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M Katsikitis

Publications and source records attributed to M Katsikitis.

15 recordsLinked to original sources
PubMed2001

A generalised deficit can account for problems in facial emotion recognition in schizophrenia.

Neuroimaging research has shown localised brain activation to different facial expressions. This, along with the finding that schizophrenia patients perform poorly in their recognition of negative emotions, has raised the suggestion that patients display an emotion specific impairment. We propose that this asymmetry in performance reflects task difficulty gradations, rather than aberrant processing in neural pathways subserving recognition of specific emotions. A neural network model is presented, which classifies facial expressions on the basis of measurements derived from human faces. After training, the network showed an accuracy pattern closely resembling that of healthy subjects. Lesioning of the network led to an overall decrease in the network's discriminant capacity, with the greatest accuracy decrease to fear, disgust and anger stimuli. This implies that the differential pattern of impairment in schizophrenia patients can be explained without having to postulate impairment of specific processing modules for negative emotion recognition.

Anger↗
PubMed2001

The 'expert' in problem-based and case-based learning: necessary or not?

BACKGROUND: Problem-based learning (PBL) and other small-group teaching methods which incorporate principles of adult learning, are exciting innovations in medical education. In the application of these methods to medical curricula many schools have introduced non-expert tutors. However, research evaluating the effectiveness of non-expert lead teaching has been inconclusive. AIM: The present study aim was to compare the outcome of teaching in small groups facilitated by either an 'expert' or a 'non-expert' tutor, in a single topic area. METHOD: Fourth-year medical students were allocated randomly to teaching of eating disorders either by a non-expert or an expert tutor. Outcomes were evaluated by (i) a knowledge test, and (ii) self-report ratings by tutors and students of their learning methods and other qualities. RESULTS: The study found that while the non-expert tutor was rated more highly for her group management skills, and she also rated her students more highly in the area of oral communication, students who were taught by the expert scored higher in the end-of-course test in the topic area. CONCLUSION: The findings suggest that caution should be exercised, and the need for more research before widespread adoption of teaching by non-expert tutors.

Education, Medical↗
PubMed1997

The classification of facial expressions of emotion: a multidimensional-scaling approach.

Photographs (study 1) or line-drawing representations (study 2) of posed facial expressions and a list of emotion words (happiness, surprise, fear, disgust, anger, sadness, neutral) were presented to two groups of observers who were asked to match the photographs or line drawings, respectively, with the emotion categories provided. A multidimensional-scaling procedure was applied to the judgment data. Two dimensions were revealed; pleasantness--unpleasantness and upper-face--lower-face dominance. Furthermore, the similarity shown by the two-dimensional structures derived first from the judgments of photographs and second from the line drawings suggests that line drawings are a viable alternative to photographs in facial-expression research.

Emotions↗
PubMed1996

A controlled study of facial mobility treatment in Parkinson's disease.

The aim of this study was to evaluate the effects of orofacial physiotherapeutic treatment (OPT) on the facial mobility of Parkinson's disease (PD) sufferers. Sixteen participants with PD were allocated randomly to either the Treatment group or the Control group. A short interview between the physiotherapist and each subject was videotaped, and 10 random frames of the videotape were selected to be used in the facial expression assessment. The quantification of facial expressions was achieved by using an objective microcomputer-based measurement system, based on a mathematical model of the face (FACEM). A facial outline is obtained, as well as 12 facial measures, which represent distances between key facial landmarks. The facial assessment was performed on 3 separate occasions, that is, baseline (pretreatment), posttreatment, and follow-up (4 weeks later). A repeated measures analysis of variance (MANOVA) revealed a significant main effect of Time and a significant interaction effect between Time and Group for the Mouth-Opening Measure, suggesting that after treatment, members of the Treatment group opened their mouths to a greater degree than members of the Control group. Within the Treatment group, significant differences between pretreatment and posttreatment scores (MANOVA) were found for Mouth-Opening Measure and Mid-Top-Lip Measure. Similarly, Mouth-Opening Measure, Mid-Top-Lip Measure, Lower-Lip Thickness Measure, Top Eyelid/Iris Intersect Measure and Lower Eyelid/Iris Intersect Measure were significant across time from baseline to follow-up in the Treatment group only. No significant differences were found on any of the facial measures during the same period for members of the Control group. These findings suggest that OPT can improve facial movement and that this benefit extends in time, beyond the period of OPT itself. Such an increase in facial mobility can be expected to modify the "Parkinsonian facies" and facilitate the display of facial expressions.

