Article

Patients with imagery neglect (RI+) show peculiar difficulties in orienting
themselves in the environment. Navigational impairments could be due to a deficit
in creating or using a mental representation of the environment (Guariglia,
Piccardi, Iaria, Nico, & Pizzamiglio, 2005) or, according to the BBB model
(Burgess, Becker, King, & O'Keefe, 2001), to a specific deficit in a mechanism
that transforms an allocentric representation into an egocentric one and vice
versa. Previous studies, however, do not allow discerning between a deficit in
forming or in using a cognitive map, taking no notice of the fact that these are
two different abilities underlain by different neuroanatomical areas, which could
be independently impaired. Furthermore, the BBB model has never been verified in
a population of brain-damaged patients. Therefore, we administered two tasks that
separately assess the ability to create and use a cognitive map of the
environment to 28 right brain-damaged patients (4 patients with imagery neglect
and 4 patients with perceptual neglect) and 11 healthy participants. RI+ patients
showed no specific deficit in creating or using a cognitive map, but failed to
transform an egocentric representation of the environment into an allocentric one
and vice versa, as predicted by the BBB model.
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Langue : ANGLAIS