Lapses in skin conductance responding across anatomical sites: Comparison of fingers, feet, forehead, and wrist.

The fingers are widely accepted as the gold standard for skin conductance (SC) recording, with the feet as a strong alternative. However, there are gaps in the current literature comparing these sites. There is also a great deal of interest in alternative recording sites to permit mobility, but data evaluating these are few and inconsistent.

Can you give me a hand? A comparison of hands and feet as optimal anatomical sites for skin conductance recording.

The fingers and feet have long been accepted as optimal anatomical recording sites for electrodermal activity. The available literature suggests that the feet are more responsive than the fingers. The present report compared skin conductance level (SCL) and responses (SCRs) from the left foot and the distal phalanges of the fingers on the nondominant hand among 19 participants.

Can human autonomic classical conditioning occur without contingency awareness? The critical importance of the trial sequence.

Most evidence suggests that awareness of the CS-US contingency is necessary for human autonomic conditioning. However, Schultz and Helmstetter (2010) reported unaware skin conductance conditioning using difficult-to-discriminate visual CSs. We sought to replicate these findings with procedures nearly identical to Schultz and Helmstetter among 66 participants.

The interaction of electrodermal activity and expressed emotion in predicting symptoms in recent-onset schizophrenia.

In the present study, expressed emotion (EE) was assessed among immediate family members of 94 recent-onset schizophrenia patients at initial study entry point, and patients' electrodermal activity (EDA) was measured without the presence of family members at a baseline outpatient stabilization assessment. Psychiatric symptoms were also rated, both at the baseline outpatient test and at 1-year follow-up. Electrodermal activity × expressed emotion interactions were observed at both test points.

Psychophysiological prodromal signs of schizophrenic relapse: a pilot study.

Do physiological changes occur shortly prior to psychotic relapse in schizophrenia outpatients? We addressed this question in a group of schizophrenia outpatients by measuring changes in symptoms and changes in activation of the sympathetic nervous system, as indexed by changes in skin conductance level (SCL), on a biweekly basis for between one and two years. All six outpatients exhibited heightened SCL within two weeks prior to relapse or exacerbation, compared to SCL proceeding continued remission. These results shed light on the psychotic relapse process and are consistent with neural diathesis-stress models of schizophrenia.

Better than the real thing: eliciting fear with moving and static computer-generated stimuli.

As the popularity of virtual reality as an exposure therapy increases, it is important to validate the use of computer-generated stimuli in comparison to standardized images of "real" phobic objects, such as those of the International Affective Picture System (IAPS). The present study examined physiological and subjective measures of negative affect when viewing static IAPS images, static computer-generated images and moving videos of computer-generated images of feared stimuli and other negative stimuli which were not specifically feared. For example, a picture of a spider would be a "feared" stimulus for a spider fearful participant, whereas a picture of a snake would be categorized as a "negative" stimulus for that participant.

Arousal, working memory, and conscious awareness in contingency learning.

There are wide individual differences in the ability to detect a stimulus contingency embedded in a complex paradigm. The present study used a cognitive masking paradigm to better understand individual differences related to contingency learning. Participants were assessed on measures of electrodermal arousal and on working memory capacity before engaging in the contingency learning task.

Probing attentional dysfunctions in schizophrenia: Startle modification during a continuous performance test.

Startle eyeblink modification was measured in 20 relatively asymptomatic medicated schizophrenia outpatients and 18 matched controls in order to test for deficits in early and later stages of attentional processing during a memory-load version of the Continuous Performance Test. Participants viewed a series of digits and pressed a button after the digit 7 of each 3-7 sequence. On some trials, a startling noise burst was presented either 120 or 1200 ms following cues that a response might be needed soon (the digit 3) and also following noncues.

Under what conditions can human affective conditioning occur without contingency awareness? Test of the evaluative conditioning paradigm.

The role of conscious cognitive processes in human affective conditioning remains controversial, with several theories arguing that such conditioning can occur without awareness of the conditioned stimulus (CS)-unconditioned stimulus (UCS) contingency. One specific type of affective conditioning in which unaware conditioning is said to occur is "evaluative conditioning." The present experiment tested the role of contingency awareness by embedding an evaluative conditioning paradigm in a distracting masking task while obtaining, in addition to subjective ratings of affect, both psychophysiological (skin conductance and startle eyeblink) and indirect behavioral (affective priming) measures of conditioning, along with a trial-by-trial measure of awareness from 55 college student participants.

Effects of cigarette smoking on prepulse inhibition, its attentional modulation, and vigilance performance.

Startle eyeblink modification was measured during a degraded stimulus continuous performance test following both smoking and overnight abstinence among student smokers to measure the effects of smoking on both early and late attentional processes. A group of nonsmokers was tested twice without nicotine manipulation. A startling noise was presented either 240 or 1200 ms following target and nontarget stimuli presented during the task.

