Psych Exam 2

Acetylcholine(ACh)

Location: Basal forebrain, brain stem, and in the neuromuscular junction in peripheral

Function: cognition, muscle movement

• Myasthenia Gravis

• Low levels of ACh in Alzheimer disease

Glutamate

• Most common neurotransmitter

• Only excitatory - can be excitotoxic

• in MSG(makes food more flavorful)

GABA

• only inhibitory

• Is used as a general anesthetic, antianxiety drug, and antiepileptic drug

Dopamine

Many functions: pleasure, addiction, negative and positive reinforcement, motor functions, hormone control

• associated with Parkinson disease in low levels

• associated with Schizophrenia in high levels

Serotonin

Many functions: emotions, appetites, social relationships, aggression, sleep, sex

• LSD mimics it

Norepinephrine

• Survival related attention

• high levels lead to anxiety

Opiates

Functions: addictive painkillers, pleasure, GI functions, sleep

Who first discovered neurotransmission and how did they discover it?

Otto Loewi: Took two frog hearts one with the vagus nerve stump still attatched one without → applied an electrical signal to the heart with the vagus nerve stump, slowing down heart contractions → transfered the saline from the electrically stimulated heart to the one without the vagus nerve stump → the seconds hearts contractions also slowed down

What neurotransmitter did Otto Loewi discover?

Acetylcholine

Divergence

One neuron signals many cells

Convergence

Many neurons signal fewer cells

Myasthenia Gravis

• Immune system attacks ACh receptors → disrupts signal transmission → muscle weakness & fatigue

• treatment: control ACh esterase

How is Alzheimers disease slowed?

Through treatment with AChEI

Neural Organization

Neuron → Nuclei → Circuit/pathway → Network

Central Nervous System

Consists of brain & spinal cord

Peripheral Nervous System

Location: Consists of nerves branching out from CNS

Contains: Somatic & Automatic Nervous Systems

Somatic Nervous System

Location: PNS

Function: communicates with sense organs and voluntary muscles

Contains: Afferent & Efferent Neurons

Automatic Nervous System

Location: PNS

Function: Communicates with internal organs and glands to make involuntary actions

Contains: Sympathetic, Parasympathetic, and Enteric Nervous Systems

Sympathetic Nervous System

Location: Automatic Nervous System (PNS)

Function: Manages flight or fight response by simulating adrenaline glands and controlling heartbeat, blood pressure, respiration, and temperature

Parasympathetic Nervous System

Location: Automatic Nervous System (PNS)

Function: Preserves homeostasis by controlling the body’s ability to rest, digest, and repair

Enteric Nervous System

Location: Automatic Nervous System (PNS)

Function: Controls GI track

Spinal Cord

Location: CNS

Function: Facilitates communication between the brain and the body

Contains: Gray matter, White matter, Spinal nerves

What are four ways the brain is protected?

• Skull

• Meninges - 3 layers of protective tissue that anchor the liquid brain

• Cerebrospinal Fluid - located in the four ventricles of the brain, cushions the brain, brings nutrients, and removes waste

• Blood-brain barrier - glial sheath over blood vessels in the brain