The psychological, neurochemical and functional neuroanatomical mediators of the effects of positive and negative mood on executive functions

Cumulative activation during positive and negative events and state anxiety predicts subsequent inertia of amygdala reactivity

Inertia, together with intensity and valence, is an important component of emotion. We tested whether positive and negative events generate lingering changes in subsequent brain responses to unrelated threat stimuli and investigated the impact of individual anxiety. We acquired fMRI data while participants watched positive or negative movie-clips and subsequently performed an unrelated task with fearful and neutral faces. We quantified changes in amygdala reactivity to fearful faces as a function of the valence of preceding movies and cumulative neural activity evoked during them. We demonstrate that amygdala responses to emotional movies spill over to subsequent processing of threat information in a valence-specific manner: negative movies enhance later amygdala activation whereas positive movies attenuate it. Critically, the magnitude of such changes is predicted by a measure of cumulative amygdala responses to the preceding positive or negative movies. These effects appear independent of overt attention, are regionally limited to amygdala, with no changes in functional connectivity. Finally, individuals with higher state anxiety displayed stronger modulation of amygdala reactivity by positive movies. These results suggest that intensity and valence of emotional events as well as anxiety levels promote local changes in amygdala sensitivity to threat, highlighting the importance of past experience in shaping future affective reactivity.

The Brussels Mood Inductive Audio Stories (MIAS) database

Through this study, we aimed to validate a new tool for inducing moods in experimental contexts. Five audio stories with sad, joyful, frightening, erotic, or neutral content were presented to 60 participants (33 women, 27 men) in a within-subjects design, each for about 10 min. Participants were asked (1) to report their moods before and after listening to each story, (2) to assess the emotional content of the excerpts on various emotional scales, and (3) to rate their level of projection into the stories. The results confirmed our a priori emotional classification. The emotional stories were effective in inducing the desired mood, with no difference found between male and female participants. These stories therefore constitute a valuable corpus for inducing moods in French-speaking participants, and they are made freely available for use in scientific research.

Replication of the correlation between natural mood states and working memory-related prefrontal activity measured by near-infrared spectroscopy in a German sample

Previous studies have suggested complex interactions of mood and cognition in the lateral prefrontal cortex (PFC). Although such interactions might be influenced by various factors such as personality and cultural background, their reproducibility and generalizability have hardly been explored. In the present study, we focused on a previously found correlation between negative mood states and PFC activity during a verbal working memory (WM) task, which had been demonstrated by using near-infrared spectroscopy (NIRS) in a Japanese sample. To confirm and extend the generalizability of this finding, we conducted a similar experiment in a German sample, i.e., participants with a different language background. Here, PFC activity during verbal and spatial WM tasks was measured by NIRS using a delayed match-to-sample paradigm after the participants' natural mood states had been evaluated by a mood questionnaire (Profiles of Mood States: POMS). We also included control tasks to consider the general effect of visual/auditory inputs and motor responses. For the verbal WM task, the POMS total mood disturbance (TMD) score was negatively correlated with baseline-corrected NIRS data mainly over the left dorsolateral PFC (i.e., higher TMD scores were associated with reduced activation), which is consistent with previous studies. Moreover, this relationship was also present when verbal WM activation was contrasted with the control task. These results suggest that the mood–cognition interaction within the PFC is reproducible in a sample with a different language background and represents a general phenomenon.

Intraindividual variability in domain-specific cognition and risk of mild cognitive impairment and dementia

Intraindividual variability among cognitive domains may predict dementia independently of interindividual differences in cognition. A multidomain cognitive battery was administered to 2305 older adult women (mean age 74 years) enrolled in an ancillary study of the Women's Health Initiative. Women were evaluated annually for probable dementia and mild cognitive impairment (MCI) for an average of 5.3 years using a standardized protocol. Proportional hazards regression showed that lower baseline domain-specific cognitive scores significantly predicted MCI (N = 74), probable dementia (N = 45), and MCI or probable dementia combined (N = 101) and that verbal and figural memory predicted each outcome independently of all other cognitive domains. The baseline intraindividual standard deviation across test scores (IAV Cognitive Domains) significantly predicted probable dementia and this effect was attenuated by interindividual differences in verbal episodic memory. Slope increases in IAV Cognitive Domains across measurement occasions (IAV Time) explained additional risk for MCI and MCI or probable dementia, beyond that accounted for by interindividual differences in multiple cognitive measures, but risk for probable dementia was attenuated by mean decreases in verbal episodic memory slope. These findings demonstrate that within-person variability across cognitive domains both at baseline and longitudinally independently accounts for risk of cognitive impairment and dementia in support of the predictive utility of within-person variability.

Music, affect, method, data: reflections on the Carroll versus Kivy debate

The comprehensive exchange between Noel Carroll and Peter Kivy, which took place in 2007, addressed key issues in the relationship between music and affect. More than in any prior philosophical debate on this topic, experimental psychologists' methods and data played a significant role. However, to a nontrivial extent, the findings-perhaps especially the dubious-were misconstrued or misused, usually without acknowledging the existence of contrary data-based opinion within the psychology of music itself. Therefore, one objective of the present article is to identify the specific problematic features and shed light on the broader context shared by the two disciplines. A complementary goal is to examine contributions to philosophers' transgressions by music psychologists' insufficiently conscientious reporting, frequent overgeneralizations, and unawareness of philosophers' critical arguments. Another objective is to examine the current status of key concepts-the relevant music, basic emotions, mood, expression, induction, movement and dance, and methods (including introspection and experimental procedures)-thus perhaps enabling the discussion of music and affect to proceed with fewer misunderstandings. Finally, the article moves beyond the initial debate and builds on a remarkable agreement of philosophical and psychological opinion on a key issue (the induction of non-basic emotions by absolute music) to reach a new conceptual ground.