A 30-year prospective follow-up study of hyperactive boys with conduct problems: adult criminality.

Objective: To compare the official arrest records for a large number of hyperactive boys (N = 179), most with conduct problems, and 75 control boys; to examine childhood IQ, socioeconomic status, and parent reports of childhood hyperactivity and conduct problems for their contribution to criminal behavior in adulthood; and to compare adult outcome for multimodality-treated (MMT) and drug-treated-only (DTO) hyperactives.

Method: We report on the official arrest history from early to mid- (18 to 38 years of age) adulthood in these 254 white subjects.

Results: Ninety one percent of subjects were followed up.

Effects of perceptual load on startle reflex modification at a long lead interval.

Inhibition of the startle eyeblink response at long lead intervals has been hypothesized to occur when attention is directed away from the modality of the startle stimulus, particularly if attention is directed to a stimulus of high perceptual load. In a test of this hypothesis, participants performed a delayed-matching-to-sample task. On each trial a pattern of dots (the sample) was followed by a second pattern of dots (the target).

Electrodermal predictors of functional outcome and negative symptoms in schizophrenia.

The ability of electrodermal variables to predict negative symptoms and functional outcome over a 1-year period in schizophrenia was investigated in 78 young, recent-onset outpatients. Patients were stabilized on standardized medication and largely free of psychotic symptoms. Higher levels of both tonic (skin conductance level, nonspecific skin conductance response rate) and phasic (number of skin conductance orienting responses) activity were associated with more negative symptoms and with a combination of poorer social and occupational outcome at 1-year follow-up.

Effects of perceptual processing demands on startle eyeblink modification.

Startle eyeblink modification was measured during a continuous performance test (CPT) with either clearly focused stimuli or visually degraded stimuli to measure the effects of early perceptual processing demands on startle modification. A startling noise was presented either 120, 240, or 1200 ms following target and nontarget CPT stimuli. In the degraded stimulus CPT, startle inhibition at 240 ms was greater following targets than nontargets and was as great during targets at 240 ms as at 120 ms, whereas in the clearly focused CPT, inhibition declined significantly from 120 to 240 ms.

Attention and prepulse inhibition: the effects of task-relevant, irrelevant, and no-task conditions.

We investigated whether attentional modulation of prepulse inhibition (PPI) is due to increased protection of processing of attended lead stimuli, decreased protection of processing of ignored lead stimuli, or a combination of both processes. Task and no-task trials, pre-cued by red and blue dots on a computer screen, were randomly intermixed. College student participants were instructed to do a tone duration judgment task on trials preceded by one color (task condition) and to do nothing on trials preceded by the other color (no-task condition).

Sensorimotor gating, orienting and social perception in schizophrenia.

Basic neurocognition and social cognition appear to influence the social impairments of persons with schizophrenia. This study examined relationships between two very basic automatic processes (i.e.

The functional relationship between visual backward masking and prepulse inhibition.

This experiment demonstrated a relationship between prepulse inhibition (PPI) of the startle eyeblink and visual backward masking in college students. It was hypothesized that recovery from backward masking effects is due in part to sensory gating, as assessed by auditory and visual PPI. Visual presentations of letters served as targets or visual prepulses in an intermixed session of backward masking and PPI.

Prepulse facilitation and prepulse inhibition in schizophrenia patients and their unaffected siblings.

Background: Deficits in schizophrenia patients and their first-degree relatives have been reported in prepulse inhibition (PPI), a phenomenon that measures an early stage of information processing (sensorimotor gating). It is less clear whether these information processing deficits extend to prepulse facilitation (PPF), which measures a later stage of generalized alerting or orienting.

Methods: This study examined three separate issues: first, whether schizophrenia patients have deficits in PPI and PPF; second, whether the siblings of patients show deficits in these processes; and third, whether prepulse duration influences the degree of the deficits.

The temporal stability of electrodermal variables over a one-year period in patients with recent-onset schizophrenia and in normal subjects.

Test-retest stability of electrodermal (EDA) variables indexing both general autonomic arousal (e.g., skin conductance level, number of nonspecific skin conductance responses) and attention to external stimuli (e.

What does electrodermal activity tell us about prognosis in the schizophrenia spectrum?

Various dysfunctions in electrodermal activity (EDA) have been found in schizophrenic patients. The present paper reviews evidence that the electrodermal dysfunctions may carry prognostic information regarding subsequent symptoms, as well as social and occupational outcome. Although the findings are not entirely consistent, heightened electrodermal activity as indicated by frequent orienting responses to innocuous stimuli, elevated skin conductance level (SCL), and frequent non-specific skin conductance responses (NS-SCR) is most often associated with poor symptomatic, social, and occupational outcome in schizophrenic patients.