Brief learning induces a memory bias for arousing-negative words: an fMRI study in high and low trait anxious persons

Abstract

Persons suffering from anxiety disorders display facilitated processing of arousing and negative stimuli, such as negative words. This memory bias is reflected in better recall and increased amygdala activity in response to such stimuli. However, individual learning histories were not considered in most studies, a concern that we meet here. Thirty-four female persons (half with high-, half with low trait anxiety) participated in a criterion-based associative word-learning paradigm, in which neutral pseudowords were paired with aversive or neutral pictures, which should lead to a valence change for the negatively paired pseudowords. After learning, pseudowords were tested with fMRI to investigate differential brain activation of the amygdala evoked by the newly acquired valence. Explicit and implicit memory was assessed directly after training and in three follow-ups at 4-day intervals. The behavioral results demonstrate that associative word-learning leads to an explicit (but no implicit) memory bias for negatively linked pseudowords, relative to neutral ones, which confirms earlier studies. Bilateral amygdala activation underlines the behavioral effect: Higher trait anxiety is correlated with stronger amygdala activation for negatively linked pseudowords than for neutrally linked ones. Most interestingly, this effect is also present for negatively paired pseudowords that participants could not remember well. Moreover, neutrally paired pseudowords evoked higher amygdala reactivity than completely novel ones in highly anxious persons, which can be taken as evidence for generalization. These findings demonstrate that few word-learning trials generate a memory bias for emotional stimuli, indexed both behaviorally and neurophysiologically. Importantly, the typical memory bias for emotional stimuli and the generalization to neutral ones is larger in high anxious persons.

Emotion processing and the broader autism phenotype

“…Further, academic and occupational success is more strongly linked with social-emotional characteristics of individuals than with their general intelligence (Immordino-Yang, 2016). While some studies show that the perception of external emotions expressed by others can also impact learning (Berman et al, 2013;Eden et al, 2015;Herold et al, 2011;Hooker et al, 2008), our evidence suggests that relevance is key, whether that relevance be personal or relate directly to task goals.…”

“…The authors concluded that more context is needed to form stronger representations of emotion words (Altarriba & Basnight-Brown, 2011). In contrast, a study by Eden et al (2015) showed that nonsense words which participants had associated with negative images were better learned compared to words associated with neutral images. However, pairing words with images could be considered a richer context compared to word-word pairs.…”

“…Studies have shown that new words which are associated with an emotional meaning are learned differently to words with neutral meaning (Altarriba & Basnight-Brown, 2011;Eden et al, 2015). For instance, Altarriba and Basnight-Brown (2011) presented participants with words in a non-native language along with their native language translations.…”

“…Overall, emotional information resulted in interference to word learning processes. Much of the previously discussed research showing that emotional information facilitates learning and memory (Berman et al, 2013;Eden et al, 2015;Hooker et al, 2008) have utilised tasks which require explicit association of the novel stimuli with emotion. Thus an attentional bias toward emotional information in these tasks was beneficial for linking the novel stimuli with that information.…”

“…In word learning scenarios in which emotional cues are referential, word learning ability is aided by the emotional cues (Berman et al, 2013;Eden et al, 2015;Herold et al, 2011;Hooker et al, 2008). In contrast, when emotional cues are not referential, word learning ability can be negatively impacted, or not impacted at all, depending on age (Chapters 4 & 5).…”