Anticipatory Skin Conductance Research Articles

Relationships between affective states and decision-making

The study investigated relationships between affective states and decision-making performance using the Iowa Gambling Task. Playing the task involves making decisions between four card decks. Two decks yield high gains and high losses, and if chosen continuously these decks lead to net loss. In contrast, the other two decks yield small gains and small losses, but lead to net profit if they are selected continuously. Correlation and regression analyses revealed a positive relationship between trait-anxiety and decision-making performance and a negative relationship between self-reported emotion regulation and decision-making performance. In addition, anticipatory skin conductance responses were related positively to trait-anxiety and negatively to self-reported emotion regulation. These findings support the somatic marker hypothesis suggesting that emotions facilitate decision-making in complex situations that have uncertain future outcomes.

Anticipation of cognitive demand during decision-making

An abundance of evidence indicates that action selection is guided, at least in certain contexts, by anticipation of action outcomes. In one particularly clear demonstration of this principle, Bechara and colleagues, studying a gambling task, observed phasic skin conductance responses just prior to actions associated with a relatively high risk of monetary loss (Bechara et al. in J Neurosci 19:5473-5481, 1999; Bechara et al. in Science 275:1293-1295, 1997; Bechara et al. in Cereb Cortex 6:215-225, 1996). In the present work, we tested for the same effect in a paradigm where choices resulted not in differential monetary outcomes, but in differential requirements for subsequent mental effort. In two experiments, we observed an anticipatory skin conductance response prior to actions resulting in a high level of cognitive demand. This finding indicates that requirements for effortful cognitive control are anticipated during action selection. We argue, based on convergent evidence, that such anticipation may not only trigger preparation; it may also play a direct role in effort-based decision-making.

The Effect of Rewards and Punishment on Affective Decision-Making in Children-with Two Subtypes of ADHD

Although most of the theories on attention deficit hyperactivity disorder (ADHD) assumed that deficit in behavioral inhibition was probably the core problem of ADHD, recent studies implied that ADHD patients have aberrant sensitivity to reinforcement, such as rewards and punishment (Sergeant J et al.2000, 2005; Luman M et al. 2005), or emotional control deficit. This aberrant sensibility hypothesis challenges the traditional view on ADHD. However, whether the patients are aberrant sensitive to rewards or to punishment are not clear. Moreover, some relevant studies indicated that Skin conductance responses could reflect their physical arousal while subject responding to cognitive, emotional and social stimulus (Fishbein D et al.2005). Using two experimental designs, the present study examined the effect of rewards and punishment on affective decision-making on two subtypes of children with attention deficit hyperactivity disorder (ADHD) and normal controls, and recorded their anticipatory Skin conductance recordings (SCRs) as well. Thirty-eight children between 7 and 12 years old with a clinical diagnosis of ADHD (22 of predominantly inattentive, i.e., ADHD-I; and 16 of combined, i.e., ADHD-C) were compared to 38 normal controls who were matched in age, IQ and the year of education in affective decision-making. Two variations of the Iowa Gambling Task (Bechara et al, 2000) were used, which typically involved two sets of cards in computer. On each of 100 trails, children chose from 1of 2 decks of cards, when turned, which displayed happy and sad faces (experiment 1), or red and green star (experiment 2) corresponding to rewards or punishment respectively, that means won (happy face or red star) or lost (sad face or green star) cartoon cards by each choice. Cards in 1 deck offered more rewards per trail, but were disadvantageous across trails due to occasional large losses; cards in the other deck offered fewer rewards per trial, but were advantageous overall. Different from the previous studies, the intension of rewards and punishment was manipulated in this study. The results showed that ADHD children were impaired in affective decision-making, and generated lower anticipatory SCRs during the later part of task before choosing from disadvantage card compared with normal controls at the conditions of instant rewards, but were intact at the condition of instant punishment. No significant differences were observed between the two subtypes of ADHD. The results of which suggested that the children with the two subtypes of ADHD only have aberrant sensibility to rewards, therefore impaired their decision-making. However, they showed the same pattern with normal children when avoiding punishment.

