Friday, January 27, 2006

ARTICLE UPDATE - Selective attention for negative information and depression in schizophrenia.

Waters FA, Badcock JC, Maybery MT.

Psychological Medicine

Objectives. Depression is a frequent feature of schizophrenia but the cognitive processes involved in its development and maintenance are unclear. Recent studies have shown that clinical depression is associated with faulty inhibitory mechanisms of selective attention for negative information. The current study examined whether patients with schizophrenia also have an attentional bias towards negative stimuli. The inhibitory processes of interference control and task-shifting abilities were also examined to assess whether patients would show a selective impairment.Method. Forty-three patients with schizophrenia and 24 healthy controls completed the Affective Shifting Task.Results. As a group, schizophrenia patients did not show an attentional bias for negative material. However, those patients with high levels of depression demonstrated faster latencies when negative words were the targets, and higher depression scores were found to be associated with an increasing number of false alarms for negative words when they were not the targets. The results also showed that patients had impaired interference control but intact task-shifting abilities.Conclusions. Faulty inhibitory mechanisms of selective attention for negative information are not a general feature of schizophrenia but appear to be selective to those with a depressed mood. The results highlight the need for further studies examining the exact nature of the affective dysfunction in schizophrenia and the cognitive processes supporting negative emotions.

ARTICLE UPDATE - Emotion enhances remembrance of neutral events past.

Anderson AK, Wais PE, Gabrieli JD.

PNAS, in press

Emotional events are bestowed with special prominence in memory. This may reflect greater attention oriented to these events during encoding, and/or enhancement of memory consolidation after emotional events have passed. Here we show invoked emotional arousal results in a retrograde enhancement of long-term memory, determining what will later be remembered or forgotten. Subjects saw pictures of neutral faces and houses followed by emotionally arousing scenes at varying intervals. Self-reported emotional arousal responses predicted a retrograde enhancement of memory for preceding neutral events in a 1-week delayed recognition memory test. At longer picture-scene intervals, no enhancement was found, implicating a critical window in which emotional arousal must occur for retrograde memory enhancement. Postencoding manipulation of emotional arousal specifically enhanced conscious recollection rather than familiarity-based discrimination. An additional study revealed no retrograde enhancement for pictures preceding highly memorable, but nonarousing, distinctive scenes. These findings indicate an important role for emotional arousal in the postencoding enhancement of episodic memory consolidation.

Monday, January 23, 2006

ARTICLE UPDATE - The influence of autonomic arousal and semantic relatedness on memory for emotional words

Tony W. Buchanan, Joset A. Etzel, Ralph Adolphs and Daniel Tranel

International Journal of Psychophysiology, in press

Increased memory for emotional stimuli is a well-documented phenomenon. Emotional arousal during the encoding of a stimulus is one mediator of this memory enhancement. Other variables such as semantic relatedness also play a role in the enhanced memory for emotional stimuli, especially for verbal stimuli. Research has not addressed the contributions of emotional arousal, indexed by self-report and autonomic measures, and semantic relatedness on memory performance. Twenty young adults (10 women) were presented neutral-unrelated words, school-related words, moderately arousing emotional words, and highly arousing taboo words while heart rate and skin conductance were measured. Memory was tested with free recall and recognition tests. Results showed that taboo words, which were both semantically related and high arousal were remembered best. School-related words, which were high on semantic relatedness but low on arousal, were remembered better than the moderately arousing emotional words and semantically unrelated neutral words. Psychophysiological responses showed that within the moderately arousing emotional and neutral word groups, those words eliciting greater autonomic activity were better remembered than words that did not elicit such activity. These results demonstrate additive effects of semantic relatedness and emotional arousal on memory. Relatedness confers an advantage to memory (as in the school-words), but the combination of relatedness and arousal (as in the taboo words) results in the best memory performance.

Thursday, January 19, 2006

ARTICLE UPDATE - Neural correlates of social and nonsocial emotions: An fMRI study.

Britton JC, Phan KL, Taylor SF, Welsh RC, Berridge KC, Liberzon I.