Effects of arginine vasopressin on musical working memory

Previous genetic studies showed an association between variations in the gene coding for the 1a receptor of the neuro-hormone arginine vasopressin (AVP) and musical working memory (WM). The current study set out to test the influence of intranasal administration (INA) of AVP on musical as compared to verbal WM using a double blind crossover (AVP—placebo) design. Two groups of 25 males were exposed to 20 IU of AVP in one session, and 20 IU of saline water (placebo) in a second session, 1 week apart. In each session subjects completed the tonal subtest from Gordon's “Musical Aptitude Profile,” the interval subtest from the “Montreal Battery for Evaluation of Amusias (MBEA),” and the forward and backward digit span tests. Scores in the digit span tests were not influenced by AVP. In contrast, in the music tests there was an AVP effect. In the MBEA test, scores for the group receiving placebo in the first session (PV) were higher than for the group receiving vasopressin in the first session (VP) (p < 0.05) with no main Session effect nor Group × Session interaction. In the Gordon test there was a main Session effect (p < 0.05) with scores higher in the second as compared to the first session, a marginal main Group effect (p = 0.093) and a marginal Group × Session interaction (p = 0.88). In addition we found that the group that received AVP in the first session scored higher on scales indicative of happiness, and alertness on the positive and negative affect scale, (PANAS). Only in this group and only in the music test these scores were significantly correlated with memory scores. Together the results reflect a complex interaction between AVP, musical memory, arousal, and contextual effects such as session, and base levels of memory. The results are interpreted in light of music's universal use as a means to modulate arousal on the one hand, and AVP's influence on mood, arousal, and social interactions on the other.

Electrophysiological evidence for emotional valence and competitive arousal effects on insight problem solving

Accumulating evidence suggests that insight can be substantially influenced by task-irrelevant emotion stimuli and interpersonal competitive situation, and a close link might exist between them. Using a learning-testing paradigm and Event-Related Potentials (ERPs), the present study investigated the independent and joint effects of emotional and competitive information on insight problem solving especially their neural mechanisms. Subjects situated in either competitive or non-competitive condition learned heuristic logogriphs first and then viewed task-irrelevant positive or negative emotional pictures, which were followed by test logogriphs to solve. Both behavioral and ERP findings showed a more evident insight boost following negative emotional pictures in competitive context. Results demonstrated that negative emotion and competitive situation might promote insight by a defocused mode of attention (as indicated by N1 and P2), the enhanced semantic integration and breaking mental set (as indicated by N450), and the increased forming of novel associations activated by motivational arousal originating from competition (as indicated by P800-1600 and P1600-2500). These results indicate that the dynamic interactions between emotional valence and competitive arousal effects on insight.

How about lunch? Consequences of the meal context on cognition and emotion

Although research addresses the effects of a meal’s context on food preference, the psychological consequences of meal situations are largely unexplored. We compared the cognitive and emotional effects of a restaurant meal eaten in the company of others to a solitary meal consumed in a plain office using pre- and post-tests analysis and controlling for the kind and amount of food consumed. Three tasks were conducted, measuring: (1) semantic memory (2) cognitive control and error monitoring, and (3) processing of emotional facial expressions. Covert processes in these tasks were assessed with event-related brain potentials. A mood rating questionnaire indicated a relaxation effect of the restaurant as compared to the plain meal situation. The restaurant meal increased sensitivity to threatening facial expressions and diminished cognitive control and error monitoring. No effects were observed for semantic memory. These findings provide the first experimental evidence that a restaurant meal with a social component may be more relaxing than a meal eaten alone in a plain setting and may reduce cognitive control.

Automatic classification of eye activity for cognitive load measurement with emotion interference

Measuring cognitive load changes can contribute to better treatment of patients, can help design effective strategies to reduce medical errors among clinicians and can facilitate user evaluation of health care information systems. This paper proposes an eye-based automatic cognitive load measurement (CLM) system toward realizing these prospects. Three types of eye activity are investigated: pupillary response, blink and eye movement (fixation and saccade). Eye activity features are investigated in the presence of emotion interference, which is a source of undesirable variability, to determine the susceptibility of CLM systems to other factors. Results from an experiment combining arithmetic-based tasks and affective image stimuli demonstrate that arousal effects are dominated by cognitive load during task execution. To minimize the arousal effect on CLM, the choice of segments for eye-based features is examined. We then propose a feature set and classify three levels of cognitive load. The performance of cognitive load level prediction was found to be close to that of a reaction time measure, showing the feasibility of eye activity features for near-real time CLM.

