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Age-Dependent ERP Correlates of Emotional Episodic Memory  [PDF]
Brigitta Tóth, Roland Boha, Zsófia Kardos, Bálint File, Márk Molnár
Psychology (PSYCH) , 2016, DOI: 10.4236/psych.2016.76082
Abstract:

The effect of aging was studied on emotional word recognition processes. In an episodic memory task young (18 - 26 years, N = 44) and elderly (60 - 71 years N = 47) adults were instructed to memorize a set of emotional words while EEG recording was performed. Memory performance was measured by a recognition test. The N400 and late positive complex (LPC) event-related potential components elicited by new and old words were analyzed. Decreased recognition accuracy and slower reaction time were found in the elderly irrespective of stimulus valence, except for correct rejection of neutral words, where the difference between age groups was not significant. The old/ new effect on the N400 was more robust in the young but for the LPC was more conspicuous in the elderly. The effect of valence observed for negative words was more pronounced in the young both in the earlier (N400) and later (LPC) latency ranges. The findings with respect to the old/new effect indicate prioritized processing of aversive stimuli in the young and may correspond to diminished capacity of adaptive behavior in the elderly.

Emotional Valence and the Free-Energy Principle  [PDF]
Mateus Joffily ,Giorgio Coricelli
PLOS Computational Biology , 2013, DOI: 10.1371/journal.pcbi.1003094
Abstract: The free-energy principle has recently been proposed as a unified Bayesian account of perception, learning and action. Despite the inextricable link between emotion and cognition, emotion has not yet been formulated under this framework. A core concept that permeates many perspectives on emotion is valence, which broadly refers to the positive and negative character of emotion or some of its aspects. In the present paper, we propose a definition of emotional valence in terms of the negative rate of change of free-energy over time. If the second time-derivative of free-energy is taken into account, the dynamics of basic forms of emotion such as happiness, unhappiness, hope, fear, disappointment and relief can be explained. In this formulation, an important function of emotional valence turns out to regulate the learning rate of the causes of sensory inputs. When sensations increasingly violate the agent's expectations, valence is negative and increases the learning rate. Conversely, when sensations increasingly fulfil the agent's expectations, valence is positive and decreases the learning rate. This dynamic interaction between emotional valence and learning rate highlights the crucial role played by emotions in biological agents' adaptation to unexpected changes in their world.
How Emotional Mechanism Helps Episodic Learning in a Cognitive Agent  [PDF]
Usef Faghihi,Philippe Fournier-Viger,Roger Nkambou,Pierre Poirier,Andre Mayers
Computer Science , 2009,
Abstract: In this paper we propose the CTS (Concious Tutoring System) technology, a biologically plausible cognitive agent based on human brain functions.This agent is capable of learning and remembering events and any related information such as corresponding procedures, stimuli and their emotional valences. Our proposed episodic memory and episodic learning mechanism are closer to the current multiple-trace theory in neuroscience, because they are inspired by it [5] contrary to other mechanisms that are incorporated in cognitive agents. This is because in our model emotions play a role in the encoding and remembering of events. This allows the agent to improve its behavior by remembering previously selected behaviors which are influenced by its emotional mechanism. Moreover, the architecture incorporates a realistic memory consolidation process based on a data mining algorithm.
