Brain Regions Involved in Attention and Consciousness

Brain Regions Involved in Attention

Brain Regions Responsible for Shifts in Attention

• Superior Colliculus
  • Controls eye movement toward objects of attention.
  • Helps direct covert attention.
• Pulvinar Nucleus
  • Located in the posterior region of the thalamus.
  • Important for orienting, shifting attention, and inhibiting stimuli.
  • More distractors lead to greater activation of this region.

Generating and Directing Attention

• Two major pathways involved in selecting and shifting attention:
  • Dorsal Frontoparietal Pathway:
  • Involves top-down (voluntary) attention.
  • Right Temporoparietal Pathway:
  • Involves bottom-up (reflexive) attention.

Dorsal Frontoparietal Pathway: Top-Down Control (Voluntary)

• Intraparietal Sulcus (IPS)
  • Neurons increase firing rate when attention is directed towards specific stimuli (visual or auditory).
  • Plays a critical role in steering attention.
  • Damage here makes voluntary shifts of attention difficult.
• Frontal Eye Field (FEF)
  • Damage results in inability to ignore distractors in the periphery.
  • Crucial for directing gaze towards stimuli based on cognitive goals (top-down processing).

Right Temporoparietal Pathway: Bottom-Up Control (Reflexive)

• Temporoparietal Junction (TPJ)
  • Located at the intersection of the temporal and parietal lobes in the right hemisphere.
  • Directs attention towards new or unexpected stimuli (e.g., flashes, color changes).
  • Neural activity spikes in this region regardless of where the stimuli occur in the visual field.
  • Receives direct input from the visual cortex.

Brain Disorders & Attention

Hemispatial Neglect

• A condition where individuals ignore stimuli on the left side of their midline.
• Patients typically have normal vision but may neglect people and objects on the affected side.
• Associated with lesions in the frontoparietal attention network.

Bálint’s Syndrome

• Characterized by bilateral damage to the parietal lobe.
• Symptoms include:
  • Oculomotor Apraxia: Difficulty directing visual gaze horizontally.
  • Optic Ataxia: Inability to reach for objects using visual cues.
  • Simultagnosia: Inability to perceive more than one object or feature simultaneously.

Consciousness

Attention and Consciousness

• What is Consciousness?
  • According to William James, "My experience is what I agree to attend to. Only those items of which I notice shape my mind - without selective interest, experience is an utter chaos."
• Definition of Consciousness:
  • The state of being aware of our own conscious experiences and the perception of our thoughts and surroundings.
• Brain Regions Implicated:
  • Default Mode Network: Active during quiet introspective thought, involving frontal, parietal, and temporal regions.
  • Claustrum: A sheet of neurons in the forebrain, lateral to the basal ganglia.

Elements of Consciousness

• Theory of Mind: Understanding that others have their own beliefs, knowledge, and desires.
• Mirror Recognition: Recognition of the self as depicted in the mirror.
• Imitation: The ability to copy others' actions, significant for empathy and self-awareness.

More Elements of Consciousness

• Empathy & Emotion: Imagining the feelings of others.
• Tool Use: Utilizing objects to achieve specific goals.
• Language: Employing a system of arbitrary symbols to convey information with specific meanings and grammar.
• Metacognition: The ability to think about one's own thinking processes.

Planning and Monitoring Behavior

• Executive Functions: Higher-level cognitive processes that control and organize thoughts, behaviors, and feelings. Functions include:
  • Task switching
  • Working memory
  • Inhibition of thoughts/behaviors
  • Thought suppression
  • Monitoring ongoing performance.
• Delay of Gratification: An example of the executive function process.
• Important Brain Region: Prefrontal cortex, relevant to working memory and task switching.