Correlation between prefrontal cortex activity during working memory tasks and natural mood independent of personality effects: an optical topography study

Interactions between mood and cognition have drawn much attention in the fields of psychology and neuroscience. Recent neuroimaging studies have examined a neural basis of the mood-cognition interaction that which emphasize the role of the prefrontal cortex (PFC). Although these studies have shown that natural mood variations among participants are correlated with PFC activity during cognitive tasks, they did not control for personality differences. Our aim in this study was to clarify the relationship between natural mood and PFC activity by partialling out the effects of personality. Forty healthy adults completed self-report questionnaires assessing natural mood (the Profile of Mood States) and personality (the NEO Five-Factor Inventory and the Behavioral Inhibition/Activation Systems scales). They performed verbal and spatial working memory (WM) tasks while their PFC activity was measured using optical topography, a non-invasive, low-constraint neuroimaging tool. Correlation analysis showed that the level of negative mood was inversely associated with PFC activity during the verbal WM task, which replicated our previous findings. Furthermore, the negative correlation between negative mood and PFC activity remained significant after controlling for participants' personality traits, suggesting that natural mood is an independent contributing factor of PFC activity during verbal WM tasks.

Side effects of being blue: influence of sad mood on visual statistical learning

It is well established that mood influences many cognitive processes, such as learning and executive functions. Although statistical learning is assumed to be part of our daily life, as mood does, the influence of mood on statistical learning has never been investigated before. In the present study, a sad vs. neutral mood was induced to the participants through the listening of stories while they were exposed to a stream of visual shapes made up of the repeated presentation of four triplets, namely sequences of three shapes presented in a fixed order. Given that the inter-stimulus interval was held constant within and between triplets, the only cues available for triplet segmentation were the transitional probabilities between shapes. Direct and indirect measures of learning taken either immediately or 20 minutes after the exposure/mood induction phase revealed that participants learned the statistical regularities between shapes. Interestingly, although participants from the sad and neutral groups performed similarly in these tasks, subjective measures (confidence judgments taken after each trial) revealed that participants who experienced the sad mood induction showed increased conscious access to their statistical knowledge. These effects were not modulated by the time delay between the exposure/mood induction and the test phases. These results are discussed within the scope of the robustness principle and the influence of negative affects on processing style.

Cognitive enhancement as a treatment for drug addictions

Drug addiction continues to be an important public health problem, with an estimated 22.6 million current illicit drug users in the United States alone. For many addictions, including cocaine, methamphetamine, and marijuana addiction, there are no approved pharmacological treatments. Behavioral treatments are effective but effects vary widely across individuals. Treatments that are effective across multiple addictions are greatly needed, and accumulating evidence suggests that one such approach may be pharmacological or behavioral interventions that enhance executive inhibitory control in addicts. Current evidence indicates that most forms of chronic drug use may be associated with significant cognitive impairments, especially in attention, working memory, and response inhibition functions. In some studies, these impairments predict poor treatment retention and outcome. A number of cognitive enhancing agents, including galantamine, modafinil, atomoxetine, methylphenidate, and guanfacine, have shown promising findings in human studies. Specific behavioral interventions, including cognitive remediation, also show promise. However, whether improvement of selective cognitive functions reduces drug use behavior remains to be determined. Cognitive enhancement to improve treatment outcomes is a novel strategy worthy of future research, as are related questions such as whether these approaches may be broadly beneficial to most addicts or best reserved for substance users with specific demonstrated cognitive impairments. This article is part of a Special Issue entitled 'Cognitive Enhancers'.

Feelings of helplessness increase ERN amplitudes in healthy individuals

Experiencing feelings of helplessness has repeatedly been reported to contribute to depressive symptoms and negative affect. In turn, depression and negative affective states are associated, among others, with impairments in performance monitoring. Thus, the question arises whether performance monitoring is also affected by feelings of helplessness.

To this end, after the induction of feelings of helplessness via an unsolvable reasoning task, 37 participants (20 females) performed a modified version of a Flanker task. Based on a previously validated questionnaire, 17 participants were classified as helpless and 20 as not-helpless. Behavioral measures revealed no differences between helpless and not-helpless individuals. However, we observed enhanced Error-Related Negativity (ERN) amplitude differences between erroneous and correct responses in the helpless compared to the not-helpless group. Furthermore, correlational analysis revealed that higher scores of helplessness were associated with increased ERN difference scores. No influence of feelings of helplessness on later stages of performance monitoring was observed as indicated by Error-Positivity (Pe) amplitude.

The present study is the first to demonstrate that feelings of helplessness modulate the neuronal correlates of performance monitoring. Thus, even a short-lasting subjective state manipulation can lead to ERN amplitude variation, probably via modulation of mesencephalic dopamine activity.

Positive and negative affect, depression, and cognitive processes in the Cognition in the Study of Tamoxifen and Raloxifene (Co-STAR) Trial

OBJECTIVES

This study examined the relationship between positive and negative affect, depressive symptoms, and cognitive performance.

METHODS

The sample consisted of 1479 non-demented, postmenopausal women (mean age = 67 years) at increased risk of breast cancer enrolled in the National Surgical Adjuvant Breast and Bowel Project's Study of Tamoxifen and Raloxifene. At each annual visit, women completed a standardized neuropsychological battery and self-report measures of affect and depression. Data from three visits were used in linear mixed models for repeated measures using likelihood ratio tests. Separate analyses were performed to relate positive/negative affect and depression to each cognitive measure.

