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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., (Copyright © 2014 Society for Psychophysiological Research.)

Facial expressions are an important aspect of social interaction, conveying not only information regarding emotional states, but also regarding intentions, personality, and complex social characteristics. The present research investigates how a smiling, compared to a nonsmiling, expression impacts decision making and underlying cognitive and emotional processes in economic bargaining. Our results using the ultimatum game show that facial expressions have an impact on decision making as well as the feedback-related negativity following the offer. Furthermore, a moderating effect of sex on decision making was observed, with differential effects of facial expressions from male compared to female proposers. It is concluded that predictions of bargaining behavior must account for aspects of social interactions as well as sex effects to obtain more precise estimates of behavior., (Copyright © 2014 Society for Psychophysiological Research.)

The feedback-related negativity (FRN) is thought to index activity within the midbrain dopaminergic reward-learning system, with larger FRN magnitudes observed when outcomes are worse than expected. This view holds that the FRN is an index of neural activity coding for prediction errors, and reflects activity that can be used to adaptively alter future performance. Untested to date, however, is a key prediction of this view: the FRN should not appear in response to negative outcomes when outcome expectations are not allowed to develop. The current study tests this assumption by eliciting FRNs to win and loss feedback in conditions of participant choice, participant observation of computer choice, and, critically, simple presentation of win or loss feedback in the absence of a predictive choice cue. Whereas FRNs were observed in each of the conditions in which there was time for an expectation to develop, no FRN was observed in conditions without sufficient time for the development of an expectation. These results provide empirical support for an untested but central tenet of the reinforcement learning account of the genesis of the FRN., (Copyright © 2012 Society for Psychophysiological Research.)

We present evidence that a multitude of mid-frontal event-related potential (ERP) components partially reflect a common theta band oscillatory process. Specifically, mid-frontal ERP components in the N2 time range and error-related negativity time range are parsimoniously characterized as reflections of theta band activities. Forty participants completed three different tasks with varying stimulus-response demands. Permutation tests were used to identify the dominant time-frequency responses of stimulus- and response-locked conditions as well as the enhanced responses to novelty, conflict, punishment, and error. A dominant theta band feature was found in all conditions, and both ERP component amplitudes and theta power measures were similarly modulated by novelty, conflict, punishment, and error. The findings support the hypothesis that generic and reactive medial prefrontal cortex processes are parsimoniously reflected by theta band activities., (Copyright © 2011 Society for Psychophysiological Research.)

Relatively less right parietal activity may reflect reduced arousal and signify risk for major depressive disorder (MDD). Inconsistent findings with parietal electroencephalographic (EEG) asymmetry, however, suggest issues such as anxiety comorbidity and sex differences have yet to be resolved. Resting parietal EEG asymmetry was assessed in 306 individuals (31% male) with (n=143) and without (n=163) a DSM-IV diagnosis of lifetime MDD and no comorbid anxiety disorders. Past MDD+ women displayed relatively less right parietal activity than current MDD+ and MDD- women, replicating prior work. Recent caffeine intake, an index of arousal, moderated the relationship between depression and EEG asymmetry for women and men. Findings suggest that sex differences and arousal should be examined in studies of depression and regional brain activity., (Copyright © 2010 Society for Psychophysiological Research.)

Frontal alpha asymmetry is typically computed using alpha power averaged across many overlapping epochs. Previous reports have estimated the internal consistency reliability of asymmetry by dividing resting EEG sessions into segments of equal duration (e.g., 1 min) and treating asymmetry scores for each segment as "items" to estimate internal consistency reliability using Cronbach's alpha. Cronbach's alpha partly depends on the number of items, such that this approach may underestimate reliability by using less than the number of distinct items available. Reliability estimates for resting EEG data in the present study (204 subjects, 8 sessions) were obtained using mean split-half correlations with epoch alpha power as treated as separate items. Estimates at all scalp sites and reference schemes approached .90 with as few as 100 epochs, suggesting the internal consistency of frontal asymmetry is greater than that previously reported.

Few data are available to address whether the use of ERP-based deception detection alternatives have sufficient validity for applied use. The present study was designed to replicate and extend J. P. Rosenfeld, M. Soskins, G. Bosh, and A. Ryan's (2004) study by utilizing a virtual reality crime scenario to determine whether ERP-based procedures, including brain fingerprinting, can be rendered less effective by participant manipulation by employing a virtual reality crime scenario and multiple countermeasures. Bayesian and bootstrapping analytic approaches were used to classify individuals as guilty or innocent. Guilty subjects were detected significantly less frequently compared to previous studies; countermeasures further reduced the overall hit rates. Innocent participants remained protected from being falsely accused. Reaction times did not prove suitable for accurate classification. Results suggested that guilty verdicts from ERP-based deception detection approaches are likely to be accurate, but that innocent (or indeterminate) verdicts yield no useful interpretation in an applied setting.

