Chapter 2: The Biology of Behavior and Consciousness

Neuroplasticity

• The brain’s ability to change and adapt by reorganizing itself after damage or through learning.

Parts of a Neuron

• Dendrites: Receive messages from other neurons.

• Axon: Sends messages away from the neuron.

• Synaptic Gap: The space between neurons where neurotransmitters are released.

Neural Communication

• Neurons communicate via electrical impulses and neurotransmitters that cross synaptic gaps.

Action Potential

• A brief electrical charge that travels down an axon to transmit a signal.

Reuptake

• The process where neurotransmitters are reabsorbed by the neuron after transmitting a message.

• Reuptake occurs in the context of synaptic transmission, which is part of how neurons communicate with one another.

Neurotransmitters and Their Effects

• Dopamine: Influences movement, learning, and emotion (linked to Parkinson’s and schizophrenia).

• Serotonin: Affects mood, hunger, and sleep (linked to depression).

• Endorphins: Natural painkillers and mood enhancers.

Divisions of the Nervous System

• Central Nervous System (CNS): Brain and spinal cord.

• Peripheral Nervous System (PNS): Connects CNS to the body.

  • Somatic Nervous System (SNS): Controls voluntary movements.

  • Autonomic Nervous System (ANS): Controls involuntary functions.

    • Sympathetic Nervous System: Activates "fight or flight."

    • Parasympathetic Nervous System: Calms the body after stress.

Endocrine System

• Uses hormones to regulate body functions.

• Pituitary gland: "Master gland" that controls growth and other endocrine glands.

• Adrenal glands: Release adrenaline during stress.

Brain Structures and Their Functions

• Amygdala: Involved in emotion regulation, especially fear and aggression.

• Hippocampus: Critical for forming new memories and learning.

• Thalamus: Sensory relay center EXCEPT SMELL

• Cerebellum: Coordinates movement and balance.

• Medulla: Controls heartbeat and breathing.

• Pons: Coordinates movement and sleep.

Effects of Sleep Deprivation

• Decreases focus, weakens the immune system, and increases stress.

Dream Theories

Freud’s Wish-Fulfillment Theory

• Dreams represent unconscious desires, thoughts, and conflicts.

• Manifest content (what we remember) vs. latent content (hidden meaning).

Information Processing Theory

• Dreams help process and store memories.

Physiological Function Theory

• Dreams serve a biological function by preserving neural pathways.

Activation-Synthesis Theory

• The brain tries to make sense of random neural activity.

Cognitive Development Theory

• Dreams reflect cognitive growth and development over time.