Jeffrey B. Henriques

Left Frontal Hypoactivation in Depression

Baseline resting electroencephalogram activity was recorded with 3 different reference montages from 15 clinically depressed and 13 control subjects. Power in all frequency bands was extracted by fast Fourier transformation. There was a significant Group X Hemisphere interaction in the mid-frontal region, for the alpha band power only. Depressed subjects had less left-sided activation (i.e., more alpha activity) than did normal control subjects. This pattern of diminished left-sided frontal activation is interpreted as indicating a deficit in approach mechanisms in depressed subjects.

Resting Frontal Brain Asymmetry Predicts Affective Responses to Films

This article assessed whether resting electroencephalographic (EEG) asymmetry in anterior regions of the brain can predict affective responses to emotion elicitors. Baseline EEG was recorded from 32 female adults, after which Ss viewed film clips preselected to elicit positive or negative affect. Resting alpha power asymmetry in the frontal region significantly predicted self-reported global negative affect in response to clips and predicted the difference between global positive and negative affect. Analyses of discrete emotions revealed a strong relation between frontal asymmetry and fear responses to films. Effects were independent of Ss mood ratings at the time at which baseline EEG was measured. Resting anterior asymmetry may be a state-independent index of the individuals predisposition to respond affectively.

While a phobic waits: regional brain electrical and autonomic activity in social phobics during anticipation of public speaking

BACKGROUND Recent studies have highlighted the role of right-sided anterior temporal and prefrontal activation during anxiety, yet no study has been performed with social phobics that assesses regional brain and autonomic function. This study compared electroencephalograms (EEGs) and autonomic activity in social phobics and controls while they anticipated making a public speech. METHODS Electroencephalograms from 14 scalp locations, heart rate, and blood pressure were recorded while 18 DSM-IV social phobics and 10 controls anticipated making a public speech, as well as immediately after the speech was made. Self-reports of anxiety and affect were also obtained. RESULTS Phobics showed a significantly greater increase in anxiety and negative affect during the anticipation condition compared with controls. Heart rate was elevated in the phobics relative to the controls in most conditions. Phobics showed a marked increase in right-sided activation in the anterior temporal and lateral prefrontal scalp regions. These heart rate and EEG changes together accounted for > 48% of the variance in the increase in negative affect during the anticipation phase. CONCLUSIONS These findings support the hypothesis of right-sided anterior cortical activation during anxiety and indicate that the combination of EEG and heart rate changes during anticipation account for substantial variance in reported negative affect.

Decreased responsiveness to reward in depression

We have interpreted the literature showing left anterior hypoactivation in depression as reflecting a decrease in approach-related motivation and behaviour among depressed subjects. In support of this model, we have previously demonstrated a decreased responsiveness to reward in subclinically depressed dysphoric subjects. The current study was designed to replicate and extend those findings. Clinically depressed subjects who met DSM-IV criteria for major depression were compared to a group of nondepressed control subjects on a verbal memory task under three monetary payoff conditions: neutral, reward, and punishment. Although control subjects changed their pattern of responding in both the reward and punishment conditions, relative to the neutral condition, so as to maximise their earnings, depressed subjects did not do so during reward. The two groups did not differ during the punishment condition. These findings provide additional evidence of a decreased responsiveness to reward in depressed individuals, and are consistent with the hypothesis that the left prefrontal hypoactivation observed in depression reflects a deficit in approach-related behaviour.

Frontal Brain Asymmetry and Reward Responsiveness A Source-Localization Study

The influence of approach and avoidance tendencies on affect, reasoning, and behavior has attracted substantial interest from researchers across various areas of psychology. Currently, frontal electroencephalographic (EEG) asymmetry in favor of left prefrontal regions is assumed to reflect the propensity to respond with approach-related tendencies. To test this hypothesis, we recorded resting EEG in 18 subjects, who separately performed a verbal memory task under three incentive conditions (neutral, reward, and punishment). Using a source-localization technique, we found that higher task-independent alpha2 (10.5–12 Hz) activity within left dorsolateral prefrontal and medial orbitofrontal regions was associated with stronger bias to respond to reward-related cues. Left prefrontal resting activity accounted for 54.8% of the variance in reward bias. These findings not only confirm that frontal EEG asymmetry modulates the propensity to engage in appetitively motivated behavior, but also provide anatomical details about the underlying brain systems.

Reward fails to alter response bias in depression.

Several different models postulate that depression is associated with decreased approach-related behavior. Relatively little has been done to date to specifically investigate this issue. In the present study, a signal-detection analysis was used to examine the response biases of dysphoric and nondysphoric female undergraduates during 3 payoff conditions: neutral, reward, and punishment. As predicted, the dysphoric subjects had a smaller change in bias from the neutral to the reward condition compared with the nondysphoric group. The 2 groups did not differ during the neutral and punishment conditions. These findings are consistent with the hypothesis that the left frontal hypoactivation observed in depression reflects a deficit in approach-related behavior.