The Effect of Retrieval Focus and Emotional Valence on the Medial Temporal Lobe Activity during Autobiographical Recollection  [PDF]
Ekaterina Denkova,Sanda Dolcos,Florin Dolcos
Frontiers in Behavioral Neuroscience , 2013, DOI: 10.3389/fnbeh.2013.00109
Abstract: Laboratory-based episodic memory studies, using micro-events (pictures/words), point to a role of the amygdala (AMY), an emotion-based region, in the encoding and retrieval of emotionally valenced memories. However, autobiographical memory (AM) studies, using real-life personal events, do not conclusively support AMY’s involvement in AM recollection. This could be due to differences in instructions across the AM studies – i.e., whether emotional aspects were explicitly emphasized or not. The present study investigated the effect of retrieval focus on activity in emotion (AMY) and memory (hippocampus – HC) based regions of the medial temporal lobe in 17 subjects, who remembered emotional AMs while event-related fMRI data were recorded. The retrieval focus was manipulated by instructions to focus either on emotional (Emotion condition) or on other contextual (Context condition) details of the recollected AMs. The effect of retrieval focus according to the valence of AMs was also investigated by involving an equal proportion of positive and negative AMs. There were four main findings, showing both similarities and differences in retrieving positive and negative AMs. Regarding similarities, (1) focusing on Emotion was associated with increased scores of subjective re-experience of emotion and increased activity in the left AMY, for both positive and negative AMs, compared to focusing on Context; (2) the subjective emotional ratings were also positively correlated with bilateral AMY activity for both positive and negative AMs. Regarding differences, (3) focusing on Emotion was associated with increased activity for positive but not for negative AMs in the right AMY, and with (4) opposing patterns of activity linked to the valence of AMs in the left HC – i.e., increased activity for positive and decreased activity for negative AMs. These findings shed light on the role of AMY and HC in emotional AM recollection, linked to the retrieval focus and the valence of memories.
Facial and semantic emotional interference: A pilot study on the behavioral and cortical responses to the dual valence association task
Agustín Ibá?ez, Esteban Hurtado, Rodrigo Riveros, Hugo Urquina, Juan F Cardona, Agustín Petroni, Alejandro Lobos-Infante, Joaquin Barutta, Sandra Baez, Facundo Manes
Behavioral and Brain Functions , 2011, DOI: 10.1186/1744-9081-7-8
Abstract: Behavioural measures and Event Related Potentials were recorded while participants performed the DVAT.Behavioural data showed a robust effect that distinguished compatible/incompatible tasks. The effects of valence and contextual association (between facial and semantic stimuli) showed early discrimination in N170 of faces. The LPP component was modulated by the compatibility of the DVAT.Results suggest that DVAT is a robust paradigm for studying the emotional interference effect in the processing of simultaneous information from semantic and facial stimuli.Integrating information about emotional valence from face expressions and semantic information is an essential aspect of social interactions. In particular, the integration of emotional cues in a highly associative context (e.g., face to face communication) is critical for understanding complex social cues. For example, to understand an irony, one benefits from integrating semantic information with facial clues that orient the listener to the opposite meaning. Language modulates the information presented in facial expressions [1], and in turn, emotion modulates semantic understanding [2]. In certain situations, the incompatibility of emotional cues regarding semantic information in an associative context requires cognitive processes in order to solve this conflict. In cognitive sciences, several paradigms are considered robust indexes of the degree of conflict, such as Simon effect, or interference between routes of divergent/convergent emotional information, such as Emotional Stroop effect. Conflict tasks, also known as interference tasks, present to the subject two or more tasks to be performed simultaneously. Each task requires the implementation of a limited number of maneuvers, which produces interference or conflict when one task is incongruent with another one.Here we present behavioural and neural correlates of an interference task, triggered by incongruent emotional discrimination, in a similar vein than
A Perfusion MRI Study of Emotional Valence and Arousal in Parkinson’s Disease  [PDF]
Sunsern Limsoontarakul,Meghan C. Campbell,Kevin J. Black
Parkinson's Disease , 2011, DOI: 10.4061/2011/742907
