L2 - Cognition & Neuroscience Flashcards
What do the frontal lobes do?
Diverse funcs:
- Motor control
- Language
- Cognitive control such as planning, controlling and regulating the flow of info processing, EXECUTIVE FUNCTIONING.
What does the prefrontal cortex do?
COGNITIVE CONTROL
- human size of PFC makes us unique
- processes essential for goal-oriented behaviour
- Planning based on past experience
- Adaptive to environment
- Alter behaviour to achieve goals (performance monitoring and correction)
- Regulation of info processing across brain
- Hierarchical processing
Principles of subdivision?
- 6 neocortex layers, subdivided architectonically based on distribution of different cell fibres.
- subdivided based on thalamic connections
- subdivided based on func properties, primary, secondary and association areas.
What are brodmann’s areas (BA)?
Area 6&8: Premotor cortex and Supplementary Motor Area (SMA) - planning - sequences of movements
Area 9, 46, 45, 47: Dorso Lateral Prefrontal Cortex - important in working memory and cognitive control
Area 10: Frontal Pole: Least understood, important in planning, organisation and anticipation
Area 11 & 47: Orbitofrontal Cortex - important in inhibition, downregulating behaviours, often damaged in motor accidents due to bony skull.
Area 44: Broca’s Area - speech, usually left side.
Area 4: Motor Cortex (M1) - homonculus map of human body superimposed onto it.
what do thalamic connections achieve?
cognitive control
Describe thalamic connections
Efferent Connections - to the thalamus, down to control actions
Afferent connections -
sensory, introceptive info, emotional states. Info goes up to the cortical mantle, but not all of it reaches consciousness. There is a down reg of irrelevant info to focus on tasks –> Attentive switching.
What is Luria’s Model?
Luria’s Working Brain
three principal functional units of the brain whose participation is necessary for any type of mental activity.
PRIMARY ZONE receives impulses from or sends impulses to the periphery - Eg. Motor cortex, Auditory Cortex, topological organisation, execution of movement.
SECONDARY ZONE processes incoming information and programs information for projection to efferent pathways - Eg. Premotor cortex, organisation of movement informed by tertiary zones.
TERTIARY ZONE is the last to develop and is responsible for complex forms of mental activity which requires the integrated participation of many cortical structures.
- Prefrontal Cortex, planning goal directed activities, self regulation and monitoring, cortical alertness, and is not fully myelinated until late adolescence.
What is Luria’s Brain-Behaviour Theory?
There are 3 basic units of the CNS.
- Reg of arousal and muscle tone by BRAINSTEM and associatied areas - BASIC life support funcs, HR, Alertness, respiration.
if brainstem is injured –> coma - Reception, integration and analysis of sensory information - POSTERIOR CORTICAL REGIONS
- Planning, executing and verifying behaviour - frontal and PFC. - to achieve goals
Difference between frontal lobotomy and leucotomy?
Frontal lobotomy is removing a lobe, and leucotomy is transorbital cutting of fibres.
they both created cog control problems
psychosurgery
What is trasorbital lobotomy and its side effects?
severing of fibres at base of frontal lobes, as treatment for psychiatric symptoms and innappropriate behaviour (mostly scz).
- under 10 mins
- side effects were blunting of affect, apathy, impulsiveness, lack of motivation and social disinhibition.
basically severed white matter, thalamic connections
What is an example of a closed head injury?
Diffuse Axonal Injury
Can occur when brain hemispheres twist around brainstem sharing the white matter (axonal connections)
- Motor vehicle accidents, falls, assaults
- lead to comma, disconnection w structures further down, focal deficits.
What is an example of a focal lesion?
Tumours, abscess, cortical malformations
Where can strokes in the brain occur?
Middle and anterior cerebral artery
or anterior communicating artery - which connects 2 lobes
What can inflammatory problems in the brain be?
Multiple sclerosis - myelination problems
encephalitis - infection
What is a developmental problem in the brain?
ASD
connectivity bw frontal lobe and other areas underpinning problem.
