Emotional arousal and affiliation

Schachter's 1959 emotional comparison theory was criticized by Sarnoff and Zimbardo 1961, who demonstrated that there are certain kinds of emotional arousal in which isolation is preferred. The generality of the theory was restricted and the direction of affiliative behaviors in different emotional-arousal conditions was questioned. In an attempt to reconcile the opposing findings, affiliative reactions to general and specific emotional arousal were compared. General arousal, anxiety state, was experimentally induced by confronting subjects with unspecified and cognitively unclear threat which allowed undetermined modes of personal interpretations. Specific arousal was induced by replicating Sarnoff and Zimbardo's experimental procedures. As predicted, general arousal increased affiliation while specific arousal decreased it. Birth order failed to interact significantly with any variables, and did not affect affiliation.Based on present and previous findings, some generalizations about emotional comparison and affiliation were offered, and problems of studying underlying motivations for affiliation were discussed.     

Emotional valence and arousal effects on memory and hemispheric asymmetries

This study examined predictions based upon the right hemisphere (RH) model, the valence–arousal model, and a recently proposed integrated model (Killgore & Yurgelun-Todd, 2007) of emotion processing by testing immediate recall and recognition memory for positive, negative, and neutral verbal stimuli among 35 right-handed women. Building upon methodologies of previous studies, we found that words presented to the right visual field/left hemisphere (RVF/LH) were recalled and recognized more accurately than words presented to the left visual field/right hemisphere (LVF/RH), and we found significant valence by visual field interactions. Some findings were consistent with one of the models evaluated whereas others were consistent with none of the models evaluated. Our findings suggest that an integration of the RH and valence–arousal models may best account for the findings with regard to hemispheric lateralization of memory for emotional stimuli.     

Emotional arousal and overeating in restrained eaters.

We tested the effects of 3 mood inductions (neutral, positive, and negative) on food intake in 91 women of varying degrees of dietary restraint. Mood induction was accomplished by exposure to 1 of 3 film segments: a travelogue (neutral affect), a comedy film (positive affect), and a horror film (negative affect). In subjects exposed to the neutral film, food intake decreased with increasing levels of dietary restraint. Among subjects who viewed either the comedy film or the horror film, however, food intake increased with increasing restraint. Although the horror film appeared to be more disinhibiting than the comedy film, this effect may have resulted from a difference in the intensity of the emotions induced rather than from their valence. These results suggest that emotional arousal, regardless of valence, may trigger overeating among restrained eaters.     

Emotional valence and arousal interact in attentional control

ABSTRACT— A recent study demonstrated that observers' ability to identify targets in a rapid visual sequence was enhanced when they simultaneously listened to happy music. In the study reported here, we examined how the emotion-attention relationship is influenced by changes in both mood valence (negative vs. positive) and arousal (low vs. high). We used a standard induction procedure to generate calm, happy, sad, and anxious moods in participants. Results for an attentional blink task showed no differences in first-target accuracy, but second-target accuracy was highest for participants with low arousal and negative affect (sad), lowest for those with strong arousal and negative affect (anxious), and intermediate for those with positive affect regardless of their arousal (calm, happy). We discuss implications of this valence-arousal interaction for the control of visual attention.     

Emotional arousal enhances word repetition priming

Three experiments were conducted to determine if emotional content increases repetition priming magnitude. In the study phase of Experiment 1, participants rated high-arousing negative (taboo) words and neutral words for concreteness. In the test phase, they made lexical decision judgements for the studied words intermixed with novel words (half taboo, half neutral) and pseudowords. In Experiment 2, low-arousing negative (LAN) words were substituted for the taboo words, and in Experiment 3 all three word types were used. Results showed significant priming in all experiments, as indicated by faster reaction times for studied words than for novel words. A priming × emotion interaction was found in Experiments 1 and 3, with greater priming for taboo relative to neutral words. The LAN words in Experiments 2 and 3 showed no difference in priming magnitude relative to the other word types. These results show selective enhancement of word repetition priming by emotional arousal.     

