Brain Structure and Function

• The brain has multiple structures and subsystems that communicate to produce seamless experiences.
• Older brain structures are folded inside newer ones.
• The brain's organization starts with the outer shell (cortex) and moves inside to older structures.

Brain Overview

• See https://www.youtube.com/watch?v=0-8PvNOdByc for an overview of brain structures.

Cerebral Cortex

• The Cerebral Cortex, also known as the "neocortex" or "cerebrum", is divided into 2 hemispheres and 4 lobes.

Frontal Lobe

• The frontal lobe is the executive command center for planning, organizing, and prioritizing.
• Keeps emotions in check while also responsible for personality.
• The frontal lobe integrates thought, assesses risk, and controls the motor area for moving body parts.

Parietal Lobe

• The parietal lobe is the center for "Body Sensations".
• It governs kinesthetics, which is knowledge of body parts in motion.
• The parietal lobe integrates somatosensory information like pain, touch, heat, and cold.
• Is very developed in the blind, potentially compensating for the lack of visual input.

Somatosensory Cortex

• The somatosensory cortex processes body sensations, including touch, pain, cold, pressure, texture, roughness, and smoothness.

Motor and Sensory Maps

• The motor and sensory maps refers to structural organization of the the brain between the motor cortex (precentral gyrus) and somatic sensory cortex (postcentral gyrus).

Occipital Lobe

• The occipital lobe functions as the center for vision and contains the primary visual cortex and feature detector cells
• Approximately 40% of the brain handles vision.

Temporal Lobe

• The temporal lobe is responsible for speech, language, hearing (primary auditory cortex), and auditory memory.

Limbic System

• The limbic system is the older part of the brain responsible for emotions, memories, and motivators.
• Key structures include the hypothalamus, pituitary gland, amygdala, and hippocampus.
• The hypothalamus maintains homeostasis by regulating thirst, hunger, temperature, and sexual behavior, and regulates hormones.
• The hippocampus is a key memory area and is often the first to be affected in Alzheimer's disease.
• The amygdala is a powerful emotional area of the brain that deals with fear, anger, and aggression.

Appetite

• Appetite mechanisms within the brain include the lateral hypothalamus, which stimulates hunger.
• The ventromedial hypothalamus contributes to satiety of feeling full.

Brain Stem

• The brain stem, also known as the "old brain", includes medulla and reticular formation structures.
• The medulla controls vital functions such as heartbeat, breathing, and reflexes like swallowing, sneezing, and coughing.
• The reticular formation regulates arousal and alertness.

Cerebellum

• The cerebellum, or "little brain", coordinates movement, procedural memory, and spatial mapping.

Brain and Behavior Relationships

• Phineas Gage was a railroad worker in Vermont (1848) whose frontal lobe and limbic system connection was severed, leading to personality changes.

Brain Hemispheres

• The left brain functions include: right side of body control, number skills, math/scientific skills, written/spoken language, objectivity, analytical thought, logic and reasoning.
• The right brain functions include: left slide of body control, 3-D shapes, music/art awareness, intuition, creativity, imagination, subjectivity, synthesizing, emotion, and face recognition.

Corpus Callosum

• The corpus callosum is a large bundle of over 200 million myelinated nerve fibers that connect the two brain hemispheres, allowing communication between the right and left sides of the brain.

Studying Differing Brain Functions

• Input can be limited to one side of the brain to observe differing responses.
• Observing a natural experiment can be done with looking at people who have had connecting fibers in the corpus callosum severed; communication between hemispheres at higher levels isn't possible in these individuals..

Split Brained Patients

• Split brained patients refers to individuals who have had their corpus callosum severed.
• See https://www.youtube.com/watch?v=ZMLzP1VCANo for more information.

Explore the intricate structures and functions of the brain, including the cerebral cortex, frontal lobe, and parietal lobe. Learn how these components work together to create our experiences and control body movement. Understand the roles of planning, sensory processing, and emotional regulation within the brain.