Motivational mechanisms (BAS) and prefrontal cortical activation contribute to recognition memory for emotional words. rTMS effect on performance and EEG (alpha band) measures (original) (raw)
Related papers
Neuroscience, 2015
The present research explored the cortical correlates of emotional memories in response to words and pictures. Subjects' performance (Accuracy Index, AI; response times, RTs; RTs/AI) was considered when a repetitive Transcranial Magnetic Stimulation (rTMS) was applied on the left dorsolateral prefrontal cortex (LDLPFC). Specifically, the role of LDLPFC was tested by performing a memory task, in which old (previously encoded targets) and new (previously not encoded distractors) emotional pictures/words had to be recognized. Valence (positive vs. negative) and arousing power (high vs. low) of stimuli were also modulated. Moreover, subjective evaluation of emotional stimuli in terms of valence/arousal was explored. We found significant performance improving (higher AI, reduced RTs, improved general performance) in response to rTMS. This "better recognition effect" was only related to specific emotional features, that is positive high arousal pictures or words. Moreover no...
Emotion-Modulated Performance and Activity in Left Dorsolateral Prefrontal Cortex
Emotion, 2005
Functional MRI (fMRI) was used to examine the relationship between processing of pleasant and unpleasant stimuli and activity in prefrontal cortex. Twenty volunteers identified the colors in which pleasant, neutral, and unpleasant words were printed. Pleasant words prompted more activity bilaterally in dorsolateral prefrontal cortex (DLPFC) than did unpleasant words. In addition, pleasant words prompted more activity in left than in right DLPFC. Response speed to pleasant words was correlated with DLPFC activity. These data directly link positive affect, enhanced performance, and prefrontal activity, providing some of the first fMRI evidence supporting models of emotional valence and frontal brain asymmetry based on electroencephalography (EEG).
2008
Contemporary dimensional models of emotion regard the positive to negative valence dimension as an important organising principle. This principle has been used to organise empirical observations of the relationship between left vs. right (asymmetrical) frontal cortical activations and positive vs. negative emotional experience and expression. This affective valence organising principle has also been used in research concerned with how emotions affect cognition, and much research has suggested that positive affects have different effects on cognition than negative affects. In this paper, we review recent research that questions the utility of the affective valence dimension in understanding the functions of asymmetrical frontal cortical activity and in understanding the effects of emotions on cognition. We will show that the incorporation of motivational direction as a separate dimension from affective valence will benefit understanding of brain mechanisms involved in emotions as well as emotion-cognition interactions. (Netherlands Journal of Psychology, 64,(132)(133)(134)(135)(136)(137)(138)(139)(140)(141)(142) Contemporary dimensional models of emotion regard the positive to negative valence dimension as an important organising principle . Over the last three decades, this principle has been used to organise empirical observations of the relationship between left vs. right (asymmetrical) frontal cortical activations and emotional experience and expression. In this body of research, positive affect has been found to relate to relatively greater left than right frontal cortical activity, whereas negative affect has been found to relate to relatively greater right than left frontal cortical activity. This affective valence organising principle has also been used in research concerned with how emotions affect cognition, and much research has suggested that positive affects have different effects on cognition than negative affects. In this paper, we will review research that questions the utility of the affective valence dimension in understanding the functions of asymmetrical frontal cortical activity and in understanding the effects of emotions on cognition. We will show that the incorporation of motivational direction
Cognitive control of emotional processing is essential for adaptive human behavior. Biased attention toward emotionally salient information is critically linked with affective disorders and is discussed as a promising treatment target. Anodal (activity enhancing) transcranial direct current stimulation (tDCS) has been shown to increase healthy and impaired cognitive control over emotional distraction and is therefore widely used for the investigation and experimental treatment of this disorder. In this study, event-related potential (ERP) were recorded parallel to tDCS to track its online effects. Healthy volunteers (n = 87) performed a delayed working memory paradigm with emotional salient and neutral distractors during stimulation with different intensities (sham, 0.5, 1, 1.5 mA). Measuring the late positive potential (LPP), an ERP that indexes attention allocation, we found that a valence-specific increase of the early portion of the LPP (eLPP, 250–500 ms) was associated with less emotional distraction in the sham group. Of note, stimulation with tDCS exerted an intensity related effect on this correlation. The later part of the LPP (lLPP, 500–1000 ms) was found to be correlated with reaction time, regardless of valence. General effect of tDCS on LPPs and task performance were not observed. These findings demonstrate that ERP recordings parallel to tDCS are feasible to investigate the neuronal underpinnings of stimulation effects on executive functions. Furthermore, they support the notion that the LPP induced by a distractive stimulus during a working memory task mirrors the additional allocation of neuronal resources with a specific sensitivity of the early LPP for highly arousing negative stimuli. Finally, together with the variable magnitude and direction of the emotional bias, the lack of systematic modulations of LPPs and behavior by tDCS further underlines the important influence of the individual brain activity patterns on stimulation effects both on the behavioral and neurophysiological level.