RESULTS

Higher positive affect was associated with better letter fluency (p = .006) and category fluency (p < .0001). Higher negative affect was associated with worse global cognitive function (p < .0001), verbal memory (CVLT List B; p = .002), and spatial ability (p < .0001). Depressive symptoms were negatively associated with verbal knowledge (p = .004), figural memory (p < .0001), and verbal memory (p's ≤ .0001).

DISCUSSION

Findings are consistent with some prior research demonstrating a link between positive affect and increased verbal fluency and between depressive symptoms and decreased memory. The most novel finding shows that negative affect is related to decreased global cognition and visuospatial ability. Overall, this research in a large, longitudinal sample supports the notion that positive affect is related to increases and negative affect to decreases in performance on distinct cognitive measures.

On the interaction between sad mood and cognitive control: the effect of induced sadness on electrophysiological modulations underlying Stroop conflict processing

The present study employed high-density ERPs to examine the effect of induced sad mood on the spatiotemporal correlates of conflict monitoring and resolution in a colour-word Stroop interference task. Neuroimaging evidence and dipole modelling implicates the involvement of the anterior cingulate cortex (ACC) and medial prefrontal cortex (mPFC) regions in conflict-laden interference control. On the basis that these structures have been found to mediate emotion-cognition interactions in negative mood states, it was predicted that Stroop-related cognitive control, which relies heavily on anterior neural sources, would be affected by effective sad mood provocation. Healthy participants (N=14) were induced into transient sadness via use of autobiographical sad scripts, a well-validated mood induction technique (Liotti et al., 2000a, 2002). In accord with previous research, interference effects were shown at both baseline and sad states while Stroop conflict was associated with early (N450) and late (Late Positive Component; LPC) electrophysiological modulations at both states. Sad mood induction attenuated the N450 effect in line with our expectation that it would be susceptible to modulation by mood, given its purported anterior limbic source. The LPC effect was displayed at the typical posterior lateral sites but, as predicted, was not affected by sad mood. However, frontocentral LPC activity-presumably generated from an additional anterior limbic source-was affected at sad state, hinting a role in conflict monitoring. Although the neurophysiological underpinnings of interference control are yet to be clarified, this study provided further insight into emotion-cognition interactions as indexed by Stroop conflict-laden processing.

Happily distracted: mood and a benefit of attention dysregulation in older adults

Positive mood states are believed to broaden the focus of attention in younger adults, but it is unclear whether the same is true for older adults. Here we examined one consequence of broader attention that has been shown in young adults: that memory for distraction is greater for those in a positive mood. In the current study, positive and neutral moods were induced in older adults (M = 67.9) prior to a 1-back task in which participants were instructed to attend to relevant pictures and ignore distracting words. Following a 10-min filled interval, participants performed a word fragment completion task that tested implicit memory for the distracting words from the 1-back task. Older adults in the positive mood group showed greater implicit memory for previous distraction compared to those in the neutral mood group. These findings suggest that affect influences the ability to regulate attention in a similar manner for younger and older adults.

Differential effects of emotionally versus neutrally cued autobiographical memories on performance of a subsequent cognitive task: effects of task difficulty

Attention is a limited resource, and in order to improve processing of the attended information, competing processes must be suppressed. Although it is well established that an experimentally induced change in mood state comprises one type of competing process that can impair performance on a subsequent task, no study has investigated whether an emotionally valenced autobiographical memory (AM) also can alter performance on a subsequent task. We therefore examined the effects of AM recall on cognitive performance. Healthy participants (n = 20 per experiment) recalled AMs in response to positive, negative, and neutral cue words. Following each AM participants completed a simple perceptual task (Experiment 1) or solved moderately difficult subtraction problems (Experiment 2). In Experiment 1 participants performed less accurately following exposure to positive or negative versus neutral cue words (ps < 0.001), and also were less accurate following negative versus positive cue words (p < 0.001). In Experiment 2, in contrast, no difference in accuracy or response times reached statistical significance. Performance accuracy even trended toward being higher following exposure to negative versus neutral cue words (p = 0.08). The results of Experiment 1 suggested that recalling emotionally salient AMs reduces the attention directed toward a simple continuous performance task administered immediately following the AM task, conceivably due to persistent contemplation of the AM. The negative results of Experiment 2 suggested that the effect of AMs on attention was attenuated, however, by increasing the difficulty of the subsequent task. Our results have implications for patients with major depressive disorder (MDD), as performing cognitively demanding tasks may allow them to attenuate the impairing effects of negative rumination on cognition.

Which aspects of executive dysfunction influence ability to manage diabetes in older adults?

AIMS

To examine whether different aspects of executive function as measured by different assessment tools are associated with glycaemic control and other clinical characteristics in older adults with Type 2 diabetes.

METHODS

We performed a cross-sectional study of older adults aged ≥ 70 years with Type 2 diabetes at a tertiary care diabetes centre. The Dysexecutive Questionnaire was used to measure self-reported executive dysfunction. Objective tests of executive functions included a modified clock drawing test (Clock-in-a-Box), Trail Making Tests (parts A and B) and verbal fluency. Demographic and clinical information was collected using questionnaires and surveys. Glycaemic control was measured by HbA(1c).

