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A Thapar

Publications and source records attributed to A Thapar.

At least 55 records · Page 3Linked to original sources
PubMed1996

A twin study of antisocial and neurotic symptoms in childhood.

There is some evidence to suggest that the role of genetic and environmental influences may vary for different types of psychiatric symptoms in childhood. The aim of this study was to examine to what extent genetic and environmental factors influence parent-rated conduct and neurotic symptoms in childhood and adolescence, using data obtained from a systematically ascertained sample of twins (198 same sex pairs) aged between 8 and 16 years. For symptoms of antisocial behaviour, transmission could be explained entirely by shared environmental factors. Social class effects were also found to have a significant influence on antisocial behaviour, although these effects only accounted for a small proportion of the variance explained by shared environmental factors. In contrast, transmission of neurotic symptoms was best explained by additive genetic influences alone with no contribution from shared environment. Non-shared environmental factors accounted for a substantial component of the variation for both antisocial behaviour and neurotic symptoms.

Adolescent↗
PubMed1996

Genetic influences on life events in childhood.

Until recently, life events were considered as chance occurrences. However, there is now increasing evidence that reported life events, at least in adult life are not random. Life events not only tend to cluster in families but also appear to be influenced by genetic factors. The aim of this study was to investigate whether genetic factors also influence reported life events in childhood using a systematically ascertained sample of 376 twin pairs aged 8 to 17. Overall, reported life events in this younger population were found to be heritable. However, the degree of genetic and environmental influence appeared to vary across the sexes, at least for parent-rated life events and according to whether life events were rated by the parents or the children themselves. Genetic influences appeared to be more important for self reports, suggesting that individual differences in cognition play a role in reporting life events.

Adolescent↗
PubMed1996

Reverse-interference effect in free recall.

D. J. Burns (1989) demonstrated that free recall of second-list response terms was better in an interference (A-B, A-C) condition than in a control (D-B, A-C) condition. This reversal of the traditional interference effect was referred to as the reverse-interference effect. Results from Experiments 2-4 in this article discounted several possible explanations of the reverse-interference effect, and the results from Experiment 5-7 supported a stimulus accessibility account of the reverse-interference effect. That is, when asked for free recall of the response terms, participants covertly retrieved stimulus terms to serve as cues for the responses. The reverse-interference effect reflects the greater accessibility of stimulus terms in the interference condition than in the control condition.

Adult↗
PubMed1996

Interruptions during general practice consultations--the patients' view.

BACKGROUND: Although most aspects of the consultation have been extensively reported there is very little information on the effects of interruptions on the consultation. OBJECTIVE: We wished to discover the patients' view of interruptions. METHODS: In this pilot study the sources and frequency of interruptions to the consultations of a single general practitioner were measured. The effects of interruptions on 102 patients whose consultations were interrupted were then ascertained using a simple questionnaire. RESULTS: The overall interruption rate was found to be 10.2%. The telephone was the commonest source of interruption, accounting for 50% of interruptions. Although most patients did not perceive the interruption as having an important effect on the consultation, 20% of patients did feel that the interruption had a bad effect on the consultation and 40% of patients felt it would have been better not to have been interrupted. A majority of patients (52%) did not feel that the reason for the interruption was important. Although most patients did not feel affected by the interruption, a significant minority (18%) of patients had a strongly negative emotional response to the interruption. CONCLUSIONS: In view of these findings the need for further work has been highlighted.

Adolescent↗
PubMed1996

Attitudes of general practitioners to caring for people with learning disability.

BACKGROUND: The views of general practitioners on their increasing role in caring for people with learning disability in the community are not known. AIM: A study was carried out to assess the views of general practitioners with regard to providing routine care, organizing health promotion and specific health checks for people with learning disability and the role of specialists. METHOD: A postal questionnaire was sent to all 242 general practitioners in Gwent, south Wales. Participants had to mark their level of agreement with 20 attitude statements regarding learning disability. RESULTS: A total of 126 general practitioners (52%) responded. Respondents generally agreed that general practitioners were responsible for the medical care of people with learning disability. Respondents tended to be opposed to providing regular structured health promotion for people with learning disability, such as annual health checks and assessing hearing and eyesight. Specialist services were generally valued by respondents. CONCLUSION: General practitioners largely accepted their role as primary health care providers for people with learning disability. In contrast, their role as providers of health promotion for this patient group was not generally accepted. Further research into the appropriateness and opportunity costs of health screening for people with learning disability is needed.

