ch 9

Attention

  • Definition: Attention is the process by which certain information is selected for further processing while other information is discarded, thereby preventing sensory overload.

  • Bottleneck Model: The brain operates as a filter or bottleneck (Broadbent, 1958), as it cannot efficiently process all information it receives.

  • Inattentional Blindness: A phenomenon where individuals fail to notice an unexpected stimulus (e.g., a gorilla in a basketball game) when focused on a specific task (Simons & Chabris, 1999).

  • Change Blindness: The failure to notice changes in visual stimuli during transitions (Rensink et al., 1997).

  • Auditory Inattentional Blindness: Similar to visual inattentional blindness, individuals may fail to notice spoken words under distracting auditory environments (Dalton & Fraenkel, 2012).

Attentional Mechanisms

  • Attention is influenced by both external stimuli (bottom-up processes) and internal goals (top-down processes).

  • Spotlight Metaphor: Visual attention can be thought of as a spotlight that highlights particular locations or objects, sometimes independently of the direction of eye movement (La Berge, 1983).

    • Covert Orienting: Shifting attention without moving the eyes.

    • Overt Orienting: Moving the eyes or head to shift attention.

  • Attention limits capacity; it is possible to attend to multiple objects but attention often prioritizes salient features or locations.

Spatial and Non-Spatial Attention

  • Studies (e.g., Posner's cueing task) demonstrate that attention can be spatially oriented. Cues can aid detection at specific locations (facilitating attention) or create costs of returning attention to that location (inhibition of return).

  • Endogenous vs. Exogenous Orienting: Endogenous orienting is guided by personal goals while exogenous orienting is guided by external stimuli.

  • Object-Based Attention: Attention can be directed to individual objects regardless of their spatial location (e.g., attending to a face vs. a house presented together).

Role of the Frontoparietal Network

  • Parietal and frontal lobes are crucial for attention; the parietal lobes integrate sensory signals to create a salience map that highlights relevant stimuli.

  • Lateral Intraparietal Area (LIP): Important for spatial attention and planning saccades (eye movements). Neurons in LIP respond strongly to high salience stimuli and changes in the environment.

  • Frontal Eye Fields (FEF): Involved in voluntary eye movements and attention.