Is aversive learning a marker of risk for anxiety disorders in children?

Aversive conditioning and extinction were evaluated in children with anxiety disorders ( n=23), at-risk for anxiety disorders ( n=15), and controls ( n=11). Participants underwent 16 trials of discriminative conditioning of two geometric figures, with (CS+) or without (CS−) an aversive tone (US), followed by 8 extinction trials (4 CS+, 4 CS−), and 8 extinction re-test trials averaging 2 weeks later. Skin conductance responses and verbal ratings of valence and arousal to the CS+/CS− stimuli were measured. Anxiety disordered children showed larger anticipatory and unconditional skin conductance responses across conditioning, and larger orienting and anticipatory skin conductance responses across extinction and extinction re-test, all to the CS+ and CS−, relative to controls. At-risk children showed larger unconditional responses during conditioning, larger orienting responses during the first block of extinction, and larger anticipatory responses during extinction re-test, all to the CS+ and CS−, relative to controls. Also, anxiety disordered children rated the CS+ as more unpleasant than the other groups. Elevated skin conductance responses to signals of threat (CS+) and signals of safety (CS−; CS+ during extinction) are discussed as features of manifestation of and risk for anxiety in children, compared to the specificity of valence judgments to the manifestation of anxiety.

Affective biasing of choices in gambling task decision making

The proponents of the somatic marker hypothesis presume that rational decision making is guided by emotional reactions that are developed from prior experience. Supporting evidence for the hypothesis comes almost exclusively from the short-term affective reactions that are learned during the course of a hypothetical decision-making task--the gambling task (GT). We examined GT performance and affective reactions to choices when those choices were biased by words that had preexisting affective value. In one experiment, affectively valued words directly signaled good and bad choices. A congruent relation between affective value of word and choice outcome improved GT performance, whereas an incongruent relation greatly interfered with performance. In another experiment, affectively valued words were maintained as a working memory (WM) load between GT choices. A WM load with affectively positive words somewhat improved GT performance, whereas affectively negative words interfered with performance. Somatic markers-indicated by differential anticipatory skin conductance response (SCR) amplitude for good and bad choices-appeared at a point in the GT session when choice performance was superior. However, differential SCR developed during the session after good choice performance was already established. These results indicate that preexisting affective biases can influence GT decision making. In addition, the somatic markers that are regular accompaniments of GT decision making appeared to be temporally lagging indicators of choice performance.

Psychophysiological anticipation of positive outcomes promotes advantageous decision-making in normal older persons

Previous studies have demonstrated that aging has an adverse effect on laboratory decision-making in some older adults, and such findings have important implications for real-world reasoning and judgment. Emotion, and its accompanying somatic responses, is thought to contribute significantly to decision-making. In the present study, we had two objectives: 1) to investigate decision-making in a new sample of elderly participants, using the Iowa Gambling Task (IGT); and 2) to investigate psychophysiological correlates of decision-making, focusing on anticipatory skin conductance responses (SCRs) that participants produce immediately prior to their behavioral response. We hypothesized that the previous behavioral findings would be replicated, and further, that the older adult participants with IGT impairments would show a lack of discriminatory anticipatory SCRs during the IGT. The results supported both predictions. First, a subgroup of the new elderly sample demonstrated impaired decision-making on the IGT, replicating our previous findings. Second, the participants with impaired IGT performance failed to demonstrate discriminatory anticipatory SCRs for advantageous versus disadvantageous choices, whereas participants with normal IGT performance did demonstrate such discrimination; in the latter case, however, SCR magnitude was higher for advantageous decisions (unlike the pattern in young normal adults). Our data lead to the suggestion that strong decision-making abilities among older adults may be a function of positive somatic markers, whereas poor decision-making abilities may arise from an abnormal somatic response generated in anticipation of a future event.

