brain & cellular neurophysiology

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What are the three core functions of the nervous system?

Sensory input integration and motor output.

What is sensory input in the nervous system?

Collecting information from internal and external environments.

What does integration involve?

Processing and interpreting sensory information to decide a response.

What is motor output?

Signals sent to muscles or glands to produce a response.

What is the brain and its key characteristics?

A 1.4kg organ of nerve tissue using 20 to 25 percent of body energy responsible for cognition emotion and memory.

What is the difference between gross and microscopic neuroanatomy?

Gross studies visible brain structures while microscopic focuses on cells and connections.

What are the main divisions of the nervous system?

Central nervous system and peripheral nervous system.

How do the CNS and PNS differ?

CNS processes information while PNS transmits signals to and from the body.

What are the roles of the somatic and autonomic systems?

Somatic controls voluntary movement while autonomic controls involuntary functions.

How do sympathetic and parasympathetic systems differ?

Sympathetic prepares for action while parasympathetic restores calm.

What is the difference between afferent and efferent neurons?

Afferent carry sensory information to the CNS while efferent send motor commands away.

What are the main structural components of a neuron?

Cell body dendrites and axon.

How does information flow through a neuron?

From dendrites to soma to axon.

What role do glial cells play in the nervous system?

They support protect and maintain neurons.

What directional terms are used in brain anatomy?

Anterior means front posterior means back.

What are sulci and gyri and why are they important?

Sulci are grooves and gyri are ridges that increase brain surface area.

What is the interhemispheric fissure?

The deep groove separating the two hemispheres.

What is localisation of function?

Specific brain regions are specialised for particular functions.

What is the function of the precentral gyrus?

Controls voluntary movement as the primary motor cortex.

What is the function of the postcentral gyrus?

Processes touch and sensory input as the primary somatosensory cortex.

What does the sensory homunculus demonstrate?

Body regions are represented based on sensitivity and control.

Why is the homunculus distorted?

Areas needing fine control or sensitivity occupy more cortical space.

What are the main functions of the cerebellum and brainstem?

Cerebellum coordinates movement while brainstem controls vital survival functions.

What is brain lateralisation?

The specialisation of functions between hemispheres.

What functions are dominant in each hemisphere?

Left handles language while right processes faces and prosody.

Why is the left brain vs right brain idea misleading?

Because functions are not strictly separated and overlap significantly.

What is contralateral representation?

Each hemisphere controls the opposite side of the body.

What are cranial nerves responsible for?

They control sensory and motor functions like vision hearing and facial movement.

What is the difference between grey and white matter?

Grey matter contains neuron cell bodies while white matter contains connecting axons.

What is the cerebral cortex?

The outer layer of grey matter responsible for higher cognitive functions.

What are the four lobes of the brain and their roles?

Frontal for decision making parietal for sensory processing temporal for memory and hearing occipital for vision.

What historical shift occurred in understanding cognition?

Early theories placed it in the heart or fluids but later evidence showed it is located in the brain.

What is an action potential?

A rapid electrical signal that travels along a neuron.

What causes an action potential to begin?

The neuron reaching a threshold level of stimulation.

What happens during depolarisation?

Sodium ions enter the neuron making it more positive.

What happens during repolarisation?

Potassium ions leave restoring the negative internal charge.

What is hyperpolarisation?

The membrane becomes more negative than resting potential after repolarisation.

What is the refractory period and why is it important?

A short time where no new action potential can occur ensuring one way signal flow.

What is the role of the sodium potassium pump?

It restores ion balance by moving sodium out and potassium in.

How does an action potential travel along a neuron?

It propagates as a wave of depolarisation along the axon.

What is a synapse?

The junction where one neuron communicates with another.

What is the difference between electrical and chemical synapses?

Electrical use direct ion flow while chemical use neurotransmitters.

How do neurotransmitters transmit signals?

They are released into the synaptic cleft and bind to receptors on the next neuron.

What determines whether a neurotransmitter excites or inhibits?

The type of receptor it binds to on the postsynaptic neuron.

How are neurotransmitters removed from the synapse?

Through reuptake breakdown or diffusion.

How do drugs affect synaptic transmission?

They alter neurotransmitter levels or receptor activity changing communication.

Which videos should be used to revise this topic?

CrashCourse Nervous System Parts 1 2 and 3 alongside lecture slides.