Neurophysiology Overview Quiz

Neurophysiology examines the function of the nervous system.
It focuses on the electrical and chemical processes that underlie neural activity.

Basic functional units of the nervous system.
Types of neurons:
- Sensory neurons: Transmit sensory information to the central nervous system (CNS).
- Motor neurons: Convey signals from the CNS to muscles and glands.
- Interneurons: Connect neurons within the CNS.

A rapid change in membrane potential that constitutes a signal.
Phases:
1. Resting potential: Neuron is at -70 mV, primarily due to potassium ions (K+).
2. Depolarization: Sodium ions (Na+) influx raises the membrane potential.
3. Repolarization: K+ efflux restores the resting potential.
4. Hyperpolarization: Temporary increase in negativity due to excess K+ outflow.

Chemical messengers that transmit signals across synapses.
Key neurotransmitters:
- Glutamate: Major excitatory neurotransmitter.
- GABA (Gamma-Aminobutyric Acid): Major inhibitory neurotransmitter.
- Dopamine: Involved in reward and motor control.
- Serotonin: Regulates mood and sleep.

Comprises the brain and spinal cord.
Responsible for processing and integrating information.
Key structures:
- Cerebrum: Involved in higher cognitive functions.
- Cerebellum: Coordinates movement and balance.
- Brainstem: Controls vital functions like heartbeat and breathing.

Connects the CNS to the rest of the body.
Divided into:
- Somatic nervous system: Controls voluntary movements.
- Autonomic nervous system: Regulates involuntary functions; further divided into sympathetic and parasympathetic systems.

Methods used to study electrical properties of neurons:
- Patch-clamp technique: Measures ionic currents through individual channels.
- Extracellular recording: Monitors the electrical activity of multiple neurons.

Common conditions include:
- Epilepsy: Characterized by abnormal electrical activity in the brain.
- Parkinson’s disease: Degeneration of dopamine-producing neurons.
- Multiple sclerosis: Demyelination of neurons affecting conduction.

Neurophysiology is vital for understanding how the nervous system operates.
Insights gained inform treatments for neurological disorders and enhance our understanding of behavior and cognition.

Serve as the basic functional units within the nervous system.
Types of neurons include:
- Sensory neurons: Relay sensory information to the central nervous system (CNS).
- Motor neurons: Transmit signals from the CNS to muscles and glands, facilitating movement.
- Interneurons: Connect and process information between other neurons within the CNS.

Represents a rapid alteration in membrane potential that acts as a neural signal.
Phases of action potential include:
- Resting potential: The neuron maintains a charge of -70 mV, primarily influenced by potassium ions (K+).
- Depolarization: Sodium ions (Na+) influx causes a rise in membrane potential, shifting it toward a positive value.
- Repolarization: Potassium ions (K+) exit the neuron, restoring the resting potential.
- Hyperpolarization: An excessive outflow of K+ results in a temporary increase in negativity of the membrane.

The mechanism by which neurons communicate across synapses.
Key steps in synaptic transmission:
- Action potential arriving at the axon terminal prompts opening of voltage-gated Ca²+ channels.
- Calcium ions (Ca²+) enter the terminal, leading to the release of neurotransmitters into the synaptic cleft.
- Neurotransmitters bind to receptors on the postsynaptic neuron, generating either excitatory (EPSPs) or inhibitory (IPSPs) postsynaptic potentials.

Function as chemical messengers facilitating signal transmission across synapses.
Important neurotransmitters include:
- Glutamate: The primary excitatory neurotransmitter, crucial for initiating action potentials.
- GABA (Gamma-Aminobutyric Acid): The main inhibitory neurotransmitter, involved in reducing neuronal excitability.
- Dopamine: Plays a significant role in reward pathways and motor control.
- Serotonin: Influential in regulating mood, emotions, and sleep patterns.

Comprised of the brain and spinal cord, acting as the main processing center for information.
Key structures within the CNS include:
- Cerebrum: Associated with higher cognitive functions including reasoning and decision-making.
- Cerebellum: Essential for coordinating movement, precision, and balance.
- Brainstem: Governs vital functions such as heart rate, breathing, and sleeping.

Serves as a connection between the CNS and the body's limbs and organs.
Divided into:
- Somatic nervous system: Manages voluntary movements and sensory reception.
- Autonomic nervous system: Controls involuntary functions, further categorized into sympathetic (fight-or-flight response) and parasympathetic (rest-and-digest response) systems.

Utilize various methods to investigate the electrical properties of neurons:
- Patch-clamp technique: Allows for the measurement of ionic currents through individual ion channels.
- Extracellular recording: Captures the electrical activity of multiple neurons simultaneously.

The nervous system is pivotal in maintaining homeostasis through feedback mechanisms that regulate essential bodily functions.

Common neurological disorders include:
- Epilepsy: Characterized by episodes of unusual electrical activity in the brain, leading to seizures.
- Parkinson’s disease: Results from the degeneration of neurons that produce dopamine, affecting motor control and coordination.
- Multiple sclerosis: Involves the destruction of the myelin sheath around neurons, impairing signal conduction.

Understanding neurophysiology is essential for insights into the functioning of the nervous system and for developing treatments for various neurological disorders.