Emotional time distortions: the fundamental role of arousal

An emotion-based lengthening effect on the perception of durations of emotional pictures has been assumed to result from an arousal-based mechanism, involving the activation of an internal clock system. The aim of this study was to systematically examine the arousal effect on time perception when different discrete emotions were considered. The participants were asked to verbally estimate the duration of emotional pictures from the International Affective Picture System (IAPS). The pictures varied either in arousal level, i.e., high/low-arousal, for the same discrete emotion (disgust or sadness) or in the depicted emotion, e.g., disgust/fear for pictures matched for arousal (high-arousal). The results systematically revealed a lengthening effect on the perception of the duration of the emotional compared to the neutral pictures and indicated that the magnitude of this effect increased with arousal level. Nevertheless, variations in time perception were observed for one and the same arousal level, with the duration of disgust-inducing pictures (e.g., body mutilation) being judged longer than that of fear-inducing pictures (e.g., snake). These results suggest that arousal is a fundamental mechanism mediating the effect of emotion on time perception. However, the effect cannot be reduced to arousal, since the impact of the content of pictures also plays a critical role.     

Emotional time distortions: The fundamental role of arousal

An emotion-based lengthening effect on the perception of durations of emotional pictures has been assumed to result from an arousal-based mechanism, involving the activation of an internal clock system. The aim of this study was to systematically examine the arousal effect on time perception when different discrete emotions were considered. The participants were asked to verbally estimate the duration of emotional pictures from the International Affective Picture System (IAPS). The pictures varied either in arousal level, i.e., high/low-arousal, for the same discrete emotion (disgust or sadness) or in the depicted emotion, e.g., disgust/fear for pictures matched for arousal (high-arousal). The results systematically revealed a lengthening effect on the perception of the duration of the emotional compared to the neutral pictures and indicated that the magnitude of this effect increased with arousal level. Nevertheless, variations in time perception were observed for one and the same arousal level, with the duration of disgust-inducing pictures (e.g., body mutilation) being judged longer than that of fear-inducing pictures (e.g., snake). These results suggest that arousal is a fundamental mechanism mediating the effect of emotion on time perception. However, the effect cannot be reduced to arousal, since the impact of the content of pictures also plays a critical role.     

Emotional arousal and gender differences in aggression: A meta‐analysis

This meta‐analysis investigated the possibility that gender differences in aggression, and the variability in these differences, are a function of gender differences in the regulation of arousal generated in emotionally evocative contexts. The sample of studies for this analysis was based on an exhaustive search of the relevant research reports from 1965–1999. Studies were excluded from the sample if they were case studies; investigated spousal/familial or societal violence, war, suicide, or political violence; involved clinical or deviant participants; included fewer than 10 participants; included all male, all female, all non‐Caucasian, or non‐US/non‐Canadian participants. Based on previous evidence that males may be more easily aroused by aggressive‐relevant emotional stimuli than females, and that males may have more difficulty regulating emotionally arousing states than females, we hypothesized that the magnitude of the gender differences in aggression would covary, in a nonlinear manner, with the emotional evocativeness of the study context. Consistent with our hypothesis, the magnitude of gender differences in aggression was relatively small in research contexts that appeared to produce no or large increments in emotional arousal and larger (favoring males) in contexts that appeared to produce small or medium increments in emotional arousal. Aggr. Behav. 28:366–393, 2002. © 2002 Wiley‐Liss, Inc.     

Consumption experience of impulse buying in Indonesia: Emotional arousal and hedonistic considerations

Two studies focused on impulsive purchase experiences. Feelings, considerations and ratings of purchase impulsiveness were measured with respect to a recent purchase by means of interviews immediately after the purchase in the shopping environment (Study 1) and through shopping diaries (Study 2). Feelings and considerations were measured by open-ended questions, which yielded a wide range of responses in each category. These responses were subjected to multidimensional scaling. The results demonstrated a high versus low arousal dimension of positive emotions and a hedonic versus utilitarian dimension of considerations. Emotions and considerations were predicted by general impulse-buying tendency, and were related to the experience of impulsive purchases. In Study 2, impulse buying tendency was measured 2 months earlier. Structural equation modelling confirmed a model in which general impulse buying tendency predicts the feelings and considerations in the purchase environment, which in turn, determine the experience of making an impulsive purchase.     

