What Is the Effect of Basic Emotions on Directed Forgetting? Investigating the Role of Basic Emotions in Memory

Abstract

Studies presenting memory-facilitating effect of emotions typically focused on affective dimensions of arousal and valence. Little is known, however, about the extent to which stimulus-driven basic emotions could have distinct effects on memory. In the present paper we sought to examine the modulatory effect of disgust, fear, and sadness on intentional remembering and forgetting using widely used item-method directed forgetting (DF) paradigm. Eighteen women underwent fMRI scanning during encoding phase in which they were asked either to remember (R) or to forget (F) pictures. In the test phase all previously used stimuli were re-presented together with the same number of new pictures and participants had to categorize them as old or new, irrespective of the F/R instruction. On the behavioral level we found a typical DF effect, i.e., higher recognition rates for to-be-remembered (TBR) items than to-be-forgotten (TBF) ones for both neutral and emotional categories. Emotional stimuli had higher recognition rate than neutral ones, while among emotional those eliciting disgust produced highest recognition, but at the same time induced more false alarms. Therefore, when false alarm corrected recognition was examined the DF effect was equally strong irrespective of emotion. Additionally, even though subjects rated disgusting pictures as more arousing and negative than other picture categories, logistic regression on the item level showed that the effect of disgust on recognition memory was stronger than the effect of arousal or valence. On the neural level, ROI analyses (with valence and arousal covariates) revealed that correctly recognized disgusting stimuli evoked the highest activity in the left amygdala compared to all other categories. This structure was also more activated for remembered vs. forgotten stimuli, but only in case of disgust or fear eliciting pictures. Our findings, despite several limitations, suggest that disgust have a special salience in memory relative to other negative emotions, which cannot be put down to differences in arousal or valence. The current results thereby support the suggestion that a purely dimensional model of emotional influences on cognition might not be adequate to account for observed effects.

Dynamic Changes in Amygdala Psychophysiological Connectivity Reveal Distinct Neural Networks for Facial Expressions of Basic Emotions

“…For example, disgusting stimuli enhance episodic memory and seem to have a special salience in memory relative to other equally arousing and negative emotions, such as fear9394. Moreover, a recent fMRI study found that disgusting stimuli were the hardest to forget compared to fearful and sad stimuli, and increased amygdala activity along with the hippocampus95.…”

How Emotional Arousal Enhances Episodic Memory

“…When semantic relatedness is controlled, there is no evidence for increased false alarms for emotional pictures (Choi et al, 2013). Consideration of discrete emotions may also be important as hits and false alarm rates can differ across discrete emotions, such as disgust, fear, and sadness (Marchewka et al, 2016).…”

Arousal Rather than Basic Emotions Influence Long-Term Recognition Memory in Humans

“…This effect was most pronounced in the case of disgust. Recent studies have already shown that stimuli eliciting disgust are able to capture and hold our attention much more effectively than fear-evoking images (Van Hooff et al, 2013 ; van Hooff et al, 2014 ) and are better remembered after a short retention period (Croucher et al, 2011 ; Marchewka et al, 2016 ). However, it is still debated whether disgust, since it is evidently a basic sensory affect (Rozin and Fallon, 1987 ) as well as a socially constructed moral emotion (Haidt, 2003 ), should be classified as a basic emotion (for discussion see Panksepp, 2007 ; Toronchuk and Ellis, 2007 ; Panksepp and Watt, 2011 ).…”

“…At the neuronal level, using fMRI and the directed forgetting paradigm, it was revealed that correctly recognized disgusting stimuli evoked the highest activity in the left amygdala compared to all other categories. This structure was also more activated for remembered vs. forgotten stimuli, but only in case of disgust or fear eliciting pictures (Marchewka et al, 2016 ).…”