The Involvement of Posterior Parietal Cortex in Feature and Conjunction Visuomotor Search

Abstract

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Near and far space: Understanding the neural mechanisms of spatial attention

“…Previously we demonstrated a significant Lane,18 involvement of rPPC in feature search only when an explicit motor response was required (Lane et al, 2011b), suggesting that this area is necessary for resolving spatial ambiguity to enable successful interaction with the environment. Here we find that the same brain area is necessary for purely perceptual conjunction search, meaning that there are no explicit or directional motor demands that would have otherwise explained the involvement of rPPC.…”

Effective Connectivity of the Human Cerebellum during Visual Attention

“…These regions showing this enhanced connectivity with the cerebellum where almost exclusively located in the dorsal visual stream (including V5 and PPC), which is associated with spatial localization of objects (PPC: Corradi-Dell' Acqua et al, 2008;Lane et al, 2011), motion perception (V5: Wilms et al, 2005;Orban, 2011) and spatial attention (PPC: Fan et al, 2005;Malhotra et al, 2009;Rawley and Constantinidis, 2010;Kellermann et al, 2011;Lane et al, 2012). Before we turn to the discussion of the consequential analyses of dynamic causal modeling, we briefly review some theoretical considerations regarding the functionality of the cerebellum.…”

The Premotor theory of attention: Time to move on?

“…Similarly, TMS over posterior areas (i.e. Posterior Parietal Cortex, PPC) delays saccades (Beckers et al, 1992;Muri et al, 1996;Zangemeister et al, 1995) and conjunction search (Ellison, Rushworth, & Walsh, 2003;Sack et al, 2002) but, somewhat surprisingly, does not affect feature search (Ellison et al, 2003;Muggleton et al, 2008) unless the participant is required to execute an action to the target (Lane, Smith, Schenk, & Ellison, 2011). ***FIGURE 1 HERE?…”