False physiological feedback and persuasion: Effect of fear arousal vs. fear reduction on attitude change

Two experiments tested the hypothesis that increases in false physiological feedback of fear arousal will enhance persuasion and that reduction in the arousal feedback is unnecessary for increased persuasion to occur. Prior research has usually found a positive relation between level of arousal and persuasion, but support for the drive reduction hypothesis is tenuous. However, Harris and Jellison (1971) claimed support for such a hypothesis. They manipulated subjects' fear arousal cognitively via false physiological feedback while the subjects listened to a persuasive communication. The present experiments used a similar procedure in an attempt to test an "arousal only" against an "arousal reduction" hypothesis. Subjects listened to a persuasive speech while receiving false feedback via a meter concerning their fear arousal. In Experiment I half of the subjects received high arousal and half received moderate arousal information. Within each of these conditions half of the subjects had their arousal reduced, and the other half did not. In Experiment II subjects received either low arousal, high arousal, or high then low arousal feedback while listening. The results of the two studies generally provided support for the "arousal only" hypothesis. An interpretation in terms of Bem's attribution theory was tentatively suggested.     

Emotional arousal and memory: a test of the poststimulus processing hypothesis

Emotional arousal is believed to enhance memory for details central to an episode but impair memory for peripheral details. However, new research suggests that arousal induced thematically (i.e., through involvement with an unfolding event) produces only memory enhancements. This article examines whether consciously controlled elaborative processing in the aftermath of an arousing experience is responsible. A dual task manipulation was used to prevent participants from ruminating over a video that depicted an abduction and attack. Several indices of recall showed greater memory for emotional event details than for details from a neutral control video, which remained the case when the opportunity for post-stimulus elaboration was prevented. Thus, superior retention of the content of emotional experiences may arise from the way in which arousal is induced rather than through immediate postevent cognitions.     

Cognitive and affective matching effects in persuasion: an amplification perspective

Past research suggests that cognitive and affective attitudes are more open to change toward cognitive and affective (i.e., matched) persuasive attacks, respectively. The present research investigates how attitude certainty influences this openness. Although an extensive literature suggests that certainty generally reduces an attitude's openness to change, the authors explore the possibility that certainty might increase an attitude's openness to change in the context of affective or cognitive appeals. Based on the recently proposed amplification hypothesis, the authors posit that high (vs. low) attitude certainty will boost the resistance of attitudes to mismatched attacks (e.g., affective attitudes attacked by cognitive messages) but boost the openness of attitudes to matched attacks (e.g., affective attitudes attacked by affective messages). Two experiments provide support for this hypothesis. Implications for increasing the openness of attitudes to both matched and mismatched attacks are discussed.     

Emotional arousal impairs association memory: roles of prefrontal cortex regions

The brain processes underlying impairing effects of emotional arousal on associative memory were previously attributed to two dissociable routes using high-resolution fMRI of the MTL (Madan et al. 2017). Extrahippocampal MTL regions supporting associative encoding of neutral pairs suggested unitization; conversely, associative encoding of negative pairs involved compensatory hippocampal activity. Here, whole-brain fMRI revealed prefrontal contributions: dmPFC was more involved in hippocampal-dependent negative pair learning and vmPFC in extrahippocampal neutral pair learning. Successful encoding of emotional memory associations may require emotion regulation/conflict resolution (dmPFC), while neutral memory associations may be accomplished by anchoring new information to prior knowledge (vmPFC).