Aged↗
PubMed1994

The classification of facial emotions: a computer-based taxonomic approach.

This study investigated whether the six 'fundamental' expressions of emotion each have configurational properties which would result in their being grouped into classes by a classification program. Twenty-three actors posed the six 'fundamental' emotions of happiness, surprise, fear, disgust, anger, sadness and a neutral expression. Still images of these videotaped expressions were digitised and distance measures between facial landmark points were obtained. These measures were subjected to a numerical taxonomy procedure which generated five classes. Class 1 contained almost 70% of the happiness expressions. In Class 2 the majority of expressions were of surprise. Each of classes three, four and five consisted of mixtures of emotions. Class 5 however, was distinguished from all other classes by the complete absence of happiness expressions. The typical facial appearance of members of each class is described (based on distance measures). These findings support the salience of happiness among emotional expressions and may have implications for our understanding of the brain's function in the early development of the human infant as a social organism.

Adult↗
PubMed1991

A controlled quantitative study of facial expression in Parkinson's disease and depression.

A microcomputer-based approach to the quantification of facial expression was used to measure and compare the smiling behavior of a group of Parkinson's disease sufferers, a group of patients with major depression, and a control group of comparable age. Subjects were asked to view a series of amusing slides and their expressions were recorded. The most animated smile for each subject was chosen for analysis and scores on 12 computer-generated measures were obtained using the Facial Expression Measurement program. These measures are end-lip measure, mouth width measure, mouth-opening measure, mid-top measure, mid-lower lip measure, top lip-thickness measure, lower lip-thickness measure, eye-opening measure, top eyelid/iris intersect measure, lower eyelid/iris intersect measure, inner eyebrow measure, and mid-eyebrow measure. The depressed group differed significantly from the other groups, with higher scores on end-lip measure, mid-top lip measure, and mid-eyebrow measure. All subjects completed the Levine-Pilowsky Depression Questionnaire. The depressed patients obtained higher depression scores than the parkinsonian group, who in turn had significantly higher depression scores than the control group. The depression score was correlated with end-lip measure, mouth width measure, mid-top lip measure, eye-opening measure, and mid-eyebrow measure in the population as a whole. A significant negative correlation emerged between the depression score and mid-eyebrow measure in the depressed group. Both the depressed group and the parkinsonian group were found to smile significantly less often during the slide session when compared with the control group. These results are discussed in the light of earlier findings.

Affect↗
PubMed1990

Postoperative pain experiences: relevant patient and staff attitudes.

Postoperative pain continues to occur, despite both advances in analgesic techniques and recognition of the damaging effect of pain upon recovery. This study set out to describe the pain experiences of successive cholecystectomy patients in a large teaching hospital, using three different pain measures and self-reports of anxiety and pain-related attitudes and experiences. Nurses and doctors in surgical wards provided parallel information about their pain-related attitudes and practices. A substantial proportion of patients suffered significant postoperative pain, apparently related to their fear of addiction and reluctance to ask for extra analgesic help. Nurses were more convinced than patients that patients should have more control of their own pain relief. Barriers to effective pain relief are seen to include cognitive, attitudinal and systemic factors; some suggestions are offered for reform of relevant hospital practices.

Analgesics, Opioid↗
PubMed1988

A study of facial expression in Parkinson's disease using a novel microcomputer-based method.

