Class 14 - Frontal Lobe Flashcards
What are the divisions of the prefrontal cortex?
Dorsolateral prefrontal, orbito frontal and medial frontal cortices
Where does the prefrontal cortex receive its input?
Dorsomedial nucleus of the thalamus
Where does the motor cortex project to?
Spinal motor neurons, cranial nerves, basal ganglia and red nucleus
Where does the premotor cortex project to?
spine, motor cortex
Where does the premotor cortex receive projections from?
PE and PF parietal areas, dorsolateral prefrontal area
Where does the eye fields receive projections form?
PG and superior colliculus
Where is the dorsolateral prefrontal area connected to?
Posterior parietal, STS, cingulate cortex, basal ganglia, superior colliculus, tegmentum
Where is the orbital frontal cortex connected to?
Receives from temporal lobe, amygdala, gustatory cortex, somatosensory cortex, olfactory cortex, dopaminergic cells in tegmentum
Projects to hypothalamus and amygdala
Is the prefrontal cortex a major convergence zone?
Yes. Emotion, auditory, somatosensory, visual, memory/learning and motor
What are the two main functions of the frontal lobe?
Goal-directed behaviour and executive functions (planning, adaptation, ignoring distractions, contextual cues)
What are the main functions of the premotor cortex?
Selecting movements to be executed or choosing behaviour in response to external cues
What are types of multiple cues the prefrontal cortex can respond to?
Internal (working memory, dorsolateral frontal) External (feedback about rewarding stimuli, orbital frontal cortex) Context (regulation of external reactions, orbital and ventromedial frontal) Autonoetic awareness (self-knowledge, ventromedial frontal cortex)
What are the three categories towards doing a complex executive task?
Shifting, updating (working memory), inhibition
What is the difference between hot and cold executive functions?
Cold = only cognition (IQ) Hot = emotion and social interaction (EQ)
What are the five frontal cortical circuits?
Motor (Motor, oculomotor)
Cognitive (dorsolateral, orbitofrontal, anterior cingulate circuits)
What does the rostral prefrontal cortex do?
Metacognition (integration of everything in the frontal lobe)
What does the superior medial circuit do?
Energization
What is the left frontal lobe better at?
Language and encoding memories
What is the right frontal lobe better at?
Non verbal movements, facial expresion and retrieving memories
What has less asymmetry, the posterior or anterior frontal lobe?
Posterior
Why are bilateral lesions usually required to constrain frontal function?
There is less asymmetry in the frontal lobe. In other words, frontal love function is hetergeneous
What can visual search tasks figure out?
The systematic order that they search for things in a picture of random shapes. Can also test visuospatial function and attention
What does the Wisconsin Card Sorting Test do? How does it work?
Tests for response inhibition if they cannot shift to a different concept, or sort randomly.
They have to sort cards, and then figure out the sorting criteria. Then you change the sorting criteria. They then need to shift to a different concept.
Does the Wisconsin Card Sorting Test only diagnose frontal lesions?
No, there are other lesions that could impair this task - e.g. ventral recognition stream
What is the Stroop test?
Read out the color of the word when the word says a different color. Diagnoses response inhibition
What does the tower of London test for?
Mainly planning but also some working memory
What does the Iowa Gambling task do?
Assess for “hot” executive functions. There are small rewards and small penalties. There are large rewards and large penalties. The best thing to do is choose small rewards. However, impaired people tend to pick the high risk high reward cards.
What can frontal lobe patients do with tinker toys
Make shitty underdeveloped creations
What is prefrontal lobotomy?
Ablation of the prefrontal cortex. Initially for psychosis
