Magnetoencephalographic Signals Identify Stages in Real-Life Decision Processes

[摘要] We used magnetoencephalography (MEG)to study the dynamics of neural responses ineight subjects engaged in shopping for day-to-dayitems from supermarket shelves. Thisbehavior not only has personal and economicimportance but also provides an example of anexperience that is both personal and sharedbetween individuals. The shopping experienceenables the exploration of neural mechanismsunderlying choice based on complex memories.Choosing among different brands of closelyrelated products activated a robust sequence ofsignals within the first second after the presentationof the choice images. This sequenceengaged first the visual cortex (80-100 ms),then as the images were analyzed, predominantlythe left temporal regions (310-340 ms).At longer latency, characteristic neural activetionwas found in motor speech areas (500-520ms) for images requiring low salience choiceswith respect to previous (brand) memory, andin right parietal cortex for high salience choices(850-920 ms). We argue that the neuralprocesses associated with the particular brand-choicestimulus can be separated into identifiablestages through observation of MEG responsesand knowledge of functional anatomy.

[学科分类] 精神健康和精神病学