Support for the Reliability and Validity of a Six-Item State Anxiety Scale Derived From the State-Trait Anxiety Inventory

Identifying the most efficient and theoretically appropriate methods to assess patient anxiety in fast-paced medical environments may be beneficial for clinical purposes as well as for research. The purpose of this study was to examine the reliability and validity of two previously published six-item versions of the State form of the State-Trait Anxiety Inventory (STAI) and to identify the version that would be most appropriate to use with a sample of parents who had infants with normal or abnormal newborn screens. In the current study, confirmatory factor analyses were conducted to evaluate the fit of the two six-item forms with STAI data collected at three time points from 288 parents of 150 infants. Study groups of parents were based upon infant newborn screens and subsequent diagnostic testing to include cystic fibrosis (CF; n = 26), congenital hypothyroidism (CH; n = 39), CF Carriers (CF–C; n = 45), and healthy infants (H; n = 40). The results showed the version containing items 1, 3, 6, 15, 16, and 17 of the State form of the STAI to be a better fitting model across all three time points, and it had better internal consistency than the version containing items 5, 9, 10, 12, 17, and 20. Both short forms were highly correlated with the 20-item STAI score, and all internal consistency reliabilities were greater than .90. It was concluded that the version containing items 1, 3, 6, 15, 16, and 17 of the State Anxiety scale was a reliable and valid instrument for this study sample.

Brain electrical asymmetries during cognitive task performance in depressed and nondepressed subjects

BACKGROUND Studies using electroencephalogram (EEG) measures of activation asymmetry have reported differences in anterior asymmetry between depressed and nondepressed subjects. Several studies have suggested reciprocal relations between measures of anterior and posterior activation asymmetries. We hypothesized that depressed subjects would fail to show the normal activation of posterior right hemisphere regions in response to an appropriate cognitive challenge. METHODS EEG activity was recorded from 11 depressed and 19 nondepressed subjects during the performance of psychometrically matched verbal (word finding) and spatial (dot localization) tasks. Band power was extracted from all epochs of artifact-free data and averaged within each condition. Task performance was also assessed. RESULTS Depressed subjects showed a specific deficit in the performance of the spatial task, whereas no group differences were evident on verbal performance. In posterior scalp regions, nondepressed controls had a pattern of relative left-sided activation during the verbal task and relative right-sided activation during the spatial task. In contrast, depressed subjects failed to show activation in posterior right hemisphere regions during spatial task performance. CONCLUSIONS These findings suggest that deficits in right posterior functioning underlie the observed impairments in spatial functioning among depressed subjects.

Psychosocial Variables, External Barriers, and Stage of Mammography Adoption

Guided by H. Triandiss (1980) theory of behavior and the transtheoretical model, the study purpose was to examine differences in psychosocial variables and external conditions by stage of mammography adoption. Sampled from a statewide population, participants (N=509) were women aged 51-80. They had been contacted by telephone, screened for eligibility (e.g., no history of cancer or recent mammogram), and interviewed 3-6 months later. Higher utility beliefs, social influences, and practitioner interactions about mammography were associated with improved stage of adoption, as were lower negative affect and external barriers regarding mammography. Higher decisional balance scores, with and without negative affect toward mammography were associated with improved stage. Controlling for variables reflecting pros and cons, negative affect toward mammography further distinguished among stages. A richer set of pros and cons measures could explain screening more fully.

The Effect of Graphics on Environmental Health Risk Beliefs, Emotions, Behavioral Intentions, and Recall

Lay people have difficulty understanding the meaning of environmental health risk information. Visual images can use features that leverage visual perception capabilities and semiotic conventions to promote meaningful comprehension. Such evidence-based features were employed to develop two images of a color-coded visual scale to convey drinking water test results. The effect of these images and a typical alphanumeric (AN) lab report were explored in a repeated measures randomized trial among 261 undergraduates. Outcome measures included risk beliefs, emotions, personal safety threshold, mitigation intentions, the durability of beliefs and intentions over time, and test result recall. The plain image conveyed the strongest risk message overall, likely due to increased visual salience. The more detailed graded image conveyed a stronger message than the AN format only for females. Images only prompted meaningful risk reduction intentions among participants with optimistically biased safety threshold beliefs. Fuzzy trace theory supported some findings as follow. Images appeared to promote the consolidation of beliefs over time from an initial meaning of safety to an integrated meaning of safety and health risk; emotion potentially shaped this process. Although the AN report fostered more accurate recall, images were related to more appropriate beliefs and intentions at both time points. Findings hinted at the potential for images to prompt appropriate beliefs independent of accurate factual knowledge. Overall, results indicate that images facilitated meaningful comprehension of environmental health risk information and suggest foci for further research.