Parts of the Brain => Hands

1. Introduction

A. Purpose

  • i. Learn the major parts of the brain

  • ii. Use your hands as a model

2. Hands as a Model for the Brain

A. Skin on Hands

  • i. Darker side represents the cortex (gray matter)

  • ii. Lined with neuron cell bodies (soma)

  • iii. Keeps the neuron healthy and functioning

B. Muscles in Hands

  • i. Represent white matter

  • ii. Composed of neuron axons

  • iii. Axons carry information between neurons

3. Fist Shape

A. Importance

  • i. Represents the compactness of gray matter in the skull

4. Hands and Wrists

A. Crossing Wrists

  • i. Touching backs of hands

  • ii. Left hemisphere controls right side of body

  • iii. Right hemisphere controls left side of body

B. Corpus Callosum

  • i. Area where hands touch

  • ii. Bundle of nerves connecting the two hemispheres

  • iii. Facilitates communication between hemispheres

  • iv. Analogy: Golden Gate Bridge of the brain

C. Wrists

  • i. Represent the brainstem

  • ii. Located at the bottom of the brain

  • iii. Regulates essential life functions (breathing, heart rate, etc.)

  • iv. Signal crossover: right side to left brain and vice versa

D. Arms

  • i. Represent the spinal cord

  • ii. Extends down the back

  • iii. Sends and receives information from the body

5. Left Hemisphere

A. Frontal Lobe

  • i. Represented by front fingers

  • ii. Responsible for complex and abstract abilities

  • iii. Located behind the forehead

  • iv. Functions: planning, imagining futures, emotional control

  • v. Development continues into mid-20s (impulsivity in kids/teens)

B. Parietal Lobe

  • i. Represented by extended index and middle fingers

  • ii. Integrates sensory information

  • iii. Responsible for sense of space, navigation, and touch

  • iv. Unequal prioritization (homunculus map shows emphasis on hands and face)

6. Occipital Lobe

A. Location

  • i. Back of the brain

  • ii. Responsible for visual information

B. Sensation

  • i. Hitting the back of the head may lead to seeing stars

  • ii. Brain protected by cerebrospinal fluid (cushions against injuries)

7. Temporal Lobe

A. Appearance

  • i. Thumb represents temporal lobe

  • ii. Back is connected to parietal and occipital lobes

  • iii. Front section can be lifted away

B. Functions

  • i. Responsible for understanding sounds and speech

  • ii. Analogy: Thumb for talking

8. Limbic System

A. Location

  • i. Inside the temporal lobe

B. Functions

  • i. Responsible for emotions, learning, and memory

  • ii. Contains the amygdala and hippocampus

C. Amygdala

  • i. Almond-shaped structure below the thumbnail

  • ii. Responsible for basic emotions

D. Hippocampus

  • i. Located near the bone of the thumb

  • ii. Responsible for learning and memory