Wk12 Frontal Lobes & Higher Functions Flashcards
What are some “supervisory functions” of the Fontal lobes? 3
WM, inhibition, control, interacting with social/physical environment
What was the main thing that happened to Phineas Gage after his accident?
He underwent a dramatic personality shift
What area of brain was damaged, phineas gage?
frontal cortex
What neuropathology was associated with Arnold Pick? 2
Frontotemporal atrophy “knife like” thinning of the gyri in the frontal and temporal lobes Swollen “pick” cells with abnormal tau proteins
What were abnormal spontaneous behaviours associated with frontotemporal dementia in Arnold Pick’s case?
Inappropriate jocularity Echolalia (repeating others’ words) Echopraxia (repeating gestures) Disinhibited approach or utilisation behaviours Unkempt, depsressed Primitive reflexes (grasp, suck, snout, toes)
What are the classic frontal lobe syndromes? (Which may not actually exist) 2
Orbitofrontal dysfunction: Aggression & social inappropriateness, apathy, disinhibition Dorsomedial or dorsolateral dysfunction: apathy, decrease are spontaneity.
What was more severe in Pick’s case of FTD, speech and language or memory impairment?
Speech and language not as severe as behavioural
What movement disorders were found in Pick? 2
Perseveration & akinesia (rigidity)
What were two early forms of frontal lobotomy?
Leucotome (extruding cutting wire from a rod) Transorbital sectioning (through the eye)
What was the aim of frontal lobotomies at the time?
Calm down severe psychiatric patients
Who invented transorbital lobotomies?
Walter Freeman, the travelling man
What did Fulton and Jakobsen think of Freemans transorbital lobotomy?
They didn’t like it and said it would be better to use a gun if they wanted ‘efficiency’
Why were frontal lobotomy patients “stimulus-bound”? 3
They reacted to whatever was in front of them and didn’t respond to imaginary situations, rules, or plans in the future.
What neuropathology was found in W.R.? How did his life change?
Astrocytoma, very large. Invading lateral prefrontal cortex. Lost interest/motivation in many things & couldn’t attach emotions to his own prognosis.
What does damage to the frontal lobes seem to cause?
Apathy Irritibility, aggression Poor social control, inappropriateness Poor planning, self-direction Distractibility Poor motor control Stimulus bound
What are on-line manipulations?
Interpreting the environment based on previous knowledge
Do mental operations in the WM involve rehearsal?
No
Where does on-line manipulation occur in the brain?
In working memory, lateral prefrontal cortex.
What happens when you change the instruction but not the stimulus in a neuropsychological test?
Change the cognitive function being used.
What is involved in working memory manipulations?
Internal representation used to reorganise information
How do McCarthy et al 1994 test spatial working memory?
respond to a display where a stimulus occurs in a previously presented location. Vs. just respond to the colour red (control)
What is the Wisconsin card sorting test?
Ps sort cards based on categories of colour, shape or number of objects on the cards. Experimenters only provide yes or no feedback on the category.
What does the Wisconsin card sorting test test for?
Concept formation concept shifting concept perseveration
What does normal performance on the wisonconsin card sorting test show?
People given correction on their errors then shift the category they use.
What happens when non-typical people do the WCS test?
No category shift based on error (perseveration)
What happens in the WCS test, (what does it demand of the brain)?
Information must be integrated with info that was relevant in previous trial - manipulate information on line
What is the function of the prefrontal cortex in the WCS test?
Inhibit dimension that is not relevant Dynamically sift and filter possible alternatives
How can you typically test chronogenesis?
Recency task: “which event happened more recently?”
Is it recognition or recency which is impaired in frontal lobe impairment?
Recency; they can still recognised what happened.
What are the impacts of memory organisation impairments on behaviour?
Can’t arrange sub actions into a correct sequence; or generate a plan for action
How has goal-oriented behaviour been tested in the real world?
Running shopping errands with a list.
What are three processes involved in goal-oriented behaviour? 3
- Identify goal and select sub-goals 2. Anticipate consequences 3. Determine what is required to achieve sub-goals
What is involved in selecting appropriate sub goals? 2
Filter irrelevant info Select best way to achieve goal (evaluating consequences and alternatives)
What is the role of the ACC?
Considering and evaluating appropriate goals and sub goals on the basis of affective feedback. (As well as modulation of autonomic responses)
What are the inputs 3 and output of the ACC?
In: - limbic structures (thalamus, striatum) - brainstem Out: Prefrontal cortical areas
What are 3 important connections concerning the ACC?
- Projects to motor cortex for control 2. Reciprocal connections with lPFC for cognition/conflict monitoring 3. Afferent from thalamus & brainstem for drive/arousal functions
What happens when people attend passively to a single visual feature out many possible ones (colour, shape, motion)? How does this change when asked to monitor changes in all three dimensions?
Passive = enhanced feature specific activity Divided attention = ACC activation
What are specific functions of the ACC? 2
Divided attention (keeping track of multiple info sources) Amplifies emotional signals
What is the OFC involved in?
Social and emotional judgement & decision-making
Which area deals with choosing how to act? How?
OFC - integrates new info with goals, values, current situation
What happened to Elliot (Damasio 1994 - OFC)?
Risky business ventures and bankruptcy - could speak about his failings but was unconcerned.
What does skin conductance show about OFC damage and decision making? How?
Less anticipation of rewards and punishments. Skin conductivity measured against controls during card playing.
What are the clinical implications of OFC reducing reward and punishment salience?
Can’t use these to motivate behaviours. Instead must relying on learning through repetition.
What was impaired in J.S. (Acquired sociopathy)? 5
Poor recognition of visually presented emotions Reduce autonomic response to visual emotions Poor identification of social behaviour violations Poor theory of mind Poor judgement of moral vs social transgressions
What may explain acquired sociopathy in J.S.?
Impaired ability to generate expectations of negative reactions in others, and suppressing inappropriate behaviour (OFC)
