Lateralization of spatial attention: Evidence from line bisections by football officials

The healthy brain shows a hemispheric lateralization biasing attention to the left hemifield, a phenomenon known as pseudoneglect. It is currently still not clear whether this bias can be modulated by training. Football officials represent an ideal population for investigating training effects on spatial attention, given that referees deploy attention across the field in all directions, whereas assistant referees monitor the guidelines back and forth only and allocate attention mostly to the left direction. Here, we assessed attentional biases from referees and assistants by administering a standard line bisection task. Results documented individual differences in bisection errors, with a prevalence, as expected, of errors signalling left attentional biases (i.e., pseudoneglect). Interestingly, this left bias decreased as a function of months of expertise for the referees group, whilst it remained essentially constant for the assistants group. This finding represents evidence that prolonged training in allocating attention to both visual hemifields can counteract the left attentional bias typical of most individuals.