Attitude of Health Personnel↗
PubMed1995

Childhood hyperactivity scores are highly heritable and show sibling competition effects: twin study evidence.

Hyperactivity has consistently been shown to be familial. Until recently however, due to a lack of systematic twin evidence, it has remained uncertain to what extent familial transmission can be explained by genetic factors. We used a systematically ascertained population-based sample of twin pairs aged between 8 and 16 years old to explore the role of genetic influences on maternally rated hyperactivity scores. Hyperactivity scores were found to be substantially heritable. The data were best explained by a model which incorporated sibling competitive effects as well as additive genetic factors. These findings suggest not only that hyperactivity scores are influenced by genetic factors but that sibling interaction effects are also of importance.

Adolescent↗
PubMed1995

A strategic account of the cue-depreciation effect.

A word fragment is less likely to be completed if it is presented incrementally (R______P, R____R _ P, R_I__R_P, R_I__R O P) than if it is presented all at once (e.g., R_I__R O P). This phenomenon is known as the cue-depreciation effect. The present study examined the role of strategies in this phenomenon. The magnitude of the cue-depreciation effect was increased when subjects were asked to adopt a passive generation approach to word fragment completion. The current study investigated an extension of Bruner and Potter's (1964) early hypothesis-generation account of the cue-depreciation effect. Findings demonstrated the influence of completion strategies for a general theory of fragment completion.

Humans↗
PubMed1995

Are anxiety symptoms in childhood heritable?

Although childhood anxiety appears to aggregate in families, transmission could be explained by both genetic and shared environmental factors. Twin studies can be used to disentangle genetic and environmental effects. In this study, a systematically ascertained sample of twins was used to investigate whether anxiety symptoms are heritable. Parent-rated anxiety symptoms could best be explained by an additive genetic model with heritability estimated at 59%. However, when self ratings were analysed (in the adolescent subsample), familial transmission could be accounted for by shared environmental factors only.

Adolescent↗
PubMed1994

The heritability of memory in the Western Reserve Twin Project.

The heritability of memory ability was examined using 137 monozygotic and 127 same-sex dizygotic twin pairs from the Western Reserve Twin Project. Memory was assessed by eight measures drawn from the following batteries: the Wechsler Intelligence Scale for Children--Revised, the Colorado Test of Specific Cognitive Abilities, and the Cognitive Abilities Test. The results indicate that phenotypic correlations are generally low across these memory measures and heritability varies as a function of memory measure. These findings suggest that the heritability of memory varies as a function of the memory measure employed. Therefore, future studies investigating heritability estimates of memory should use a multimeasure battery to study this construct.

Adolescent↗
PubMed1994

Effects of level of processing on implicit and explicit tasks.

The series of experiments presented in this article replicate the interaction that B. H. Challis and D. R. Brodbeck (1992) reported between list design (blocked or mixed) and level of processing for word fragment completion: The advantage for semantically processed words over shallowly processed words was greater when the conditions were blocked than when they were mixed on the study list. A similar interaction was found for perceptual identification (a data-driven implicit task) and priming in general knowledge questions (a conceptually driven implicit task). However, both data-driven and conceptually driven explicit tasks failed to reveal such a pattern.

Humans↗
PubMed1994

Mirror effect in frequency discrimination.

In recognition, types of stimuli that are relatively easy to classify as old when old are also relatively easy to classify as new when new. The experiments reported here extend this mirror effect to discriminations among above-zero situational frequencies. Frequency discrimination exhibits a mirror effect when words are compared with nonwords or when low-linguistic-frequency words are compared with high-linguistic-frequency words. Accurate knowledge concerning the relative memorability of test items is neither necessary nor sufficient for the presence of a mirror effect.

Humans↗
PubMed1994

Educating asthmatic patients in primary care: a pilot study of small group education.

Patient education is an important part of asthma management. Individual education is usually used for this task. The object of this study was to assess whether another educational technique, educating patients in small groups, would be as effective and as acceptable as individual counselling in improving knowledge about asthma. A specially designed questionnaire was used to assess knowledge and other variables before and after education. Thirty-four patients were educated individually and 34 patients were educated in small groups. There were significant improvements in knowledge scores after both types of education. However group education took 4.5 hours for 34 patients whereas individual counselling took 14.25 hours for the same number. The results of this study suggest that educating patients in small groups is as effective as individual counselling in improving knowledge of asthma, is acceptable to patients and takes much less time.