RESULTS

We evaluated 145 patients [average age 77 ± 5 years, diabetes duration 15 ± 11 years, mean HbA(1c) 56 ± 11 mmol/mol (7.3 ± 1.1%)]. Poor performances on objective tests (low scores on Clock-in-a-Box and verbal fluency; and high scores on Trail Making Tests A and B) but not on the subjective test (the Dysexecutive Questionnaire), were associated with poor glycaemic control (r = -0.23, P < 0.005; r = -0.17, P < 0.04; r = 0.20, P < 0.01, r = 0.22, P < 0.008, r = -0.07, P < 0.42, respectively). In a multiple regression model (r(2) = 0.39), high Dysexecutive Questionnaire scores were associated with higher diabetes-related distress (P < 0.0004), depressive symptoms (P < 0.004), number of falls (P < 0.009), fear of falling (P < 0.01), less years of education (P < 0.0007) and fewer medications (P < 0.001).

CONCLUSIONS

On the one hand, in older adults, executive dysfunction detected by objective tests is associated with poor glycaemic control and may be considered before prescribing complex treatment regimens. On the other hand, self-reported executive dysfunction is associated with risk and fear of falls, and more affective symptoms, which may indicate higher awareness of subtle deficits.

Differential effects of emotionally versus neutrally cued autobiographical memories on performance of a subsequent cognitive task: effects of task difficulty

Attention is a limited resource, and in order to improve processing of the attended information, competing processes must be suppressed. Although it is well established that an experimentally induced change in mood state comprises one type of competing process that can impair performance on a subsequent task, no study has investigated whether an emotionally valenced autobiographical memory (AM) also can alter performance on a subsequent task. We therefore examined the effects of AM recall on cognitive performance. Healthy participants (n = 20 per experiment) recalled AMs in response to positive, negative, and neutral cue words. Following each AM participants completed a simple perceptual task (Experiment 1) or solved moderately difficult subtraction problems (Experiment 2). In Experiment 1 participants performed less accurately following exposure to positive or negative versus neutral cue words (ps < 0.001), and also were less accurate following negative versus positive cue words (p < 0.001). In Experiment 2, in contrast, no difference in accuracy or response times reached statistical significance. Performance accuracy even trended toward being higher following exposure to negative versus neutral cue words (p = 0.08). The results of Experiment 1 suggested that recalling emotionally salient AMs reduces the attention directed toward a simple continuous performance task administered immediately following the AM task, conceivably due to persistent contemplation of the AM. The negative results of Experiment 2 suggested that the effect of AMs on attention was attenuated, however, by increasing the difficulty of the subsequent task. Our results have implications for patients with major depressive disorder (MDD), as performing cognitively demanding tasks may allow them to attenuate the impairing effects of negative rumination on cognition.

Depressed mood enhances anxiety to unpredictable threat

BACKGROUND

Depression and anxiety disorders (ADs) are highly co-morbid, but the reason for this co-morbidity is unclear. One possibility is that they predispose one another. An informative way to examine interactions between disorders without the confounds present in patient populations is to manipulate the psychological processes thought to underlie the pathological states in healthy individuals. In this study we therefore asked whether a model of the sad mood in depression can enhance psychophysiological responses (startle) to a model of the anxiety in ADs. We predicted that sad mood would increase anxious anxiety-potentiated startle responses.

METHOD

In a between-subjects design, participants (n=36) completed either a sad mood induction procedure (MIP; n=18) or a neutral MIP (n=18). Startle responses were assessed during short-duration predictable electric shock conditions (fear-potentiated startle) or long-duration unpredictable threat of shock conditions (anxiety-potentiated startle).

RESULTS

Induced sadness enhanced anxiety- but not fear-potentiated startle.

CONCLUSIONS

This study provides support for the hypothesis that sadness can increase anxious responding measured by the affective startle response. This, taken together with prior evidence that ADs can contribute to depression, provides initial experimental support for the proposition that ADs and depression are frequently co-morbid because they may be mutually reinforcing.

How the emotional content of discourse affects language comprehension

Emotion effects on cognition have often been reported. However, only few studies investigated emotional effects on subsequent language processing, and in most cases these effects were induced by non-linguistic stimuli such as films, faces, or pictures. Here, we investigated how a paragraph of positive, negative, or neutral emotional valence affects the processing of a subsequent emotionally neutral sentence, which contained either semantic, syntactic, or no violation, respectively, by means of event-related brain potentials (ERPs). Behavioral data revealed strong effects of emotion; error rates and reaction times increased significantly in sentences preceded by a positive paragraph relative to negative and neutral ones. In ERPs, the N400 to semantic violations was not affected by emotion. In the syntactic experiment, however, clear emotion effects were observed on ERPs. The left anterior negativity (LAN) to syntactic violations, which was not visible in the neutral condition, was present in the negative and positive conditions. This is interpreted as reflecting modulatory effects of prior emotions on syntactic processing, which is discussed in the light of three alternative or complementary explanations based on emotion-induced cognitive styles, working memory, and arousal models. The present effects of emotion on the LAN are especially remarkable considering that syntactic processing has often been regarded as encapsulated and autonomous.

