Visual orienting, learning and conscious awareness

Testing the dorsal stream attention hypothesis: Electrophysiological correlates and the effects of ventral stream damage

“…This hypothesis predicts that dorsal stream structures should be activated when participants encode peripheral objects that serve as cues for an attention movement. The activations illustrated in Figures 4a and 5a Although the behavioural effects of presenting bilateral letter cues to participants in a spatial attention procedure are now well documented (Lambert, 2003;Lambert & Duddy, 2002;Lambert & Holmes, 2004;Lambert, Norris, Naikar, & Aitken, 2000;Lambert, Roser, Wells, & Heffer, 2006;Lambert & Shin, 2010;Shin, Marrett & Lambert, 2011) this is the first study to probe the electrophysiological sequelae of bilateral peripheral cues. Results from the experiment show that in two important respects, the electrophysiological correlates of bilateral peripheral cues show close correspondence with effects reported in earlier studies of spatial cueing using both central and peripherally presented cues (Anllo-Vento et al, 2004;Doallo et al, 2004;He et al, 2008;Praamstra & Kourtis, 2010).…”

“…Experiment 2 seeks to test the causal implications of these EEG correlates by exploring performance on these tasks in a patient (DF) who has a bilateral lesion to her ventral stream that severely impairs form perception. If the differences seen in the dorsal and ventral streams in Experiment 1 truly reflect the differential causal involvement of these streams in each of these tasks, then one should expect the Perception Procedure but not the Attention Procedure to be disrupted in this et al, 2003;Malach, 1995).…”

Response-Dependent Contributions of Human Primary Motor Cortex and Angular Gyrus to Manual and Perceptual Sequence Learning

“…The angular gyrus had a critical role in perceptual but not manual sequence learning In the perceptual cTBS M1 and control conditions, rapid-occurring within 100 ms of a predictive cue (Lambert, 2003)-and sustained covert reorienting of visuospatial attention rather than action supported probabilistic sequence learning. Perceptual knowledge was expressed through the conscious generation and recognition of the trained sequence.…”

Can the exploration of left space be induced implicitly in unilateral neglect?

“…Although endogenous orienting is often viewed as a controlled process based on the strategic allocation of attention, some studies have challenged this conception, demonstrating that endogenous orienting processes can sometimes be independent of consciousness or verbal report Lambert, 2003;Lambert et al, 1999;Risko & Stolz, 2010). The possibility that implicit orienting processes might be preserved in neglect patients, and that these processes could be used to help patients respond to stimuli presented to their contralesional side, has not previously been studied.…”

“…The conclusion that these cueing effects were the result of motivated strategic considerations or expectancies could thus be challenged. In fact, some authors have questioned the purely explicit and "controlled" nature of endogenous attentional orienting Lambert, 2003;Lambert, Naikar, McLachlan, & Aitken, 1999;Lopez-Ramon et al, 2011;Risko & Stolz, 2010). To better understand the phenomenology of endogenous orienting in healthy subjects, used a Posner procedure but manipulated the information given to the participants before the testing session: half were informed of the cue-target relation, and the other half were not.…”