Investigating the Affective Consequences of Cognitive Control for Visual Stimuli: Prevalence and Underlying Mental Representations
Items that have been ignored or from which a response is withheld subsequently receive more negative affective evaluations than other comparable stimuli, whereas prior targets of attention/response often receive more positive affective evaluations than other comparable stimuli. These effects are thought to reflect the negative or positive impact, respectively, on the coding of stimulus-associated value that occurs during inhibition or amplification of neurocognitive representations of stimuli/responses based on their relevance to current and long-term goals. Although such effects have been observed for various types of stimuli and affective judgements following a wide range of attention-, response-, and memory-related tasks, the full range of situations in which the affective consequences of cognitive-control mechanisms emerge remains unknown. Also unknown is the full extent to which human feelings, thought and behaviour are guided by such interactions of cognitive control and emotion. The research presented here therefore builds on prior work in three related lines of investigation. In Chapter 1, I investigated the affective consequences of cognitive control in the important but previously-unexplored domain of task switching. I measured affective ratings of art-like patterns that previously appeared on critical trials of a task-switching paradigm (ABA vs. CBA task sequences) known for its capacity to demonstrate behavioural effects of inhibition. Stimuli from the ABA-sequence experimental condition showing behavioural evidence of backward inhibition (n-2 repetition costs) received more negative ratings than those from the CBA-sequence control condition. Inhibition applied during task switching therefore appears to have negative affective consequences just as it does in other tasks requiring cognitive inhibition. In Chapter 2, I combined selective-attention (visual-search) and selective-response (Go/No-go) tasks with an affective-evaluation task to elucidate the nature of the memory representations that track changes in the value of stimuli by testing two competing hypotheses about how the history and consistency of an item’s attention/response status determines its subsequent affective rating. The results provide support for the cumulative-history hypothesis, whereby stimulus ratings reflect the summed total of prior experience, critically depending on the proportion of trials in which an item has been attended/responded-to relative to those in which it has been ignored or associated with a suppressed response. In contrast, there was no evidence to support the recent-overwrite hypothesis, whereby the most recent experience with an item is the primary determinant of how much it is liked. In Chapter 3, I show that the simple act of not pressing a key during the perception of sexual content reduces its motivational incentive and subsequent capacity to elicit sexual arousal. Participants completed a Go/No-go task that required them to inhibit responses to either sexual or non-sexual images. Later they watched sexually explicit videos and reported moment-to-moment changes in self-reported sexual arousal, while thermography was used to record changes in genital physiological arousal. Participants who previously inhibited sexual images experienced lower levels of both self-reported and physiological arousal than those who inhibited non-sexual images. These results extend prior research to suggest that a by-product of motor-response inhibition is a negative alteration of stimulus-value representations for associated items— the kind of value that drives even the most biologically-fundamental forms of motivated behaviour. Taken together, the results of my dissertation research provide new knowledge about the nature of the representations underlying the affective consequences of cognitive control and show that it may be far more prevalent and impact a much wider range of human thought, feelings and behaviour than previously understood.