Lecture 7 Flashcards
What are the major functions of the frontal lobe?
-Top down processes
-Planning, selecting, reasoning, and judgement
-ignoring stimuli/tasks focus and persistence
-Tracking past events and behaviors
-Self-and other-related processes
What functions does the prefrontal cortex specialize in?
-Internal cues
-external cues
-Context cues
-Autonoetic (self) awareness
What are the major subregions of the frontal lobe?
-Lateral PFC
-Medial PFC
-Premotor PFC
-Primary motor cortex
Which subregion specializes in self-identity?
Medial PFC
What does dlPFC stand for and what are its primary functions?
Dorsalateral prefrontal cortex
-working memory, attential selection and planning
-self-regulation
-problem-solving
What does OFC stand for and what are its primary functions?
orbitofrontal cortex
-closely connected to limbic system
-forming social attachments
-regulating emotions
-flexible behaviors & adaptation
What does vlPFC stand for and what are its primary functions?
ventrolateral prefrontal corte
-arousal / alertness
-emotion, reward, motivation, threat detection, and fear
-context-based memory retrieval
-vlPFC lesions cause insomnia
What does vmPFC stand for and what are its primary functions?
ventromedial prefrontal cortex
-self-perception
-self-referential processes
-salience of self-relevant information
-social decision making and emotion regulation
-context-based decision making
-connects to amygdala, temporal lobe, ventral stream, olfactory system, and the thalamus
-lesions make it harder to remember self-relevant information
What does ACC stand for and what are its primary functions?
Anterior cingulate cortex
-emotional expression
-attention allocation (self-relevant direction)
-mood regulation
-self-conscious emotional reactions
-lesions can cause lack of empathy
What does dmPFC stand for and what are its primary functions?
dorsalmedial PFC
-conducts signals between congnitive control and affective brain regions
-generates and regulates emotion
-self-identity processing
-distinguishes self from other
What are the main functions of the medial premotor cortex?
activates self-motivated movement (connects to parietal lobe)
What are the main functions of the lateral premotor cortex?
select movement sequences (plans- and organises behaviour) -> Broca”s region falls largely in this region
What are the main functions of the primary motor cortex?
controls muscle activity (generates the signals for movement)
What part of the Frontal Lobe includes Broca’s area?
Lateral Premotor Cortex
Who was Phineas Gage and why was he important to neuroscience?
● in 1848 he taught us about regional brain functions
● damaged his frontal brain, and after coma he had become a different person
● Suffered social impairment
● White matter recovers much better than grey matter (he lost more white matter -> explains his
fast recovery)
● Can live with frontal lobe damage, but become more primitive (changes your life)
What is dementia?
§ Umbrella term for impaired memory, cognition, and decision-making
* Common causes: Alzheimer’s, Huntington’s disease, multiple sclerosis (MS)
§ Symptoms include poor mood and perception
* May include depression, apathy, and hallucinations
What are the causes and symptoms of frontotemporal dementia?
Dementia mostly impacting the frontal lobe (shrinks), most of the occipital and parietal lobe get spared
Symptoms of Frontotemporal Dementia:
● The most common signs of frontotemporal dementia are usually in the form of extreme changes in behaviour and personality
- Increasingly inappropriate social behaviour
- Loss of empathy and other interpersonal skills (e.g., insensitivity to another’s feelings)
● Affects men and women equally
● 10% - 30% of cases have genetic causes
- Runs in families
- Clumps of abnormal protein forms inside neurons
- Cause of other 70% - 90% of cases is usually unknown
What are symptoms of frontal lobe lesions?
● Motor disturbances
- Fine motor movements, speed & strength
- Movement programming
- Voluntary gaze
- Corollary discharge
- Speech
● Thinking alterations
- Decreases in IQ score
- Loss of divergent thinking (i.e., creativity/problem solving abilities)
- Loss of behavioural spontaneity (more rigide, less flexible)
- Loss of strategy formation
● Difficulty using environmental cues
- Response inhibition
- Risk taking/rule breaking
- Decrease of self-regulation
- Decrease of associative learning
● Poor temporal memory
- Delayed response
- Recency memory
● Impaired social & sexual behaviour
- Pseudodepression/pseudopsychopathy
o ”Pseudo” = not genuine, false (e.g., depression-like traits
but cause is the brain lesion)
● Orbitofrontal syndrome = brain lesion that causes disinhibition (act
more inappropriately)
What are some differences between a brain lesion and a tumor?
What’s the difference between a tumour and a lesion?
- Dementia and lesions have interventions but not treatments
- Brain tumours can be benign (non-cancerous) but still disrupt functioning, BUT Tumours can
often be removed through surgery
How does chronic stress affect PFC neurons?
● PFC neurons generate top-down goals: this occurs through repeated excitatory connections between neurons (dendritic spines)
● Chronic exposure to uncontrollable stress causes loss of spines and loss of dendrites (=loss of synapses)