NeuroImage, in press

Common theories of emotion emphasize valence and arousal dimensions or alternatively, specific emotions, and the search for the underlying neurocircuitry is underway. However, it is likely that other important dimensions for emotional neurocircuitry exist, and one of them is sociality. A social dimension may code whether emotions are addressing an individual's biological/visceral need versus more remote social goals involving semantic meaning or intentionality. Thus, for practical purposes, social emotions may be distinguished from nonsocial emotions based in part on the presence of human forms. In the current fMRI study, we aimed to compare regional coding of the sociality dimension of emotion (nonsocial versus social) versus the valence dimension of emotion (positive versus negative). Using a novel fMRI paradigm, film and picture stimuli were combined to induce and maintain four emotions varying along social and valence dimensions. Nonsocial emotions of positively valenced appetite and negatively valenced disgust and social emotions of positively valenced joy/amusement and negatively valenced sadness were studied. All conditions activated the thalamus. Appetite and disgust activated posterior insula and visual cortex, whereas joy/amusement and sadness activated extended amygdala, superior temporal gyrus, hippocampus, and posterior cingulate. Activations within the anterior cingulate, nucleus accumbens, orbitofrontal cortex, and amygdala were modulated by both social and valence dimensions. Overall, these findings highlight that sociality has a key role in processing emotional valence, which may have implications for patient populations with social and emotional deficits.

ARTICLE UPDATE - Forgetting “murder” is not harder than forgetting “circle”: Listwise‐directed forgetting of emotional words

Ineke Wessel and Harald Merckelbach

Cognition & Emotion, 20, 129-137

The list-method directed forgetting (DF) paradigm has attracted the attention of clinical psychologists because it is widely believed that a retrieval inhibition mechanism underlies its effects. Thus, the idea is that people are capable of intentionally forgetting negative emotional material. On the other hand, there are reasons to believe that negative stimuli are relatively resistant to forgetting. The present experiment compared listwise DF of emotional and neutral words in healthy college students. A modified procedure (i.e., a simulated computer crash) showed a reliable DF-effect in that list 1 recall was larger under remember than forget instructions whereas the reverse was true for list 2 recall. Emotionality did not modulate the magnitude of this effect. Thus, negative emotional material is not resistant to forgetting. Although overall, the present findings are in line with a retrieval inhibition interpretation (i.e., decreased access to list 1 material), attentional focusing during list 2 learning may provide a sufficient explanation.

ARTICLE UPDATE - What determines a feeling's position in affective space? A case for appraisal

Klaus R. Scherer , Elise S. Dan , Anders Flykt

Cognition & Emotion, 20, 92-113

The location of verbally reported feelings in a three-dimensional affective space is determined by the results of appraisal processes that elicit the respective states. One group of participants rated their evaluation of 59 pictures from the International Affective Picture System (IAPS) on a profile of nine appraisal criteria. Another group rated their affective reactions to the same pictures on the classic dimensions of affective meaning (valence, arousal, potency). The ratings on the affect dimensions correlate differentially with specific appraisal ratings. These results can be interpreted as showing that the reactions to the IAPS pictures are predictably produced through appraisal of picture content. The relevance of the findings for emotion induction paradigms and for emotion theory in general is discussed.

Wednesday, January 11, 2006

ARTICLE UPDATE - Priming effects for affective vs. neutral faces.

Burton LA, Rabin L, Wyatt G, Frohlich J, Vardy SB, Dimitri D.

Brain and Cognition, 59, 322-329.

Affective and Neutral Tasks (faces with negative or neutral content, with different lighting and orientation) requiring reaction time judgments of poser identity were administered to 32 participants. Speed and accuracy were better for the Affective than Neutral Task, consistent with literature suggesting facilitation of performance by affective content. Priming effects were significant for the Affective but not Neutral Task. An Explicit Post-Test indicated no conscious knowledge of the stimulus frequency that was associated with performance facilitation. Faster performance by female vs. male participants, and differential speeds and susceptibility to priming of different emotions were also found. Anger and shock were responded to most rapidly and accurately in several conditions, showed no gender differences, and showed significant priming for both RT and accuracy. Fear and pain were responded to least accurately, were associated with faster female than male reaction time, and the accuracy data showed a kind of reverse priming.

