Class 4 - Neurotransmitters and Mind-Body Connections

Question 1

Important Brain Structures

Answer 1

Pre frontal cortex
- Insight, personalities, judgement, problem solving, social responses

Limbic System

• Basal nuclei (basal ganglia): movement
• Thalamus and hypothalamus: sensory gateway
• Hippocampus: memory
• Amygdala: emotion

Pineal gland

• Helps with sleep and wake cycles (melatonin)
• Melatonin also affects immune systems

Brain Stem
ANS

Question 2

Cholinergic Messengers

Answer 2

• Acetylcholine
• People with Alzheimer’s and Down Syndrome have less cholinergic fibres and lower levels of Ach
• Ties into learning and memories

Question 3

Biogenic Amine Messengers

Answer 3

• Dopamine
• Norepinephrine/epinephrine
• Serotonin

Question 4

Amino Acid Messengers

Answer 4

• Glutamate - excitatory

- Gamma Aminobutyric Acid (GABA) - inhibitory and calming

Question 5

Neuropeptide Messengers

Answer 5

• Endorphins and encephalin - pain suppressants, runner’s high
• Somatostatin and Substance P - increases pain
• Melatonin

Question 6

Schizophrenia

Answer 6

• Shattered mind
• Prevalence is 1% worldwide, more males than females affected
• Symptoms start between 16-30 years of age
• Etiology unknown: not purely genetic, stress events and viral infection in utero can trigger
• Chemical brain imbalances: increased glutamate, changes in dopamine, GABA and serotonin
• Structural changes: atrophy of the hippocampus (bc of the high levels of glutamate) and enlarged ventricles in the brain
• Biological cause - not just in the head

Manifestations:
Positive:
- Hallucinations
- Delusions
- Thought disorders
- Movement disorder
- Special language
Negative:
- Inability to express emotion
- Hygiene 
- No enjoyment
Cognitive:
- Attention
- Memory
- Planning
- Makes it hard to sustain a job

Question 7

Major Depressive Disorder

Answer 7

Etiology:

• Genetic disposition plus a trigger
• Stress hormonal changes (post-partum)
• More prevalent in males
• 10-15% of population

Brain Structures:

• Hippocampus is smaller
• Amygdala is larger
• Hypothalamus - pituitary - thyroid
• Hypothalamus - pituitary - adrenal gland

Messengers:

• Decreased norepinephrine, serotonin, dopamine (excitatory)
• ? melatonin, GABA, cortisol, acetylcholine

More than feeling sad:

• Emotional, cognitive, physical, behavioural componenets
• Decreased pleasure, mood and energy
• Increased sleep, decreased libido
• Feelings of worthlessness and guilt
• Trouble making decisions, concentrating
• Headache, stomach pain, joint pain, other pain
• It can manifest as rage

Question 8

Bipolar Affective Disorder

Answer 8

• Cyclical episodes of mania and depression
• Van Gogh

Mania

• Elevated moods
• Hyper, energetic, elated, euphoric, creative
• Depression

Messengers

• Glutamate
• GABA
• Serotonin
• Dopamine
• Norephinephrine
• Melatonin

Question 9

Parkinson’s Disease

Answer 9

• Dysfunction of the substantia nigra in the basal ganglia

- Decreased secretion of dopamine