Levels of Sensory Processing

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Attention!! fMRI images of a subject cued to expect a stimulus in a particular portion of the visual field show right hemisphere activation in the cingulate cortex.

What is attention?? Traditional information processing views: Based on limits to simultaneous processing. Mechanisms exist to filter, gate, select or inhibit. Prevailing view for years: Bottleneck A basic conversion from massive parallel input to a limited or serial processing mode.

Sequel to information processing: Hi degree of parallel processing Flexible allocation of resources Attention interacts with motor output.

Along came Posner and Boies Attention is not a unitary phenomenon. Alertness or Readiness to take in information (concentration, vigilence) Selective Attention – search a display or an environment for a particular target. A. SPATIAL ATTENTION (3 components). Covert and overt.

“Attentional Stimuli” Are responded to more rapidly Give rise to an increase or a decrease in neuronal responses Have signature ERPs (P300, N200, N400) Can be reported with a lower threshold of occurence Will be remembered better

Attentional Stimuli - continued Increased learning of the stimulus A bias to respond to that stimulus Note – many behavioral indications involve change in accuracy and latency. The pattern of change is taken as an indication of attention or NOT.

Impaired Response Inhibition Stroop

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