The relationship between flow, sleepiness and cognitive performance: the effects of short afternoon nap and bright light exposure

"Flow" is a positive emotional state which typically occurs when a person perceives a balance between the challenges associated with a situation and his or her capabilities to accomplish these demands. While flow often occurs along with positive feelings and high introspective performance, only a few studies have investigated how it is associated with cognitive performance (i.e., objective performance). In the present study, we investigated the relationship between flow, emotions, and cognitive performance. A short nap (20 min) and bright light (>2,000 lux) techniques were used as experimental manipulations to enhance flow. Fifteen participants (31.3 ± 7.19 yr old) took part in four experimental conditions: rest, short nap, bright light, and nap and bright light. Pearson's correlation coefficients were calculated for flow and other indices using standardized data. Results showed that flow scores significantly increased after a short nap and under bright light exposure. The correlations between flow and reaction time were also significant. Flow was significantly associated with positive emotion and sleepiness. These results suggest that a short nap and bright light can be employed as a flow facilitator and that flow status can be used as an indicator in evaluating work efficiency and occupational mental health.

Interactions between mood and the structure of semantic memory: event-related potentials evidence

Recent evidence suggests that affect acts as modulator of cognitive processes and in particular that induced mood has an effect on the way semantic memory is used on-line. We used event-related potentials (ERPs) to examine affective modulation of semantic information processing under three different moods: neutral, positive and negative. Fifteen subjects read 324 pairs of sentences, after mood induction procedure with 30 pictures of neutral, 30 pictures of positive and 30 pictures of neutral valence: 108 sentences were read in each mood induction condition. Sentences ended with three word types: expected words, within-category violations, and between-category violations. N400 amplitude was measured to the three word types under each mood induction condition. Under neutral mood, a congruency (more negative N400 amplitude for unexpected relative to expected endings) and a category effect (more negative N400 amplitude for between- than to within-category violations) were observed. Also, results showed differences in N400 amplitude for both within- and between-category violations as a function of mood: while positive mood tended to facilitate the integration of unexpected but related items, negative mood made their integration as difficult as unexpected and unrelated items. These findings suggest the differential impact of mood on access to long-term semantic memory during sentence comprehension.

Factors associated with sustained attention during an activity intervention in persons with dementia

BACKGROUND/AIMS

Are the noncognitive factors of self-reported mood and personality related to sustained attention in nursing home residents with dementia during an activity intervention?

METHODS

Intervention data from a randomized clinical trial were used to address the aim of this project. Subjects were 128 nursing home residents who were assessed for mood, personality, behavioral indicators of attention, time on task and number of disengagements during an activity intervention.

RESULTS

More positive self-reported mood was associated with greater behavioral displays of attention during activities, greater time spent engaged in the activities and less disengagement.

CONCLUSION

To our knowledge, this is the first study to report on the association of mood, personality and sustained attention in nursing home residents with dementia. While the findings are preliminary, they can be used to inform the design of future research.

Correlation of within-individual fluctuation of depressed mood with prefrontal cortex activity during verbal working memory task: optical topography study

Previous studies showed that interindividual variations in mood state are associated with prefrontal cortex (PFC) activity. In this study, we focused on the depressed-mood state under natural circumstances and examined the relationship between within-individual changes over time in this mood state and PFC activity. We used optical topography (OT), a functional imaging technique based on near-infrared spectroscopy, to measure PFC activity for each participant in three experimental sessions repeated at 2-week intervals. In each session, the participants completed a self-report questionnaire of mood state and underwent OT measurement while performing verbal and spatial working memory (WM) tasks. The results showed that changes in the depressed-mood score between successive sessions were negatively correlated with those in the left PFC activation for the verbal WM task (ρ = -0.56, p < 0.05). In contrast, the PFC activation for the spatial WM task did not co-vary with participants' mood changes. We thus demonstrated that PFC activity during a verbal WM task varies depending on the participant's depressed mood state, independent of trait factors. This suggests that using optical topography to measure PFC activity during a verbal WM task can be used as a potential state marker for an individual's depressed mood state.

The influence of positive mood on different aspects of cognitive control

Some evidence suggests that positive mood influences cognitive control. The current research investigated whether positive mood has differential effects on two aspects of cognitive control, working memory and prepotent response inhibition. In Study 1, following either a positive or neutral mood induction, participants completed the Running Memory Span (RMS), a measure primarily of working memory storage capacity, and the Stroop task, a measure of prepotent response inhibition. Results were that the positive mood group performed worse on the RMS task but not on the Stroop task. In Study 2, participants completed the RMS and another measure of prepotent response inhibition, the Flanker task. Results were that when in a positive mood state participants performed worse on the RMS but not on the Flanker task. Overall, this research suggests that positive mood has differential effects on cognitive control, impairing working memory but having no effect on prepotent response inhibition.

Emotion processing facilitates working memory performance

The effect of emotional stimulus content on working memory performance has been investigated with conflicting results, as both emotion-dependent facilitation and impairments are reported in the literature. To clarify this issue, 52 adult participants performed a modified visual 2-back task with highly arousing positive stimuli (sexual scenes), highly arousing negative stimuli (violent death) and low-arousal neutral stimuli. Emotional stimulus processing was found to facilitate task performance relative to that of neutral stimuli, both in regards to response accuracy and reaction times. No emotion-dependent differences in false-alarm rates were found. These results indicate that emotional information can have a facilitating effect on working memory maintenance and processing of information.

