Class_05_Attention Flashcards
Dichotic Listening Task
- Attention to sound with headphones
- Apply different sounds to each of a participant’s ears
- Attend to one ear
- Ignore another ear
Findings from Dichotic Listening Task
- Bottleneck on processing
- only the attended signal is processed deeply - Hear something important
- own name
- reorient attention to that signal
- cocktail party effect
Visual Search Task: Feature
Target has single feature that doesn’t similar to the rest
Visual Search Task: Conjunctive
Target has combined (conjunctive) features from the rest
Feature Integration Theory
Dual-process that attend to visual stimuli
1. Computationally parallel process
- every item SIMULTANEOUSLY
- Single feature
2. Computationally serial strategy
- each item AT A TIME
- Conjunctive search
Hemispatial Neglect
Hemineglect
- Ignore one side of space
- middle cerebral artery stroke
- contralesional
Left Hemispatial Neglect
- Right hemisphere middle cerebral artery stroke
- More common
- sit facing slightly to the right
- head pointing slightly to the right
- spontaneous eye movements will be mainly to the right side of space
- Auditory: locate the sound more to the right side
Right Hemispatial Neglect
- Left hemisphere middle cerebral artery stroke
- Less common
Left Hemisphere Inferior Parietal Cortex Damage
Ideomotor Apraxia
Right Hemisphere Inferior Parietal Cortex Damage
(Left) Hemispatial Neglect
Dichotic Listening Tasks in Left Hemispatial Neglect
Often only report the word given
to the right ear
5 Exteroceptive Senses
- Visual
- Auditory
- Tactile
- Olfactory
- Gustatory
Tests for Visuospatial Hemineglect
- drawing tasks
- copy simple images
- draw from memory
- clock drawing tasks
-> draw the right side of objects - cancellation
- Albert’s Line Cancellation Task
- Star Cancellation Test
-> crossed out only lines/stars on the right side of the page
Could disfunction of the attentional spotlight of Treisman and Gelade’s Feature Integration Theory be the cause of hemispatial neglect?
No.
- It’s neglected visual field
- single features that ‘pop out’ and capture attention for most people don’t appear to catch attention in patients with hemispatial neglect
Hemispatial Neglect & Representation of Objects
Left hemispatial neglect patients
1. imagine standing at a known place
- describe seeing buildings that were to their right-hand side
- neglect to describe buildings to their right
2. imagine facing the opposite direction
- described the buildings that previously neglected
Allocentric Neglect
Miss out one side of individual objects
- not the whole scene
Egocentric Neglect
Miss out parts of the drawing that are to the side of their own body midline
Allocentric Coordinates
Representations of space and position based on how objects are located relative to other objects.
Egocentric Coordinates
Representation of space and position of objects is coded relatively to the viewer’s body
Tests for Different Forms of Neglect
Apples Test
- cross out or circle all of the complete apples
Allocentric Neglect on the Apples Test
Errors
- crossing out apples that have a piece missing
Egocentric Neglect on the Apples Test
Correct
- apples with pieces missing are not circled/crossed
Error
- only apples to the one side of the page are marked
Extinction to Double Simultaneous
Stimulation
Right hemisphere inferior parietal lobe damage
- If both the left and right stimuli appear at the same time, only one appears to be attended to
- react to stimuli to their left
- react to stimuli to their right
- vision and audition
- recovered from full neglect
Causes of Neglect
- Right inferior parietal lobule damage
- Right hemisphere perisylvian damage
