On the relations between implicit and explicit spatial binding: evidence from Balint's syndrome.

We report two experiments examining whether factors that affect binding in explicit report tasks also affect implicit binding in a patient with Balint's syndrome, G.K. Replicating prior studies, we showed that there could be implicit binding of visual features in a patient with Balint's syndrome who was at chance at explicitly discriminating the relations between the features. Nevertheless, when color-form relationships were coded, we showed that G.K.'s implicit binding, as well as his explicit report of binding relationships, was affected by the spatial distance between the stimuli. Similarly, we demonstrated effects of grouping on both implicit and explicit binding of the spatial relations between shapes. We interpret the qualitative similarities between implicit and explicit binding as indicating that they reflect a single process in which binding relations, initially established preattentively, are later consolidated by attention. This later process, of attentional consolidation, is disrupted in Balint's syndrome.