PubMed Health⌕ Search

Biomedical subjects

W Boucsein

Publications and source records attributed to W Boucsein.

34 records · Page 2Linked to original sources
PubMed1978

[Multivariate investigation of reactions to tranquilizers dependent on personality variables (author's transl)].

5 mg of diazepam as well as 2.5, 5, and 10 mg of a substance from the thienodiazepine series (Bay g 5653) were compared with a placebo, following a double-blind procedure. The 149 male student volunteers were classified into introverts and extraverts. For 17 test variables including subjective and physiological measures, as well as psychomotoric and cognitive achievement variables, a 2 x 5-factorial MANOVA was computed. Effects of medication and of interactions between introversion/extraversion and medication were highly significant. Correlations of test variables with composite scores indicated that medication effects could be shown best with objective tests, while the interactions between introversion/extraversion and medication could be shown better with subjective variables. Results were discussed together with those of an earlier univariate analysis of the data using emotional stability/lability as a personality variable.

Adult↗
PubMed1976

The effect of chlordiazepoxide on the anticipation of electric shocks.

The action of 20 mg chlordiazepoxide upon two different anxiety-evoking conditions in comparison with a control condition was investigated in a double-blind, placebo controlled study with 90 healthy male students. The Ss were told to expect an electric shock two times as strong under one condition and five times as strong under the other one in relation to a shock they had previously found unpleasant. During the anticipation interval of 20 min duration HR, GSR, respiration rate, and a rating of subjective emotional arousal were continuously recorded. The greatest effects of stress could be observed within the last 2 min of the anticipation interval, while interactions between drug- and stress-conditions occurred only at the beginning of the 20-min interval. Under the strong stress condition chlordiazepoxide showed an anxiety-reducing effect, under the control condition, however, paradoxical effects.

Anxiety↗
PubMed1976

[Psychological-experimental study on the effects of tranquilizers (diazepam and a drug under investigation) considering personality variables (author's transl)].

Three doses of a substance from the thieonodiazepine series (BAY g 5653), a drug under investigation, were tested as well as 5 mg of diazepam and a placebo, including a condition with no medication. 180 healthy male student volunteers, previously classified according to emotional stability/lability, took part in the study following a double-blind procedure. All subjects received white noise discontinuously with an intensity of 95 dBA. From the subjective and objective test variables employed, only the results from an adjective check list were evaluated fro the present paper. Diazepam showed some typical but not very strong effects. BAY g 5653 showed also little difference from placebo. There were some positive effects in the group of emotionally stable under stress.

Arousal↗
PubMedDate not supplied

Classical conditioning and information processing: different mechanism for prepared and unprepared stimuli?

Although learning without awareness conflicts with recent theories of classical human Pavlovian conditioning, there is at least one type of conditioning in which CS-US contingency is processed without awareness--the so-called prepared conditioning. Therefore, presenting a secondary reaction time probe to measure the amount of information processing capacity required should produce interference with the secondary task in unprepared, but not in prepared conditioning, since in the latter information should be processed in parallel. In a previous study, the authors could not find differences between both types of conditioning, neither in reaction time nor in electrodermal indicators of information processing. The present study was conducted to replicate and extend these findings, using a differential autonomic conditioning paradigm. One half of 42 subjects received spider and snake slides as prepared stimuli, while the other half received flower slides as unprepared stimuli. Both kinds of stimuli were used as CS+ and as CS-. An electric shock served as unconditioned stimulus. During 24 acquisition and 24 extinction trials, electrodermal and heart rate responses, as well as reaction times to probe stimulus were recorded. The results revealed significant conditioning effects in terms of CS-/CS+ differences. However, no differences were found between prepared and unprepared stimuli, neither in autonomic measures nor in reaction time. Again, our results are in favor of serial information processing in both prepared and unprepared stimuli, suggesting that the so-called prepared conditioning may be treated as a subclass of classical autonomic conditioning instead of forming a specific class of learning.

Adult↗
PubMedDate not supplied

A psychophysiological model of emotion space.

Despite a wide variety of emotions that can be subjectively experienced, the emotion space has consistently revealed a low dimensionality. The search for corresponding somato-visceral response patterns has been only moderately successful. The authors suggest a solution based on an assumed parallelism between emotion coding and color coding. According to the color detection model proposed by Sokolov and co-workers, neurons responsible for color detection are triggered by a combination of excitations in a limited number of input cells. Similarly, a limited number of input channels may feed complex emotion detectors being located on a hypersphere in a four-dimensional emotion space, the three angles of which correspond to emotional tone, intensity, and saturation, in parallel to hue, lightness, and saturation in color perception. The existence of such a four-dimensional emotion space in the subjective domain is shown by using schematic facial expressions as stimuli. A neurophysiological model is provided in which reticular, hypothalamic, and limbic structures constitute input channels of an emotion detecting system, thus acting as the first layer of emotion predetectors. Hypothalamic neurons with differential sensitivity for various transmitters may elicit a subsequent selective activation in a second layer of predetectors at the thalamic level. The latter are suggested to trigger emotion detectors located in cortical areas, the action of which should be revealed by measures of central nervous system activity. Preliminary results from evoked potential studies show that switching between schematic faces that express different emotions may be used as an objective measure for establishing a psychophysiological emotion space.

Emotions↗
PubMedDate not supplied

Electrodermal Pavlovian conditioning with prepared and unprepared stimuli.

One-trial learning referred to by Guthrie has been suggested to occur in autonomic conditioning, if the conditional stimuli (CSs) are so-called prepared ones. To test this idea, half of 28 subjects were given spider or snake slides as "prepared" CSs, while the remainder were given neutral slides as "unprepared" CSs. A shock was employed as the unconditional stimulus (UCS), with a CS-UCS interval of 8 seconds. Electrodermal activity and probe reaction times were the dependent measures of conditioning, conceived in cognitive, information-processing terms as the learning of the CS/UCS contingency. Evidence for the usual CS/UCS contingency learning emerged in both indicators, and during both acquisition and extinction, but none for one-trial learning, perhaps because the UCS was insufficiently aversive.

