Electrodermal activity as an index of arousal in schizophrenics.

Abstract

Previous reviews of research utilizing electrodermal activity as an index of arousal in schizophrenia have found no consistent differences between schizophrenics and normals, although other psychophysiological measures have shown chronic schizophrenics to be more aroused. A more detailed look at the electrodermal research, however, reveals that consistent results have been reported for two aspects of electrodermal activity: (a) habituation of responses or levels during periods of minimal stimulation, such as tones and lights of low intensity and ( 6) frequency of spontaneous electrodermal responses regardless of stimulus conditions. Both of these measures appear to reflect arousal and yield results indicating that chronic schizophrenics are overaroused.

Habituation of the Blink Reflex in Normals and Schizophrenic Patients

“…Blink responses in nonschizophrenic patients and normals decreased by 74% and 70% over 121 trials, while schizophrenic patients showed only 49% habituation. This finding extends observations of impaired habituation in some groups of schizophrenic patients which had been previously demonstrated with electrodermal measures of orienting responses to acoustic stimuli (Gruzelier & Venables, 1972;Depue & Fowles, 1973: Spohn & Patterson, 1979. The observation of impaired habituation in schizophrenia thus includes defensive responses to relatively strong stimuli as well as, in some studies, orienting responses to weaker stimuli, supporting a generalized deficit.…”

Habituation of the Blink Reflex in Normals and Schizophrenic Patients

“…Blink responses in nonschizophrenic patients and normals decreased by 74% and 70% over 121 trials, while schizophrenic patients showed only 49% habituation. This finding extends observations of impaired habituation in some groups of schizophrenic patients which had been previously demonstrated with electrodermal measures of orienting responses to acoustic stimuli (Gruzelier & Venables, 1972;Depue & Fowles, 1973: Spohn & Patterson, 1979. The observation of impaired habituation in schizophrenia thus includes defensive responses to relatively strong stimuli as well as, in some studies, orienting responses to weaker stimuli, supporting a generalized deficit.…”

The startle reflex in schizophrenia: habituation and personality correlates

“…The current habituation findings parallel those of previous studies examining autonomic response habituation to less intense, orienting stimuli (Depue and Fowles, 1973;Gruzelier et al, 1981;Hollister et al, 1994), as well as previous measures of startle response habituation in schizophrenia using different methodologies (e.g., Geyer and Braff, 1982;Braff et al, 1992. Sensorimotor gating and prepulse inhibition paradigms are by far the most common means of investigating the startle reflex in schizophrenia.…”

“…Psychophysiological studies primarily using EEG or skin conductance orienting response (SCOR) paradigms have consistently demonstrated higher resting rates of arousal, but lowered responsivity to orienting and other moderately intense stimuli in patients with schizophrenia (Venables, 1966;Venables and Wing, 1962;Dawson et al, 1992, Olbrich et al, 2001. Consistent with these findings are studies that have demonstrated reduced autonomic habituation, as assessed by electrodermal activity, to a repeatedly presented sensory stimulus (e.g., Depue and Fowles, 1973;Gruzelier et al, 1981;Hollister et al, 1994). These findings have demonstrated that schizophrenic patients show irregular response patterns over time that result in slower rates of habituation.…”

An activity-withdrawal distinction in schizophrenia: Behavioral, clinical, brain damage, and neurophysiological correlates.