Abstract: Background. Brain regions subserving emotion have mostly been studied using functional magnetic resonance imaging (fMRI) during emotion provocation procedures in healthy participants. Objective. To identify neuroanatomical regions associated with spontaneous changes in emotional state over time. Methods. Self-rated emotional valence and arousal scores, and regional cerebral blood flow (rCBF) measured by perfusion MRI, were measured 4 or 8 times spanning at least 2 weeks in each of 21 subjects with Parkinson’s disease (PD). A random-effects SPM analysis, corrected for multiple comparisons, identified significant clusters of contiguous voxels in which rCBF varied with valence or arousal. Results. Emotional valence correlated positively with rCBF in several brain regions, including medial globus pallidus, orbital prefrontal cortex (PFC), and white matter near putamen, thalamus, insula, and medial PFC. Valence correlated negatively with rCBF in striatum, subgenual cingulate cortex, ventrolateral PFC, and precuneus—posterior cingulate cortex (PCC). Arousal correlated positively with rCBF in clusters including claustrum-thalamus-ventral striatum and inferior parietal lobule and correlated negatively in clusters including posterior insula—mediodorsal thalamus and midbrain. Conclusion. This study demonstrates that the temporal stability of perfusion MRI allows within-subject investigations of spontaneous fluctuations in mental state, such as mood, over relatively long-time intervals. 1. Background Even though Parkinson’s disease (PD) is a neurodegenerative disease defined by motor features [1], psychiatric sequelae are common such as depression, anxiety, and apathy [2, 3]. Previous studies have shown alteration of emotional processing in PD including reduced emotional physiologic response [4], impaired emotional word recognition [5], and impaired arousal judgment but normal valence [6]. The bulk of the evidence suggests that these changes result primarily from the degenerative process in the brain, and are not merely psychological reactions to disability [3]. Pathologically, Braak and Del Tredici [7] found that in PD clinical stages 1–3 (stage 4-5 pathologically), neurodegeneration could be seen in almost all areas of the brain including prefrontal cortex (PFC) and limbic system. Brain areas affected by PD that are hypothesized to cause emotional dysfunction including raphe nuclei, locus ceruleus, amygdala, mesolimbic, mesocortical, mesothalamic dopaminergic systems, and cingulate cortex [8]. Furthermore, neuroimaging studies have shown that a decrease in
Effect of Affect Induction Method on Emotional Valence and Arousal  [PDF]
Josef N. Lazar, Shiri Pearlman-Avnion
Psychology (PSYCH) , 2014, DOI: 10.4236/psych.2014.57070
Abstract:

Human functioning is influenced by the affective state. The literature contains several references to the possibility that valence and arousal have separable influences on attention. There are several methods of inducing affective state but the most popular are by music and video clips. The latter are more vivid and stimulate several sensory systems, leading to the hypothesis that a stronger effect will result when using video clips for the induction of affective state. Both methods have been used in many studies in the past but their different contributions have never really been tested. Thus the aim of the present study is to systematically establish or refute the assumption that video clips are the stronger tool for affect induction. In order to test this hypothesis a study was conducted in which 194 subjects participated in four groups. Positive and negative affect conditions were induced by validated music and video clips. The results established the validity of the hypothesis. The results should be applied in cognitive research testing the relations between induced affect and cognitive abilities in order to determine whether the effect is replicated when the cognitive abilities are tested.

The power of emotional valence—from cognitive to affective processes in reading  [PDF]
Ulrike Altmann,Isabel C. Bohrn,Oliver Lubrich,Arthur M. Jacobs
Frontiers in Human Neuroscience , 2012, DOI: 10.3389/fnhum.2012.00192
Abstract: The comprehension of stories requires the reader to imagine the cognitive and affective states of the characters. The content of many stories is unpleasant, as they often deal with conflict, disturbance or crisis. Nevertheless, unpleasant stories can be liked and enjoyed. In this fMRI study, we used a parametric approach to examine (1) the capacity of increasing negative valence of story contents to activate the mentalizing network (cognitive and affective theory of mind, ToM), and (2) the neural substrate of liking negatively valenced narratives. A set of 80 short narratives was compiled, ranging from neutral to negative emotional valence. For each story mean rating values on valence and liking were obtained from a group of 32 participants in a prestudy, and later included as parametric regressors in the fMRI analysis. Another group of 24 participants passively read the narratives in a three Tesla MRI scanner. Results revealed a stronger engagement of affective ToM-related brain areas with increasingly negative story valence. Stories that were unpleasant, but simultaneously liked, engaged the medial prefrontal cortex (mPFC), which might reflect the moral exploration of the story content. Further analysis showed that the more the mPFC becomes engaged during the reading of negatively valenced stories, the more coactivation can be observed in other brain areas related to the neural processing of affective ToM and empathy.
