Studies of the visual capacity of neurological patients have provided evidence for a dissociation between the perceptual report of a visual stimulus and the ability to direct spatially accurate movements toward that stimulus. Some patients with damage to the parietal lobe, for example, are unable to reach accurately towards visual targets that they unequivocally report seeing. Conversely, some patients with extensive damage to primary visual cortex can make accurate pointing movements or saccades toward a stimulus presented in their 'blind' scotoma. But in investigations of visuomotor control in patients with visual disorders, little consideration has been given to complex acts such as manual prehension. Grasping a three-dimensional object requires knowledge not only of the object's spatial location, but also of its form, orientation and size. We have examined a patient with a profound disorder in the perception of such object qualities. Our quantitative analyses demonstrate strikingly accurate guidance of hand and finger movements directed at the very objects whose qualities she fails to perceive. These data suggest that the neural substrates for the visual perception of object qualities such as shape, orientation and size are distinct from those underlying the use of those qualities in the control of manual skills.

Speech and language-related functions tend to depend on the left hemisphere more than the right in most right-handed (dextral) participants. This relationship is less clear in non-right handed (adextral) people, resulting in surprisingly polarized opinion on whether or not they are as lateralized as right handers. The present analysis investigates this issue by largely ignoring methodological differences between the different neuroscientific approaches to language lateralization, as well as discrepancies in how dextral and adextral participants were recruited or defined. Here we evaluate the tendency for dextrals to be more left hemisphere dominant than adextrals, using random effects meta analyses. In spite of several limitations, including sample size (in the adextrals in particular), missing details on proportions of groups who show directional effects in many experiments, and so on, the different paradigms all point to proportionally increased left hemispheric dominance in the dextrals. These results are analyzed in light of the theoretical importance of these subtle differences for understanding the cognitive neuroscience of language, as well as the unusual asymmetry in most adextrals.

Most football players and coaches agree that players are capable of learning to use both feet with equal frequency and efficiency--that is, become 'two-footed'. There is also some consensus that two-footed play is associated with skill in individual players. If these assumptions are true, then the world's elite football players should be substantially less 'one-footed' than the rest of the population. To examine this issue, we quantified the pattern of foot use in a sample of 236 players from 16 teams in the 1998 World Cup (France '98). Our findings indicate that World Cup players are as right-footed as the general population (approximately 79%). The remaining players were largely left-footed and as biased towards the use of their preferred foot as their right-footed counterparts. Very few players used each foot with equal frequency. Remarkably, both left- and right-footed players were as skilled, on average, with their non-preferred foot as they were with their preferred foot, on the rare occasions when they used it. Therefore, it is unlikely that infrequent use of one foot compared to the other foot can be accounted for by skill differences between the feet. Players were most asymmetrical for set pieces; nevertheless, first touches, passes, dribbles and tackles were rarely performed with the non-preferred foot as well. Our results support a biological model of foot preference and performance, as well as demonstrating the usefulness of soccer for studies of lateral asymmetries.

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