Brain activation, affect, and aerobic exercise: An examination of both state-independent and state-dependent relationships

Resting electroencephalograph (EEG) asymmetry is a biological marker of the propensity to respond affectively to, and a measure of change in affect associated with, acute aerobic exercise. This study examined the EEG-affect–exercise relationship. Twenty participants performed each of three randomly assigned 30-min conditions: (a) a nonexercise control, (b) a cycling exercise at 55% VO₂max, and (c) a cycling exercise at 70% VO₂max. EEG and affect were assessed pre- and 0, 5, 10, 20, and 30 min postcondition. No significant results were seen in the control or 55% conditions. In the 70% exercise condition, greater relative left frontal activation preexercise predicted increased positive affect and reduced state anxiety postexercise. Participants (n= 7) with extreme relative left frontal activation post-exercise reported concomitant decreases in anxiety, whereas participants (n= 7) with extreme relative right frontal activation postexercise reported increases in anxiety. These findings (a) replicate prior work, (b) suggest a dose-response intensity effect, and (c) support the idea that exercise is an emotion-eliciting event. Affective responses seem to be mediated in part by differential resting levels of activation in the anterior brain regions. Ongoing anterior brain activation reflected concurrent postexercise affect.     

Regional brain activity and strenuous exercise: predicting affective responses using EEG asymmetry

Previous research using the model proposed by Davidson has shown that resting frontal electroencephalographic (EEG) asymmetry can predict affective responses to aerobic exercise at moderate intensities. Specifically, greater relative left frontal activity has been shown to predict positive affect (i.e., energy) following exercise. The purpose of this study was to determine if resting frontal EEG asymmetry would predict affective responses following strenuous exercise. Thirty participants (13 women, 17 men) completed a maximal graded exercise test on a treadmill. EEG was recorded prior to exercise. Affect was measured by the Activation Deactivation Adjective Check List prior to the graded exercise test, immediately following, 10 and 20-min following exercise. Greater relative left frontal activity predicted tiredness and calmness during recovery from exercise, but not tension or energy. Tiredness and calmness following exercise covaried, suggesting that tiredness following exercise might not have been linked with displeasure. These findings offer further support for the link between EEG asymmetry and affective responses to exercise.     

Regional brain activation and affective response to physical activity among healthy adolescents

Research has shown that frontal brain activation, assessed via electroencephalographic (EEG) asymmetry, predicts the post-exercise affective response to exercise among adults. Building on this evidence, the present study investigates the utility of resting cortical asymmetry for explaining variance in the affective response both during and after exercise at two different intensities among healthy adolescents. Resting EEG was obtained from 98 adolescents (55% male), who also completed two 30-min exercise tasks on a cycle ergometer at a moderate and hard intensity. Affect (as measured by the Feeling Scale) was assessed prior to exercise, every 10 min during exercise, immediately post-exercise, and 10 min post-exercise. When moderate exercise was performed first, resting frontal cortical asymmetry was related to the affective response to moderate exercise, such that left-dominant adolescents reported more positive affect compared to right-dominant adolescents. When hard exercise was performed first, the association was not significant. The results are interpreted in light of current theory related to affect in response to exercise.     

Predicting affective responses to exercise using resting EEG frontal asymmetry: Does intensity matter?

Affective responses to exercise may be important for improving adherence to regular programs of exercise. The present study sought to determine whether resting frontal EEG asymmetry, an individual difference measure of affective style, is predictive of affective responses to exercise performed at distinct intensities standardized relative to a metabolic landmark (i.e., the ventilatory threshold, VT). Resting EEG was collected from 30 participants and used to predict affective responses following treadmill running at three exercise intensities: below-VT, at-VT, and above-VT. Affect was assessed [via Activation-Deactivation Adjective Check List, yielding measures of Energetic Arousal (EA) and Tense Arousal (TA)] before, immediately following exercise, after 5 min cool down, and 10 and 20 min post-cool down. Resting mid-frontal asymmetry (F4-F3) significantly predicted EA immediately following below-VT exercise; resting lateral frontal asymmetry (F8-F7) predicted EA at 20 min post-cool down. Resting mid-frontal asymmetry predicted in EA immediately following and following cool down in above-VT exercise. As a whole, frontal asymmetry was predictive of affective responses following exercise, namely greater relative left frontal activity predicting lower EA. This was opposite to the predictions of the valenced motivation model, but may provide some support for the motivation direction model. This is based on the fact that low EA could be indicative of approach motivation, especially at higher exercise intensities.     