Emotional arousal is well known to enhance memory for individual items (Schümann and Sommer 2018), but can have impairing effects on associative memory, particularly when items cannot be easily unitized and interitem associations have to be formed (Madan et al. 2012; Murray and Kensinger 2013; Bisby and Burgess 2017). The neural substrates of the impairing effect of emotional arousal on associative memory have only begun to be explored (Bisby et al. 2016; Madan et al. 2017). Emotional arousal may disrupt hippocampal functions that are critical to promote binding and thereby lead to reduced associative memory for emotionally arousing items (“disruption hypothesis”) (Bisby et al. 2016). Conversely, encoding of neutral items may engage extrahippocampal medial temporal lobe (MTL) regions, areas we interpreted to promote better incidental unitization of neutral than negative items, leading to a net-decrease in associative memory for negative items (“bypassing hypothesis”) (Madan et al. 2017).Specifically, in our previous high-resolution fMRI study focussing on MTL regions (Madan et al. 2017), extrahippocampal MTL cortex was more active during encoding of neutral than negative picture pairs, showed a subsequent memory effect (SME) for neutral picture pairs, and neutral pair encoding was accompanied by more between-picture saccadic eye movements compared with negative pairs. In line with previous findings of extrahippocampal MTL areas involved in association memory formation of merged or unitized items (Giovanello et al. 2006; Quamme et al. 2007; Diana et al. 2008; Delhaye et al. 2019), we interpreted our fMRI and eye movement findings to suggest better incidental unitization of neutral picture pairs than negative pictures pairs. A behavioral follow-up study confirmed that unitization, that is, imagining the two pictures as one (“interactive imagery”), was indeed rated as higher for neutral than negative pairs, and this advantage in interactive imagery was linked to better associative memory for neutral pairs, lending further support to the bypassing hypothesis (Caplan et al. 2019).What would prevent emotional pairs from being as easily merged as neutral pairs? We observed that during negative pair encoding, each individual picture was fixated longer compared with neutral pictures. These longer fixation durations for negative pictures were related to greater activity during negative than neutral pair encoding in the dorsal amygdala (likely the centromedial group) (Hrybouski et al. 2016), an activation which was functionally coupled to the more ventral amygdala (likely the lateral nucleus) (Hrybouski et al. 2016). This ventral amygdala activation exhibited a subsequent forgetting effect specifically for negative pairs. Given that emotional items attract more attention to themselves and are more likely processed as individual items (Markovic et al. 2014; Mather et al. 2016), we conjectured that this may make pairs of emotional items harder to unitize and to benefit from extrahippocampal unitization-related processes such as interactive imagery. Interestingly, the hippocampus revealed a subsequent memory effect specifically for negative pairs in Madan et al. (2017). We concluded that when sufficiently arousing information precludes extrahippocampal unitization-based encoding, an alternative, compensatory, and effortful relational hippocampus-dependent encoding strategy may be used.Both findings, extrahippocampal MTL encoding for neutral pairs and compensatory hippocampal encoding for negative pairs, raise the question of which cortical areas could be involved in these two dissociable associative encoding processes. Conceivably, successful associative encoding of negative information may require participants to evaluate the emotional content, and regulate emotional arousal/conflict, functions primarily associated with dorso-medial PFC regions (dmPFC; Dixon et al. 2017), the anterior cingulate cortex (ACC) (Botvinick 2007), and posterior areas of the ventro-medial PFC (vmPFC) (Yang et al. 2020). To unitize two pictures through interactive imagery, retrieval of semantic memories and prior knowledge regarding the contents of the two pictures is likely helpful. Semantic memory processes have been attributed to the left inferior frontal gyrus (left IFG) (Binder and Desai 2011). The vmPFC (more anterior portions) could also be involved, owing to its role in relating new information during encoding to prior knowledge, that is, a “unitization-like” process (Gilboa and Marlatte 2017; Sommer 2017). Motivated by our previous discovery and interpretation of the two distinct encoding processes in the MTL (Madan et al. 2017), the potential contribution of these cortical areas in neutral and negative association memory was explored here by using a whole-brain scan and overcoming the limitations of our previous high-resolution fMRI sequence focused only on the MTL in Madan et al. (2017).In the current study, we therefore acquired standard-resolution whole-brain fMRI (3 Tesla Siemens Trio scanner, 3-mm thickness, TR 2.21 sec, TE 30 msec) of 22 male participants during exactly the same task as in Madan et al. (2017). Only male participants were recruited because of known sex-dependent lateralization of amygdala activity (Cahill et al. 2004; Mackiewicz et al. 2006), limiting the conclusions of the current study to males. Eye movements were assessed as a proxy for overt attention (EyeLink 1000, SR Research, 17 participants with usable eye-tracking data). In each of three encoding-retrieval cycles, 25 neutral and 25 negative picture pairs were intentionally encoded. Pictures (e.g., objects, scenes, humans, and animals) were selected from the International Affective Picture System (Lang et al. 