Adult↗
PubMed1994

The genetics of mental retardation.

Individuals affected by mental retardation are a clinically and aetiologically heterogeneous group. This heterogeneity is particularly highlighted when we consider the genetics of mental retardation. Recent advances in molecular genetic techniques have enabled us to understand more about the molecular basis of several genetic syndromes associated with mental retardation. In contrast, where there is no discrete cause, the interplay of genetic and environmental influences remains poorly understood.

Humans↗
PubMed1994

A twin study of depressive symptoms in childhood.

BACKGROUND: Although depression in childhood appears to be familial, transmission of symptoms could be genetic or environmental. Twin studies enable us to separate these effects. Our aim was to assess the importance of genetic and environmental factors on depressive symptoms during childhood and adolescence in an epidemiological sample of twins. METHOD: Questionnaires (including the Mood and Feelings questionnaire) were mailed to a systematically ascertained sample (411 twin pairs) aged between 8 and 16 years. The overall response rate was 77%. RESULTS: Data for the whole sample were best explained by an additive genetic model, with heritability of depressive symptom scores estimated at 79%. However, on splitting the sample, symptoms in children (aged 8 to 11) could be explained by shared environmental factors only, while symptoms in adolescents (aged 11 to 16) remained highly heritable. CONCLUSIONS: The results suggest that although depressive symptoms appear to be largely heritable, the influence of genetic and environmental factors may vary with age.

Adolescent↗
PubMed1993

Evidence against a short-term-store account of long-term recency effects.

When subjects perform a distractor task before and after every item on a list, recall of the last item is much higher than recall of items from the middle of the list. Koppenaal and Glanzer (1990) have shown that this long-term recency effect can be eliminated by using, after the last item, a distractor task different from that used elsewhere on the list. They interpreted this finding as evidence in favor of a short-term-store account of long-term recency effects. This account is challenged by the results reported here. Practice either on the task or on time-sharing between the task and list items had little impact on the recency effect. Also, substantial recency effects were found when a different distractor task occurred after every list position. Thus, it is not true that long-term recency effects are found only when subjects have an opportunity to adapt to the distractor task. Our results are not consistent with a short-term-store account of recency effects.

Adult↗
PubMed1992

The genetics of personality disorder.

Most measurable aspects of normal personality appear to be at least moderately heritable, with direct evidence coming from family, twin and adoption studies and indirect support deriving from psychophysiological research and breeding experiments on animals. Interestingly, genetic studies also shed light on the environmental sources of variation in personality and suggest that shared family environment rarely, if ever, has any positive effect on similarity between relatives. Despite problems of classification, and variations in the use of terms, a survey of the literature provides reasonably consistent evidence of a genetic contribution to several categories of abnormal personality, which we here divide into three groups, antisocial, anxious/avoidant, and schizoid-schizotypal personalities. However, personality disorders are complex traits that do not show simple mendelian patterns of inheritance and so far molecular genetics has been of no help in understanding their aetiology. Fortunately, techniques are now becoming available that enable the detection and potential localisation of genes of small effect and which may help elucidate the molecular basis even of (probably) polygenic traits such as abnormal personality.

Animals↗
PubMed1992

Psychological sequelae of miscarriage: a controlled study using the general health questionnaire and the hospital anxiety and depression scale.

This study was carried out to assess whether psychiatric morbidity after a miscarriage is higher than that associated with early pregnancy. A total of 60 consecutive women admitted to a Swansea hospital with a miscarriage were compared with 62 consecutive women who attended an antenatal clinic at the same hospital, using the 28-item general health questionnaire and the hospital anxiety and depression scale. These were completed both at initial contact and six weeks later. Women who had had a miscarriage were found to be significantly more anxious and scored higher on the subscale for severe depression than the pregnant women, both at initial assessment and six weeks later. At the six week assessment more somatic symptoms were also experienced by the group who had had a miscarriage. This study highlights the psychological disturbance associated with miscarriage. The primary health care team and hospital staff need to take this into consideration when organizing follow up for women who have had a miscarriage.

Abortion, Spontaneous↗