ARTICLE UPDATE - Affective judgment and beneficial decision making: Ventromedial prefrontal activity correlates with performance in the Iowa Gambling

Georg Northoff, Simone Grimm, Heinz Boeker, Conny Schmidt, Felix Bermpohl, Alexander Heinzel, Daniel Hell, Peter Boesiger

Human Brain Mapping, in press

Damasio proposes in his somatic marker theory that not only cognitive but also affective components are critical for decision making. Since affective judgment requires an interplay between affective and cognitive components, it might be considered a key process in decision making that has been linked to neural activity in ventromedial prefrontal cortex (VMPFC). Using functional magnetic resonance imaging (fMRI), we examined the relationship between VMPFC, emotionally (unexpected)- and cognitively (expected)-accentuated affective judgment, and beneficial decision making (Iowa Gambling Task; IGT) in healthy subjects. Neuronal activity in the VMPFC during unexpected affective judgment significantly correlated with both global and final performance in the IGT task. These findings suggest that the degree to which subjects recruit the VMPFC during affective judgment is related to beneficial performance in decision making in gambling.

ARTICLE UPDATE - Attentional modulation of emotional stimulus processing: An fMRI study using emotional expectancy.

Bermpohl F, Pascual-Leone A, Amedi A, Merabet LB, Fregni F, Gaab N, Alsop D, Schlaug G, Northoff G.

Human Brain Mapping, in press

We used emotional expectancy to study attentional modulation in the processing of emotional stimuli. During functional magnetic resonance imaging (fMRI), volunteers saw emotional and neutral expectancy cues signaling the subsequent presentation of corresponding emotional or neutral pictorial stimuli. As a control, emotional and neutral pictures were presented without preceding expectancy cue, resulting in a 2 x 2 factorial design with the factors "expectancy" and "emotion." Statistical analysis revealed a significant positive interaction effect between these factors in the medial prefrontal cortex (MPFC, Brodmann area [BA] 9/10), amygdala, and dorsal midbrain. In all these regions, expectancy augmented the neural response to emotional but not to neutral pictures. Time course analysis of raw data suggests that this augmented activation was not preceded by baseline increases in MPFC and amygdala during the period of emotional expectancy. In a post-scanning session, the paradigm was presented for a second time to allow emotional intensity rating. Again, a significant interaction between expectancy and emotion was observed, with intensity ratings specifically enhanced in emotional photographs preceded by expectancy. There was a positive correlation between intensity ratings and blood oxygenation level-dependent (BOLD) signals in the left amygdala. We conclude that specific components of the emotion network show enhanced activation in response to emotional stimuli when these are preceded by expectancy. This enhancement effect is not present in neutral pictures and might parallel accentuated subjective feeling states. Hum. Brain Mapp 2005. (c) 2005 Wiley-Liss, Inc.

ARTICLE UPDATE - Beyond the right hemisphere: brain mechanisms mediating vocal emotional processing.

Schirmer A, Kotz SA.

Trends in Cognitive Sciences, 10, 24-30

Vocal perception is particularly important for understanding a speaker's emotional state and intentions because, unlike facial perception, it is relatively independent of speaker distance and viewing conditions. The idea, derived from brain lesion studies, that vocal emotional comprehension is a special domain of the right hemisphere has failed to receive consistent support from neuroimaging. This conflict can be reconciled if vocal emotional comprehension is viewed as a multi-step process with individual neural representations. This view reveals a processing chain that proceeds from the ventral auditory pathway to brain structures implicated in cognition and emotion. Thus, vocal emotional comprehension appears to be mediated by bilateral mechanisms anchored within sensory, cognitive and emotional processing systems.

ARTICLE UPDATE - Reduced specificity of autobiographical memories following a negative mood induction

Au Yeung C, Dalgleish T, Golden AM, Schartau P.

