Frontoparietal cortical networks for directing attention and the eye to visual locations: identical, independent, or overlapping neural systems?

Abstract

Functional anatomical and single-unit recording studies indicate that a set of neural signals in parietal and frontal cortex mediates the covert allocation of attention to visual locations, as originally proposed by psychological studies. This frontoparietal network is the source of a location bias that interacts with extrastriate regions of the ventral visual system during object analysis to enhance visual processing. The frontoparietal network is not exclusively related to visual attention, but may coincide or overlap with regions involved in oculomotor processing. The relationship between attention and eye movement processes is discussed at the psychological, functional anatomical, and cellular level of analysis.

Figure 1

Sagittal PET section, 25 mm left of midline, of group-averaged subtraction image between shifting-attention and central-detection tasks.

Figure 2

3D rendering and 2D flattened surface of the Visible Man Brain, with the left hemisphere on the left. Lobes are indicated in 2D surface. Sulci are indicated as follows: sfs, superior frontal sulcus (s.); precs, precentral s.; cs, central s.; pocs, postcentral s.; ips, intraparietal s. Foci of activation during shifting attention [red (16), yellow (17), and orange (53)] and tonic attention [pink (24), violet (25), and light orange (Woldorff et al., unpublished data)].

Figure 3

MPrage anatomical and fMRI activity in single subject during shifting attention in left visual field. Transverse section, z = 52. Coronal sections along precentral (precs), postcentral (pocs), and intraparietal sulcus (ips).

Figure 4

Visible Man Brain as in Fig. 2. Foci for saccadic eye movements.

Figure 5

Visible Man Brain as in Fig. 2. Foci for attention from Fig. 2 (red) and eye movement from Fig. 4 (green). Areas of overlap are in yellow.

Figure 6

Anatomical MRI and fMRI activity in single subject for shifting attention and saccadic eye movements in left (LVF) and right (RVF) hemispheres. Slices at z = 52 mm.