AP PSYCH Unit 1: 1.1-1.3

Interaction of Heredity and Environment, Overview of the Nervous System, and The Neuron and Neural Firing.

Nature

Genetics; the inherent qualities or traits that distinguish us from others, such as eye color and temperament.

Nurture

The influence of external factors on development, including culture, environment, and personal experiences.

Epigenetics

The study of how environmental factors can influence gene expression and transfer behavioral traits.

Heritability

A measure of how much of the variation in traits can be attributed to genetics versus environmental factors.

Identical Twins

Twins that develop from one egg and share the same DNA, often studied for similarities despite different environments.

Fraternal Twins

Twins that develop from two separate eggs, sharing about 50% of their DNA, similar to non-twin siblings.

Peripheral Nervous System

The part of the nervous system that carries information to and from the central nervous system.

Somatic Nervous System

The division of the peripheral nervous system that controls voluntary movements and the relay of sensory information.

Autonomic Nervous System

Part of the peripheral nervous system that controls involuntary bodily functions like heart rate and digestion.

Central Nervous System

Comprises the brain and spinal cord; encased in bone and responsible for processing information.

Neuron

The fundamental building block of the nervous system, responsible for transmitting signals through electrical impulses.

Dendrites

Branches that receive incoming messages from other neurons and transmit them to the soma.

Axon

A long projection that conducts electrical impulses away from the neuron's cell body.

Myelin Sheath

A fatty tissue that surrounds the axon, important for speeding up electrical transmission.

Action Potential

An electrical impulse that travels down the axon and is essential for neuron communication.

Synapse

The gap between two neurons where neurotransmitters are transmitted.

Neurotransmitters

Chemical messengers that facilitate communication between neurons.

Agonists

Substances that enhance neurotransmitter actions and increase their effects.

Antagonists

Substances that inhibit neurotransmitter actions and block their effects.Ex, Botox is an antagonist for ACh.

Depressants

Drugs that slow down CNS functioning, leading to sedation and reduced anxiety. ALCOHOL! is an agonist for GABA, “brake” for CNS.

Stimulants

Drugs that increase CNS activity, enhancing alertness and arousal. CAFFEINE!

Hallucinogens

Substances that alter sensory perception and mood, creating distortions in thoughts and feelings.

Serotonin

A neurotransmitter associated with mood, appetite, and sleep regulation, with low levels linked to depression. You feel “roton” when sad.

Dopamine

A neurotransmitter linked to pleasure and reward, with deficiencies associated with Parkinson's disease. DopaMINE!

Endorphins

Natural painkillers in the body, involved in reducing pain and promoting feelings of well-being. Endorphins end pain.

Acetylcholine

A neurotransmitter important for muscle movement and cognitive functions, including memory.

Tolerance

A condition where increased amounts of a drug are required to achieve the same effect due to repeated use.

Withdrawal Symptoms

Physical and psychological effects felt when a dependent user abstains from a substance.

Sympathetic Nervous System

The division of the autonomic nervous system that prepares the body for 'fight or flight' responses during stress, increasing heart rate and energy availability.

Parasympathetic Nervous System

The division of the autonomic nervous system that promotes 'rest and digest' activities, slowing the heart rate and enhancing digestive processes.

Sensory Neurons

Neurons that carry incoming information from the sensory receptors to the central nervous system; 'afferent' refers to their function of conveying sensory information to the brain.

Motor Neurons

Neurons that carry outgoing information from the central nervous system to the muscles and glands; 'efferent' refers to their role in transmitting signals that dictate motor responses.

DSATs

The path a message takes in a neuron: it begins at the dendrites, which receive incoming messages; then it travels to the soma (cell body), where the nucleus is located; next, the impulse moves down the axon, which conducts the electrical signal away from the soma; finally, it reaches the terminal buttons, where the message is transmitted across the synapse to another neuron.

Excitatory Neurons

Neurons that increase the likelihood of firing an action potential in the receiving neuron, promoting signal transmission.

Inhibitory Neurons

Neurons that decrease the likelihood of firing an action potential in the receiving neuron, inhibiting signal transmission.

Reuptake

The process by which neurotransmitters are reabsorbed by the sending neuron after transmitting a signal, thereby regulating the duration and intensity of the signal.

Action Potential

A sudden and rapid change in electrical charge that occurs when a neuron sends an impulse along its axon, enabling communication with other neurons.

Polarization

The state of a neuron at rest, characterized by a difference in electrical charge across its membrane, with a negative internal charge relative to the outside.

Refractory Period

The brief phase following an action potential during which a neuron is unable to fire another action potential, ensuring the signal travels in one direction.

Epinephrine

A hormone produced by the adrenal glands that significantly contributes to the body's 'fight or flight' response by enhancing heart rate and energy levels.

Direct Agonists

Substances that bind directly to neurotransmitter receptors and activate them, mimicking the action of the natural neurotransmitter. Ex, heroin is a mimic of endorphines.

Indirect Agonists

Reuptake Inhibitors. Substances that enhance the action of neurotransmitters by increasing their release, blocking their reuptake, or preventing their breakdown without binding to the receptors directly. Ex, cocaine inhibits the reuptake of dopamine.

Multiple Sclerosis

Deterioration of the myelin sheath