2008) and the internet, and confirmed to have different valence and arousal through independent raters (details in Madan et al. 2017). Each encoding round was followed by a two-step memory test for each pair: In a judgement of memory (JoM) task one picture served as retrieval cue and volunteers indicated their memory (yes/no) for the other picture of the original pair. Then the same picture was centrally presented again, surrounded by five same-valence pictures (one correct target, four lures) in a five-alternative forced-choice associative recognition test. Participants chose the target picture from the array with an MR-compatible joystick.As in our previous studies, associative recognition was less accurate for negative (NN) (M = 0.47) than neutral (nn) pairs (M = 0.51; t(22) = 2.49, P = 0.02). Subjective memory confidence (JoM) for neutral pairs (M = 0.41) was not significantly different from confidence for negative pairs (M = 0.43; t(22) = 1.19, P = 0.25) (Fig. 1A; Madan et al. 2017; Caplan et al. 2019).Open in a separate windowFigure 1.Behavioral and eye tracking results. (A) Accuracy in the associative recognition task (5-AFC) for all negative (NN) and neutral (nn) pairs. Chance level in the 5-AFC associative recognition task was 1/5 = 0.20. (B) Mean number of saccades between the two pictures of a pair for remembered (Hit) and forgotten (Miss) negative (NN) and neutral (nn) pairs. (C) Mean number of saccades within pictures. Error bars are 95% confidence intervals around the mean, corrected for interindividual differences (Loftus and Mason 1994).Average fixation duration (a proxy for the depth of processing of individual pictures) was longer for negative than neutral pictures (F_(1,16) = 9.59, P = 0.007), with no main effect of memory (F_(1,16) = 0.11, P = 0.75), nor emotion–memory interaction (F_(1,16) = 1.27, P = 0.28). The number of fixations was also higher for negative than neutral pictures (F_(1,16) = 5.56, P = 0.03), again with no main effect of memory (F₍₁₎ = 1.56, P = 0.23) or interaction (F_(1,16) = 0.26, P = 0.61). The number of saccades within each picture (i.e., visual exploration within but not across items, reflecting intraitem processing) was higher for negative than neutral pairs (Fig. 1B; F_(1,16) = 33.38, P < 0.001), with no main effect of memory (F_(1,16) = 0.02, P = 0.89) nor interaction (F_(1,16) = 0.15, P = 0.71). However, the number of saccades between the two pictures of a pair, which may support associative processing, was substantially lower for negative than neutral pairs (Fig. 1C; F_(1,16) = 7.67, P = 0.01). Importantly, there were more between-picture saccades for pairs that were later remembered than forgotten, that is, a subsequent memory effect based on between-picture saccades (F_(1,16) = 8.43, P = 0.01). This effect did not further interact with emotion (F_(1,16) = 2.64, P = 0.12). Thus, association memory success was driven by interitem saccades, and these were reduced in negative trials. Participants spent more attention to individual negative than neutral pictures (fixation duration and number of within-picture saccades), but this was unrelated to association memory success.The fMRI data were preprocessed (slice timing corrected, realigned and unwarped, normalized using DARTEL and smoothed, FWHM = 8 mm) and analyzed using SPM12. First-level models were created with four regressors that modeled the onsets of the 2 (negative and neutral) × 2 (subsequent hits and misses) conditions of interest. Results of all fMRI analyses were considered significant at P < 0.05, family-wise error (FWE) corrected for multiple comparisons across the entire scan volume or within the a priori anatomical regions of interest (ROIs). ROIs for the hippocampus, amygdala and extrahippocampal MTL were reused from our previous study (Madan et al. 2017). The prefrontal ROIs, that is, dmPFC, ACC, vmPFC and left inferior frontal gyrus ROIs, were manually traced on the mean T1 image using ITK-SNAP 3.6.0 (Yushkevich et al. 2006) following schematic drawings based on meta-analyses (Binder and Desai 2011; Dixon et al. 2017; Gilboa and Marlatte 2017).The second-level analyses based on the resulting individual β images and subject as a random factor replicated a well-established network of brain areas involved in negative emotion processing (Spalek et al. 2015): greater activity during processing negative than neutral picture pairs in the amygdala, insula, right inferior frontal gyrus, mid, and anterior cingulate cortex as well as visual areas (Fig. 2A). As in our previous study, we correlated the difference in left amygdala activity with the difference in eye movements for negative minus neutral trials, showing a significant correlation with the number of within-picture saccades (r = 0.50, P = 0.018). Thus, higher left amygdala activity was associated with increased visual search within negative pictures. We conducted a psychophysiological interaction analysis (PPI) using this amygdala region as seed and contrasted functional coupling during successful versus unsuccessful negative with successful versus unsuccessful neutral pair encoding (i.e., the interaction of valence and subsequent memory success). This PPI revealed stronger coupling during successful encoding of negative compared with neutral pairs with a (nonsignificant) cluster in the dmPFC (Z = 3.01, [−12, 38, 26]). Simple effects showed that the amygdala was more strongly coupled with the dmPFC during successful than unsuccessful negative pair encoding (Z = 3.63, [−2, 16, 42]).Open in a separate windowFigure 2.Main effects of emotion—fMRI results. (A) Greater activity during negative than neutral pair processing irrespective of subsequent memory success. (B) Greater activity during neutral than