Lecture 6- Attention & Neglect Flashcards
How did Posner et al. (1980) describe the function of attention?
Attention can be likened to a spotlight that enhances the efficiency of the detection of events within its beam.
What is attention in the context of cognitive processes?
Attention is the process by which some stimuli are selected for privileged processing.
Why does attention select certain stimuli over others?
The nervous system has a limited capacity and cannot process all things at all times, so stimuli compete for limited resources.
What are the two roles that attention fulfills according to cognitive psychology?
Attention is both a process (orienting/selecting/gating) and a resource (capacity).
What are four cognitive components of attention?
- Arousal- generalized sense of arousal
- Sustained attention- duration of focus, vigilance
- Selective attention
- Divided attention-Allocation of resources between different tasks
What are three components of the working model of attention? (Posner)
- Alertness: Maintains focus over time, directed by stimulus importance.
- Re(Orienting): Shifts focus, comparable to moving a flashlight’s beam; neglect indicates a failure in shifting attention.
- Executive: Mediating & monitoring interaction between top-down and bottom
up processes
What are the brain regions associated with the Alertness and Re(Orienting) component of the working model of attention?
- Alertness: RAS, Superior colliculus, Right lateralized, frontal-parietal-thalamic network, dorsal attention system
- Re(Orienting): Subcortical, frontal and parietal areas, ventral attention network
What are the two main brain areas are associated with executive control of attention (in the working model of attention)
- Lateral Prefrontal Cortex (PFC):
- detection and processing of salient stimuli= ventral PFC
- Goal-directed / working memory = dorsal PFC - Dorsal anterior cingulate
- Responsible for error monitoring/response selection
What are the roles of the Reticular Activating System in attention?
The RAS supports general alertness for attention and phasic alertness (quick response to stimuli)
What can a lesion of the RAS lead to? What can extreme arousal lead to?
A lesion can lead to coma (0 arousal), extreme arousal can impair the flexibility of attention.
What is the role of the Superior Colliculus in visual attention?
The Superior Colliculus controls the ability to visually fixate on or follow a moving stimulus through saccadic eye movements.
Which specific nuclei of the thalamus are involved in arousal and selective attention?
- Medial dorsal, reticular, and intralaminar nuclei of the thalamus are involved in arousal and vigilance,
- The pulvinar nucleus is responsible for sensory gating (selective attention)
What is the thalamus’s function in attention?
Acts as relay station for sensory and motor signals
What functions are associated with the parietal lobe in attentional processing?
The parietal lobe is essential for attentional
processing: implicated in both selection and
resource allocation.
What are the key attention-related functions of the parietal lobe?
The parietal lobe binds ‘what’ and ‘where’ information for stimuli, involved in visuospatial aspects of attention and overall attentional allocation, awarness of perceptual information
What is the function of the Superior Parietal Lobule (SPL) in attention?
The SPL is crucial for shifting spatial attention, allowing us to redirect our focus to different spatial locations.
What can damage to the IPL/TPJ cause in terms of attention?
Damage to the IPL or TPJ (temporateial junction) can result in spatial neglect, where a person ignores stimuli on one side of their body or space.
What is the function of the frontal lobe in attention?
High level, executive
control of attention,
including dividing
attention between
two tasks
What are the four different names for neglect in attentional disorders?
Heminiglect, Hemispatial neglect, Hemi-inattention, and Behavioural Inattention.
How is neglect in attentional disorders characterized?
Characterized by a failure to respond or attend to stimuli on the side opposite of a brain lesion, which cannot be explained by visual, sensory, or motor deficits.
What is a common test used to assess neglect? What will neglect patients often do during this test?
The line bisection test, where a person is asked to mark the midpoint of a line. Neglect patients will often mark the midpoint significantly off-center towards the side of space they do not neglect.
What test can show the difference in perception between a patient with neglect versus one with hemianopia?
A patient with hemianopia would detect an object when turning their head to the left, placing it in their right visual field, whereas a patient with neglect would continue to ignore the left side of space.
What are the two types of neglect demonstrated by writing and drawing tasks?
Body-centered neglect is demonstrated in a writing sample where the person starts writing from the middle of the line, ignoring the left space. Object-centered neglect is seen in a clock-drawing task where the person only draws numbers on one side.
What are body centered and object centered neglect subtypes of?
Classic unilateral neglect
