Attention, prediction and fMRI Class project: due Tues. April 29th April 29th: Just before start of “reading week” How long? • The shorter the better! Max. 6 pages Format? • Front-load the information • 1st sentence: What Q are you asking? • 2nd sentence: How are you going to ask it? • 3rd sentence: Why should the reader care? Class project: due Tues. April 29th Content? • Show that you have explored to find out what is currently known, what is unknown • Show that you have thought about what an interesting new direction to look would be • Describe in broad terms an expt which would look in that direction • State an explicit hypothesis • Describe explicitly how the data will test that hypothesis Give elevator pitch? What is attention? Obligatory William James quote: "Everyone knows what attention is. It is the taking possession by the mind in clear and vivid form, of one out of what seem several simultaneously possible objects or trains of thought...It implies withdrawal from some things in order to deal effectively with others, and is a condition which has a real opposite in the confused, dazed, scatterbrained state." Principles of Psychology(1890, p. 403) What is attention? (continued) Task relevance Related to consciousness? Is it a single “thing”? Can you pay attention to two things at once? Is it like a spotlight? What is expectation? We always have expectations about what will be happening next How do we form those expectations? What are they based on? How does the brain represent those expectations? Expectation, prediction and memory Traditional view of memory • The purpose of memory is to remember the past Prospective view of memory • The purpose of memory is to predict the future, using the past as a basis Two types of attention, and how to elicit them Posner task: Endogenous and exogenous attention Task-driven and stimulus-driven attention http://en.wikipedia.org/wiki/Posner_cueing_task Prediction and prediction errors http://www.scholarpedia.org/a rticle/Reward_signals Predictive coding Subtract expectations from bottom-up input Helmholtz, Mumford, Rao & Ballard, Friston Jehee & Ballard (2009) Top-down enhancement Kastner et al. (1999) Attention within a receptive field: Moran & Desimone (1985) Figure from http://kybele.psych.cornell.edu/~edelman/Psych4320/week-2.html Trying to pull apart attention and expectation Kok et al. 2012 Trying to pull apart attention and expectation: predictions Kok et al. 2012 Trying to pull apart attention and expectation: results Kok et al. 2012 Top-down feedback of information: Decoding the yellow of a gray banana Bannert & Bartels, 2013 Top-down feedback of information: Decoding the yellow of a gray banana Bannert & Bartels, 2013 Thursday: computer practical with Dan Cole Coding stimulus onsets in SPM Fitting a basic general linear model: which areas light up? Not the really interesting question, but a key step along the way!