negative pairs processing. t-maps thresholded at P < 0.001 uncorrected for visualization purposes. t-value color-coded.Neutral-pair processing was associated with greater activity than negative-pair processing in the bilateral extrahippocampal MTL cortex, ventral precuneus (vPC), retrosplenial cortex (RSC), middle occipital gyrus, and putamen (Fig. 2B). In addition, we observed a general SME irrespective of valence in the left hippocampus ([−28, −16, −24], Z = 3.49, P = 0.04).An interaction between pair valence and SME with greater neutral than negative SME was observed in vmPFC (Fig. 3A), together with a (nonsignificant) cluster in right MTL cortex ([26, −24, −28], Z = 3.16, P = 0.11). We conducted a PPI using this vmPFC region as seed and contrasted functional coupling during successful vs. unsuccessful neutral with successful vs. unsuccessful negative pair encoding. This PPI revealed stronger coupling during successful encoding of neutral compared with negative pairs in a cluster at the border of the extrahippocampal MTL cortex reaching into the hippocampus ([−20, −18, −26], Z = 4.61, Fig. 3B).Open in a separate windowFigure 3.SME × Emotion interactions and PPIs. (A) Activity in the vmPFC revealed a SME only for neutral but not negative pairs. (B) This region was stronger coupled during neutral than negative pair encoding with a cluster in the border of left MTL cortex/hippocampus. (C,D) Activity in the right hippocampus and dmPFC revealed a SME only for negative pairs. (E) The dmPFC was stronger coupled during negative than neutral pairs encoding with the bilateral hippocampus. t-maps thresholded at P < 0.001 uncorrected for visualization purposes. Error bars are 95% confidence intervals around the mean, corrected for interindividual differences (Loftus and Mason 1994).Conversely, an interaction between pair valence and SME showing a greater negative than neutral SME was observed in the right hippocampal region (Fig. 3C), replicating our previous finding of compensatory hippocampal encoding, and in the insula (Z = 3.7, [38, 2, 8]). Within prefrontal cortex, the dorsal medial prefrontal cortex (dmPFC, Z = 4.14) (Fig. 3D), also showed this effect. Neutral pairs showed a subsequent forgetting effect, that is, greater activity during unsuccessful encoding of neutral pairs, in these regions (Fig. 3 C,D).Similar to the PPI with the vmPFC seed, we conducted a PPI with the dmPFC cluster as seed. This PPI revealed the bilateral hippocampus to be more strongly coupled with the dmPFC during successful negative than neutral pair encoding (Z = 3.98, [−24, −10, −18], Z = 4.71, [30, −14, −29]) (Fig. 3E). The correlational analyses of activity in the dmPFC and vmPFC (valence × encoding success interactions) with the corresponding eye-tracking measures were nonsignificant, possibly due to low reliability of difference measures (Schümann et al. 2020).The current findings, first, replicated the impairing effects of emotional arousal on association memory previously observed in six experiments across four studies (Madan et al. 2012, 2017; Caplan et al. 2019). We built on these previous findings here by identifying cortical, especially prefrontal areas involved in the associative memory advantage for neutral pairs and those involved in the compensatory mechanism for learning negative pairs. In particular, vmPFC activity more strongly supported successful encoding of neutral than negative pairs and during this process, showed stronger coupling with a cluster at the border between MTL cortex and hippocampus. Conversely, the dmPFC was more engaged and more strongly coupled with the hippocampus during successful negative than neutral pair encoding.We observed more and longer fixations, as well as more within-picture saccades for individual negative pictures compared with neutral pictures, resembling previously reported eye movement findings (Bradley et al. 2011; Dietz et al. 2011). We had previously shown that increased attention (fixation duration) to individual negative pictures is linked to centromedial amygdala activity (not measurable here due to the whole-brain scan resolution), and functionally coupled with a negative pair-specific subsequent forgetting effect in the lateral amygdala (Madan et al. 2017). These findings together suggest that increased attention attracted by individual negative pictures does not support associative memory, or may even be detrimental (cf., Hockley and Cristi 1996).The dmPFC contributed more to negative than neutral association memory and was functionally coupled to the hippocampus, which complements our interpretation of possibly compensatory activity in the hippocampus during negative pair encoding (Madan et al. 2017). The amygdala on the other hand was stronger coupled with the dmPFC during successful encoding of negative pairs which might reflect the detection of aversive stimuli by the amygdala. The dmPFC not only plays a role in emotion regulation (Wager et al. 2008; Ochsner et al. 2012; Kohn et al. 2014; Dixon et al. 2017): It is the central node in the cognitive control network. In particular, the dmPFC regulates conflicts between goals and distracting stimuli by boosting attention toward the relevant task (Weissman 2004; Grinband et al. 2011; Ebitz and Platt 2015; Iannaccone et al. 2015). Consistent with this role in the current task, the dmPFC was functionally more strongly coupled with the bilateral hippocampus during successful negative compared with neutral pair learning. The involvement of the dmPFC during successful negative (but unsuccessful neutral) (discussed below) pair encoding may suggest that it resolves conflicts between the prepotent attention to the individual negative pictures and the current task goals, that is, their intentional