Relationship of negative mood with prefrontal cortex activity during working memory tasks: an optical topography study

Mood has a substantial impact on cognitive functions. Although studies have shown that the interaction between mood and cognition is mediated by the prefrontal cortex (PFC), little is known about how naturalistic mood in everyday life is associated with PFC activity during cognitive tasks. We investigated whether inter-individual variation in perceived mood under current life situations (recent week) is related to PFC activity during working memory (WM) tasks in healthy adults. Levels of positive and negative moods were quantified with the Profile of Mood States (POMS) questionnaire. PFC activities during verbal and spatial WM tasks were measured by optical topography (OT), a non-invasive low-constraint neuroimaging tool, to minimize experimental intervention in participants' moods. Group-average analysis showed significant activations in the bilateral dorsolateral PFC in both WM tasks. Correlation analysis revealed that the participants reporting higher levels of negative moods showed lower levels of PFC activity during the verbal WM task but not during the spatial WM task. This relationship was significant even after controlling for possible confounding factors such as age, gender, and task performance. Our results suggest that verbal WM is linked with naturalistic negative mood and that the PFC is involved in the mood-cognition interaction in daily circumstances.

Pleasant mood intensifies brain processing of cognitive control: ERP correlates

The present study investigated the impact of auditory-induced mood on brain processing of cognitive control using a Stroop color-word interference task. A total of 135 positive, negative, and neutral sounds (45 of each) were presented in separate blocks for a mood induction procedure, which was then followed by a Stroop color-word task in each trial. Event-related potentials (ERPs) were recorded for color-word congruent, incongruent and neutral (color-word irrelevant) words and subjects named the printed colors of the words by pressing the appropriate key (irrespective of word meaning). Response latency was delayed during incongruent vs. neutral trials, and this cost did not interact significantly with mood states. ERP data showed prolonged peak latencies in the P200 component and more negative deflections in the Late Positive Component (LPC, 450-550 ms) during incongruent vs. neutral conditions, regardless of mood states. Moreover, the negative deflections (N450) in the 450-550 ms interval of the incongruent- neutral difference waves, which index cognitive control effect in brain potentials, was more pronounced in the pleasant, but not in the unpleasant, mood state when compared with the neutral mood state. These data suggest that, pleasant mood intensifies brain processing of cognitive control, in a situation requiring effective inhibition of task-irrelevant distracting information. In addition, N450 component serves as an affective marker, embodying not only cognitive control effect in the brain but also its interaction with mood states.

Emotions in cognitive conflicts are not aversive but are task specific

It has been suggested that cognitive conflicts require effortful processing and, therefore, are aversive (Botvinick, 2007). In the present study, we compared conflicts emerging from the inhibition of a predominant response tendency in a go/no-go task with those between incompatible response activations in a Simon task in a within-subjects design, using the same type of stimuli. Whereas no-go trials elicited reduced skin conductance and pupillometric responses, but prolonged corrugator muscle activity, as compared with go trials, incompatible and compatible Simon trials were indistinguishable with respect to these parameters. Furthermore, the conflict-sensitive N2 components of the event-related brain potential were similar in amplitude, but showed significantly different scalp distributions, indicating dissociable neural generator systems. The present findings suggest the involvement of different emotional and cognitive processes in both types of cognitive conflicts-none being aversive, however. In addition, the N2 findings call into question claims of common monitoring systems for all kinds of cognitive conflicts.

Intra- and interindividual differences in lateralized cognitive performance and asymmetrical EEG activity in the frontal cortex

The study shows that changes in relative verbal vs. figural working memory and fluency performance from one session to a second session two to 3 weeks apart covary with spontaneously occurring changes of cortical asymmetry in the lateral frontal and central cortex, measured by electroencephalography (EEG) in resting conditions before the execution of tasks. That is, it was examined whether the current state of cortical asymmetry predicts verbal vs. figural performance. The findings complete the circle from studies showing correlations between changes of EEG asymmetry in the lateral frontal cortex and changes of mood to studies showing correlations between changes of mood and changes of relative verbal vs. figural working memory and fluency performance. The study suggests that state-dependent changes of lateralized cortical activity may underlie certain cognitive-emotional interactions observed in previous studies, and supports the assumption of reciprocal influences of specific emotional and specific cognitive processes.

Overview of non-pharmacological intervention for dementia and principles of brain-activating rehabilitation

Non-pharmacological interventions for dementia are likely to have an important role in delaying disease progression and functional decline. Research into non-pharmacological interventions has focused on the differentiation of each approach and a comparison of their effects. However, Cochrane Reviews on non-pharmacological interventions have noted the paucity of evidence regarding the effects of these interventions. The essence of non-pharmacological intervention is dependent of the patients, families, and therapists involved, with each situation inevitably being different. To obtain good results with non-pharmacological therapy, the core is not 'what' approach is taken but 'how' the therapists communicate with their patients. Here, we propose a new type of rehabilitation for dementia, namely brain-activating rehabilitation, that consists of five principles: (i) enjoyable and comfortable activities in an accepting atmosphere; (ii) activities associated with empathetic two-way communication between the therapist and patient, as well as between patients; (iii) therapists should praise patients to enhance motivation; (iv) therapists should try to offer each patient some social role that takes advantage of his/her remaining abilities; and (v) the activities should be based on errorless learning to ensure a pleasant atmosphere and to maintain a patient's dignity. The behavioral and cognitive status is not necessarily a reflection of pathological lesions in the brain; there is cognitive reserve for improvement. The aim of brain-activating rehabilitation is to enhance patients' motivation and maximize the use of their remaining function, recruiting a compensatory network, and preventing the disuse of brain function. The primary expected effect is that patients recover a desire for life, as well as their self-respect. Enhanced motivation can lead to improvements in cognitive function. Amelioration of the behavioral and psychological symptoms of dementia and improvements in activities of daily living can also be expected due to the renewed positive attitude towards life. In addition, improvements in the quality of life for both patients and caregivers is an expected outcome. To establish evidence for non-pharmacological interventions, research protocols and outcome measures should be standardized to facilitate comparison among studies, as well as meta-analysis.