Behavioural Research Therapy, in press

Reduced autobiographical memory specificity (AMS) to emotional and neutral cue words appears to be a stable cognitive marker of clinical depression. For example, reduced AMS is present in remitted/recovered depressed patients and shows no reliable relationship with current levels of depressed mood in correlational studies. The present study examined whether reduced AMS could be induced in healthy volunteers with no history of depression, using a negative mood manipulation and whether levels of AMS and induced mood were positively correlated. Results showed a reduction in AMS following negative mood induction, compared to a neutral induction, whereas positive mood induction had no effects on AMS. Furthermore, lower happiness following the induction phase correlated positively with reduced AMS, and the extent of happiness reduction from pre- to post-induction correlated positively with reduction in AMS. These results suggest that AMS is, at least in part, a function of current emotion state. The implications for the literature on AMS as a stable marker of clinical depression are discussed.

ARTICLE UPDATE - Beyond threat: Amygdala reactivity across multiple expressions of facial affect.

Fitzgerald DA, Angstadt M, Jelsone LM, Nathan PJ, Phan KL.

NeuroImage, in press

The amygdala has been consistently isolated as a key neural substrate for processing facial displays of affect. Recent evidence from human lesion and functional neuroimaging studies have begun to challenge the notion that the amygdala is reserved for signals of threat (fear/anger). We performed a 4 T fMRI study in which 20 subjects viewed a contemporary set of photographs displaying 6 different facial expressions (fearful, disgusted, angry, sad, neutral, happy) while performing a task with minimal cognitive demand. Across subjects, the left amygdala was activated by each face condition separately, and its response was not selective for any particular emotion category. These results challenge the notion that the amygdala has a specialized role in processing certain emotions and suggest that the amygdala may have a more general-purpose function in processing salient information from faces.

ARTICLE UPDATE - Cognitive neuroscience of emotional memory

Labar KS, Cabeza R.

Nature Review Neuroscience, 7, 54-64

Emotional events often attain a privileged status in memory. Cognitive neuroscientists have begun to elucidate the psychological and neural mechanisms underlying emotional retention advantages in the human brain. The amygdala is a brain structure that directly mediates aspects of emotional learning and facilitates memory operations in other regions, including the hippocampus and prefrontal cortex. Emotion-memory interactions occur at various stages of information processing, from the initial encoding and consolidation of memory traces to their long-term retrieval. Recent advances are revealing new insights into the reactivation of latent emotional associations and the recollection of personal episodes from the remote past.

ARTICLE UPDATE - Emotion-induced retrograde amnesia and trait anxiety.

Miu AC, Heilman RM, Opre A, Miclea M.

Journal of Experimental Psychology: Learning, Memory and Cognition, 31, 1250-1257.

Emotional arousal can both enhance and impair memory. Considering that both emotional memory and trait anxiety (TA) have been associated with adrenergic activity, the authors investigated whether there is an association between 2 opposite emotional memory biases and the TA. The authors used a procedure recently put forward by B. A. Strange, R. Hurlemann, and R. J. Dolan (2003) to elicit an emotion-induced retrograde amnesia (ERA) coupled to an emotional memory enhancement (EME). The authors contrasted the association between these emotional memory biases and the TA in several conditions involving different levels of encoding and types of recall. The results presented here indicated a significant interaction of the TA with EME and ERA and the dependency of these biases on the consciously controlled use of memory.

Tuesday, January 10, 2006

ARTICLE UPDATE - Event-Related Potentials in a Decision-Making Task with Delayed and Immediate Reward Conditions

Marcus Heldmann, Jascha Rüsseler and Thomas F. Münte

Journal of Psychophysiology, 19, 270-274

We investigated performance monitoring of a group of healthy normal subjects in a delay of gratification paradigm. Focusing on response-locked event-related brain potentials we observed an Ne-Pe-like complex in all conditions. While there was no modulation of the Ne-like component, the subsequent Pe-like positivity was largest in conditions in which subjects went for the largest immediate reward, regardless of whether this was disadvantageous (i.e., foreclosed a larger delayed reward) or not. We interpreted the positivity as mainly reflecting the size of the immediate reward.