Although resting frontal electroencephalographic (EEG) alpha asymmetry has been shown to be a stable measure over time in nonclinical populations, its reliability and stability in clinically depressed individuals has not been fully investigated. The internal consistency and test-retest stability of resting EEG alpha (8-13 Hz) asymmetry were examined in 30 women diagnosed with major depression at 4-week intervals for 8 or 16 weeks. Asymmetry scores generally displayed good internal consistency and exhibited modest stability over the 8- and 16-week assessment intervals. Changes in asymmetry scores over this interval were not significantly related to changes in clinical state. These findings suggest that resting EEG alpha asymmetry can be reliably assessed in clinically depressed populations. Furthermore, intraclass correlation stability estimates suggest that although some traitlike aspects of alpha asymmetry exist in depressed individuals, there is also evidence of changes in asymmetry across assessment occasions that are not closely linked to changes in depressive severity.

Two studies have examined whether there exists a relationship between resting frontal alpha asymmetry and the Behavioral Inhibition and Activation Scales (C. S. Carver & T. L. White, 1994), which are based on Gray's Behavioral Inhibition and Behavioral Activation Systems. Findings suggest that greater relative left frontal activity characterizes individuals higher in self-reported behavioral activation sensitivity (E. Harmon-Jones & J. J. B. Allen, 1997; S. K. Sutton & R. J. Davidson, 1997), and, in one instance, lower behavioral inhibition sensitivity (S. K. Sutton & R. J. Davidson, 1997). In the present study, relatively greater left frontal activity correlated positively with behavioral activation scores. No significant relationship between resting frontal alpha asymmetry and the behavioral inhibition score emerged. These data suggest that relatively greater left frontal activity is indeed an index of approach oriented, appetitive motivational tendencies, whereas the relationship between relative right frontal activity and the behavioral inhibition system is likely to be complex and not accounted for by behavioral withdrawal alone.

Increased vagal tone has been associated with treatment success using pharmacological agents and cognitive-behavioral treatment in major depression, but not using electroconvulsive therapy. The present study investigated whether increases in vagal tone would be associated with favorable treatment response with nonpharmacological treatment. At baseline and following treatment, 16 subjects were administered the Hamilton Rating Scale for Depression (HRSD) followed by electrocardiographic recording. Those with little change in vagal tone from before to after treatment showed minimal reduction in HRSD score (-4.8); those with larger vagal tone change showed a large decrease in HRSD score (-14.8). Changes in vagal tone are thus related to favorable treatment response in depression, and do not represent anticholinergic pharmacological effects. Future work manipulating vagal tone might prove informative in teasing apart the causal role of vagal tone and depression.

Psychophysiological measures hold great potential for informing clinical assessments. The challenge, before such measures can be widely used, is to develop test procedures and analysis strategies that allow for statistically reliable and valid decisions to be made for any particular examinee, despite large individual differences in psychophysiological responding. Focusing on the evaluation of memory in clinical, criminal, and experimental contexts, this paper reviews the rationale for and development of ERP-based memory assessment procedures, with a focus on methods that allow for statistically supported decisions to be made in the case of a single examinee. The application of one such procedure to the study of amnesia in Dissociative Identity Disorder is highlighted. To facilitate the development of other psychophysiological assessment tools, psychophysiological researchers are encouraged to report the sensitivity and specificity of their measures where possible.

Brain activity was monitored while 36 participants produced facial configurations denoting anger, disgust, fear, joy, and sadness. EEG alpha power was analyzed during each facial pose, with facial conditions grouped according to the approach/withdrawal motivational model of emotion. This model suggests that "approach" emotions are associated with relatively greater left frontal brain activity whereas "withdrawal" emotions are associated with relatively greater right frontal brain activity. In the context of a bilateral decrease in activation, facial poses of emotions in the withdrawal condition resulted in relatively less left frontal activation in the lateral-frontal, midfrontal and frontal-temporal-central region, but not in the parietal region, as predicted. Findings in the approach condition were less consistently supportive of predictions of the approach/withdrawal model. Implications for the approach/withdrawal model and for the emotion eliciting potential of voluntary facial movement are discussed.