Frontal brain asymmetry and affective style: A conceptual replication

Recent studies have demonstrated that positive and negative affective reactivity can be predicted by resting electroencephalographic (EEG) asymmetry in frontal brain regions. These studies used different methods to assess asymmetry and affectivity. The goal of the present study was a conceptual replication of these results and to investigate their independence of employed procedures. Resting EEG of 37 subjects was recorded and affective slides were presented to obtain ratings of subjects' emotional reactions. Different procedures were applied to the data to assess the relation between asymmetries and affective reactivity. Depending on the particular analysis procedure, there were associations between anterior asymmetry and affectivity in line with the published findings, opponent to those findings, or no relation between anterior asymmetry and affective reactivity.     

Frontal brain asymmetry and transient cardiovascular responses to the perception of humor

The study examined the relationship of individual differences in prefrontal brain asymmetry, measured by the EEG in resting conditions, to the individual's responsivity in the context of humor (n = 42). Several weeks after the EEG recording, immediate cardiovascular responses to the perception of humor and behavioral indicators of humor processing were obtained in an experimental paradigm involving non-verbal cartoons. Relatively greater resting activity in the left than right prefrontal cortex, particularly at the ventrolateral positions, was associated with faster detection of humor, a more pronounced cardiac response to the perception of humor (heart rate and cardiac output), and more accessible internal positive affective states (indicated by faster reports of amusement levels). The study confirms and extends findings of the relevance of prefrontal brain asymmetry to affective responsivity, contributing evidence in the domain of positive affect and humor, and demonstrating relationships to the immediate cardiovascular response pattern to an emotional event.     

Frontal EEG asymmetry and symptom response to cognitive behavioral therapy in patients with social anxiety disorder

Although previous studies have shown that socially anxious individuals exhibit greater relative right frontal electroencephalogram (EEG) activity at rest, no studies have investigated whether improvements in symptoms as a result of treatment are associated with concomitant changes in resting brain activity. Regional EEG activity was measured at rest in 23 patients with social anxiety disorder (SAD) before and after cognitive behavioral therapy (CBT). Results indicated that patients shifted significantly from greater relative right to greater relative left resting frontal brain activity from pre- to posttreatment. Greater left frontal EEG activity at pretreatment predicted greater reduction in social anxiety from pre- to posttreatment and lower posttreatment social anxiety after accounting for pretreatment symptoms. These relations were specific to the frontal alpha EEG asymmetry metric. These preliminary findings suggest that resting frontal EEG asymmetry may be a predictor of symptom change and endstate functioning in SAD patients who undergo efficacious psychological treatment.     

Prefrontal asymmetry predicts affect, but not beliefs about affect

Self-reported emotional feelings are easily biased by situational or identity-related beliefs. Such biases vary as a function of memory. Recent memories draw more on veridical felt affective experience whereas distant memories draw more on situational or identity-related biases. For this study, frontal EEG asymmetry was used to predict feeling- versus belief-based self-reports of freshmen year homesickness in college freshmen and sophomores. Relatively greater right frontal EEG asymmetry predicted greater feeling-based, experiential reports of freshman year homesickness, whereas no associations were found between frontal EEG asymmetry and belief-based, retrospective reports of freshman year homesickness. These results support the status of frontal EEG asymmetry as a measure of affective vulnerability and suggest that links between frontal EEG asymmetry and self-reported affect are detectable to the extent that self-reports capture current emotional feelings and not situational or identity-related beliefs about what one ought to have felt.     

Influence of a brief aerobic training program on heart rate and subjective response to a psychologic stressor

An experiment was conducted to determine whether a brief program of aerobic exercise would reduce the heart rate and subjective responses of high- and low-fit subjects to a psychologic stressor. Thirty-four high-fit and 34 low-fit subjects were exposed to a moderate stressor (recall of digits backwards test) while their heart rates and subjective responses were monitored. Approximately half of the high- and low-fit subjects then participated in a 13-week aerobic exercise training program, whereas the other subjects did not. After the 13-week period, the subjects were again exposed to the stressor. Results indicated that a) in the pretest the low-fit subjects showed a greater heart rate response to the stressor than the high-fit subjects, b) the training program was effective for increasing subjects' levels of aerobic fitness, and c) the training program was effective for reducing the heart rate response to the stressor of low-fit subjects. These findings provide support for the relationship between fitness and the response to psychologic stressors and they suggest that aerobic training may be an effective way of helping low-fit persons deal with psychologic stressors.     

