Biomedical subjects

M K Mandal

Publications and source records attributed to M K Mandal.

At least 37 records · Page 2Linked to original sources

PubMed1998

Hemifacial asymmetry in emotion expressions.

We examined asymmetry in posed facial expression of emotions: happy and sad. Hemifacial composite photographs, left-left and right-right, were prepared, and subjects rated these for intensity of expressed emotion. Overall, left-left composites were judged to have expressed emotions relatively more intensely than the right-right composites. The significant Sex x Emotion interaction revealed that female expressors were judged as more expressive than male expressors in expressing sad facial emotion. Sex difference in expression of happy facial emotion was not significant.

Adult↗

PubMed1997

Processing of facial expressions of emotion and alexithymia.

OBJECTIVE: The primary objective was to examine emotional responsiveness in alexithymia. DESIGN: A quasi-experimental design was followed with the alexithymia variable being manipulated by subject stratification based on Toronto Alexithymia Scale-20-H. METHOD: Alexithymics (N = 12) and non-alexithymics (N = 12) were asked to match, label and verbally describe photographs displaying facial emotions along with TAT card II. RESULTS: Alexithymics did not differ from non-alexithymics in emotional matching and labelling tasks but had significant difficulty in verbally describing emotional expressions as evident by less duration of utterance, greater response latency and increased linguistic-type speech disruptions. Speech disruptions did not produce a group difference for TAT card II. CONCLUSION: Such difficulty in alexithymics may be associated with their inability to use emotional words in the appropriate context.

Adult↗

PubMed1997

Hemiregional variations in facial expression of emotions.

This study examined expressiveness of facial regions during posed expressions of two basic emotions: happy and sad. Two types of composite photographs were prepared: hemifacial composites of left-left (LL) or right-right (RR); and hemiregional composites involving a left-left composite in the upper part and a right-right composite in the lower part (LL/RR) of the face or vice versa (RR/LL). Participants ranked photographs of an emotion expression: normal orientation (RL), mirror reversed (LR), left facial composite (LL), right facial composite (RR) and hemiregional composites (RR/LL; LL/RR), in order of expressiveness. The hemiregional composite RR/LL was judged as most expressive followed by LL. The findings are explained in terms of the neuroanatomy of fibre projections from the left and right cerebral hemispheres to the facial muscles.

Adult↗

PubMed1996

Bilateral transfer deficit in schizophrenia: a trait marker.

Schizophrenic patients who had shown improvement over a 6-week treatment period were tested for their bilateral transfer of skill with a mirror-drawing task. Compared with first degree relatives and normal control subjects, patients showed a significant deficit in bilateral transfer of skills in terms of response accuracy both before and after treatment. These findings indicate that the deficit is an enduring functional loss in schizophrenia.

Adult↗

PubMed1996

Cross-cultural alexithymia: development and validation of a Hindi translation of the 20-Item Toronto Alexithymia Scale.

The possibility that alexithymia may be a culture-bound construct was evaluated by developing a Hindi version of the Twenty-Item Toronto Alexithymia Scale and assessing its psychometric properties in a sample of 285 normal young adults in India. The Hindi version of the scale (TAS-20-H) showed excellent cross-language equivalence with the English version. In addition, the TAS-20-H demonstrated adequate internal consistency, good test-retest reliability, and a three-factor structure consistent with the three-factor model of the original scale.

Adult↗

PubMed1996

Cerebral laterality in affect and affective illness: a review.

It is generally claimed that affect processing is a right hemisphere function. It is also claimed that right hemisphere dysfunction is characteristic of depressive illness. These claims are not accepted without controversy, and it has been found that the relationship between affect processing and affective illness in terms of intra- and interhemispheric role is not straightforward. Two types of studies were reviewed in this context: behavioral and electrophysiological. Potential confounding effects are discussed.

Affect↗

PubMed1996

Emotion-specific processing deficit in focal brain-damaged patients.

Focal brain-damaged patients (left hemisphere damage, right hemisphere damage) and hospitalized general medical patients were asked to sort test photographs into target expressions of four facial emotions, happy, sad, fear and anger. In a second task, patients were asked to match neutral photographs with these target emotion expressions in a forced-choice format. Patients were also asked to rate their mood state on a two-dimensional affect grid. Right hemisphere-damaged patients were significantly inaccurate in matching the test-target expressions of facial emotions in comparison to left hemisphere-damaged or general medical patients. Analysis of error scores indicated a bias toward negative emotions by left hemisphere-damaged patients. Congruent to their mood state, left hemisphere-damaged patients also attributed "sadness" on neutral state of expression significantly more often than in right hemisphere-damaged patients.

Adult↗

PubMed1995

Asymmetry in emotional face: its role in intensity of expression.

Normal subjects rated expressiveness of two posed facial emotions, happy and sad; the photographs were stratified in terms of intensity of expression and were prepared in composite (right-right, left-left), normal, and mirror-reversed facial orientations. The left side of the face was more expressive for intermediate intensity expressions of happiness and for least intense expressions of happiness and sadness. The right side of the face was more expressive for most intense expressions of happiness and sadness.

Adult↗

PubMed1993

The right-ear advantage in schizophrenia.