Individual differences in resting asymmetrical frontal brain activity have been found to predict subsequent emotional responses. The question of whether frontal brain asymmetry can cause emotional responses has yet to be addressed. Biofeedback training designed to alter the asymmetry of frontal brain activity was therefore examined. Eighteen right-handed female participants were randomly assigned to receive biofeedback training designed to increase right frontal alpha relative to left frontal alpha (n = 9) or to receive training in the opposite direction (n = 9). Five consecutive days of biofeedback training provided signals of reward or nonreward depending on whether the difference between right (F4) and left (F3) frontal alpha exceeded a criterion value in the specified direction. Systematic alterations of frontal EEG asymmetry were observed as a function of biofeedback training. Moreover, subsequent self-reported affect and facial muscle activity in response to emotionally evocative film clips were influenced by the direction of biofeedback training.

The present study used the picture perception paradigm to examine the extent to which three well-documented psychophysiological measures demonstrate consistency across time in response to emotional stimuli. The three measures were the eye-blink startle response and the activation in two facial muscle regions (zygomatic and corrugator). Twenty-seven young women were assessed on two occasions, 2 weeks apart. Whereas activation in the corrugator and zygomatic muscle regions demonstrated the predicted patterns at both assessments (with some attenuation in the zygomatic muscle regions), the startle response had limited consistency across the two assessments. The startle response revealed the predicted linear pattern of valence modulation during the first assessment. During the second assessment, startle magnitude response was a quadratic function of valence ratings and a linear function of arousal ratings. The unexpected pattern of startle response during the second session appeared to be related to the content of the pleasant slides, with action slides generating quadratic valence modulation and erotic slides continuing to exhibit the expected linear valence modulation.

The error-related negativity (ERN) is a response-locked brain potential generated when individuals make mistakes during simple decision-making tasks. In the present study, we examined ERN under conditions of reward and punishment, among participants who scored extremely low or high on the socialization scale of the California Psychological Inventory (CPI). Participants completed a forced-choice task, and were rewarded for correct responses in half the trials, and punished for incorrect responses in the remaining trials. A significant interaction between socialization (SO) and condition revealed that low-SO participants produced smaller ERNs during the punishment task than during the reward task, whereas high-SO participants produced similar ERNs in both conditions. Reaction time and electromyogram data essentially bolster the interpretation that the ERN effects reflect differences in error salience for high-SO and low-SO participants, and are consistent with the avoidance-learning deficits seen in psychopathy.

Two studies of the relationship between depression and resting frontal electroencephalographic (EEG) activity are reported. Although considerable research supports the theory of left and right hemispheric specialization for approach and withdrawal behaviors, only four studies involving clinically depressed individuals have been published to date. Despite methodological similarities with published research, no significant differences in frontal activation emerged between depressed and nondepressed participants with either college students having high Beck Depression Inventory scores (Study 1) or with individuals diagnosed with DSM-III-R depression (Study 2). Post hoc analyses in Study 2 revealed one effect confined to lateral frontal leads during the first 2 min of EEG data; this finding was significant in only one of three reference montages. Results are discussed in light of methodological considerations and mediating variables such as temperament and coping styles.

We previously reported that a Bayesian-based event-related potential memory assessment procedure (Allen, Iacono, & Danielson, 1992, Psychophysiology, 29, 504-522) was highly accurate at identifying previously learned material, regardless of an individual's motivational incentive to conceal information. When a bootstrapping procedure (Farwell & Donchin, 1991, Psychophysiology, 28, 531-547) is applied to these same data, greater motivational incentives appear to increase the accuracy of the procedure. Receiver operating characteristic (ROC) curves were used to examine these two procedures and a new procedure. ROC curves indicated that all three methods produce extremely high rates of classification accuracy and that the sensitivity of the bootstrapping procedure to motivational incentive is due to the particular cut points selected. One or the other method may be preferred depending upon incentive to deceive, the cost of incorrect decisions, and the availability of extra psychophysiological data.

The development and validation of an event-related potential (ERP) memory assessment procedure is detailed. The procedure identifies learned material with high rates of accuracy, whether or not subjects give intentional responses indicating they had previously learned it. Because the traditional analysis of variance approach fails to provide probabilistic conclusions about any given individual, Bayesian posterior probabilities were computed, indicating the probability for each and every person that material was learned. The method was developed on a sample of 20 subjects, and then cross-validated on two additional samples of 20 subjects each. Across the three samples, the method correctly defined over 94% of learned material as learned, and misclassified 4% of the unlearned material. Additionally, in a simple oddball task performed by the same subjects, the method classified rare and frequent material with perfect accuracy. Finally, combining two implicit behavioral measures--mean reaction time and the number of incorrect responses--in Bayesian fashion yielded classification accuracy that actually exceeded that of the ERP-based procedure overall, but the two methods provided identical accuracy in classifying the most critical material as recognized.