The aim of this study was to compare the smiling behaviour of a group of Parkinson's disease sufferers with a control group of a similar age using a novel microcomputer-based approach, which utilises a mathematical model of the face to quantify facial expression. The findings indicate that the Parkinson's group differed from the control group in the frequency of smiling while watching a series of cartoons and in the degree of mouth opening during smiling. Both groups completed the Levine-Pilowsky Depression questionnaire, and patients with Parkinson's disease had significantly higher depression scores than those of the control group. Significant negative correlations between depression score and frequency of smiling, and depression score and inner eyebrow separation were also found.

Aged↗
PubMed1987

Medical professional support and cardiac rehabilitation of males and females.

In order to operationalize the concept of 'social support', myocardial infarction (MI) survivors were asked to describe others who had been 'specially helpful' to them during their recovery, using an adjective checklist. Doctors were more likely to be described with words denoting expertise than were friends and family. However, about a third of the adjectives used to describe doctors referred to emotional support. Subjects who had not mentioned a doctor amongst their 'specially helpful' others during the recovery period differed from those who had, in sex distribution, ideas about the cause of the MI, and rehospitalization experiences. Results have implications for the form of medical professional support valued by MI survivors, and also for alternative coping strategies used with apparently equal success by a proportion of survivors.

Adult↗
PubMed1987

Illness behaviour and general practice utilisation: a prospective study.

The Illness Behaviour Questionnaire (IBQ) was used to compare general practice patients who presented physical complaints in the absence of objective pathology, with those in whom the presence of pathology was established. Patients without pathology showed a greater conviction as to the presence of disease, and greater degrees of anxiety, depression and irritability. Males and females differed on their IBQ scores: males showing more disease conviction, somatic focusing and hypochondriasis. Utilisation of general practitioner services (as indicated by the number of visits in the six months subsequent to completing the IBQ) was associated with greater age, and for the group as a whole, utilisation was predicted by higher scores on the following IBQ scales: disease conviction, affective disturbance and disease affirmation. This was also the case for males, but in females only affective disturbance correlated with a greater number of visits. Four patterns were delineated in the relationship between age, illness behaviour variables, the presence or absence of objective pathology, and G.P. contacts.

Adult↗
PubMed1984

The Illness Behavior Questionnaire as an aid to clinical assessment.

The Illness Behavior Questionnaire (IBQ) is a 62-item self-report instrument that provides information relevant to the delineation of a patient's attitudes, ideas, affects, and attributions in relation to illness. The scores generated are described, and nine clinical vignettes are presented, together with IBQ score profiles and interpretations to illustrate the manner in which the latter may complement other clinical data. The ways in which individuals react to their own health status is becoming of greater importance as the taking of responsibility for one's own health is increasingly emphasized. The IBQ provides information that should be relevant to the management of patients, regardless of the specific nature of their illness.

Adult↗
PubMed1983

Cohort analysis of suicide rates in Australia.

Age-specific cohort analysis of Australian suicide rates confirmed recent Canadian and American reports of a substantial increase in suicide rate among young age groups. However, it was unable to replicate fully the previous findings that not only did successive birth cohorts have higher suicide rates, but that at each successive five-year period they had higher suicide rates than preceding cohorts had at that age. The major differences could be explained on the basis of the introduction of legislation that restricted the prescription of sedatives. This suggests that although there may be early and lasting effects on successive birth cohorts contributing to a general increase in cohort-specific suicide rates in the countries examined, such rates also can be influenced by changing environmental factors more immediately related to the suicide itself.

Adolescent↗
PubMed1983

Depressive illness and dependency.

The relationship has been examined in depressed in-patients between type of depression (as categorised by the Levine-Pilowsky Depression Questionnaire) and dependency (as measured by the Interpersonal Dependency Inventory) at time of discharge. No relationship could be demonstrated between dependency and depressive category.

Adaptation, Psychological↗