I. Chris McManus

The hidden medical school: A longitudinal study of how social networks form, and how they relate to academic performance

Background: UK medical schools typically have over 300 students per year, making it impossible for students to know all the others well. Aims: This longitudinal cohort study measured the formation of medical student social networks and their relationship to grades. Method: In November 2009, 215/317 (68%) Year 2 UCL medical students reported their friendships with others in their year, by questionnaire. Multiple regression assessed the relationship between friendships, exam results and background variables (obtained from student records), with permutation testing to assess statistical significance. Results: Students of the same sex, the same ethnic group, and in the same tutor and small groups (to which they were randomly assigned at the start of medical school) were socially closer. Taking into account absolute difference in Year 1 grades, Year 2 pairs who were socially closer in November 2009 had more similar May 2010 grades. Individual student variables did not predict similarity in 2010 grades after taking friendships into account. Conclusions: The results suggest that medical students chose friends of the same sex and ethnic group as themselves; but random allocation of students to tutor groups also influenced friendships. Most importantly, friendships related to subsequent exam performance, suggesting friendship may influence learning.

Drawing on the right side of the brain: a voxel-based morphometry analysis of observational drawing

Structural brain differences in relation to expertise have been demonstrated in a number of domains including visual perception, spatial navigation, complex motor skills and musical ability. However no studies have assessed the structural differences associated with representational skills in visual art. As training artists are inclined to be a heterogeneous group in terms of their subject matter and chosen media, it was of interest to investigate whether there would be any consistent changes in neural structure in response to increasing representational drawing skill. In the current study a cohort of 44 graduate and post-graduate art students and non-art students completed drawing tasks. Scores on these tasks were then correlated with the regional grey and white matter volume in cortical and subcortical structures. An increase in grey matter density in the left anterior cerebellum and the right medial frontal gyrus was observed in relation to observational drawing ability, whereas artistic training (art students vs. non-art students) was correlated with increased grey matter density in the right precuneus. This suggests that observational drawing ability relates to changes in structures pertaining to fine motor control and procedural memory, and that artistic training in addition is associated with enhancement of structures pertaining to visual imagery. The findings corroborate the findings of small-scale fMRI studies and provide insights into the properties of the developing artistic brain.

iMAP and iMAP2 produce erroneous statistical maps of eye-movement differences

The programs iMAP and iMAP2, developed by Caldara and Miellet (2011 Behavior Research Methods 43 846–878), have attempted to implement a general approach to the analysis of eye-movement data, providing not only ‘heat maps’ of areas of greater and lesser activity but also, and potentially of great practical importance, significance tests which take into account spatial autocorrelation in fixation locations. The tests in particular allow different groups to be compared, as in one of Caldara and Miellets example datasets where fixation patterns of Western Caucasian and East Asian participants are said to be significantly different. The present paper argues that the significance tests, as implemented, used an inappropriate algorithm and therefore gave erroneous results. In particular, if participants are randomly allocated to two groups, which is a conventional randomization test, then in every case the program claimed to find ‘significant differences‘, which cannot be correct. A simple, modified statistical technique, based around a simple two-group t-test, with error functions and spatial autocorrelation taken into account, finds no differences between the example groups of participants. That conclusion is reinforced by analyzing simulated data with or without true differences, when iMAP/iMAP2 always finds significant differences, irrespective of sample size, whereas the modified method finds significant differences for only the largest sample sizes. Previous research using iMAP/iMAP2 may have come to erroneous conclusions about differences in fixation patterns between groups.

Reading and writing direction effects on the aesthetic appreciation of photographs.

ABSTRACT Does reading and writing direction (RWD) influence the aesthetic appreciation of photography? Pérez González showed that nineteenth-century Iranian and Spanish professional photographers manifest lateral biases linked to RWD in their compositions. The present study aimed to test whether a population sample showed similar biases. Photographs with left-to-right (L–R) and right-to-left (R–L) directionality were selected from Pérez González’s collections and presented in both original and mirror-reversed forms to Spanish (L–R readers) and Moroccan (R–L readers) participants. In Experiment 1, participants rated each picture for its aesthetic pleasingness. The results showed neither effects of lateral organization nor interactions with RWD. In Experiment 2, each picture and its mirror version were presented together and participants chose the one they liked better. Spaniards preferred rightward versions and Moroccans preferred leftward versions. RWD therefore affects aesthetic impressions of photography in our participants when people pay attention to the lateral spatial dimension of pictures. The observed directional aesthetic preferences were not sensitive to the sex of the model in the photographs, failing to support expectations from the hypotheses of emotionality and agency. Preferences were attributable to the interaction between general scanning strategies and scanning habits linked to RWD.

Preference for Well-Balanced Saliency in Details Cropped from Photographs

Photographic cropping is the act of selecting part of a photograph to enhance its aesthetic appearance or visual impact. It is common practice with both professional (expert) and amateur (non-expert) photographers. In a psychometric study, McManus et al. (2011b) showed that participants cropped photographs confidently and reliably. Experts tended to select details from a wider range of positions than non-experts, but other croppers did not generally prefer details that were selected by experts. It remained unclear, however, on what grounds participants selected particular details from a photograph while avoiding other details. One of the factors contributing to cropping decision may be visual saliency. Indeed, various saliency-based computer algorithms are available for the automatic cropping of photographs. However, careful experimental studies on the relation between saliency and cropping are lacking to date. In the present study, we re-analyzed the data from the studies by McManus et al. (2011a,b), focusing on statistical image properties. We calculated saliency-based measures for details selected and details avoided during cropping. As expected, we found that selected details contain regions of higher saliency than avoided details on average. Moreover, the saliency center-of-mass was closer to the geometrical center in selected details than in avoided details. Results were confirmed in an eye tracking study with the same dataset of images. Interestingly, the observed regularities in cropping behavior were less pronounced for experts than for non-experts. In summary, our results suggest that, during cropping, participants tend to select salient regions and place them in an image composition that is well-balanced with respect to the distribution of saliency. Our study contributes to the knowledge of perceptual bottom-up features that are germane to aesthetic decisions in photography and their variability in non-experts and experts.

The value of the physical examination in clinical practice: an international survey

Abstract A structured online survey was used to establish the views of 2,684 practising clinicians of all ages in multiple countries about the value of the physical examination in the contemporary practice of internal medicine. 70% felt that physical examination was ‘almost always valuable’ in acute general medical referrals. 66% of trainees felt that they were never observed by a consultant when undertaking physical examination and 31% that consultants never demonstrated their use of the physical examination to them. Auscultation for pulmonary wheezes and crackles were the two signs most likely to be rated as frequently used and useful, with the character of the jugular venous waveform most likely to be rated as infrequently used and not useful. Physicians in contemporary hospital general medical practice continue to value the contribution of the physical examination to assessment of outpatients and inpatients, but, in the opinion of trainees, teaching and demonstration could be improved.