PSYCH101 - Chapter 2 Lecture notes

Lecture notes

*Chapter 2 includes Neurons, Resting vs. Action Potential, Basic Parts of The Brain Including the Lobes, and the Nervous System.

Basic Parts:

  • Soma: cell body
    • Is what keeps a neuron alive
    • Contains the nucleus
  • Axon: Responsible for sending the information
  • Myelin Sheath: surrounds the axon
    • Speeds up the message being sent
  • Synaptic Knob (AKA Terminal Button): Hold chemicals which are called neurotransmitters (neurotransmitters float across the synaptic gap)
    • Also holds vesicles that have fluid in them (neurotransmitters). They are released and float across the synaptic gap to the dendrites of the next neuron
  • Dendrite: Receive information (opposite of what the axon does)
  • Synaptic Gap (AKA Synapse): The space (gap) between a synaptic knob (the end of the axon) of one neuron to the dendrite of the next neuron

Resting Potential vs. Action Potential

Questions to consider: What are they? What is their function? How does it work?

  • When at rest – nothing is happening (yet)
  • Action Potential – something is happening
    • In other words, with a neuron, that something is the Electrical Neural Impulse/Signal (a signal is being sent)
  • It operates either all or none
    • Either resting (none) or all (something is happening). There's no in between.
    • Ex: Turning a light switch on or off.

Parts of the Human Brain

  • Frontal Lobe: personality, planning, decision making.
    • Left side: Houses the Broca’s area. Where you cannot produce speech. (even if you understand it, you may have a problem producing the language.
  • Parietal Lobe: touch, temperature, position of your body
  • Occipital Lobe: visual information.
    • A way to remember this: the eye doctor (optometrist) also starts with an O
    • This part of the brain deals with visual information
  • Cerebellum: balance and coordination.
  • Spinal Cord (Brain Stem): involuntary functions
  • Temporal Lobe: auditory/auditory information
    • Left side houses the Wernicke’s Area
    • Wernicke’s Area: understanding speech
  • Broca’s Area: Producing speech. (you can understand it but the problem is producing speech)
  • Temporal Lobe/Wernicke’s Area: you can produce speech but understanding it is the problem.

The Nervous System

  • The nervous system is broken down into two main areas:
  • The Central Nervous system (CNS) and Peripheral Nervous system (PNS)
  • The Central Nervous system (CNS): is made up of the Brain and Spinal Cord
  • Peripheral Nervous system (PNS): is a complex system that is broken down into Somatic Nervous System and Autonomic Nervous System.
  • Somatic Nervous System: intentional behaviors, voluntary. The stuff that you know you are controlling.
  • Autonomic Nervous System: Automatic stuff that’s automatically happening; isn’t intentional.
    • Ex: Your heart is automatically beating while you are sitting down.
  • The Autonomic Nervous System is broken down into 2 additional things: the Sympathetic nervous system and Parasympathetic nervous system.
  • Sympathetic Nervous System: your body automatically kicking in and helping you in situations
    • Ex: adrenaline kicking in which helps you
  • Parasympathetic Nervous System: helps you calm down and deal with situations
    • Ex: A parachute slowly lowers you down which helps you calm down.