Cognition and disorders - higher perceptual functions

Question 1

Define cognition (2)

Answer 1

Processes allowing external stimuli to be perceived, processed, memorised and used to modify thoughts and actions to achieve desired goals

Question 2

Where are association cortices found? (4)

Answer 2

Frontal lobe
Temporal lobe
Parietal lobe
Occipital lobe

Question 3

What are the functions of association cortex? (5)

Answer 3

Integrate sensory and other information
Make use of past experience
Use information and experience to modify behaviour
Promotes survival
Prefrontal association cortex develops slowly

Question 4

Where does the association cortex receive input from? (11)

Answer 4

Receive input directly from other cortical areas:
- Ipsilateral cortico-cortical connections
- Interhemispheric cortico-cortical connections

Receives highly processed information from primary sensory / motor areas via thalamic nuclei:
- Pulvinar nucleus (parietal association cortex)
- Medial dorsal nucleus (frontal association cortex)
- [Anterior and ventral anterior nuclei]

Also receive subcortical inputs:
- Dopaminergic neurones in the midbrain
- Noradrenergic / serotonergic neurones in the reticular formation
- Cholinergic neurones in the brainstem and basal forebrain

Question 5

Define attention (2)

Answer 5

The state of selectively processing simultaneous sources
of information

Question 6

What does attention allow for? (4)

Answer 6

Involves preferential processing of sensory information (e.g. visual, auditory)

Allows covert shifting (e.g. listening to a conversation whilst engaged in another)

Allows shorter reaction time to stimuli (e.g. faster braking when paying attention to the car in front)

Subject to external influences (e.g. a loud noise will shift our attention away from the task at hand).

Question 7

What is attention-deficit hyperactivity disorder (ADHD)? (2)

Answer 7

Characterised by inattention, hyperactivity, impulsiveness

Imaging suggests that prefrontal cortex and basal ganglia are smaller in sufferers

Question 8

What is Contralateral neglect syndrome? (2)

Answer 8

Caused by lesion to one side of the parietal cortex, leading to the inability to attend to stimuli presented to the side of the body (or visual space) opposite the lesion

Right parietal lobe is the most common site for it.

Question 9

What is Balint’s syndrome? (3)

Answer 9

Caused by lesion to parietal and occipital cortices

Triad of visuospatial deficits:
- Simultanagnosia (inability to perceive visual scene as a whole)
- Oculomotor apraxia (difficulty in fixating the eye)
- Optic ataxia (deficit in visually guided reaching)

Question 10

Define emotion (1)

Answer 10

Composite of feelings, expressive behaviour and physiological changes

Question 11

What does generation of emotions involves? (3)

Answer 11

Evaluation of sensory input&raquo_space;> Conscious/unconscious experience of a feeling&raquo_space;> Expression of behavioural and physiological response

Question 12

What three components make an emotional response? (3)

Answer 12

Behavioural E.g. muscular movements (smile, frown etc).

Autonomic E.g. Sympathetic / parasympathetic activity

Hormonal E.g. Adrenaline release

Question 13

What are the brain systems involved in emotional processing? (4)

Answer 13

Involves “limbic system”
Clear roles for:
- Amygdala
- Orbitofrontal cortex
- Cingulate gyrus / thalamus / ventral basal ganglia

Question 14

What is speech produced by? (3)

Answer 14

Lungs (source of air)

Larynx (source of speech sounds)

Pharynx, oral cavity (incl tongue, teeth, lips) and nasal cavity (modify / filter speech).

Question 15

What is language? (2)

Answer 15

Speech of a group of people

Speech production and comprehension by the brain

Question 16

Where is language produced in the brain? (3)

Answer 16

Association cortices in left hemisphere

Broca’s area – left frontal cortex; involved in language production

Wernicke’s area – left temporal cortex; involved in understanding spoken language

Question 17

What is prosody? (1)

Answer 17

Emotional content that goes into language production and comprehension

Question 18

Where is prosody in the brain? (1)

Answer 18

Association cortices in right hemisphere

Question 19

What are disorders of language called (4)

Answer 19

Aphasias:
- Broca’s aphasia (motor or expressive aphasia)
- Wernicke’s aphasia (sensory or receptive aphasia)
- Conduction aphasia

Question 20

What are aphasias? (2)

Answer 20

Damage to specific brain regions which compromises language functions, without affecting sensory / motor processing

Question 21

What is conduction aphasia? (2)

Answer 21

Difficulty repeating words
Arise from lesions to pathways connecting language centres

Question 22

Which brain areas are responsible for executive control systems? (6)

Answer 22

Prefrontal cortex is thought to be important, alongside other cortical regions:

Dorsolateral PFC
Ventromedial PFC
Anterior cingulate cortex
Posterior parietal cortex
Basal ganglia

Question 23

Describe executive control (5)

Answer 23

Moderate the activity of other cognitive processes in a flexible and goal-directed manner

Operate rapidly and largely unconsciously to guide the flow of sensory information or to initiate motor action

Require assessing the advantages and disadvantages of different options

Measured and thoughtful processing, as when we mentally simulate an opponents strategies in a complex game

Simulation – prefrontal cortex activated when daydreaming

Question 24

What is the dorsolateral prefrontal cortex responsible for? (3)

Answer 24

Initiating and shifting behaviour (initiating and changing actions, motor movements and mental plans)

Inhibiting behaviour (suppression of unimportant or distracting information / behaviour)

Simulating behavioural consequences (creation of mental models of the world…abstraction)

Question 25

What is ventromedial prefrontal cortex responsible for? (2)

Answer 25

Inhibition of socially inappropriate behaviour (patients with lesions to this area may laugh at inappropriate times or reveal embarrassing personal information)

Sensitivity to the consequences of action (links between stimuli or action and the rewards or punishments that follow)