Autonomic Discrimination Research Articles

Priming, recognition and autonomic discrimination in amnesia

Six individuals with amnesia and matched healthy controls participated. There were two objectives. First, determine whether physiological activity at encoding relates to whether a word shows autonomic priming or is recognized. Second, propose a model for understanding relationships between recognition and autonomic priming. In amnesics, ‘unrecognized’ words were associated with better autonomic discrimination and lower levels of physiological activity at encoding. In healthy participants and amnesics, ‘recognized’ words were associated with poorer autonomic priming and higher levels of physiological activity at encoding. A state-dependent, activation-fractionation-inhibition model is proposed involving an orienting response elicited by preference and search and modulated by underlying memory strength.

Facial Expression Recognition, Fear Conditioning, and Startle Modulation in Female Subjects with Conduct Disorder

BackgroundRecent behavioral and psychophysiological studies have provided converging evidence for emotional dysfunction in conduct disorder (CD). Most of these studies focused on male subjects and little is known about emotional processing in female subjects with CD. Our primary aim was to characterize explicit and implicit aspects of emotion function to determine whether deficits in these processes are present in girls with CD.MethodsFemale adolescents with CD (n = 25) and control subjects with no history of severe antisocial behavior and no current psychiatric disorder (n = 30) completed tasks measuring facial expression and facial identity recognition, differential autonomic conditioning, and affective modulation of the startle reflex by picture valence.ResultsCompared with control subjects, participants with CD showed impaired recognition of anger and disgust but no differences in facial identity recognition. Impaired sadness recognition was observed in CD participants high in psychopathic traits relative to those lower in psychopathic traits. Participants with CD displayed reduced skin conductance responses to an aversive unconditioned stimulus and impaired autonomic discrimination between the conditioned stimuli, indicating impaired fear conditioning. Participants with CD also showed reduced startle magnitudes across picture valence types, but there were no significant group differences in the pattern of affective modulation.ConclusionsAdolescent female subjects with CD exhibited deficits in explicit and implicit tests of emotion function and reduced autonomic responsiveness across different output systems. There were, however, no differences in emotional reactivity. These findings suggest that emotional recognition and learning are impaired in female subjects with CD, consistent with results previously obtained in male subjects with CD.

Automatic without autonomic responses to familiar faces: Differential components of covert face recognition in a case of Capgras delusion

Introduction. This study was designed to elucidate the relationship between different types of covert face recognition. Some patients with prosopagnosia (i.e., the profound inability to recognise previously familiar faces) nonetheless evince autonomic face recognition (elevated skin-conductance levels to familiar faces) or behavioural indices of covert recognition (i.e., priming; interference effects; matching effects; face-name learning). One prosopagnosic patient revealed both autonomic and behavioural covert face recognition-which suggests they may arise from some common basis. Method. To test this claim a patient with the Capgras delusion (i.e., holding the belief that others have been replaced by impostors, etc.) was tested on each type of covert face recognition and her results compared with agematched controls. We know that the Capgras delusion is characterised by good overt or conscious face recognition coupled with the absence of autonomic discrimination between familiar and unfamiliar faces. The question addressed here was whether, compared with age- and gender-matched controls, the patient, B.P., would show neither autonomic nor behavioural covert face recognition. Results. The answer was that, although she showed no autonomic discrimination, her performance on a priming task and a test of face/name interference were normal. The controls, as expected, revealed covert face recognition on both the autonomic and behavioural measures. Conclusions. The results imply in B.P. a clear dissociation between autonomic and behavioural measures of covert face recognition. The theoretical implications of these results are discussed.

Autonomic and Recognition Indices of Memory in Amnesic and Healthy Control Subjects

Autonomic and recognition indices were examined in six amnesic subjects of mixed aetiology and six control subjects matched with respect to age, education and intelligence. The key objectives of this study were: (a) assess amnesics level of recognition and autonomic discrimination for recently shown words compared with controls; (b) determine if amnesics' level of autonomic discrimination was preserved when compared with the control subjects' level of recognition; and (c) assess confidence in hits and false alarms. The results showed that: (1) despite showing impaired recognition, amnesics displayed significantly better autonomic discrimination; (2) the level of autonomic discrimination displayed by amnesics did not significantly differ from the control subjects' level of recognition; (3) the level of confidence expressed in false alarms and hits did not significantly differ between amnesics and controls, which is in sharp contrast to the significantly greater levels of confidence expressed by healthy subjects in hits versus false alarms. If future work shows that amnesics display preserved autonomic discrimination for novel information, then it may suggest that, at least, some amnesics can store information to an extent that is comparable to that of healthy controls.

