TCE Psychology — background
Nervous System — Flashcards & Quiz
The nervous system is the biological basis of behaviour and experience. Its anatomy is not a listed key content point in the current TASC Psychology Level 3 course. It is useful background for the Consciousness option in the Psychobiological Processes module, which looks at the role of the brain and nervous system in awareness and uses physiological measures (EEG, EMG, EOG, heart rate, body temperature and galvanic skin response) to compare normal waking consciousness with sleep.
Key Points
- Central nervous system (CNS): brain and spinal cord. It integrates information and coordinates responses.
- Peripheral nervous system (PNS): nerves outside the CNS, divided into the somatic (voluntary movement, sensory input) and autonomic (involuntary organ function) divisions.
- The autonomic system has a sympathetic division (arousal, fight-or-flight) and a parasympathetic division (rest and digest, calming).
- Neuron structure: dendrites receive signals, the cell body integrates them, the axon carries the impulse, and axon terminals release neurotransmitters.
- An action potential is all-or-nothing: once threshold is reached the neuron fires fully. Stronger stimuli raise the firing rate, not the size of the impulse.
- EEG records the brain's electrical activity; heart rate, body temperature and galvanic skin response reflect autonomic activity — all used to measure consciousness and sleep.
Common Mistakes to Avoid
- Confusing the CNS (brain and spinal cord) with the PNS (nerves outside them).
- Mixing up sympathetic (arousal) and parasympathetic (calming) divisions.
- Forgetting that action potentials are all-or-nothing — they don't vary in strength, only in frequency.
- Confusing neurotransmitters with hormones — neurotransmitters act across synapses, hormones travel in the blood.
- Treating the EEG as a measure of thoughts — it records overall electrical activity, not their content.
Exam Strategy
Nervous system anatomy is background rather than a listed key content point. Use it to explain the consciousness content: why the EEG shows different brainwave patterns in alertness and in each sleep stage, why heart rate and body temperature fall in NREM sleep as parasympathetic activity increases, and why galvanic skin response rises with sympathetic arousal. Name the measure, say what it records, and link the reading to a state of consciousness.
Sample Flashcards
Q1: Distinguish the central nervous system from the peripheral nervous system.
The central nervous system (CNS) is the brain and spinal cord. It receives information, integrates it and coordinates responses. The peripheral nervous system (PNS) is all the nerves outside the brain and spinal cord. It carries sensory information to the CNS and carries messages from the CNS to muscles, glands and organs, connecting the CNS with the rest of the body.
Q2: What are the somatic and autonomic divisions of the peripheral nervous system?
The somatic nervous system carries sensory information from receptors to the CNS and motor messages from the CNS to skeletal muscles, so it controls voluntary movement. The autonomic nervous system works largely without conscious control, regulating internal organs and glands such as the heart, lungs, digestive system and sweat glands. It keeps the body running whether we are awake or asleep.
Q3: Compare the sympathetic and parasympathetic nervous systems.
Both are divisions of the autonomic nervous system. The sympathetic division prepares the body for action when threatened or aroused: heart rate, breathing and sweating increase and digestion slows. The parasympathetic division calms the body and maintains normal functioning, lowering heart rate and restoring digestion. In NREM sleep, parasympathetic activity dominates, so heart rate and breathing slow.
Q4: Describe the structure of a neuron and how it transmits a message.
Dendrites receive signals from other neurons. The cell body (soma) integrates these signals. If the combined input reaches threshold, an action potential travels along the axon, often sped up by a myelin sheath. At the axon terminals, neurotransmitters are released into the synapse and bind to receptor sites on the next neuron, making it more or less likely to fire.
Q5: What does it mean that an action potential is "all-or-nothing"?
A neuron either fires a full action potential or does not fire at all. If stimulation reaches the threshold, the impulse travels the full length of the axon at the same strength. A stronger stimulus does not make a bigger impulse; instead it increases the firing rate and can activate more neurons. Below threshold, no action potential occurs.
Revision Tip
Pair each nervous-system division with the physiological measure it explains — a short Revizi deck links anatomy to EEG, heart rate and GSR.
Related Concepts
Last updated: 9 October 2026 · 6 sample flashcards