Attention: Select what info to process and what to ignore.

• Inattentional Blindness: Unable to perceive outside the spotlight.

  E.g. Missing a chicken in the background of a jump rope scene

• Change-Blindness: Inability to detect changes to a scene.

  E.g. Unable to detect that someone has changed their ties.

  Bottleneck: Brain has insufficient resources to process too much info.

• Inattentional Deafness: Cannot hear a tone when processing a high-load task.

Selective Attention

Selective Attention: Pay attention to one thing at the expense of all others.

• Cocktail Party Effect: Ability to pay attention to one person in a crowded environment.
• Dichotic Listening Task: Subjects listen to recordings of different conversations in left/right ear. Task: Repeat words from the attended ear and ignore the unattended ear. Test ability to remember info from the unattended ear.
  • Attended Message: The message that the subject focuses on.
  • Unattended Message: The message that the subject ignores.
  • Shadowing: Repeating attended message.
  • Results: Subjects cannot remember anything or notice change in the unattended message.

When is information filtered?

Broadbent's Filter Model: Input → Sensory Memory → Filter → Detector → Long-term Memory

• Detector: Processor of information's meanings.
• Early Selection Model: Meaning is processed after the filter.
• Not supported by research

Late Selection Model: Meaning is processed before filter.

• Research - Unattended channel's meaning is processed if they heard their name in it.
• Research - Can focus on one sentence continued in alternating ears.

Attenuator Theory (Triesman): Filters based on physical properties but some info crosses the filter with reduced strength. Meaning is processed if it matches high-priority words or context.

• Input → Attenuator → Dictionary Unit → Memory
• Relatively early selection.

Late Filter Theory: Attentional filter is much more flexible (movable filter).