May et al.'s "Anomalous Anticipatory Skin Conductance Response to Acoustic Stimuli"

May et al.'s "Anomalous Anticipatory Skin Conductance Response to Acoustic Stimuli"

Anomalous Anticipatory Skin Conductance Response to Acoustic Stimuli: Experimental Results and Speculation About a Mechanism

The primary aim of this study was to conduct a replication, simplification, and extension of similar previous studies that claimed anomalous anticipatory skin conductance responses prior to various stimuli and to provide sufficient protocol and analysis details in order to foster additional replications. A secondary aim was to provide a testable model in order to understand the observed results. We used standard skin conductance measures and techniques to search within 50 participants for responses prior to 1-second duration, 97-dB acoustic stimuli, compared to prior to silent controls. We used an interstimulus interval randomly and uniformly distributed between 30 and 50 seconds. The dependent variable was the difference between proportions of 3.5-second prestimulus intervals prior to acoustic stimuli and prior to silent controls that contained a fully formed, nonspecific skin conductance response (ns-SCR). The null hypothesis was that the proportion difference should be zero. We found a significant proportion difference of 0.032 (Z = 2.08; effect size = 0.077 +/- 0.037; p(1t) = 0.0018), which is a replication of earlier similar studies. We examined and ruled out a number of potential artifacts that might have accounted for this finding. To understand these results, we demonstrated, by Monte Carlo techniques, that a possible explanation is that experimenters may have used their own intuition to initiate experiment runs to somehow sort otherwise random nonspecific skin conductance responses into appropriate bins in order to mimic physiological responses. We found experimental evidence to support this idea as an operational mechanism. If this speculation is confirmed in prospective studies, then this intuition-based mimicking of effects may profoundly impact the interpretation of results from complementary and alternative medical studies that use statistical inference to assess outcomes.

Reduced Electrodermal Activity in Psychopathy-Prone Adolescents.

This study tests the hypothesis that psychopathy-prone adolescents show reduced anticipatory skin conductance responding. Electrodermal activity was recorded while participants anticipated and responded to a 105 dB signaled or unsignaled white-noise burst. Using an extreme groups design, the authors used Child Psychopathy Scale (D. R. Lynam, 1997) scores from a community sample of 335 male adolescents (age 16) to form control (n = 65) and psychopathy-prone (n = 65) groups. Significantly more psychopathy-prone participants were nonresponders in the signaled anticipatory (p = .014), signaled responsivity (p = .037), and unsignaled responsivity (p = .003) conditions compared with controls. Anticipatory hyporesponsivity of psychopathy-prone adolescents similar to the electrodermal hyporesponsivity found in psychopathic adults suggests that this autonomic impairment is present by adolescence and may predispose individuals to adult psychopathy.

Asymmetric Functional Roles of Right and Left Ventromedial Prefrontal Cortices in Social Conduct, Decision-Making, and Emotional Processing

The aim of this study was to begin to parse the relative contributions of the right and left ventromedial prefrontal cortices (VMPC) in regard to social conduct, decision-making, and emotional processing. We hypothesized that the right VMPC is a critical component of the neural systems that subserve such functions, whereas the left VMPC is not. Seven participants with focal, stable unilateral lesions to the right (n = 4) or left (n = 3) VMPC were studied with procedures designed to measure social conduct, decision-making, and emotional processing and personality. The right-sided participants had profound disturbances of social and interpersonal behavior and of the ability to maintain gainful employment; they had defective performance and impaired anticipatory skin conductance responses during the Gambling Task; most had profound abnormalities of emotional processing and personality, and met criteria for “acquired sociopathy.” By contrast, the left-sided participants had normal social and interpersonal behavior; they had stable employment; they performed normally and had normal skin conductance responses on the Gambling Task; they had normal emotional processing; and their personalities were unchanged from premorbid status. The marked deficits in social conduct, decision-making, and emotional processing in participants with unilateral right VMPC lesions are reminiscent in kind of those that have been reported in connection with bilateral VMPC lesions, albeit perhaps of lesser severity. The findings provide preliminary evidence that insofar as social, decision-making, and emotional functions are concerned, the right-sided component of the VMPC system may be critical, whereas the left-sided component may be less important.