Upward spirals of positive emotions counter downward spirals of negativity: insights from the broaden-and-build theory and affective neuroscience on the treatment of emotion dysfunctions and deficits in psychopathology

This review integrates Fredrickson's broaden-and-build theory of positive emotions with advances in affective neuroscience regarding plasticity in the neural circuitry of emotions to inform the treatment of emotion deficits within psychopathology. We first present a body of research showing that positive emotions broaden cognition and behavioral repertoires, and in so doing, build durable biopsychosocial resources that support coping and flourishing mental health. Next, by explicating the processes through which momentary experiences of emotions may accrue into self-perpetuating emotional systems, the current review proposes an underlying architecture of state-trait interactions that engenders lasting affective dispositions. This theoretical framework is then used to elucidate the cognitive-emotional mechanisms underpinning three disorders of affect regulation: depression, anxiety, and schizophrenia. In turn, two mind training interventions, mindfulness and loving-kindness meditation, are highlighted as means of generating positive emotions that may counter the negative affective processes implicated in these disorders. We conclude with the proposition that positive emotions may exert a countervailing force on the dysphoric, fearful, or anhedonic states characteristic of psychopathologies typified by emotional dysfunctions.

Better Mood and Better Performance

Theories of mood and its effect on cognitive processing suggest that positive mood may allow for increased cognitive flexibility. This increased flexibility is associated with the prefrontal cortex and the anterior cingulate cortex, both of which play crucial roles in hypothesis testing and rule selection. Thus, cognitive tasks that rely on behaviors such as hypothesis testing and rule selection may benefit from positive mood, whereas tasks that do not rely on such behaviors should not be affected by positive mood. We explored this idea within a category-learning framework. Positive, neutral, and negative moods were induced in our subjects, and they learned either a rule-described or a non-rule-described category set. Subjects in the positive-mood condition performed better than subjects in the neutral- or negative-mood conditions in classifying stimuli from rule-described categories. Positive mood also affected the strategy of subjects who classified stimuli from non-rule-described categories.

Effects of aversive odour presentation on inhibitory control in the Stroop colour-word interference task

Background

Due to the unique neural projections of the olfactory system, odours have the ability to directly influence affective processes. Furthermore, it has been shown that emotional states can influence various non-emotional cognitive tasks, such as memory and planning. However, the link between emotional and cognitive processes is still not fully understood. The present study used the olfactory pathway to induce a negative emotional state in humans to investigate its effect on inhibitory control performance in a standard, single-trial manual Stroop colour-word interference task. An unpleasant (H₂S) and an emotionally neutral (Eugenol) odorant were presented in two separate experimental runs, both in blocks alternating with ambient air, to 25 healthy volunteers, while they performed the cognitive task.

Results

Presentation of the unpleasant odorant reduced Stroop interference by reducing the reaction times for incongruent stimuli, while the presentation of the neutral odorant had no effect on task performance.

Conclusions

The odour-induced negative emotional state appears to facilitate cognitive processing in the task used in the present study, possibly by increasing the amount of cognitive control that is being exerted. This stands in contrast to other findings that showed impaired cognitive performance under odour-induced negative emotional states, but is consistent with models of mood-congruent processing.

The effects of mind-body training on stress reduction, positive affect, and plasma catecholamines

This study was designed to assess the association between stress, positive affect and catecholamine levels in meditation and control groups. The meditation group consisted of 67 subjects who regularly engaged in mind-body training of "Brain-Wave Vibration" and the control group consisted of 57 healthy subjects. Plasma catecholamine (norepinephrine (NE), epinephrine (E), and dopamine (DA)) levels were measured, and a modified form of the Stress Response Inventory (SRI-MF) and the Positive Affect and Negative Affect Scale (PANAS) were administered. The meditation group showed higher scores on positive affect (p=.019) and lower scores on stress (p<.001) compared with the control group. Plasma DA levels were also higher in the meditation (p=.031) than in the control group. The control group demonstrated a negative correlation between stress and positive affects (r=-.408, p=.002), whereas this correlation was not observed in the meditation group. The control group showed positive correlations between somatization and NE/E (r=.267, p=.045) and DA/E (r=.271, p=.042) ratios, whereas these correlations did not emerge in the meditation group. In conclusion, these results suggest that meditation as mind-body training is associated with lower stress, higher positive affect and higher plasma DA levels when comparing the meditation group with the control group. Thus, mind-body training may influence stress, positive affect and the sympathetic nervous system including DA activity.