The aim of this research was to study the influence of both the emotional content and the physical characteristics of affective stimuli on the psychophysiological, behavioral and cognitive indexes of the emotional response. We selected 54 pictures from the IAPS, depicting unpleasant, neutral, and pleasant contents, and used two picture sizes as experimental conditions (120 × 90 cm and 52 × 42 cm). Sixty-one subjects were randomly assigned to each experimental condition. We recorded the startle blink reflex, skin conductance response, heart rate, free viewing time, and picture valence and arousal ratings. In line with previous research (e.g., Bradley, Codispoti, Cuthbert, & Lang, 2001), our data showed an effect of the affective content on all the measurements recorded. Importantly, effects of the size of the affective pictures on emotional responses were not found, indicating that the emotional content is more important than the formal properties of the stimuli in evoking the emotional response.

Two human Pavlovian conditioning experiments investigated the impact of reinforcement density (the number of reinforced trials divided by the total number of trials) on discrimination learning. Experiment 1 used a negative patterning problem (A+, B+, AB−) and Experiment 2 used a positive patterning problem (A−, B−, AB+). In both experiments, reinforcement density varied across four levels. Response differentiation between reinforced and nonreinforced stimuli was linearly related to the decrease in reinforcement density. Responses to nonreinforced stimuli did not differ between the four groups in either experiment. In contrast to this, responses to reinforced stimuli were considerably more pronounced in conditions with lower reinforcement density. For negative patterning, this replicates and extends similar observations from other species. For positive patterning, this is a finding that has not yet been reported in other experiments. The results are in agreement with the comparator hypothesis (Miller & Matzel, 1988) and with Wagner's (1981) “standard operating procedures” (SOP) model.

Two dimensions of narcissism were related to psychophysiological responses to stress in 50 young women. Cardiovascular, electrodermal, task performance, and stress appraisal measures were recorded during rest, mental arithmetic, and a computerized Thematic Apperception Test (Murray, 1943). The Egocentricity and Alienation scales of the Bell Object Relations and Reality Testing Inventory (Bell, 1995) served as measures of overt/inflated and covert/deflated narcissism. Egocentricity correlated consistently with heightened preejection period reactivity, whereas Alienation correlated consistently with diminished electrodermal reactivity (all p < .05). Multivariate analyses supported specific relationships between Egocentricity and preejection period hyperreactivity, and between Alienation and electrodermal hyporeactivity. These results have implications for narcissism, cardiovascular disease risk, and a variety of psychiatric disorders.

There is growing evidence that in human skin conductance response (SCR) conditioning positive patterning (A−, B−, AB+) and negative patterning (A+, B+, AB−) are solved by applying two different rules. The present experiments investigated whether the representations of such rules are specific or general with regard to outcomes and response systems. In Experiment 1, we investigated SCR and eyelid conditioning with different types of training administered in an interleaved fashion. We found that positive patterning SCR conditioning interfered with negative patterning SCR conditioning, whereas eyeblink conditioning had no effect on SCR conditioning. In Experiment 2, in which eyeblink and SCR conditioning were administered in sequential fashion, the same result was obtained. We conclude that the rules involved in solving patterning tasks might be specific to outcomes and/or response systems.

This study provides the first psychophysiological analysis of narcissism by measuring autonomic responses during active and passive anticipatory coping in 40 undergraduate men who scored high or low on the Narcissistic Personality Inventory (NPI). Compared to the low NPI group, the high NPI group showed greater preejection period (PEP) shortening, cardiac deceleration, and skin conductance response (SCR) habituation during anticipation of an aversive stimulus (p < .02). As expected, SCR and PEP reactivity were greater during active than passive coping. In the case of PEP, this effect emerged only in the low NPI group; the high NPI group showed the greatest PEP reactivity during the first task, regardless of coping demands. These data support hypothesized relationships among narcissism, psychopathy, and psychological predictors of cardiovascular disease, and suggest that a psychobiological dimension may underlie important features of narcissism.

Results obtained with the standard repetition-change paradigm of orienting research cannot be attributed unambiguously to either stimulus change or to unexpectedness. By adding announcement conditions, in which participants were told about an impending stimulus change, these two factors were disentangled. In Experiment 1, reaction times (RTs) were longer and ratings of surprise were higher with unannounced than with announced stimulus change. In contrast, larger skin conductance response (SCR) magnitudes occurred following change, irrespective of its congruence with participants' expectations. Experiment 2 replicated the results for SCR magnitude and, furthermore, revealed the same pattern of results for the evoked cardiac response. Surprise ratings again reflected the unexpectedness of stimulus presentations. The dissociation between RT and autonomic measures provides difficulties for resource allocation accounts of the orienting response.

The prediction that orienting response (OR) reinstatement is negatively related to the measure of common features, shared by the stimulus input and representations of preceding events, and positively related to the measure of their distinctive features, was examined. A nonsignificant test stimulus (TS) was presented after nine repetitions of a standard stimulus (SS), followed by two additional repetitions of SS. TS was created by either substituting 0, 1, or 2 components of SS (Experiment 1), or by either adding or deleting 0, 1, or 2 components of SS (Experiment 2). Skin conductance changes to TS (OR reinstatement) and the subsequent SS (dishabituation) were used as dependent measures. The results of Experiment 1 supported the prediction that substituting components of neutral stimuli affects OR reinstatement, with a larger effect for between-categories than within-categories substitution. Experiment 2 demonstrated that adding and deleting components similarly affects OR reinstatement.

To reveal areas in the central nervous system of importance for electrodermal control, regional cerebral blood flow (rCBF) was correlated to nonspecific skin conductance fluctuations (NSF) during aversive and nonaversive conditions. Participants viewed a TV screen displaying white noise or snake videotapes presented both with and without electric shocks given to the right hand. H215O positron emission tomography was used to measure rCBF, and the constant voltage technique was used to measure NSF from the left hand. Electrodermal activity was positively related to rCBF in the left primary motor cortex (MI, Brodmann's Area 4) and bilaterally in the anterior (Areas 24 and 32) and posterior cingulate cortex (Area 23). Negative relations were observed bilaterally in the secondary visual cortex (Areas 18 and 19) and the right inferior parietal cortex (Area 39), with a tendency also for the right insular cortex (Areas 13, 15, and 16). Because results from lesion and stimulation studies in humans converge with the present imaging results, we conclude that the cingulum and the motor cortex, in addition to the parietal and possibly the insular cortex, form part of one or several distributed neural network(s) involved in electrodermal control. Because these areas also support anticipation, affect, and locomotion, electrodermal responses seem to reflect cognitively or emotionally mediated motor preparation.