Higher Cognative Functions Flashcards
What is cognition?
This is the faculty of knowing
Processes allowing external stimuli to be perceived, processed, memorised and used to modify thoughts and actions to achieve desired goals
Many explanations for behaviours are based on survival/evolutionary theory
What are association cortices?
There are association cortices in the frontal, parietal, occipital and temporal lobes
They are found in most of the cerebral cortex except primary, sensory and motor areas
Role:
They integrate sensory and other information
Make use of past experience
Use information and experience to modify behaviour
Promotes survival
Prefrontal association cortex develops slowly
Where do association corices receive information?
They receive information from other cortical areas
○ Ipsilateral cortico-cortical connections
○ Interhemispheric cortico-cortical connections
They receive 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]
They can receive subcortical inputs
○ Dopaminergic neurones in the midbrain
○ Noradrenergic / serotonergic neurones in the reticular formation
○ Cholinergic neurones in the brainstem and basal forebrain
What is attention?
The state of selectively processing simultaneous sources of information
This involved preferential processing of sensory information
Allows for covert shifting within senses
Allows increased reaction time to stimuli
Subject to external influences
What brain systems are involved in attention? Evidence?
Mainly by the right parietal cortex
Also evidence for prefrontal cortex and basal ganglia
Evidence comes from clinical observations of disorders of attention such as:
Attention-deficit hyperactivity disorder
Contralateral neglect syndrome (failure to attend to stimuli presented to the side of the body)
Balint’s syndrome (one symptom is simultanagnosia - inability to perceive visual scene as a whole)
What is emotional processing?
Hard to study or define
Comprised of feelings, expressive behaviour and physiological changes
Generation of emotions involves:
○ Evaluation of sensory input
○ Conscious/unconscious experience of a feeling
○ Expression of behavioural and physiological response
What does an emotional response consist of?
An emotional response consists of three components:
Behavioural - muscular movements (smile, frown etc)
Autonomic - sympathetic/parasympathetic activity
Hormonal - Adrenaline release
What brain systems are involved in emotional processing?
Involves the limbic system - with roles for: amygdala, orbitofrontal cortex
Amygdala:
1. recognizes fear in facial expressions;
2. recognizes multiple emotions in a single facial expression;
3. but is not required to recognize personal identity from faces
Therefore passively recognising fear (emotion) in faces
Define speech and language?
Speech produced by:
Lungs (source of air)
Larynx (source of speech sounds)
Pharynx, oral cavity and nasal cavity
Language:
Speech of a group of people
Speech production and comprehension by the brain
What brain systems are involved in speech and language?
Language is both localised and lateralised
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
Association cortices in right hemisphere - prosody
What are some disorders of language?
Aphasias – damage to specific brain regions which compromises language functions, without affecting sensory/motor processing
Broca’s aphasia (motor or expressive aphasia)
Wernicke’s aphasia (sensory or receptive aphasia)
Conduction aphasia – difficulty repeating words (due to lesions in pathways)
What are executive control systems?
The brain is constantly overseeing many complex activities and must be prepared to make decisions, through reasoning and problem solving
The pathways that the executive control carries out:
Planning, sequence, monitoring and feedback
What are important regions of the brain for executive control?
Mainly the prefrontal cortex Dorsolateral PFC Ventromedial PFC Anterior cingulate cortex Posterior parietal cortex Basal ganglia
What is the function of the executive control systems?
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
What is the prefrontal cortex vital for?
Essential for many aspects of our personality
Dorsolateral prefrontal cortex
Initiating and shifting behaviour
Inhibiting behaviour
Simulating behavioural consequences
Ventromedial prefrontal cortex
Inhibition of socially inappropriate behaviour
Sensitivity to the consequences of action