Adult↗
PubMedDate not supplied

Electrodermal activity as an indicator of information processing in a nonaversive differential classical conditioning paradigm.

Most investigations of information processing in human Pavlovian autonomic conditioning focussed on the role of awareness of the contingency of the conditioned stimulus (CS) and the unconditioned stimulus (UCS). While in these studies only the qualitative information of the CS (UCS occurring vs not occurring) was varied, the present experiment was designed to vary the quantitative information of the CS. In a differential conditioning paradigm, using a letter reproduction task as nonaversive UCS, electrodermal responses to different degrees of CS information content were investigated. Twenty subjects experienced two different conditions in a within subject design. In one condition only the number of letters used in the following UCS was presented as CS+, while in the other condition the CS already contained the whole UCS information. Both conditions led to significant differences in magnitudes of electrodermal responding.

Adult↗
PubMedDate not supplied

Psychophysiological and behavioral differences as a function of age and Parkinson's disease.

Differences related to age and to specific neurological (Parkinsonian) damage were studied by contrasting, respectively, old (mean age 64 years) and young (27 years) subjects (N = 15), and old-normal (N = 15) and old-Parkinsonian (N = 15) subjects. Both behavioral as well as psychophysiological dependent variables were employed. The behavioral measure was performance on a discrimination learning task, while the psychophysiological measures were based on habituation to a repeated tone stimulus and on a Pavlovian differential conditioning preparation. The behavioral task showed predominantly age-related differences, with the young learning faster. Another age-related difference was interpreted as showing a more insight-like learning process in the young. Response-bias (beta) values did not differ between groups. Age-related differences also emerged more clearly than specific-neurological-damage differences in the psychophysiological data. The older subjects manifested markedly less autonomic conditioning, which was probably due to a lowering of reactivity, as well as the emergence of habituation to the (loud-noise) unconditional stimulus. A correlational analysis of discrimination conditioning also yielded age-related differences. Most notably, reactivity played a greater role in conditioning in the old than in the young subjects. The results illustrated how psychophysiological measures can provide information that complements those provided by behavioral measures.

Adult↗
PubMedDate not supplied

The color-vision approach to emotional space: cortical evoked potential data.

A framework for accounting for emotional phenomena proposed by Sokolov and Boucsein (2000) employs conceptual dimensions that parallel those of hue, brightness, and saturation in color vision. The approach that employs the concepts of emotional quality. intensity, and saturation has been supported by psychophysical emotional scaling data gathered from a few trained observers. We report cortical evoked potential data obtained during the change between different emotions expressed in schematic faces. Twenty-five subjects (13 male, 12 female) were presented with a positive, a negative, and a neutral computer-generated face with random interstimulus intervals in a within-subjects design, together with four meaningful and four meaningless control stimuli made up from the same elements. Frontal, central, parietal, and temporal ERPs were recorded from each hemisphere. Statistically significant outcomes in the P300 and N200 range support the potential fruitfulness of the proposed color-vision-model-based approach to human emotional space.

Adult↗
PubMedDate not supplied

Revisiting the learning-without-awareness question in human Pavlovian autonomic conditioning: focus on extinction in a dichotic listening paradigm.

Numerous studies have indicated that, consistent with current "cognitive" accounts of information processing, human Pavlovian autonomic discrimination acquisition cannot occur without awareness of the CS-US relationship. However, extinction studies have suggested that awareness is not necessary, findings that, in information-processing terms, have been explained by assuming that the processing by the extinction stage is parallel (automatic) rather than serial (controlled). This explanation was tested in an 80-subject study. The first, acquisition phase was a standard semantic differential conditioning arrangement with a 96-db white noise as US, and a "long" CS-US interval of 8 s, with ten trials each of CS+ (paired with US) and CS- (unpaired) trials. In extinction (USs omitted), in order to obtain non-autonomic indices of processing and thereby test the information-processing account of "unaware" autonomic conditioning during extinction, a dichotic listening task was implemented, with the CSs presented in the unattended channel (ear), while the subject had to perform a semantic differential reaction task in an attended-to channel (other ear). In early extinction, the electrodermal response occurring at an interval of 9-15 s after CS onset (i.e., following placement of the US during acquisition) and the finger-pulse-volume response occurring at an interval of 4-11 s after CS onset both showed reliable conditioning, but reaction-time and subjective-report data for the recognized critical words indicated serial rather than parallel processing of the CSs during extinction.

Adult↗
PubMedDate not supplied

Effects of vasopressin on the habituation of the orienting reaction in men.

Effects of arginine-vasopressin (AVP) on the habituation of the orienting reaction and response to stimulus mismatch were investigated in a between-group design with 40 healthy male volunteers using skin conductance and heart rate responses as dependent measures. Twenty-one 1000 Hz tones of 90 dB(A) intensity and 2 s duration were presented with alternating intervals of 20 and 140 s. Stimulus mismatch responses were analyzed to the tones after the long intervals and to a change of the interval duration. The expected prevention of habituation as an indicator of a general stimulus-related increase of phasic arousal under AVP could not be confirmed. There were no differences between the AVP and the placebo group in the skin conductance and heart rate responses. The interval change did not provoke a dishabituation reaction, but responses to the tones after the long intervals were reliably enhanced. However, AVP did not increase the reaction to stimulus mismatch. It is concluded that autonomic indicators of the habituation of the OR remain unaffected by AVP.

Acoustic Stimulation↗