What are the two main types of cells in the nervous system?
Neurons (signal transmission) and Glial cells (support and protection).
How many neurons are in the human brain, and how many connections do they form?
~100–150 billion neurons forming ~10¹⁵ connections.
What are the main components of a typical neuron?
Dendrites (receive signals), Cell Body/Soma (integrates signals), Axon (sends signals).
What is the function of the axon hillock?
It is the site where the action potential is initiated.
What is the role of myelin?
Insulates axons to speed up action potential transmission.
Which glial cells produce myelin in the CNS and PNS?
: CNS: Oligodendrocytes | PNS: Schwann cells
Name two other types of glial cells and their functions.
Astrocytes (support, regulate nutrients & blood flow) and Microglia (clean up debris, immune defense).
What are the three functional types of neurons?
Sensory neurons (afferent), Motor neurons (efferent), Interneurons (connect CNS neurons).
What is the difference between CNS and PNS?
CNS: brain and spinal cord; processes info. PNS: all other neural pathways; connects CNS to body.
Describe the basic pathway of a reflex arc.
Stimulus → Sensory neuron → Interneuron → Motor neuron → Muscle response
What is an action potential?
A rapid change in electrical charge across a neuron’s membrane that propagates a signal.
What ions are most important for generating an action potential?
Sodium (Na⁺) and Potassium (K⁺).
What is the resting potential of a neuron?
About -70 mV; inside negative relative to outside.
Outline the steps of an action potential.
1) Resting state, 2) Depolarization (Na⁺ enters), 3) Repolarization (K⁺ exits), 4) Hyperpolarization, 5) Return to rest.
What is the all-or-none principle?
A neuron fires an action potential at full strength or not at all, never partially.
How do neurons communicate across synapses?
Action potential → calcium influx → neurotransmitter release → binds postsynaptic receptors → postsynaptic depolarization or hyperpolarization.
What is the difference between excitatory and inhibitory synapses?
Excitatory → depolarizes postsynaptic neuron, increasing likelihood of firing. Inhibitory → hyperpolarizes postsynaptic neuron, decreasing likelihood of firing.
What is spatial summation?
Multiple presynaptic inputs at nearby locations combine to increase effect.
What is temporal summation?
Multiple presynaptic inputs arriving close in time combine to increase effect.
How does the nervous system produce behavior?
Through networks of neurons that process information via excitatory and inhibitory signals.
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Neuroscience20
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Brain Structures63
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Brain Measurement Techniques22
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Memory14
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Review session notes28
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Cognitive Development21
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Attachment29
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Identity and Social Psychology8
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Nature Vs Nurture8
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Personality traits22
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Social influence21
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Personality Disorders12
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Anxiety and Depression Disorders31
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Therapy22