Brain Activations to Emotional Pictures are Differentially Associated with Valence and Arousal Ratings  [PDF]
Antje B. M. Gerdes,Matthias J. Wieser,Andreas Mühlberger,Peter Weyers,Georg W. Alpers,Michael M. Plichta,Felix Breuer,Paul Pauli
Frontiers in Human Neuroscience , 2010, DOI: 10.3389/fnhum.2010.00175
Abstract: Several studies have investigated the neural responses triggered by emotional pictures, but the specificity of the involved structures such as the amygdala or the ventral striatum is still under debate. Furthermore, only few studies examined the association of stimuli’s valence and arousal and the underlying brain responses. Therefore, we investigated brain responses with functional magnetic resonance imaging of 17 healthy participants to pleasant and unpleasant affective pictures and afterwards assessed ratings of valence and arousal. As expected, unpleasant pictures strongly activated the right and left amygdala, the right hippocampus, and the medial occipital lobe, whereas pleasant pictures elicited significant activations in left occipital regions, and in parts of the medial temporal lobe. The direct comparison of unpleasant and pleasant pictures, which were comparable in arousal clearly indicated stronger amygdala activation in response to the unpleasant pictures. Most important, correlational analyses revealed on the one hand that the arousal of unpleasant pictures was significantly associated with activations in the right amygdala and the left caudate body. On the other hand, valence of pleasant pictures was significantly correlated with activations in the right caudate head, extending to the nucleus accumbens (NAcc) and the left dorsolateral prefrontal cortex. These findings support the notion that the amygdala is primarily involved in processing of unpleasant stimuli, particularly to more arousing unpleasant stimuli. Reward-related structures like the caudate and NAcc primarily respond to pleasant stimuli, the stronger the more positive the valence of these stimuli is.
Determination of hemispheric emotional valence in individual subjects: A new approach with research and therapeutic implications
Fredric Schiffer, Martin H Teicher, Carl Anderson, Akemi Tomoda, Ann Polcari, Carryl P Navalta, Susan L Andersen
Behavioral and Brain Functions , 2007, DOI: 10.1186/1744-9081-3-13
Abstract: Probe auditory evoked potentials (AEP) recorded during a neutral and an upsetting memory were used to assess HEV in 28 (20 F) right-handed subjects who were either victims of childhood maltreatment (N = 12) or healthy controls. In a sub-population, we determined HEV by emotional response to lateral visual field stimulation (LVFS), in which vision is limited to one, then the other hemifield. We compare a number of morphometric and functional brain measures between individuals who have right-negative versus left-negative HEV.Using AEPs to determine HEV, we found 62% of controls and 67% of maltreated subjects had right negative HEV. There was a strong interaction between HEV-laterality and gender, which together accounted for 60% of individual variability in total grey matter volume (GMV). HEV-laterality was associated with differences in hippocampal volume, amygdala/hippocampal ratios, and measures of verbal, visual and global memory. HEV-laterality was associated also with different constellations of symptoms comparing maltreated subjects to controls. Emotional response to LVFS provided a convenient and complementary measure of HEV-laterality that correlated significantly with the HEVs determined by AEPs.Our findings suggest that HEV-laterality, like handedness or gender, is an important individual difference with significant implications for brain and behavioral research, and for guiding lateralized treatments such as rTMS.Sperry's split-brain studies have created an abiding interest in hemispheric differences in cognition [1]. There is also a vast literature on hemispheric differences in affect. At present there are three predominant hypotheses regarding hemispheric emotional valence (HEV). The first and earliest [2-5] states that the right hemisphere (RH) has a superiority over the left in processing emotions, especially negative emotions. The second model suggests [6] that the left frontal cortex is associated with positive, approach emotions and the right with n
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