PLoS ONE, 2013
The hedonic meaning of words affects word recognition, as shown by behavioral, functional imaging, and event-related potential (ERP) studies. However, the spatiotemporal dynamics and cognitive functions behind are elusive, partly due to methodological limitations of previous studies. Here, we account for these difficulties by computing combined electromagnetoencephalographic (EEG/MEG) source localization techniques. Participants covertly read emotionally high-arousing positive and negative nouns, while EEG and MEG were recorded simultaneously. Combined EEG/MEG current-density reconstructions for the P1 (80-120 ms), P2 (150-190 ms) and EPN component (200-300 ms) were computed using realistic individual head models, with a cortical constraint. Relative to negative words, the P1 to positive words predominantly involved language-related structures (left middle temporal and inferior frontal regions), and posterior structures related to directed attention (occipital and parietal regions). Effects shifted to the right hemisphere in the P2 component. By contrast, negative words received more activation in the P1 time-range only, recruiting prefrontal regions, including the anterior cingulate cortex (ACC). Effects in the EPN were not statistically significant. These findings show that different neuronal networks are active when positive versus negative words are processed. We account for these effects in terms of an ''emotional tagging'' of word forms during language acquisition. These tags then give rise to different processing strategies, including enhanced lexical processing of positive words and a very fast language-independent alert response to negative words. The valence-specific recruitment of different networks might underlie fast adaptive responses to both approach-and withdrawal-related stimuli, be they acquired or biological. Citation: Keuper K, Zwitserlood P, Rehbein MA, Eden AS, Laeger I, et al. (2013) Early Prefrontal Brain Responses to the Hedonic Quality of Emotional Words -A Simultaneous EEG and MEG Study. PLoS ONE 8(8): e70788.
The present study investigated whether the right hemisphere preponderance of stimulus-preceding negativity (SPN) was affected by different categories of visual feedback stimulus. A time estimation task was performed with facial, verbal, symbolic, and no-feedback conditions. A principal component analysis identified an early component of SPN in addition to a late component that was morphologically similar to the original SPN. Motivational scores in the verbal and facial conditions were higher than that in the symbolic condition. Significant right hemisphere preponderance of the late SPN was observed in the symbolic condition but not in the verbal condition, whereas right hemisphere preponderance of the early SPN was observed in the facial condition. The right hemisphere preponderance was influenced by the category of visual feedback stimulus through stimulus-related activation and the effect of the motivational level. Stimulus-preceding negativity (SPN) is a negative nonmotoric slow potential reflecting anticipation, which is recorded before the presentation of a feedback (FB) stimulus during a time estimation task (Brunia, 1988; Brunia & Damen, 1988; Damen & Brunia, 1987). SPN does not necessarily occur before all types of stimuli; its emergence requires a stimulus that contains a particular meaning to perform the experimental task (Chwilla & Brunia, 1991). A right-lateralized distribution is a characteristic of SPN (Damen & Brunia, 1987, 1994) that has been observed in various SPN studies (Brunia
PLOS ONE, 2015
We distinguish two evaluative systems which evoke automatic and reflective emotions. Automatic emotions are direct reactions to stimuli whereas reflective emotions are always based on verbalized (and often abstract) criteria of evaluation. We conducted an electroencephalography (EEG) study in which 25 women were required to read and respond to emotional words which engaged either the automatic or reflective system. Stimulus words were emotional (positive or negative) and neutral. We found an effect of valence on an early response with dipolar fronto-occipital topography; positive words evoked a higher amplitude response than negative words. We also found that topographically specific differences in the amplitude of the late positive complex were related to the system involved in processing. Emotional stimuli engaging the automatic system were associated with significantly higher amplitudes in the left-parietal region; the response to neutral words was similar regardless of the system engaged. A different pattern of effects was observed in the central region, neutral stimuli engaging the reflective system evoked a higher amplitudes response whereas there was no system effect for emotional stimuli. These differences could not be reduced to effects of differences between the arousing properties and concreteness of the words used as stimuli.
