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Scheduling error Our officially scheduled final exam period is Saturday at 10:30 a.m. We put Monday at 7:30 a.m. on the syllabus. We still plan to hold the Monday session, beginning at 8:30. If you cannot make it on Monday morning and you want to give an extra-credit presentation, please let me know. We can have an additional session on Saturday. View animation from Heider and Simmel Martin and Weisberg Methodology: Four different kinds of animations Social vignettes (for example, sharing ice cream) Mechanical vignettes (for example, conveyor belt moving) Random movement (using same shapes used in the other displays) Still (no motion) Subjects view displays while in the fMRI magnet. Subjects are highly accurate in their multiple-choice identification of animation themes during fMRI. Subjects have no trouble recognizing, for example, sharing of ice cream as the right answer even when other closely related answers are provided. Results Distinctively social areas: Lateral Fusiform Gyrus Right Superior Temporal Sulcus (STS) Right Anterior STS Amygdala Ventromedial Prefrontal Cortex Fusiform Gyrus (pink) Superior Temporal Sulcus (red) Amygdala (red bulb) Ventromedial Prefrontal Cortex (VMPFC) Distinctively mechanical areas: --Medial Fusiform Gyrus --Left Middle Temporal Gyrus Standard Intro to the Brain Conditions for a Representation’s Being Modally Specific --is realized (i.e., takes physical form) in primary sensory cortex? --should we include secondary sensory areas? How are sensory areas determined, anyway? Where Should We Expect Amodal Symbols to Be in the Brain? Look for areas that are active when we engage in “abstract” reasoning, for example, logical deduction or decisionmaking in the absence of related sensory input. (What about naming?) And whatever activity we find must be the realizer (the physical form) of an amodal symbol? That approach seems too simplistic. What if we find some of this activity in areas that were previously thought to be specific to a sensory modality? How should we reason in response? Two possibilities: 1. We found the physical realizers of what we thought were amodal symbols, and it turns out that they’re in the sensory cortex; therefore, there are no amodal symbols, only modally specific ones. OR 2. We found the physical realizers of what we thought were amodal symbols, and it turns out that they’re in what we used to think was sensory cortex; now we know that such cortex is not entirely devoted to modally specific processing. In other words, do we change our conception of the symbols, or do we change our conception of the cortex? Similarly, what if sensory stimuli cause activation in areas that are not so directly related to what we thought were modally specific areas? Two possible reactions: 1. The activity is occurring in nonsensory cortex, so the symbols appearing in that part of cortex are not modally specific. The activation of modally specific representations (realized in genuinely sensory cortex) causes the activation of associated amodal symbols. OR 2. We expand what counts as sensory cortex and hold that the activation observed in response to sensory stimulus is the physical form of only one (perhaps neurally distributed) sensory symbol. What drives the decision of one response over the other? Take the ventromedial prefrontal activation in response to social vignettes. This active area is known to regulate emotion and social communication. Should this be considered part of the very representation of people or merely the activity of a mechanism that affects the processing of thoughts about people?