Psychological Science Flashcards
What percentage of brain volume is frontal lobe?
30%
What are the 3 different ways of subdividing the brain?
Cytoarchitectonic
Thalamic connections
Functional properties, e.g. primary, secondary, association areas.
What is the major form of cytoarchitectonic classification of the brain?
Brodmann’s areas
What does neuropsychology study?
Brain-behaviour relationships
Who was Phineas Gage?
Patient who had:
Penetrating head injury involving at least the left frontal lobe in 1848
Dramatic changes in personality with relative intact intellectual ability
“…his mind was radically changed, so decidedly that his friends and acquaintances said he was no longer Gage.”
What does Luria’s functional systems described the anterior unit as being concerned with?
Planning, executing and verifying behaviour
What is meant by “executive function?”
Umbrella term
Describes inter-related processes responsible for goal directed, purposeful behaviour
Includes emotional and social behaviour as well as cognition
Often considered a ‘frontal lobe’ function
What are the 3 major functional subdivisions of the pre-frontal cortex?
Dorsolateral, medial and orbital pre-frontal cortex
What are the functions of the dorsolateral pre-frontal cortex?
“ Traditional” executive functions:
Working memory
Response selection
Planning and organising
Hypothesis generation
Flexibly maintaining or shifting set
Insight
Moral judgment
Which part of the pre-frontal cortex is concerned with “traditional” executive functions?
Dorsolateral pre-frontal cortex
Which artery supplies the dorsolateral pre-frontal cortex?
Middle cerebral artery
What are the functions of the medial pre-frontal cortex?
Emotional – motivational interface:
At most extreme: akinetic mutism (systems are all intact but lack of motivation to initiate)
Apathy
Initiative
Indifference
Which part of the pre-frontal cortex is concerned with emotional functions?
Medial pre-frontal cortex
Which artery supplies the medial pre-frontal cortex?
Anterior cerebral artery
Where does the site for self-awareness sit in the brain?
In the medial pre-frontal cortex and anterior cingulate cortex
What is the orbitofrontal cortex highly connected to?
Limbic areas
What functions has the orbitofrontal been associated with?
Inhibition - emotional, cognitive and social
Impulsivity
Which artery supplies the orbitofrontal cortex?
Anterior and middle cerebral arteries
Which area of the pre-frontal cortex has “opposite” functions to the medial pre-frontal cortex?
Orbitofronal cortex
What will lesions in the orbitofrontal cortex result in?
Social disinhibition.
Patients taking less time to complete a task but they make the most errors.
Which area of the brain is the last to develop and first to degenerate with age?
Frontal lobe
Which functions are the last to reach maturity?
Executive functions
What is the progression of development of the pre-frontal cortex?
‘Lower order’ functions develop first
‘Higher order’ eg. set shifting and reasoning develop later
Which positive and negative processes take place during frontal lobe maturation?
Positive processes: eg. Neuronal proliferation
Negative processes: eg. “pruning”
Is executive dysfunction a unitary disorder?
No
Where in the brain may executive dysfunction occur?
At any level
What is the role of the pre-frontal cortex in relation to executive functioning?
Coordinator
What are the positive symptoms of executive dysfunction?
Distractability
Social disinhibition
Emotional instability
Perseveration
Impulsivity
Hypergraphia
What are the negative symptoms of executive dysfunction?
Lack of concern
Restricted emotion
Deficient empathy
Failure to complete tasks
Lack of initiation
What do formal neuropsychological tests tend to be most sensitive to?
Dorsolateral pre-frontal cortex lesions
What can mask the difficulties of a dorsolateral pre-frontal cortex lesion?
Structured environment
Which lesions are difficult to formally assess?
Medial and orbitofrontal lesions
What are 3 formal neuropsychological tests?
Tower of London
Stroop test
Rey complex figure test
What are some common causes of executive dysfunction?
Closed Head Injury - Motor vehicle accidents, falls, assaults
Stroke - Middle and anterior cerebral artery, Anterior communicating artery
Psychiatric conditions - Schizophrenia, mania
Dementias - Fronto-temporal dementia, Alzheimer’s disease, Huntington’s disease
Focal lesions - Tumours, abscess, cortical malformations
Inflammatory - Multiple sclerosis o Encephalitis
Developmental - Autism
What is aphasia?
A disturbance in language as a result of brain damage.
What are the 3 different causes of aphasia?
Acute onset
Stroke
Penetrating head injury
Surgical resection
Insidious onset-progressive
Dementia
Neoplastic change
Paroxysmal-episodic
Focal seizures
Migraine
Which hemisphere is home to language?
Left hemosphere
What role does the right hemisphere play in language?
May play a role in non-propositional speech, prosody and paralingistic aspects of speech
What are the 2 branches off the middle cerebral artery?
Superior and inferior divisions.
What does the superior division of the middle cerebral artery supply?
Sensorimotor cortex and ventrolateral prefrontal cortex.