Frontal brain asymmetry and affective flexibility in an emotional contagion paradigm

This study was aimed at examining the relation of an individual's EEG asymmetry in the lateral frontal cortex, assessed in resting conditions, to affective flexibility. An auditory paradigm was used to induce negative (sad) and positive (cheerful) affective states, and state-dependent shifts of dorsolateral EEG asymmetry in response to and after the emotional provocations were observed. A Left>Right activation pattern at rest was associated with a shift to the right during negative and a shift to the left during positive stimulation, and efficient recovery after negative stimulation. Right>Left participants appeared unresponsive to both sounds. Distinct and differentiated responses to provocation with negative and positive affect and efficient recovery suggest that Left>Right prefrontal activity at rest is related to a flexible pattern of affective responding, which has been linked to adaptive emotional processing in the relevant literature.     

A capability model of individual differences in frontal EEG asymmetry

Researchers interested in measuring individual differences in affective style via asymmetries in frontal brain activity have depended almost exclusively upon the resting state for EEG recording. This reflects an implicit conceptualization of affective style as a response predisposition that is manifest in frontal EEG asymmetry, with the goal to describe individuals in terms of their general approach or withdrawal tendencies. Alternatively, the response capability conceptualization seeks to identify individual capabilities for approach versus withdrawal responses during emotionally salient events. The capability approach confers a variety of advantages to the study of affective style and personality, and suggests new possibilities for the approach/withdrawal motivational model of frontal EEG asymmetry and emotion. Logical as well as empirical arguments supportive of this conclusion are presented.     

The relation of cortical activity and BIS/BAS on the trait level

The behavioral activation system (BAS) and the behavioral inhibition system (BIS) have been proposed to be related to anterior asymmetry in the BIS/BAS model of anterior asymmetry. As an alternative, it may be suggested that behavioral activation comprises approach and withdrawal motivation and that the BAS is related to bilateral frontal trait activity. The aim of the present study was an empirical investigation on the relation between cortical trait activity, BIS and BAS. Data of 59 subjects on four occasions were analyzed. On each occasion, cortical activity was evaluated with resting EEG, and the BIS and BAS strength was assessed with questionnaires. Subjects with greater bilateral frontal cortical activity showed higher BAS scores. The latter result may suggest that behavioral activation comprises approach and withdrawal motivation.     

Resting frontal brain activity: linkages to maternal depression and socio-economic status among adolescents

We tested the prediction that resting frontal brain asymmetry would be a marker of vulnerability for depression among adolescents. Baseline electroencephalographic (EEG) activity was recorded from 12 to 14-year-old adolescents whose mothers had a history of depression (high risk group) and whose mothers were lifetime-free of axis I psychopathology (low risk group). High risk adolescents demonstrated the hypothesized pattern of relative left frontal hypo-activity on alpha-band measures. Such effects were specific to the mid-frontal region and generally consistent across reference montages. Socio-economic status (SES) also predicted alpha asymmetry. When the effects of SES and risk status were jointly assessed, SES contributed unique variance to the prediction of frontal brain asymmetry. The implications of the observed relations among maternal depression, SES, and frontal brain asymmetry are discussed.     

Trajectories of resting frontal brain activity and psychopathology in female adolescents exposed to child maltreatment

Resting frontal electroencephalogram (EEG) alpha asymmetry patterns reflecting different affective and motivational tendencies have been proposed as a putative mechanism underlying resilience among maltreated youth. This 2‐year prospective study examined whether developmental stability of resting frontal alpha asymmetry moderated the relation between child maltreatment severity and psychopathology in female adolescents (n = 43; ages 12–16) recruited from child protection agencies. Results identified two trajectories of resting frontal asymmetry: 60.5% displayed stable right and 39.5% displayed stable left frontal alpha asymmetry. Although individuals with these alpha asymmetry profiles experienced comparable childhood trauma severity, adolescents with stable left alpha asymmetry and lower levels of trauma were less likely to present symptoms or an episode of posttraumatic stress disorder (PTSD) and depression over 2 years than those with stable right alpha asymmetry and lower levels of trauma. These findings suggest that developmental patterns of resting left frontal brain activity may buffer against psychopathology in maltreated female youth.     

Trait affect moderates cortical activation in response to state affect.

To examine the influence of trait affect on cortical activation during state affect, 32 healthy female participants viewed video clips to induce positive and negative emotional states. Frontal and parietal electroencephalogram (EEG) of the alpha band was assessed while participants imagined the scene of each video that generated the most intense emotions. The results showed that affect-induced frontal asymmetry was moderated by negative trait affect. The difference in frontal asymmetry between positive and negative state affect increased linearly with negative trait affect. Moreover, positive trait affect was negatively correlated with activation in the right-parietal brain region. These results suggest that trait affect moderates the effects of state affect on brain activation.     