associative encoding. One way to do so might involve the dmPFC''s role to regulate the negative emotions elicited by the pictures in order to focus on the associative memory task.Neutral pairs elicited more between-picture saccades than negative pairs, as in (Madan et al. 2017). The vmPFC was more strongly involved in successful associative encoding of neutral than negative pairs and more strongly coupled with the extrahippocampal MTL cortex bordering the hippocampus during successful neutral compared with negative pair encoding. Anterior vmPFC regions and their coupling with the MTL have been implicated in retrieval of consolidated memories and in anchoring new information to prior knowledge (Nieuwenhuis and Takashima 2011; van Kesteren et al. 2013; Schlichting and Preston 2015; Gilboa and Marlatte 2017; Sommer 2017; Brod and Shing 2018; Sekeres et al. 2018). We previously observed that interactive imagery (forming one instead of two images to memorize) was higher for neutral than negative pairs (Caplan et al. 2019), perhaps reflected by the increased between-picture saccades in the current study. Assuming that the anterior vmPFC subserves retrieval of prior knowledge, its engagement during successful neutral pair encoding may have supported such incidental unitization processes here as well. Negative pictures are inherently semantically more related (Barnacle et al. 2016), which implies that they may share even more prior knowledge than neutral pictures. However, the retrieval of this prior knowledge may be inhibited by the attraction of attention to individual negative pictures, not their arbitrary pairing as in the current task. Incidental unitization can occur through rather subtle manipulations (Giovanello et al. 2006; Diana et al. 2008; Bader et al. 2010; Ford et al. 2010; Li et al. 2019) or even entirely without any instruction; for example, when the items’ combination is itself meaningful or familiar (Ahmad and Hockley 2014). We suggest that similar incidental unitization processes may have occurred here as well. Memory for unitized associations is independent of hippocampal memory processes and can be based solely on the extrahippocampal MTL (Quamme et al. 2007; Haskins et al. 2008; Staresina and Davachi 2010). Our previous high-resolution fMRI study supported such a bypassing hypothesis, that is, extrahippocampal MTL cortex involvement in the successful associative encoding of neutral but not negative pairs (Madan et al. 2017). Here, this interaction did not reach significance in the MTL cortex, but the P-value of 0.11 can be considered suggestive based on our strong a priori-hypothesis. Notably, in our previous study using a scanning resolution of 1 mm³ the cluster included only 17 voxels, which would correspond to less than one voxel here. Therefore, we assume the lower sensitivity here was due to the lower spatial resolution.Unexpectedly, we observed greater activity during unsuccessful encoding of neutral pairs in the same regions that promoted successful encoding of negative pairs, that is, the dmPFC and hippocampal region. Hockley et al. (2016) previously observed that incidental but not intentional encoding of associations (for word pairs) improved for items with stronger pre-experimental associations. Perhaps using an effortful (dmPFC/hippocampal) learning strategy for neutral pairs, that is, pairs that are already more likely incidentally linked or linkable (e.g., through interactive imagery) may not have helped encoding. The forgotten neutral pairs underlying the SFE in these regions may then have been simply the hardest-to-learn neutral pairs; that is, pairs where both encoding strategies failed. Evidently, future studies should test such speculations directly.Our interpretation of the dmPFC and vmPFC as signifying in emotion regulation and unitization in this task was based on previous studies. Because we did not manipulate unitization and/or emotional regulation, these processes remain hypothetical. However, within this framework, we addressed two hypotheses regarding interactions between hippocampal/extrahippocampal MTL regions and prefrontal cortex during association memory formation. The disruption hypothesis proposes that the hippocampus is equally responsible for encoding of negative and neutral association memory but that for negative memories, hippocampal activity is inhibited by the amygdala via the prefrontal cortex (Murray and Kensinger 2013; Bisby et al. 2016). The vmPFC has known involvement in negative emotion processing (Yang et al. 2020), and the observed activity pattern in the vmPFC could appear to disrupt hippocampal association memory processes for negative pairs. However, according to the bypassing hypothesis (Madan et al. 2017), successful encoding of negative (compared with neutral) pairs requires the hippocampus since fewer extrahippocampal contributions are available. Supporting the bypassing hypothesis, we observed that the vmPFC was negatively functionally coupled with extrahippocampal MTL cortex (bordering the hippocampus), suggesting that the vmPFC decreased extrahippocampal contributions to association memory for negative pairs. The bypassing hypothesis is also supported by our finding that the hippocampus was not less but more involved in negative compared with neutral pair encoding, that is, we observed no evidence for a prefrontally (e.g., vmPFC)-mediated disruption of hippocampal activity by emotion.In conclusion, the two critical prefrontal cortex regions linked to MTL memory processes in the current study were the dmPFC, involved in successful hippocampal-dependent negative pair learning and the vmPFC, supporting successful neutral pair learning that relied on extrahippocampal MTL involvement.     

