The present study examined the relations between the lesions linked to visual and tactile extinction (VE and TE), and those related to visual field defects and spatial neglect. Continuous variations in patients' performance were used to assess the link between behavioural scores and integrity of both grey and white matter (GM and WM). We found both common and distinct neural substrates associated with extinction and neglect. Damage to angular and middle occipital gyri, superior temporal sulcus (STS) and insula were linked to VE. Lesions involving the supramarginal gyrus (SMG), intraparietal sulcus, middle frontal and superior temporal gyri (MFG and STG) were associated exclusively with spatial neglect. Lesions affecting the temporo-parietal junction (TPJ), the middle temporal region, middle frontal area (BA46) as well as the insula and putamen were linked to both spatial neglect and VE. Analysis of the relations between VE and TE highlighted the TPJ as the common site for both modalities. These findings suggest that the TPJ plays a general role in identifying salient events in the sensory environment across multiple modalities. Furthermore, WM analyses pointed to superior longitudinal fasciculus (SLF) as critical for interconnecting components of the visuospatial attention network. We demonstrated that functional disconnections resulting from SLF damage contribute to altered performance on attention tasks measuring not only neglect but also VE and TE. We propose that the SLF supports interactions between functionally specialized regions involved in attentional control across multiple sensory modalities.
Bibliographical noteFunding Information:
The authors would like to thank Dr Mohamed L. Seghier from Wellcome Trust Centre for Neuroimaging (Institute Of Neurology, UCL, London, UK) for providing us with his Matlab codes for modified unified segmentation and an outlier detection algorithm. This work was supported by grants from the Coventry and Warwickshire Partnership NHS Trust (MC and SD), Leverhulme Trust (PR), the MRC and the Stroke Association (GWH).
- Temporo-parietal junction
- Voxel-based morphometry
ASJC Scopus subject areas
- Neuropsychology and Physiological Psychology
- Experimental and Cognitive Psychology
- Cognitive Neuroscience