The influence of emotional associations on the neural correlates of semantic priming

Abstract

Emotions influence our everyday life in several ways. With the present study, we wanted to examine the impact of emotional information on neural correlates of semantic priming, a well-established technique to investigate semantic processing. Stimuli were presented with a short SOA of 200 ms as subjects performed a lexical decision task during fMRI measurement. Seven experimental conditions were compared: positive/negative/neutral related, positive/negative/neutral unrelated, nonwords (all words were nouns). Behavioral data revealed a valence specific semantic priming effect (i.e., unrelated > related) only for neutral and positive related word pairs. On a neural level, the comparison of emotional over neutral relations showed activation in left anterior medial frontal cortex, superior frontal gyrus, and posterior cingulate. Interactions for the different relations were located in left anterior part of the medial frontal cortex, cingulate regions, and right hippocampus ( positive > neutral + negative) and left posterior part of medial frontal cortex (negative > neutral + positive). The results showed that emotional information have an influence on semantic association processes. While positive and neutral information seem to share a semantic network, negative relations might induce compensatory mechanisms that inhibit the spread of activation between related concepts. The neural correlates highlighted a distributed neural network, primarily involving attention, memory and emotion related processing areas in medial fronto-parietal cortices. The differentiation between anterior (positive) and posterior part (negative) of the medial frontal cortex was linked to the type of affective manipulation with more cognitive demands being involved in the automatic processing of negative information

Semantic memory: Distinct neural representations for abstractness and valence

“…Activation in response to valenced words, collapsing across concreteness, in this analysis included bilateral temporal pole, STS, and angular gyrus, left IFG, and portions of the anterior and posterior cingulate cortex. These findings, particularly the medial activations, are highly consistent with other neuroimaging studies of single word reading of emotional words (Kuchinke, Jacobs, Grubich, Vo, Conrad & Herrmann, 2005; Nakic, Smith, Busis, Vythilingam, & Blair, 2006; Sass, Habel, Sachs, Huber, Gauggel & Kircher, 2012). …”

Emotional Verbal Fluency: A New Task on Emotion and Executive Function Interaction

“…This finding supports a large body of research suggesting that healthy individuals generally exhibit a positivity bias, which affects many aspects of cognition, e.g., [28,29]. For example, during studies on automatic semantic processing it was shown that subjects process positive information easily and comparable to neutral information while negative information is suppressed or even inhibited, e.g., [10]. In addition, as the task is not only based on emotional processing but also on cognitive processes, the presentation of a emotionally negative word might “interfere” with the cognitive processes leading to inferior performance (see also [10] for a discussion of emotional interference with cognitive processes).…”

Affective value and associative processing share a cortical substrate

“…In this kind of model, mOFC would be involved in overseeing the scope of associative processing such that positively valenced signals would trigger a broadening of this scope, and signals indicating negative valence in an object would result in narrowing this scope through inhibition of associative processing by mOFC (cf. Sass, et al, 2011), similarly to what is seen in the narrowing of attentional focus for negatively valenced stimuli (Baddeley, 1972; Gasper & Clore, 2002). While still largely hypothetical, this model gains support from recent findings in rhesus macaques showing that nearby perigenual ACC (BA 32) projects to regions of parahippocampal cortex in ways that would allow it to exert excitatory and inhibitory control over the local information processing circuitry (Bunce & Barbas, 2011).…”

“…Directly replicating previous studies of associativity (Aminoff, Schacter, & Bar, 2008; Bar & Aminoff, 2003), we found that neutral objects with strong associations significantly increased BOLD activity in mOFC, when compared to weakly associative objects (left: F (1,54) = 33.3; right: F (1,54) = 15.4; p ’s<0.001, corrected). Mirroring findings for a number of different kinds of affectively valenced stimuli (Brown, et al, 2011; Chib, Rangel, Shimojo, & O’Doherty, 2009; Lebreton, Jorge, Michel, Thirion, & Pessiglione, 2009; Nielen, et al, 2009; O’Doherty, Critchley, Deichmann, & Dolan, 2003a; Sass, et al, 2011), BOLD activity in mOFC also increased significantly for Positive objects compared with the neutrally valenced objects (i.e., Neutral-Strong and Neutral-Weak combined) and compared with the Negative objects (left: F (3,72) = 8.2, p <0.001, corrected; right: F (3,72) = 3.4, p <0.05, corrected; Fig. 2c).…”

“…First, this is the approach used by a number of studies whose findings we were most closely attempting to replicate, both for associativity (e.g., Bar & Aminoff, 2003) and valence (e.g. Nielen et al, 2009; Ritchey et al, 2011; Sass et al, 2011). Second, because valence and associativity turned out to be intercorrelated (see Results) the second set of analyses tested for fully independent effects of the two object dimension on mOFC activity by forming stimulus categories matched along the potentially confounding dimension.…”