Monday, January 09, 2006

ARTICLE UPDATE - Levels of appraisal: A medial prefrontal role in high-level appraisal of emotional material

Raffael Kalisch, Katja Wiech, Hugo D. Critchley and Raymond J. Dolan

NeuroImage, in press

Appraisal refers to the evaluation of the meaning of emotional stimuli and is considered causal in the generation of an emotional response. Cognitive neuroscience has paid little attention to a theoretical distinction between low-level appraisal, considered to be automatic and preattentive, and high-level appraisal that requires attentional and working memory resources. To disentangle low-level from high-level appraisal, we varied cognitive load in a concurrent, unrelated working memory task, while anxiety was induced through anticipation of impending pain. Confirming theoretical predictions, we show that anxiety-related activity in dorsal medial prefrontal/rostral anterior cingulate cortex (dorsal MPFC/ACC) is attenuated under high, relative to low, cognitive load. Lateral prefrontal regions previously implicated in reappraisal and cognitive emotion regulation show a similar interaction between anxiety and cognitive load. Critically, there were no changes in physiological and subjective measures of low-level appraisal outcome and emotional response generation as a function of load, allowing us to conclude that MPFC/ACC and lateral PFC activity during anticipatory anxiety reflects high-level appraisal. Our data provide neurobiological evidence for a distinction between low-level and high-level appraisal mechanisms.

Monday, January 02, 2006

ARTICLE UPDATE - Memories for emotional autobiographical events following unilateral damage to medial temporal lobe

Tony W. Buchanan, Daniel Tranel and Ralph Adolphs

Brain, 129, 115-127

Abnormalities of both memory and emotion have been reported in patients with unilateral damage to the anteromedial temporal lobe, probably reflecting the functions of the amygdala and hippocampus in these processes. Emotion and memory are also known to interact: emotional experiences often leave remarkably durable autobiographical memories. To explore this interaction, and to extend prior studies to the domain of autobiographical memory, we investigated the recollection of real-life emotional events in patients with unilateral damage to the anteromedial temporal lobe. Twenty-three patients who had undergone unilateral temporal lobectomy for the treatment of epilepsy (12 left, 11 right) and 20 healthy comparison participants completed an emotional autobiographical memory test. Participants were asked to recollect their five most emotional memories from any time in their lives and then they completed a word-cued autobiographical memory task. Participants dated each memory and gave ratings on scales of pleasantness, intensity, significance, novelty, vividness and frequency of rehearsal. Left temporal lobectomy (LTL) and healthy comparison groups generated similar numbers of pleasant and unpleasant memories, whereas the right temporal lobectomy (RTL) group produced significantly fewer memories of unpleasant events (P < 0.01). When memories were further categorized according to pleasantness and intensity, the RTL group produced significantly fewer unpleasant/high intensity memories than the other groups (P < 0.01). All groups reported more memories from between the ages of 10 and 30 (the so-called autobiographical memory ‘bump’). The results demonstrate a positive bias in the recollection of autobiographical memory following right-sided anteromedial temporal damage. This finding is consistent with the notion that the right, but not the left, anteromedial temporal lobe is involved in the retrieval of negatively valenced, high-intensity memories.

ARTICLE UPDATE - Emotional Devaluation of Distracting Patterns and Faces: A Consequence of Attentional Inhibition During Visual Search?

Raymond, Jane E.; Fenske, Mark J.; Westoby, Nikki

Journal of Experimental Psychology: Human Perception and Performance, 31, 1404-1415

Visual search has been studied extensively, yet little is known about how its constituent processes affect subsequent emotional evaluation of searched-for and searched-through items. In 3 experiments, the authors asked observers to locate a colored pattern or tinted face in an array of other patterns or faces. Shortly thereafter, either the target or a distractor was rated on an emotional scale (patterns, cheerfulness; faces, trustworthiness). In general, distractors were rated more negatively than targets. Moreover, distractors presented near the target during search were rated significantly more negatively than those presented far from the target. Target-distractor proximity affected distractor ratings following both simple-feature and difficult-conjunction search, even when items appeared at different locations during evaluation than during search and when faces previously tinted during search were presented in grayscale at evaluation. An attentional inhibition account is offered to explain these effects of attention on emotional evaluation.

