L'informazione numerica orienta l'attenzione visiva nello spazio: uno studio sui movimenti oculari nell'adulto [Numbers can modulate the deployment of visual attention: Evidence from an eyetracking study]

Many studies have demonstrated strong relations between numbers and oriented spatial codes, in a way that is suggestive of a spatially oriented mental representation of numbers (e.g., Dehaene, 1992; Dehaene et al., 1993). For example, perceiving numbers causes spatial shifts of attention, depending upon the numbers' magnitude (Fischer et al., 2003). The current study was aimed at investigating whether the lateralized shifts of attention induced by Arabic digits (Fischer et al., 2003) can be observed even when magnitude information is provided by non-symbolic numbers. A visual target was presented either on the left or the right side of a screen after the onset of a small-magnitude (2) or a large-magnitude (9) numerical cue, eihter symbolic (Arabic digits) or non-symbolic (arrays of dots). Using an automated eye-tracking system, we measured the time to target fixation. Results replicated earlier demonstrations that symbolic number can modulate the allocation of visuo-spatial attention, and further extend them to non-symbolic numbers represented by sets of dots.