We report here a study that obtained reliable effects of emotional modulation of a well-known index of memory encodingthe electrophysiological "Dm" effectusing a recognition memory paradigm followed by a source memory task. In this study, participants performed an old-new recognition test of emotionally negative and neutral pictures encoded 1 day before the test, and a source memory task involving the retrieval of the temporal context in which pictures had been encoded. Our results showed that Dm activity was enhanced for all emotional items on a late positivity starting at $ 400 ms poststimulus onset, although Dm activity for high arousal items was also enhanced at an earlier stage (200-400 ms). Our results also showed that emotion enhanced Dm activity for items that were both recognised with or without correct source information. Further, when only high arousal items were considered, larger Dm amplitudes were observed if source memory was accurate. Three main conclusions are drawn from these findings. First, negative emotion can enhance encoding processes predicting the subsequent recognition of central item information. Second, if emotion reaches high levels of arousal, the encoding of contextual details can also be enhanced over and above the effects of emotion on central item encoding. Third, the morphology of our ERPs is consistent with a hybrid model of the role of attention in emotion-enhanced memory (Pottage and Schaefer, 2012).
Two routes to emotional memory: Distinct neural processes for valence and arousal
Proceedings of the National Academy of Sciences, 2004
Prior investigations have demonstrated that emotional information is often better remembered than neutral information, but they have not directly contrasted effects attributable to valence and those attributable to arousal. By using functional MRI and behavioral studies, we found that distinct cognitive and neural processes contribute to emotional memory enhancement for arousing information versus valenced, nonarousing information. The former depended on an amygdalar-hippocampal network, whereas the latter was supported by a prefrontal cortex-hippocampal network implicated in controlled encoding processes. A behavioral companion study, with a divided-attention paradigm, confirmed that memory enhancement for valenced, nonarousing words relied on controlled encoding processes: concurrent task performance reduced the enhancement effect. Enhancement for arousing words occurred automatically, even when encoding resources were diverted to the secondary task. W hy do we remember some experiences while forgetting others? Neuroimaging has provided a tool to probe this question. By comparing the neural activity during encoding of items that are later remembered versus those that are later forgotten (a ''subsequent memory'' analysis), one can examine the processes mediating successful encoding (i.e., that are carried out during encoding of words that will later be remembered; reviewed in ref. 1). Functional MRI studies have indicated that activation in prefrontal cortex (PFC), hippocampus, and parahippocampal gyrus underlies successful encoding, such that greater activation in these regions increases the probability that information will be remembered.
Journal of Cognitive Neuroscience, 2005
& We examined how responses to aversive pictures affected performance and stimulus-locked event-related potentials (ERPs) recorded during a demanding cognitive task. Numeric Stroop stimuli were briefly presented to either left or right visual hemifield (LVF and RVF, respectively) after a centrally presented aversive or neutral picture from the International Affective Picture System. Subjects indicated whether a quantity value from each Stroop stimulus matched the preceding Stroop stimulus while passively viewing the pictures. After aversive pictures, responses were more accu-rate for LVF Stroops and less accurate for RVF Stroops. Early-latency extrastriate attention-dependent visual ERPs were enhanced for LVF Stroops. The N2 ERP was enhanced for LVF Stroops over the right frontal and parietal scalp sites. Slow potentials (300-800 msec) recorded over the frontal and parietal regions showed enhanced picture related modulation and amplitude for LVF Stroops. These results suggest that emotional responses to aversive pictures selectively facilitated right hemisphere processing during higher cognitive task performance. &