Unit 4: Biological Psychology

Biological Systems
Nervous System: The network of nerve cells and fibers that transmits nerve impulses between parts of the body. It starts with an individual nerve cell called a "neuron"
Resting Potential: the electrical potential of a neuron relative to its surroundings when not stimulated or involved in passage of an impulse.
Action Potential: the change in electrical potential associated with the passage of an impulse along the membrane of a muscle cell or a nerve cell
Threshold: You've reached the threshold when enough neurotransmitters reach the dendrites.
All or None Principle: The idea that either the neuron fires or it doesn't.

There is no part way firing.

Neurotransmitters: chemical messengers released by terminal buttons through the synapse.

Acetylcholine (ACH): deals with motor movement and memory.

-lack of ACH has been linked to Alzheimers Disease.

Dopamine: deals with motor movement and alertness.

-lack of dopamine has been linked with Parkinson's Disease.

Serotonin: is involved in mood control

-lack of serotonin has been linked to clinical depression

Endorphins: pain control

-Many and most addictive drugs deal with endorphins.

Drugs can be agonists, or antagonists.

Agonists: they take neuron fire

Antagonists: The stop the neuron from firing

Neurons

Sensory (afferent) Neurons: They take info from the senses to the brain

Inter (relay) neuron: They take messages from the sensory neurons to other parts of the brain or to motor neurons

Motor (efferent) Neurons: They take info from the brain to the rest of the body.

Nervous Systems

Central Nervous System (CNS): the brain and spinal cord

Peripheral Nervous System (PNS): all nerves that are not encase in the bone, and everything except the brain and spinal cord. PNS is divided into two categories...

1. Somatic Nervous System- this nervous system controls voluntary muscle movement and uses motor neurons to transmit signals.
2. Autonomic Nervous System- this nervous system controls automatic functions of the body. This nervous system can be divided into 2 categories... the Sympathetic and Parasympathetic Nervous Systems.

• Sympathetic Nervous System: "Flight or Fight" response. It automatically accelerated heart rate, breathing, dilates pupils, and slows down digestion.
• Parasympathetic Nervous System: automatically slows down the body after a stressful event. Heart rate and breathing slows down, pupils constrict, and digestion speeds up.

Reflexes: normally sensory (afferent) neurons take info up through the spine to the brain.