found little fMRI activity during the waiting period; however, a large signal appears after the "go" signal, the amplitude of which reflects learned expectations about the distribution of possible waiting times. Specifically, the amplitude of the fMRI signal appears to encode a cumulative conditional probability, also known as the cumulative hazard function. The fMRI signal loses its dependence on waiting time in a "countdown" condition in which the arrival time of the go cue is known in advance, suggesting that the signal encodes temporal probabilities rather than simply elapsed time. The dependence of the signal on temporal expectation is present in "no-go" conditions, demonstrating that the effect is not a consequence of motor output. Finally, the encoding is not dependent on modality, operating in the same manner with auditory or visual signals. This finding extends our understanding of the relationship between temporal expectancy and measurable neural signals. date: 2009-08-04 official_url: http://dx.doi.org/10.1371/journal.pbio.1000167 vfaculties: VFBRS oa_status: green language: eng primo: open primo_central: open_green article_type_text: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't verified: verified_manual elements_source: PubMed elements_id: 835252 doi: 10.1371/journal.pbio.1000167 lyricists_name: Montague, Pendleton Read lyricists_id: RMONT72 full_text_status: public publication: PLoS Biology volume: 7 number: 8 article_number: e1000167 pagerange: - event_location: US issn: 1554-9173 citation: Cui, X; Stetson, C; Montague, PR; Eagleman, DM; (2009) Ready...go: Amplitude of the FMRI signal encodes expectation of cue arrival time. PLoS Biology , 7 (8) , Article e1000167. 10.1371/journal.pbio.1000167 <https://doi.org/10.1371/journal.pbio.1000167>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/1378392/1/1378392.pdf