Disorders of Attention

Question 1

lesions in the ‘where’ stream lead to…

Answer 1

deficits in spatial attention

Question 2

patient RM had…

Answer 2

two strokes which damaged large areas of bilateral-occipito cortex

Question 3

primary impairment of balint’s syndrome

Answer 3

simultanagnosia- inability to focus attention on multiple objects

Question 4

what does simultanagnosia lead to?

Answer 4

considerable conjunction errors when seeing objects for over 10 seconds

Question 5

what is the parietal lobe important for?

Answer 5

feature binding and visual attention

Question 6

evidence of parietal lobe activity

Answer 6

• greater activity during conjunction search
• conjunction search disrupted by TMS

Question 7

hemispatial neglect

Answer 7

lack of awareness of stimuli presented to the side of space on the opposite side to the brain damage (contralesional side)

Question 8

symptoms of hemispatial neglect

Answer 8

1. deficit to attend to information in contralesional space (sensory, representational, and bodily)
2. unilateral neglect is object based rather than space based (left-hand side of all objects)

Question 9

what do hemispatial neglect patients also experience?

Answer 9

extinction deficits, suggesting different perceptual representations can locally compete for attention

Question 10

what is neglect an impairment of?

Answer 10

the bottom-up stimulus driven system

Question 11

what are neglect and extinction deficits of?

Answer 11

attention

Question 12

what are ERPs used to observe?

Answer 12

when neglect occurs in the visual stream

Question 13

what do ERPs observe in neglect patients?

Answer 13

early processing in neglect patients is similar to controls, but after 150ms there is a large difference

Question 14

what does experimental psychology show about neglect patients?

Answer 14

they fail to accurately identify objects presented to the neglected field- there is no conscious access

Question 15

priming effect in neglect patients

Answer 15

patients can be faster to respond to a semantically related word despite neglecting stimuli, suggesting meaning must be partially processed

Question 16

where is neglect seen?

Answer 16

in damage to right, inferior parietal lobe

Question 17

what does TMS produce?

Answer 17

extinction symptoms

Question 18

what do neglect patients benefit from?

Answer 18

endogenous cues in both visual fields, as top-down processing is needed to consciously pay attention to the neglected side of space

Question 19

when are neglect patients most impaired?

Answer 19

when trying to disengage attention from intact side (struggle with invalid targets failing to activate the exogenous system)

Question 20

attention in neglect patients

Answer 20

related to disengaging endogenous attention of attentional spotlight from the ipsilesional side of space, to something happening in the contralesional space

Question 21

most common neurodevelopmental disorder in children

Answer 21

ADHD, around 5%

Question 22

three subtypes of ADHD

Answer 22

1. predominantly inattentive
2. predominantly hyperactive/impulsive
3. combined inattentive and hyperactive/impulsive

Question 23

predominantly inattentive

Answer 23

difficulty in finishing tasks, following instructions, and becoming easily distracted

Question 24

predominantly hyperactive/impulsive

Answer 24

difficulty sitting still for long periods, fidgeting, and speaking at inappropriate times

Question 25

combined inattentive and hyperactive/impulsive

Answer 25

most common subtype

Question 26

what does the DSMV require for a clinical diagnosis?

Answer 26

at least 6 inattention symptoms and 6 hyperactivity/impulsivity symptoms

Question 27

when must symptoms be present?

Answer 27

before age of 12 and cause significant impairments in social and academic functioning for a clinical diagnosis

Question 28

structural impairments of ADHD

Answer 28

• 3-4% reduces cortical volume, particularly prefrontal
• reduced grey matter and cortical connectivity in fronto-parietal attention network
• reduced cortical connectivity between hemispheres

Question 29

functional impairments of ADHD

Answer 29

hypoactivity in prefrontal cortex and endogenous attention network

Question 30

molecular impairments of ADHD

Answer 30

imbalance in dopamine and noradrenaline circuits

Question 31

ADHD treatments

Answer 31

methylphenidate and dextroamphetamine

Question 32

how do ADHD treatments work?

Answer 32

facilitate release of noradrenaline and dopamine to enhance prefrontal cortex and basal ganglia availability