Brigida Fierro
Research Subjects
Brigida Fierro has a total of 6 co-authors. Here are the top co-authors by number of shared publications:
Aurelio Piazza
Neurophysiological Unit
1 shared publicationEdoardo Bisiach
Department of Psychology, University of Torino, Italy
1 shared publication- Filippo Brighina
Department of Biomedicine, Neuroscience and Advanced Diagnostics (BIND), University of Palermo, 90127 Palermo, Italy
1 shared publication Massimiliano Oliveri
1 shared publicationOrnella Daniele
Neurophysiological Unit
1 shared publicationVincenzo La Bua
Neurophysiological Unit
1 shared publication
Latest Publications
- 1 December 2002
- Published by Wolters Kluwer Health in NeuroReport
- Vol. 13 (18) , 2571-2575
Perceptual and response bias in visuospatial neglect due to frontal and parietal repetitive transcranial magnetic stimulation in normal subjects
Recently some authors have challenged the conventional association of directional motor neglect with damage of frontal structures, showing that pure sensory perceptual neglect (classically associated with parietal lesion) can follow damage of right frontal cortex. The aim of the present study was to assess the type of defect in visuo-spatial attention consequent upon a virtual frontal or parietal lesion induced by transcranial magnetic stimulation in normal subjects. To this purpose eleven subjects performed a visuo-spatial task requiring judgement about the length of the two segments of asymmetrically bisected horizontal lines, presented for 50 ms on a computer monitor. After each visual stimulus, subjects made a binary forced choice decision according to two different response conditions: A and B. In condition A, they had to name (right or left) the longer segment and in B the shorter segment of the line. The task was given in baseline condition and during repetitive transcranial magnetic stimulation. Trains of 10 stimuli at 25 Hz of frequency were applied over right frontal premotor and right posterior parietal areas, synchronously with visual stimuli. Parietal and frontal magnetic stimulation gave rise to significant perceptual bias as compared to baseline performance (i.e. subjects made opposite errors in the two response conditions). No significant response bias (i.e. the tendency to name the same side of the line in the two response conditions) was induced by magnetic stimulation on parietal and frontal sites. The present study highlights both the relevant contribution of frontal cortex in the determinism of neglect and the predominant role of sensory perceptual factors in parietal and frontal neglect.
- 1 December 2002
- Published by Wolters Kluwer Health in NeuroReport
- Vol. 13 (18) , 2571-2575
Perceptual and response bias in visuospatial neglect due to frontal and parietal repetitive transcranial magnetic stimulation in normal subjects
Recently some authors have challenged the conventional association of directional motor neglect with damage of frontal structures, showing that pure sensory perceptual neglect (classically associated with parietal lesion) can follow damage of right frontal cortex. The aim of the present study was to assess the type of defect in visuo-spatial attention consequent upon a virtual frontal or parietal lesion induced by transcranial magnetic stimulation in normal subjects. To this purpose eleven subjects performed a visuo-spatial task requiring judgement about the length of the two segments of asymmetrically bisected horizontal lines, presented for 50 ms on a computer monitor. After each visual stimulus, subjects made a binary forced choice decision according to two different response conditions: A and B. In condition A, they had to name (right or left) the longer segment and in B the shorter segment of the line. The task was given in baseline condition and during repetitive transcranial magnetic stimulation. Trains of 10 stimuli at 25 Hz of frequency were applied over right frontal premotor and right posterior parietal areas, synchronously with visual stimuli. Parietal and frontal magnetic stimulation gave rise to significant perceptual bias as compared to baseline performance (i.e. subjects made opposite errors in the two response conditions). No significant response bias (i.e. the tendency to name the same side of the line in the two response conditions) was induced by magnetic stimulation on parietal and frontal sites. The present study highlights both the relevant contribution of frontal cortex in the determinism of neglect and the predominant role of sensory perceptual factors in parietal and frontal neglect.