Chapter 3: Brain, Mind, and Behaviour – Psychology Study Notes

Chapter 3: Brain, Mind, and Behaviour

Overview

This chapter explores the biological foundations of psychological processes, focusing on the structure and function of the brain, nervous system, endocrine system, neural communication, and the genetic and environmental factors that shape behaviour.

The Human Brain from the Top Down

Unit 3.1: The Biology of You

Neuroscience is the study of how nerves and cells send and receive information from the brain, body, and spinal cord. It uses biological, chemical, and electrical processes to complete everyday tasks and functions.

• Structure-function relationships: Neuroscientists often cite how specific brain structures support particular functions.

• Top-down approach: Complex functions are broken down into basic actions.

• Nature and nurture: Both genetic (nature) and environmental (nurture) factors influence brain function.

• Neurodiversity: Appreciation for differences in how brains function across individuals.

Unit 3.2: The Nervous System

The nervous system is a network of neurons that runs throughout the brain and body, enabling communication and coordination of functions.

• Neurons: Cellular building blocks of the brain; three main types:

  • Motor neurons: Send messages to the world, enabling movement.

  • Sensory neurons: Carry information from the body and environment to the brain.

  • Interneurons: Connect other neurons, interpret, store, and retrieve information.

• Spinal cord: Bundle of nerves connecting the body to the brain, housed in the spine.

• Central Nervous System (CNS): Composed of the brain and spinal cord; exchanges information between brain and body.

• Peripheral Nervous System (PNS): Sensory and motor nerves throughout the body; divided into:

  • Somatic Nervous System (SNS): Voluntary commands and external sensations.

  • Autonomic Nervous System (ANS): Involuntary commands and internal sensations.

• Autonomic Nervous System branches:

  • Sympathetic Nervous System: Mobilizes energy (fight-or-flight).

  • Parasympathetic Nervous System: Restores energy (rest-and-digest).

Nervous System	Central Nervous System	Peripheral Nervous System
	Brain, Spinal Cord	Somatic (voluntary), Autonomic (involuntary)
		Sympathetic (fight-or-flight), Parasympathetic (rest-and-digest)

Unit 3.3: The Endocrine System

The endocrine system is a network of glands that release hormones into the bloodstream, regulating bodily activities.

• Hormones: Chemical messengers that influence body and brain functions.

• Adrenal glands: Located above the kidneys; produce hormones for the fight-or-flight response (adrenaline, cortisol).

• Hypothalamus: Governs survival-related behaviours and links nervous and endocrine systems.

• Pituitary gland: Master gland; regulates other glands and releases oxytocin.

• Other glands: Pineal (sleep), testes (testosterone), ovaries (estrogen), pancreas (blood sugar).

Gland	Main Function
Hypothalamus	Links nervous and endocrine systems
Pituitary	Regulates other glands
Adrenal	Fight-or-flight response
Pancreas	Regulates blood sugar
Ovary/Testis	Sex hormones

Additional info:

These notes are based on textbook-style slides and images, with some inferred details for completeness and clarity.