Biomedical subjects

Martin J Tovée

Publications and source records attributed to Martin J Tovée.

6 recordsLinked to original sources

PubMed2006

Does hunger influence judgments of female physical attractiveness?

To account for male preferences for female body weight following a consistent socio-economic pattern, Nelson and Morrison (2005) proposed a social-cognitive model based on the individual experience of resource scarcity. We replicated their studies showing that calorific dissatisfaction can influence preference for female body weight using a different dependent variable, namely photographic stimuli of women with known body weight and shape. Using this revised methodology, we found that operationalized intra-individual resource scarcity affects preferences for body weight: 30 hungry male participants preferred figures with a higher body weight and rated as more attractive heavier figures than 31 satiated male participants. Hungrier men were also less likely to be influenced by cues for body shape, supporting extant cross-cultural studies on female physical attractiveness. These findings corroborate those of Nelson and Morrison (2005) and are discussed in terms of how cultural contexts shape individual psychological experience as predicted by the theory of mutual constitution.

Adult↗

PubMed2004

Pentagon drawing and neuropsychological performance in Dementia with Lewy Bodies, Alzheimer's disease, Parkinson's disease and Parkinson's disease with dementia.

OBJECTIVES: Early and accurate diagnosis of Dementia with Lewy Bodies (DLB) to allow the appropriate clinical treatment is a priority, given reports of severe neuroleptic sensitivity and a preferential response to cholinesterase inhibitors in these patients. There have been suggestions that constructional apraxia is prevalent in DLB, and may provide a sensitive marker of the disease. METHODS: This study examined the pentagon drawings of 100 DLB patients, 50 Alzheimer's disease (AD) patients, 81 Parkinson's disease (PD) patients of whom 36 suffered from dementia (PDD). Performance on this task was correlated with cognitive performance on the MMSE and CAMCOG scales. RESULTS: Patients with DLB were found to draw significantly worse pentagons than those with AD or PD, but not those with PDD. Drawing scores were significantly correlated with MMSE scores for the AD and PDD groups but not those with DLB. More detailed analysis of the neuropsychological correlates of constructional performance for patients with AD and DLB, revealed that those with AD showed a broad cognitive basis to their impairment, in DLB drawing was linked only to perception and praxis. CONCLUSIONS: This study has suggests that DLB subjects show an impairment of pentagon copying that is dissociable from more global cognitive impairments, whereas PD patients are relatively unimpaired on pentagon copying and AD and PDD patients show a linkage of their impairment in copying with more global cognitive deficits.

Aged↗

PubMed2004

A failure of 'pop-out' in visual search tasks in dementia with Lewy Bodies as compared to Alzheimer's and Parkinson's disease.

OBJECTIVES: The pattern of neural damage in dementia with Lewy Bodies (DLB) led us to hypothesize that patients with DLB would be particularly impaired on parallel ('pop-out') search tasks, relative to serial search tasks, and that this would serve to distinguish DLB from other forms of neurodegenerative disease, particularly Alzheimer's disease (AD). METHODS: To explore this possibility we tested four groups of observers (DLB, Alzheimer's Disease, Parkinson's Disease and age-matched controls) on parallel and serial search tasks, and a choice reaction time task. RESULTS: The DLB participants performed in a quantitatively and qualitatively different manner to the other groups. As predicted, they were particularly impaired on the parallel search task relative to the other observer groups. CONCLUSIONS: This pattern of deficit may reflect damage in the occipital areas leading to deficits in figure-ground segregation, and can assist differential diagnosis of DLB from other patients groups such as AD.

Aged↗

PubMed2003

Correlations, feature-binding and population coding in primary visual cortex.

To test the hypothesis that correlated neuronal activity serves as the neuronal code for visual feature binding, we applied information theory techniques to multiunit activity recorded from pairs of V1 recording sites in anaesthetised cats while presenting either single or separate bar stimuli. We quantified the roles of firing rates of individual channels and of cross-correlations between recording sites in encoding of visual information. Between 89 and 96% of the information was carried by firing rates; correlations contributed 4-11% extra information. The distribution across the population of either correlation strength or correlation information did not co-vary systematically with changes in perception predicted by Gestalt psychology. These results suggest that firing rates, rather than correlations, are the main element of the population code for feature binding in primary visual cortex.

Action Potentials↗

PubMed2003

Measurement of body size and shape perception in eating-disordered and control observers using body-shape software.

A disturbance in the perception of personal body size and shape is a key feature of both anorexia and bulimia nervosa, but it has proved difficult to quantify. Previous attempts have used methods like the distorting video technique (DVT), which alters an image by stretching the figure in either the X- or Y-axis. This is a poor representation of the way fat is added to or lost from the body, and the pattern of distortion provides a host of cues to the degree to which the image has been altered. To overcome these problems we have used a specially designed software system that uses biometric data based on real body shapes, instead of simply stretching or compressing images of bodies. This technique also allows individual body parts to be altered separately, so we can determine whether a specific body part is overestimated relative to others. We can also calculate the apparent body mass index (BMI) of our modified pictures, using the perimeter-area ratio (PAR). This allows us to compare an observer's actual BMI with that calculated for their estimated and ideal bodies. We tested 30 anorexic, 30 bulimic and 137 control observers. Our results show that all three observer groups tend to overestimate their body size, but not significantly so. Both the control and bulimic observers prefer an ideal body with a BMI of 20, which is at the lower end of the 'normal' BMI range. However, the anorexics ideal BMI is 15, which is on the border between the emaciated and underweight BMI categories.

Adult↗

PubMed2002

Human female attractiveness: waveform analysis of body shape.

Two putative cues to female physical attractiveness are body mass index (BMI) and shape (particularly the waist-hip ratio or WHR). To determine the relative importance of these cues we asked 23 male and 23 female undergraduates to rate a set of 60 pictures of real women's bodies in front-view for attractiveness. In our set of images, the relative ranges of BMI and WHR favoured WHR. We based these ranges on a sample of 457 women. We did not limit the WHR range, although we kept the BMI range to 0.5 s.d. either side of the sample means. As a result, WHR averaged 1.65 s.d. either side of its sample mean. However, even with these advantages, WHR was less important than BMI as a predictor of attractiveness ratings for bodies. BMI is far more strongly correlated with ratings of attractiveness than WHR (BMI approximately 0.5, WHR approximately 0.2). To further explore the relative importance of BMI and WHR, we deliberately chose a subset of these images that demonstrated an inverse correlation of BMI and WHR (i.e. a group in which as images get heavier they also become more curvaceous). If WHR is the most important determinant of attractiveness, then the more curvaceous (but higher BMI) images should be judged most attractive. However, if BMI is a better predictor, then the opposite should be true. We found that the more curvaceous (but higher BMI) images were judged least attractive, thereby inverting the expected rating pattern. This strongly suggests that viewers' judgements were influenced more by BMI than WHR. Finally, it is possible that body shape is an important cue to attractiveness, but that simple ratios (such as WHR) are not adequately capturing it. Therefore, we treated the outline of the torso as a waveform and carried out a set of waveform analyses on it to allow us to quantify body shape and correlate it with attractiveness. The waveform analyses address the complexity of the whole torso shape, and reveal innate properties of the torso shape and not shape elements based on prior decisions about arbitrary physical features. Our analyses decompose the waveform into objective quantified elements whose importance in predicting attractiveness can then be tested. All of the components that were good descriptors of body shape were weakly correlated with attractiveness. Our results suggest that BMI is a stronger predictor of attractiveness than WHR.

Adult↗