Right frontal brain activity,cortisol, and withdrawal behavior in 6-month-old infants

Although several studies have examined anterior asymmetric brain electrical activity and cortisol in infants, children, and adults, the direct association between asymmetry and cortisol has not systematically been reported. In nonhuman primates, greater relative right anterior activation has been associated with higher cortisol levels. The current study examines the relation between frontal electroencephalographic (EEG) asymmetry and cortisol (basal and reactive) and withdrawal-related behaviors (fear and sadness) in 6-month-old infants. As predicted, the authors found that higher basal and reactive cortisol levels were associated with extreme right EEG asymmetry. EEG during the withdrawal-negative affect task was associated with fear and sadness behaviors. Results are interpreted in the context of the previous primate work, and some putative mechanisms are discussed.     

Neural correlates of posttraumatic growth after severe motor vehicle accidents

Frontal brain asymmetry has been associated with emotion- and motivation-related constructs. The authors examined the relationship between frontal brain asymmetry and subjective perception of posttraumatic growth (PTG) after severe motor vehicle accidents (MVAs). Eighty-two survivors of MVAs completed self-report measures of PTG, trait and state affect, and diagnostic interviews assessing clinical status, and underwent measurement of resting electroencephalographic activity. As predicted, increased relative left frontal activation was significantly related to PTG, even when statistically controlling for dispositional positive affect. The authors assume that approach-related motivational tendencies associated with higher relative left frontal brain activity may be involved in the process and outcome of PTG.     

P300, N400, aerobic fitness, and maximal aerobic exercise

Electrophysiological effects of aerobic fitness and maximal aerobic exercise were investigated by comparing P300 and N400 before and after a maximal cycling test. Event-related potentials (ERPs) were obtained from 20 students divided into two matched groups defined by their aerobic fitness level (cyclists vs. sedentary subjects). The session of postexercise ERPs was performed immediately after body temperature and heart rate returned to preexercise values. At rest, no significant differences were observed in ERP parameters between cyclists and sedentary subjects. This finding argued against the hypothesis that ERP modifications may be directly assumed by aerobic fitness level. The postexercise session of ERPs showed a significant P300 amplitude increase and a significant P300 latency decrease in all subjects. Similarly, N400 effect increased significantly after the maximal exercise in all subjects. ERP changes were of the same magnitude in the two groups. The present study argues for a general arousing effect of maximal aerobic exercise, independently of the aerobic fitness level.     

Resting and task‐elicited prefrontal EEG alpha asymmetry in depression: Support for the capability model

The capability model of frontal electroencephalographic (EEG) asymmetry suggests that brain activity during emotional challenge will be a more powerful indicator of predispositions toward psychopathology than activity observed at rest. EEG data were assessed during a resting baseline and a facial emotion task, wherein individuals with (n = 143) and without (n = 163) lifetime major depressive disorder (MDD) made approach (angry and happy) and withdrawal (afraid and sad) facial expressions. EEG asymmetry during emotional challenge was a more powerful indicator of MDD status than resting asymmetry for average, Cz, and linked mastoid references, results in support of the capability model. However, current‐source‐density (CSD) transformed asymmetry was indicative of lifetime MDD status under resting and task‐elicited conditions. Findings suggest that CSD‐transformed data may be more robust indicators of trait frontal EEG asymmetry.     

正常成年人额叶静息脑电alpha波偏侧化的年龄差异

目的 采用静息脑电技术研究正常成年人额叶alpha波偏侧化是否受到年龄因素的影响,同时进一步验证静息脑电alpha波偏侧化作为情绪调节能力指标的稳定性.方法 正常青年人（18～ 25岁）30人,正常中年人（40 ～ 50岁）30人,首先采集脑电,对脑电数据进行离线分析,将最终数据转化成自然对数,然后用SPSS 17.0软件处理,对两组人群进行分析.结果 正常成年人额叶静息脑电Alpha波存在偏侧化（F =6.865,P＜0.05）.青年组与中年组额叶静息脑电在F3/F4点（t=-0.346,P＞0.05）;F7/F8点（t=-0.121,P＞0.05）;FP1/FP2点的偏侧化程度均不存在差异（t=-0.192,P＞0.05）.结论 正常成年人额叶静息脑电偏侧化不受年龄因素影响,额叶静息脑电Alpha波偏侧化作为情绪调节能力的指标在年龄差异上具有一定的稳定性.