The effects of name similarity on message processing and persuasion

Prior studies have found that name similarity can serve as a cue that favorably affects evaluations without conscious deliberation. In a series of four experiments, we show that name similarity can increase the conscious processing of information with which it is associated. When exposed to student resumes or advertised brands with names similar (versus dissimilar) to theirs, respondents were more likely to relate the information to themselves (self-reference, Experiments 2-4) and thoughtfully examine it. Evidence of thoughtful processing included slower reaction times when reviewing resumes and greater information recall (Experiment 1), spending more time in resume review (Experiment 2), greater evaluative differentiation between resumes and product brands of different quality (Experiments 2 and 3), and developing stronger brand attitudes (Experiment 4). An expanded view of how and why name similarity can affect persuasion is offered and discussed.     

Intentional vs arousal effects of goal-setting

The effects of goal-setting on performance can be interpreted as operating through intentions or, as a rival hypothesis, due to increased arousal. The distinction is important, since (1) intentional effects on performance would bear a functional relationship to level of task difficulty or complexity different from that of arousal effects and (2) arousal effects on performance would depend on level of individual trait anxiety. This paper reports results of two laboratory experiments attempting to isolate and compare the magnitude of intentional vs arousal effects of goal-settings. One study used a proofreading task in an “incidental learning” paradigm and the other used an anagram task with three levels of difficulty of items; both studies compared dependent behaviors of high- and low-anxiety individuals. Results from both studies offer relatively strong support for the intentions hypothesis and little evidence in favor of an arousal interpretation.