Get access

Cerebral correlates of visuospatial neglect: A direct cerebral stimulation study

Authors

  • Giuseppe Vallar,

    Corresponding author
    1. Dipartimento di Psicologia, Università degli Studi di Milano-Bicocca, Piazza dell'Ateneo Nuovo 1, Milano, Italy
    2. Laboratorio di Neuropsicologia, IRCCS Istituto Auxologico Italiano, Milano, Italy
    • Dipartimento di Psicologia, Università degli Studi di Milano-Bicocca, Piazza dell'Ateneo Nuovo 1–Edificio U6, Milano 20126, Italy. E-mail: giuseppe.vallar@unimib.it

    Search for more papers by this author
  • Lorenzo Bello,

    1. Neurochirurgia, Università degli Studi di Milano, Istituto Clinico Humanitas, Rozzano, Milano, Italy
    Search for more papers by this author
  • Emanuela Bricolo,

    1. Dipartimento di Psicologia, Università degli Studi di Milano-Bicocca, Piazza dell'Ateneo Nuovo 1, Milano, Italy
    Search for more papers by this author
  • Antonella Castellano,

    1. Unità Operativa di Neuroradiologia e CERMAC, Istituto Scientifico e Università Vita-Salute San Raffaele, Milano, Italy
    Search for more papers by this author
  • Alessandra Casarotti,

    1. Dipartimento di Psicologia, Università degli Studi di Milano-Bicocca, Piazza dell'Ateneo Nuovo 1, Milano, Italy
    2. Neurochirurgia, Università degli Studi di Milano, Istituto Clinico Humanitas, Rozzano, Milano, Italy
    Search for more papers by this author
  • Andrea Falini,

    1. Unità Operativa di Neuroradiologia e CERMAC, Istituto Scientifico e Università Vita-Salute San Raffaele, Milano, Italy
    Search for more papers by this author
  • Marco Riva,

    1. Neurochirurgia, Università degli Studi di Milano, Istituto Clinico Humanitas, Rozzano, Milano, Italy
    Search for more papers by this author
  • Enrica Fava,

    1. Neurochirurgia, Università degli Studi di Milano, Istituto Clinico Humanitas, Rozzano, Milano, Italy
    Search for more papers by this author
  • Costanza Papagno

    1. Dipartimento di Psicologia, Università degli Studi di Milano-Bicocca, Piazza dell'Ateneo Nuovo 1, Milano, Italy
    Search for more papers by this author

Abstract

Objective

To assess the role of the superior longitudinal fascicle, the inferior fronto-occipital fascicle, and the posterior parietal lobe in visuospatial attention in humans during awake brain surgery.

Experimental design

Seven patients with hemispheric gliomas (six in the right hemisphere) entered the study. During surgery in asleep/awake anesthesia, guided by Diffusion Tensor Imaging Fiber Tractography, visuospatial neglect was assessed during direct electrical stimulation by computerized line bisection.

Principal observations

A rightward deviation, indicating left visuospatial neglect, was induced in six of seven patients by stimulation of the parietofrontal connections, in a location consistent with the trajectory of the second branch of the superior longitudinal fascicle. Stimulation of the medial and dorsal white matter of the superior parietal lobule (corresponding to the first branch of the superior longitudinal fascicle), of the ventral and lateral white matter of the supramarginal gyrus (corresponding to the third branch of the superior longitudinal fascicle), and of the inferior occipitofrontal fasciculus, was largely ineffective. Stimulation of the superior parietal lobule (Brodmann's area 7) caused a marked rightward deviation in all of the six assessed patients, while stimulation of Brodmann's areas 5 and 19 was ineffective.

Conclusions

The parietofrontal connections of the dorso-lateral fibers of the superior longitudinal fascicle (i.e., the second branch of the fascicle), and the posterior superior parietal lobe (Brodmann's area 7) are involved in the orientation of spatial attention. Spatial neglect should be assessed systematically during awake brain surgery, particularly when the right parietal lobe may be involved by the neurosurgical procedure. Hum Brain Mapp 35:1334–1350, 2014. © 2013 Wiley Periodicals, Inc.

Get access to the full text of this article

Ancillary