ARTICLE UPDATE - Influence of Emotion on Memory for Temporal Information

D'Argembeau, Arnaud; Van der Linden, Martial

Emotion, 5, 503-507

Contextual information, such as color and spatial location, has been found to be better remembered for emotional than for neutral items. The current study examined whether the influence of emotion extends to memory for another fundamental feature of episodic memory: temporal information. Results from a list-discrimination paradigm showed that (a) item memory was enhanced for both negative and positive pictures compared with neutral ones and was better for negative than for positive pictures and (b) temporal information was better remembered for negative than for positive and neutral pictures, whereas positive and neutral pictures did not differ from each other. These findings are discussed in relation to the processes involved in memory for temporal information.

ARTICLE UPDATE - Mental Imagery and Emotion: A Special Relationship?

Holmes, Emily A.; Mathews, Andrew

Emotion, 5, 489-497

A special association between imagery and emotion is often assumed, despite little supporting evidence. In Experiment 1, participants imagined unpleasant events or listened to the same descriptions while thinking about their verbal meaning. Those in the imagery condition reported more anxiety and rated new descriptions as more emotional than did those in the verbal condition. In Experiment 2, 4 groups listened to either benign or unpleasant descriptions, again with imagery or verbal processing instructions. Anxiety again increased more after unpleasant (but not benign) imagery; however, emotionality ratings did not differ after a 10-min filler task. Results support the hypothesis of a special link between imagery and anxiety but leave open the question of whether this also applies to other emotions.

ARTICLE UPDATE - Abstract Stimuli Associated With Threat Through Conditioning Cannot Be Detected Preattentively

Batty, Martin J.; Cave, Kyle R.; Pauli, Paul

Emotion, 5, 418-430

Studies of anxiety suggest that threat stimuli can be identified preattentively, but this conclusion is questionable because of possible low-level perceptual confounds. Two experiments used visual search tasks in which abstract shapes were conditioned to carry neutral or negative valence. Experiment 1 found generally faster responses to threat-associated abstract stimuli but no evidence that they were detected preattentively, irrespective of trait anxiety level. A similar pattern was found in Experiment 2, in which individuals high in snake or spider fear showed no evidence of preattentive detection of abstract stimuli associated with their feared object. In contrast, implicit behavioral measures showed significant effects of conditioning, demonstrating that targets associated with threat were negatively evaluated in these experiments.

ARTICLE UPDATE - Emotional Stimuli, Divided Attention, and Memory

Kern, Rosalie P.; Libkuman, Terry M.; Otani, Hajime; Holmes, Katherine

Emotion, 5, 408-417

The emotion–memory literature has shown that negative emotional arousal enhances memory. S. A. Christianson (1992) proposed that preattentive processing could account for this emotion–memory relationship. Two experiments were conducted to test Christianson’s theory. In Experiment 1, participants were exposed to neutral and negative arousing slides. In Experiment 2, participants were exposed to neutral, negative arousing, and positive arousing slides. In both experiments, the for ementioned variable was factorially combined with a divided-attention or non-divided-attention condition. The authors predicted that, in contrast to the nondivided condition, dividing attention would adversely impact neutral and positive stimuli more than negative stimuli. The hypothesis was supported; participants recalled more high negative-arousal slides than positive or neutral slides when their attention was divided rather than nondivided.

ARTICLE UPDATE - Looking for Foes and Friends: Perceptual and Emotional Factors When Finding a Face in the Crowd

Juth, Pernilla; Lundqvist, Daniel; Karlsson, Andreas; Öhman, Arne

Emotion, 5, 379-395

In a face-in-the-crowd setting, the authors examined visual search for photographically reproduced happy, angry, and fearful target faces among neutral distractor faces in 3 separate experiments. Contrary to the hypothesis, happy targets were consistently detected more quickly and accurately than angry and fearful targets, as were directed compared with averted targets. There was no consistent effect of social anxiety. A facial emotion recognition experiment suggested that the happy search advantage could be due to the ease of processing happy faces. In the final experiment with perceptually controlled schematic faces, the authors reported more effective detection of angry than happy faces. This angry advantage was most obvious for highly socially anxious individuals when their social fear was experimentally enhanced.