Lecture Notes: Frontal Lobes Anatomy and Function

Introduction

• Speaker: Dr. Catherine Price
• Moderator: Annie Reyes, Dr. Casey Hewitt
• Series: 7-week neuroanatomy lecture series by experts
• Objectives: Provide free, high-quality didactic opportunities
• Disclaimer: Not a substitute for formal education; views of speakers are their own
• Q&A: Led by Dr. Casey Hewitt; questions via Q&A box, recording available later

About Dr. Catherine Price

• Position: Associate Professor at University of Florida, Gainesville
• Licensing: Board-certified in Clinical Neuropsychology
• Research: Focuses on white vs. subcortical gray matter and cognitive profiles, predictive value of cognitive integrity on diseases, and cognitive changes post-surgery

Lecture Focus: Frontal Lobes Anatomy and Function

Key Topics

1. Anatomy of Frontal Lobes
2. Basic Roles of Frontal Lobes
3. Clinical Evaluation and Case Studies

Anatomical Boundaries

• Regions to Know: Motor strip, pre-motor area, prefrontal cortex
• Lateral and Medial Sides of the Brain: Cortex areas, motor functions
• Medial Side: Motor area, pre-motor, anterior cingulate, orbitofrontal region

Pre-motor Cortex

• Functions: Responding to stimuli, eye movement, preparing motor cortex signals
• Divisions: Dorsal and ventral parts

Prefrontal Cortex

• Complications: Multiple regions, cyto-architecturally distinct
• Areas: Orbital frontal region, medial prefrontal cortex, dorsolateral prefrontal cortex
• Functional Importance: Planning, working memory, cognitive control

Basal Ganglia Connections

• Components: Caudate nucleus, putamen, globus pallidus, subthalamic nucleus, substantia nigra
• Connections: Frontal lobe connected to these structures via white matter circuits
• Neurotransmitters: Dopamine, acetylcholine, serotonergic pathways

Neuroanatomical Loops

• Three Neurobehavioral Circuits: Cortical-striatal-pallidal-thalamic loops
• Impact: Lesions in any part of the loop can produce similar behaviors

Functional Roles of the Frontal Lobes

• Mediator: Between environment and body
• Functions: Creation, rule-making, decision-making
• Higher Order Thinking: Combines biological drives with external behaviors
• Regulation: Balances internal stimuli with external actions

Executive Function as a Concept

• Key Point: Executive function is a function, not a region
• Involvement: Wider network beyond just the frontal lobes

Specific Regions and Their Functions

Orbital Frontal Cortex

• Functions: Personality, social behavior, emotional responses
• Damage Effects: Impulsivity, poor social skills, disinhibition
• Assessment: Observation, Iowa Gambling Task

Medial Frontal Cortex

• Functions: Initiation of actions, emotional expression
• Damage Effects: Apathy, reduced motivation, akinesia
• Assessment: Apathy scales, caregiver reports

Dorsolateral Prefrontal Cortex

• Functions: Working memory, planning, inhibition
• Damage Effects: Perseveration, disorganization, hyperkinetic behavior
• Assessment: Stroop test, clock drawing test

Clinical Presentations

Case 1: Mr. A

• Age: 64
• Symptoms: Increased pornography use, spending, affairs, disorganized
• Diagnosis: Frontotemporal dementia, behavioral variant

Case 2: Mr. M

• Age: 58
• Symptoms: Lethargy, slow movement, depression
• Diagnosis: Intractable depression

Conclusion

• Frontal Lobes: Largest and complex; mediator for behavior
• Recommendation: Keep reading and learning about the frontal lobes
• Acknowledgements: Thanks to everyone for attending and participating in the lecture series

Q&A Highlights

• Awareness of Dysfunction: Many patients may not realize something is wrong
• Explaining to Patients: Use simple analogies (e.g., apple for brain structure), be concrete and kind
• Resources for Learning: Kolb & Whishaw, Lezak's Neuropsychological Assessment
• Frontal Lobe Functions: Complex, involve connections to cerebellum and other brain regions

Next Lecture

• Speaker: Mary Pat McAndrews from University of Toronto
• Topic: Learning and Memory
• Date: Next Monday, August 23rd