“…reliable and are concordant with cardiovascular, neuromuscular, and clectrocorlical data found in many schizophrenics (Depue & Fowles, 1973).…”

Habituation of the Blink Reflex in Normals and Schizophrenic Patients

“…Blink responses in nonschizophrenic patients and normals decreased by 74% and 70% over 121 trials, while schizophrenic patients showed only 49% habituation. This finding extends observations of impaired habituation in some groups of schizophrenic patients which had been previously demonstrated with electrodermal measures of orienting responses to acoustic stimuli (Gruzelier & Venables, 1972;Depue & Fowles, 1973: Spohn & Patterson, 1979. The observation of impaired habituation in schizophrenia thus includes defensive responses to relatively strong stimuli as well as, in some studies, orienting responses to weaker stimuli, supporting a generalized deficit.…”

The startle reflex in schizophrenia: habituation and personality correlates

“…The current habituation findings parallel those of previous studies examining autonomic response habituation to less intense, orienting stimuli (Depue and Fowles, 1973;Gruzelier et al, 1981;Hollister et al, 1994), as well as previous measures of startle response habituation in schizophrenia using different methodologies (e.g., Geyer and Braff, 1982;Braff et al, 1992. Sensorimotor gating and prepulse inhibition paradigms are by far the most common means of investigating the startle reflex in schizophrenia.…”

“…Psychophysiological studies primarily using EEG or skin conductance orienting response (SCOR) paradigms have consistently demonstrated higher resting rates of arousal, but lowered responsivity to orienting and other moderately intense stimuli in patients with schizophrenia (Venables, 1966;Venables and Wing, 1962;Dawson et al, 1992, Olbrich et al, 2001. Consistent with these findings are studies that have demonstrated reduced autonomic habituation, as assessed by electrodermal activity, to a repeatedly presented sensory stimulus (e.g., Depue and Fowles, 1973;Gruzelier et al, 1981;Hollister et al, 1994). These findings have demonstrated that schizophrenic patients show irregular response patterns over time that result in slower rates of habituation.…”

An activity-withdrawal distinction in schizophrenia: Behavioral, clinical, brain damage, and neurophysiological correlates.

“…reliable and are concordant with cardiovascular, neuromuscular, and clectrocorlical data found in many schizophrenics (Depue & Fowles, 1973).…”

Habituation of the Blink Reflex in Normals and Schizophrenic Patients

“…Blink responses in nonschizophrenic patients and normals decreased by 74% and 70% over 121 trials, while schizophrenic patients showed only 49% habituation. This finding extends observations of impaired habituation in some groups of schizophrenic patients which had been previously demonstrated with electrodermal measures of orienting responses to acoustic stimuli (Gruzelier & Venables, 1972;Depue & Fowles, 1973: Spohn & Patterson, 1979. The observation of impaired habituation in schizophrenia thus includes defensive responses to relatively strong stimuli as well as, in some studies, orienting responses to weaker stimuli, supporting a generalized deficit.…”

The startle reflex in schizophrenia: habituation and personality correlates

“…The current habituation findings parallel those of previous studies examining autonomic response habituation to less intense, orienting stimuli (Depue and Fowles, 1973;Gruzelier et al, 1981;Hollister et al, 1994), as well as previous measures of startle response habituation in schizophrenia using different methodologies (e.g., Geyer and Braff, 1982;Braff et al, 1992. Sensorimotor gating and prepulse inhibition paradigms are by far the most common means of investigating the startle reflex in schizophrenia.…”

“…Psychophysiological studies primarily using EEG or skin conductance orienting response (SCOR) paradigms have consistently demonstrated higher resting rates of arousal, but lowered responsivity to orienting and other moderately intense stimuli in patients with schizophrenia (Venables, 1966;Venables and Wing, 1962;Dawson et al, 1992, Olbrich et al, 2001. Consistent with these findings are studies that have demonstrated reduced autonomic habituation, as assessed by electrodermal activity, to a repeatedly presented sensory stimulus (e.g., Depue and Fowles, 1973;Gruzelier et al, 1981;Hollister et al, 1994). These findings have demonstrated that schizophrenic patients show irregular response patterns over time that result in slower rates of habituation.…”

An activity-withdrawal distinction in schizophrenia: Behavioral, clinical, brain damage, and neurophysiological correlates.

“…reliable and are concordant with cardiovascular, neuromuscular, and clectrocorlical data found in many schizophrenics (Depue & Fowles, 1973).…”