The nicotine paradox: Effect of smoking on autonomic discrimination

Smoking reduces negative affect while it increases sympathetic nervous system activity. However, theories of emotion predict that increased autonomic arousal should increase rather than reduce negative affect. One explanation for this paradox is that nicotine interferes with perception of autonomic activity. We evaluated the effect of smoking on autonomic activity perception by measuring performance on a heartbeat detection task after a high or low dose of nicotine or not smoking. A group of nonsmokers also completed the task. Results failed to support the hypothesis. In light of previous research, the results suggest EMG perception may be more important to the negative affect reduction phenomenon than perception of autonomic activity.

Heart rate discrimination and heart rate control: A test of Brener's theory

Three experiments were conducted to examine predictions from Brener's theory regarding the relationship between autonomic discrimination and autonomic control. Experiment 1 examined the possibility that training subjects to discriminate their heart rates would enhance their skill at controlling that response. Twenty subjects participated in two sessions during which one group of 10 subjects received training (knowledge of results) on the Ashton discrimination technique. The second group performed the discrimination task but received no training. All subjects then took part in a third session of heart rate (HR) control (both increase and decrease) where half of each of the aforementioned groups received feedback during the control task, while the other half performed the HR control task without feedback. Results indicated that for the control of both HR increases and decreases, there was no significant difference between those subjects trained to discriminate their HR, and those who had received no training to discriminate HR. The second experiment investigated the hypothesis that training subjects with feedback to control their HR would enhance their capacity to discriminate their heart activity. Ten subjects participated in two sessions of HR control during which half the subjects received feedback training to increase HR. During a third session, all subjects underwent a test of discrimination ability using the Ashton technique, and no knowledge of results regarding performance was provided. Results confirmed the hypothesis. The final experiment in the series investigated the discrimination/control relationship within a problem-solving framework and used 20 subjects. Results confirmed the hypothesis that subjects forewarned at the time of discrimination training that a heart rate control task was to follow would perform better than 10 subjects receiving no forewarning of the task objective. This effect took place independently of cardiac discrimination ability. A second finding from this experiment was that subjects trained to discriminate heart rate were better able to increase heart rate than untrained subjects. This result contradicts that of Experiment 1, and reasons for this anomaly are discussed in detail.

Allocation of cognitive processing capacity during human autonomic classical conditioning.

In each of two experiments, allocation of cognitive processing capacity was measured in college-student subjects during autonomic discrimination classical conditioning. A 7.0-sec delay paradigm was used to establish classically conditioned responses to a reinforced visual conditioned stimulus (CS+). Electrodermal responses were the primary measures of autonomic classical conditioning. Allocation of processing capacity was measured by monitoring performance on a secondary reaction-time (RT) task. The auditory secondary-task RT signal was presented before, and 300, 500, 3500, 6500, and 7500 msec following CS onset. The RT signal was also presented following properly and improperly cued shock unconditioned stimuli (UCSs). Significant discrimination classical conditioning was obtained in both experiments. Comparison with control subjects who did not receive the RT signals indicated that the presence of the RT signals did not interfere with the development of classical conditioning. Four principal findings were obtained with the secondary-task RT measure. First, RTs to signals presented during CS+ were consistently slower than RTs to signals presented during CS-. This finding indicates that greater capacity allocation occurred during CS+ than CS- and is consistent with recent cognitive interpretations of classical conditioning. Second, the largest capacity allocation (i.e., slowing of RTs) occurred 300 msec following CS+ onset. This finding is consistent with the notion that subjects are actively processing the signal properties of the CS+ at 300 msec following CS+ onset. Third, presentation of the UCS when improperly cued (following CS-) significantly increased capacity allocation, whereas presentation of the same UCS when properly cued (following CS+) did not affect capacity allocation. These findings indicate that subjects were actively prepared for the UCS following CS+ but not following CS- and that a surprising UCS elicits greater capacity allocation than does an expected UCS. Fourth, large electrodermal responders to the CSs exhibited patterns of capacity allocation during the CSs, particularly during the CS+, different from those of small electrodermal responders. In particular, they exhibited significantly longer RTs at 300 msec after CS+ onset than did the small responders, followed by a shortening of RT at 500 msec relative to the small responders. This finding suggests that large electrodermal responders devote greater processing capacity to significant environmental stimuli than do small responders and that their processing may begin and be completed more rapidly. All in all, the data indicate the complexity of the cognitive processes that occur during human classical conditioning and the usefulness of the secondary-task technique in integrating conditioning theories and psychophysiology with cognitive psychology.

Allocation of cognitive processing capacity during human autonomic classical conditioning.

