A primary function of the brain is to adaptively use past experience to generate expectations aboutevents that are likely to occur in the future. Lee et al. have used a machine learning model to analyze fMRI measurents made on 30 individuals as they watched repeated viewing of a movie, and a nice summary of this work is presented by the PNAS Journal Club. Areas in the frontal cortex anticipate (possibly foreseeing movie plot changes) up to 15 seconds in advance, while back of the brain cortical areas only anticipate about 1 second ahead. Frontal regions of the brain can keep track of tens of seconds, compared to only a few seconds at the back of the brain.
Vertical slices of the brain, imaged at different locations, reveal a timescale gradient for anticipation. Timescales are short at the back of the brain (cool blues) and longer at the front (warm reds).
These results demonstrate a hierarchy of anticipatory signals in the human brain and link them to subjective experiences of events...This hierarchical view of the brain is very different from the traditional, modular view,...In the traditional view, there are systems that process raw sensory inputs, such as sights or sounds, and there are separate systems that call up memories or make plans. The latest findings blur the lines between those systems, showing that regions known for processing simple pieces of visual information, such as the visual cortex, can also anticipate what’s coming up soon, even if just by a few seconds.
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