Schizophrenics, patients with affective disorder and normal controls were tested on a verbal dichotic listening task at three time periods, 0-2, 4-6 and 14-16 weeks. Schizophrenics had non-significant ear difference during the acute state of illness (0-2 weeks) and the normal right-ear advantage emerged when acuteness subsided (14-16 weeks).

Adult↗

PubMed1993

Judgment of facial expression of emotion in unilateral brain-damaged patients.

Patients with unilateral brain damage and normal controls were asked to give (1) inter-emotion judgment within the photographs of six facial emotions in terms of mutual similarities, and (2) intra-emotion judgment within the hemifacial composite photographs of an emotion in terms of intensity of expression. Right brain-damaged patients could differentiate between the emotion of happiness and all other emotions. Left brain-damaged patients differentiated between aroused-nonaroused emotions. Normal controls differentiated between positive-negative as well as aroused-nonaroused emotions. Left-left facial composites were judged to have expressed more intensely than right-right facial composites or normal/mirror-reversed facial orientations of emotions (except fear) by any group (p >.05).

Journal Article↗

PubMed1992

Exposed eye area (EEA) in the expression of various emotions.

Exposed eye area (EEA) was measured in photographs of Indian adults who modeled six emotions--happiness, sadness, fear, anger, surprise, and disgust--as well as a neutral expression. The data were analyzed with a 2 x 6 (Eyes x Emotions) factorial analysis of covariance (ANCOVA). EEA for neutral expression was used as the covariate measure. The EEAs of the two eyes did not differ significantly during the expression of emotion. The EEAs for fear and surprise were significantly larger, and the EEA for disgust was significantly smaller than those for either other emotions or neutral expression.

Adult↗

PubMed1992

Degree of asymmetry in lateral preferences: eye, foot, ear.

Lateral asymmetry in eye, foot, and ear preference was measured using a 15-item questionnaire administered to 442 subjects. Degree and magnitude of asymmetry were greatest for eye, followed by foot and ear. Intercorrelations of lateral preferences were all positive and significant. Two primary factors, eyedness and earedness, were established.

Adult↗

PubMed1992

Role of cerebral hemispheres and regions in processing hemifacial expression of emotion: evidence from brain-damage.

Patients with focal brain-damage, right or left hemisphere-damage (RHD/LHD) and anterior or posterior region-damage (ARD/PRD), and normal controls (NC) were asked to match the photographs of (left-right) hemifacial expressions of emotions, positive (happy-surprise), negative-aroused (fear-anger), negative-nonaroused (sad-disgust). Findings indicated that (a) NC subjects were significantly superior to brain-damaged patients; the difference between RHD and LHD patients was nonsignificant, and (b) ARD patients were significantly inferior to PRD patients who, in turn, were significantly inferior to NC subjects, in the perceptual matching task with hemifacial affective stimuli.

Adult↗

PubMed1991

Right brain damage impairs recognition of negative emotions.

Patients with right or left hemisphere-damage and normal control groups were asked to judge facial emotions from photographs presented in two orientations--upright, inverted. Responses were elicited with a matching and a verbal labelling task. Normal controls were significantly superior in the judgment of facial emotions than left hemisphere-damaged patients, who in turn were significantly superior than right hemisphere-damaged patients. Negative-aroused (fear, anger) and negative-nonaroused (sadness, disgust) facial expressions were recognized with significantly greater accuracy by left hemisphere-damaged patients compared to right hemisphere-damaged patients; the group difference in performance was nonsignificant for positive (happiness, surprise) emotions.

Adult↗

PubMed1990

Paralinguistic characteristics of speech in schizophrenics and depressives.

Schizophrenics, depressives, patients with anxiety neurosis and normal controls were asked to comment freely for 2 min on photographs depicting seven facial emotional expressions. Schizophrenics commented for the shortest duration of time with characteristic vocalization; depressives' speech was characterized by low initiative time latency, greater duration of utterance but fewer word-counts.

Adult↗

PubMed1990

Identification of tachistoscopically presented alphanumeric stimuli in schizophrenia.

Schizophrenics, general medical patients and non-patient controls were compared for their ability to identify tachistoscopically presented alphanumeric stimuli at six exposure durations. Schizophrenics did not differ from general medical patients but both were inferior to controls - a difference that increased as the exposure duration decreased.

Adult↗

PubMed1989

Identifying the components of facial emotion and schizophrenia.

Schizophrenics, anxiety neurotics, and nonpatient control subjects were asked to identify the emotion expressed in partial (upper-middle-lower) and full facial expression of four negative emotions: sadness, fear, anger and disgust. Groups did not differ in the ability to identify emotions from partial facial expressions, however, schizophrenics were significantly poorer than anxiety neurotics and controls in identifying emotions from full facial expressions.

Adult↗

PubMed1987

Responses to facial emotion and psychopathology.

Schizophrenics, anxious-neurotics, and nonpatient controls were asked to recognize facial affect in photographs depicting six emotions and a neutral expression. The time elapsed between presentation of the photograph and response to it was also noted. Schizophrenics were significantly less accurate at judging the expressed affect and had the largest mean response time compared to others. Preference to interact with the type of affect expressions was also analyzed. Happy and neutral expressions were chosen, while fearful and angry expressions were rejected by neurotic and control subjects. Schizophrenics were largely inconsistent in their choice.

Adolescent↗