In each of two experiments, allocation of cognitive processing capacity was measured in college-student subjects during autonomic discrimination classical conditioning. A 7.0-sec delay paradigm was used to establish classically conditioned responses to a reinforced visual conditioned stimulus (CS+). Electrodermal responses were the primary measures of autonomic classical conditioning. Allocation of processing capacity was measured by monitoring performance on a secondary reaction-time (RT) task. The auditory secondary-task RT signal was presented before, and 300, 500, 3500, 6500, and 7500 msec following CS onset. The RT signal was also presented following properly and improperly cued shock unconditioned stimuli (UCSs). Significant discrimination classical conditioning was obtained in both experiments. Comparison with control subjects who did not receive the RT signals indicated that the presence of the RT signals did not interfere with the development of classical conditioning. Four principal findings were obtained with the secondary-task RT measure. First, RTs to signals presented during CS+ were consistently slower than RTs to signals presented during CS-. This finding indicates that greater capacity allocation occurred during CS+ than CS- and is consistent with recent cognitive interpretations of classical conditioning. Second, the largest capacity allocation (i.e., slowing of RTs) occurred 300 msec following CS+ onset. This finding is consistent with the notion that subjects are actively processing the signal properties of the CS+ at 300 msec following CS+ onset. Third, presentation of the UCS when improperly cued (following CS-) significantly increased capacity allocation, whereas presentation of the same UCS when properly cued (following CS+) did not affect capacity allocation. These findings indicate that subjects were actively prepared for the UCS following CS+ but not following CS- and that a surprising UCS elicits greater capacity allocation than does an expected UCS. Fourth, large electrodermal responders to the CSs exhibited patterns of capacity allocation during the CSs, particularly during the CS+, different from those of small electrodermal responders. In particular, they exhibited significantly longer RTs at 300 msec after CS+ onset than did the small responders, followed by a shortening of RT at 500 msec relative to the small responders. This finding suggests that large electrodermal responders devote greater processing capacity to significant environmental stimuli than do small responders and that their processing may begin and be completed more rapidly. All in all, the data indicate the complexity of the cognitive processes that occur during human classical conditioning and the usefulness of the secondary-task technique in integrating conditioning theories and psychophysiology with cognitive psychology.

Autonomic classical conditioning as a function of awareness of stimulus contingencies

Two groups of 32 college students were presented compound CSs (lights and tones presented simultaneously) during a classical conditioning paradigm. By means of a masking task and verbal instructions, a partially informed group was made aware of only the visual CS's contingency with the UCS, while a fully informed group was made aware of both the visual and auditory contingencies. Autonomic indices of conditioning (electrodermal responses, heart rate, and digital pulse volume) were later measured to the individual component CSs and to various compound CSs. It was found that: (1) the partially informed group exhibited conditioning exclusively to the visual CS+ and to compounds which included the visual CS+, while (2) the fully informed group exhibited conditioning to both visual and auditory CS+s. The results confirm the importance of awareness in human autonomic discrimination classical conditioning. It is suggested that human autonomic conditioning may be usefully conceptualized as an information processing task with the autonomic indices of conditioning reflecting central cognitive processes.

Classically conditioned autonomic discrimination and tryptophan uptake in chronic schizophrenia.

ABSTRACTThe relationship of tryptophan uptake (TU) with heart period decrement discrimination (but not with HPinc and SCinc) was significant and negative in 22 schizophrenic patients (r =−.42). This is consistent with the idea that a blood protein factor in the patient, responsible for increased TU, a precursor of serotonin, may produce a limbic malfunction, one consequence of which is impaired motivational learning aptitude. HPinc and SCinc discrimination was statistically greater in 22 normals than in the 22 patients. This is consistent with the literature and, in particular, with the idea that schizophrenic patients may be characterized in terms of impaired limbic or motivational learning aptitude.

Efficiency of GSR detection of information as a function of stimulus set size.

ABSTRACTThe reported studies attempted to evaluate the influence of stimulus set size on the efficiency of detection of information through the analysis of GSR responses. Three stimulus set size variations of a standard card detection test were employed. No significant reduction in absolute detection scores was found as the number of cards was increased, and an analysis based on the Theory of Signal Detection also suggested better autonomic discrimination as the stimulus set size increased.The results suggest that the subject responds to the stimuli by dividing them into a single relevant stimulus and a reject category containing all others.

Autonomic and verbal discrimination of a subliminally learned task.

An examination of subliminal perception was made by employing classical conditioning techniques at a subliminal level. 17 Ss were presented 10 nonsense syllables at a subliminal level, 5 of which were paired with an electric shock. Ss were then administered 4 tests for discrimination immediately thereafter. The conclusions were that the subception effect described in prior studies can be empirically verified and that classical conditioning can take place at a level below conscious awareness.

Awareness of stimulus relationships and physiological generality of response in autonomic discrimination.

I should like to describe some data collected in the laboratory of the Psychiatry Department at the Albert Einstein College of Medicine which reflect two phases of our interests in conditioned autonomic discrimination in man. The first phase concerns subjective awareness, or the ability to verbalize essential aspects of the experimental situation. The second concerns the physiological generality, or the amount of spread among organs, of autonomic discrimination in man.

Autonomic discrimination without awareness: A study of subception.

Autonomic discrimination without awareness: A study of subception.