Habituation of Stimulus-Elicited Involuntary Cognitions: Implications for Neuroimaging and Psychopathology
By: Sarah Brauer, Tala Elsabbagh, Dennis Lambert, and Sabrina Bhangal
Department: Psychology
Faculty Advisor: Dr. Ezequiel Morsella
Most of the contents of consciousness enter consciousness in an involuntary, reflexive manner. In one variant of the Reflexive Imagery Task (RIT), subjects are presented with visual objects and instructed to not subvocalize the names of these objects. Subjects often cannot suppress these subvocalizations. Knowledge of the boundary conditions of RIT effects illuminates the limitations of involuntary processes. Regarding boundary conditions, in a new analysis, we combined the data from two prior studies (n = 109) to corroborate that RIT effects can be decreased through the technique of habituation, in which the same stimulus is presented repeatedly (ten times). From the first instantiation to the tenth instantiation, the mean proportion of trials in which there was an RIT effect decreased systematically (SDs in parentheses): .73 (.25), .50 (.31), .42 (.33), .38 (.33), .37 (.35), .35 (.34), .36 (.34), .34 (.35), .34 (.35), .35 (.35). This paradigm is suitable for neuroimaging technologies that could identify the neural correlates of the habituation process. We examined whether the word frequency associated with the stimulus influences the nature of habituation. We discuss future directions of this “habituation” variant of the RIT, including (a) a study that measures the duration of stimulus-specific habituation and involves verbal associations that are learned only in the laboratory, and (b) an experiment designed to detect the habituation, not of subvocalizations, but of a higher-level task set (adding numbers). We discuss the implications of this variant of the RIT for neuroimaging and psychopathological phenomena, wherein involuntary cognitions can be debilitating.