Wk 2 Neuroanatomy and Neurophysiology Flashcards

Flashcards about Neuroanatomy and Neurophysiology

Neurons

Nerve cells that send messages all over the body, connecting sensory messages from the environment to the brain and motor outputs.

Dendrites

Tree-like extensions from the neuron that receive electrical impulses from other neurons and convey them toward the cell body.

Nucleus

Located in the cell body, it houses the neuron's genetic material and controls the cell's activities. It contains the nucleus and other organelles, maintaining the neuron's health and functionality.

Cell Body

Also known as Soma, it is the cell body of a neuron .

Axon

A long, thin extension that transmits electrical impulses away from the cell body to other neurons or effector cells.

Myelin Sheath

Formed by Schwann cells, it insulates the axon to speed up the transmission of electrical impulses.

Node of Ranvier

Gaps in the myelin sheath that facilitate rapid conduction of nerve impulses along the axon.

Axon Terminals

Endpoints of the axon that release neurotransmitters to signal the next neuron.

Astrocytes

Provide structural support, regulate ion and neurotransmitter levels, and contribute to the blood-brain barrier.

Microglia

Act as immune cells in the central nervous system, defending against pathogens and participating in the removal of damaged cells.

Ependymal cells

Line the cavities of the brain and spinal cord, producing cerebrospinal fluid and assisting in its circulation.

Oligodendrocytes

Produce myelin, a fatty substance that insulates axons in the central nervous system, facilitating faster nerve impulse transmission.

Satellite cells

Provide support and nourishment to nerve cell bodies in the peripheral nervous system (PNS).

Schwann cells

Produce myelin in the peripheral nervous system (PNS), aiding in the insulation of axons and promoting efficient nerve signal transmission.

Glial cells

Cells in the nervous system which provide support and protection to the neurons.

Blood-Brain Barrier (BBB)

A highly selective semipermeable membrane that separates the circulating blood from the brain's extracellular fluid, regulating the exchange of substances and maintaining a stable environment for nerve function.

Synapse

A region where a neuron communicates with its target cell.

Synaptic cleft

The space between the cells

Neurotransmitters

The chemical signals which enable communication between neurons and other cells by enhancing (excitatory) or dampening (inhibitory) activity.

Acetylcholine

Essential for muscle activation and involved in learning and memory processes

Glutamate

Acts as the main mediator of excitatory signals in the brain and is crucial for synaptic plasticity, which is related to learning and memory

GABA (Gamma-amino butyric acid)

Functions as the primary inhibitory neurotransmitter in the brain, regulating neuronal excitability and maintaining a balance with excitatory stimuli

Serotonin

Regulates mood, appetite, and the sleep cycle, and also plays a role in cognitive functions like memory and learning

Dopamine

Mood regulation, reward processing, motor control, and learning. Motivation, pleasure and reinforcement in the brain

Norepinephrine (noradrenaline)

“Fight or flight” response, enhances alertness, attention, arousal. Influences mood. Contributes to blood pressure regulation

Epinephrine (adrenaline)

Release by the adrenal glands in response to stress. Triggers the “fight or flight” response. Increases heart rate, redirects blood flow, and mobilizes energy stores for rapid response to perceived threats.

Catecholamines

Class of neurotransmitters crucial roles in the central and peripheral nervous system

Central Nervous System (CNS)

Includes the brain & spinal cord; the control center for the entire nervous system that processes and interprets sensory information, initiates motor responses, and performs higher cognitive functions.

Peripheral Nervous System (PNS)

Composed of the structures outside of the CNS including the cranial nerves, spinal nerves and their distal branches, ganglia and receptors. Responsible for transmitting sensory information from the body to the CNS and carrying motor commands from the CNS to the body.

Brain stem

Consisting of the medulla, pons and midbrain

Frontal Lobe

Oversees executive functions like planning, controls voluntary movements, regulates personality and social behavior, houses Broca's Area crucial for speech, and is involved in cognitive functions such as working memory and planning.

Parietal Lobe

Processes sensory information, determines body position in space, includes the somatosensory cortex for touch sensations, coordinates input from different senses, initiates voluntary movements through the primary motor cortex, and contributes to awareness of body parts and their movements.

Temporal Lobe

Processes sound in the auditory cortex, forms long-term memories, comprehends language in Wernicke's area, contributes to emotional responses and social cognition, has some involvement in visual processing, and the hippocampus is critical for forming new memories and spatial navigation.

Occipital Lobe

Interprets visual information in the primary visual cortex, distinguishes colors and shapes, identifies objects and faces, and assists in perceiving depth and spatial relationships.

Primary motor cortex

Allows conscious control of precise, skilled, voluntary movements

Pre-motor cortex

Controls learned, repetitious, or patterned motor skills

Pre frontal cortex

Involved in higher cognitive functions such as decision-making, problem-solving, planning, and social interactions.

Somatosensory cortex

Receives sensory information from the skin, skeletal muscles, and joints. It is capable of spatial discrimination

Basal Ganglia

A group of nuclei (bundle of nerve cells) that are located in the subcortical region of the brain i.e., below the cortex. The basal ganglia are responsible primarily for motor control, as well as other roles such as motor learning, executive functions and behaviors, and emotions.

Spinal Cord

A long, cylindrical bundle of nerve tissue that extends from the brainstem, and runs down through the spinal canal within the vertebral column (spine) to the lower back. Transmits signals, reflexes and coordination of movement

Dermatomes

Regions of sensory information supplied by single spinal nerves that detect information such as pain, temperature, touch, pressure and vibration.

Ascending pathways

Carry sensory information to the brain, allowing us to perceive and interpret stimuli.

Descending pathways

Transmit motor commands from the brain to the body, enabling purposeful movements and coordinated actions.

Neuroplasticity

The ability of the brain to reorganize and modify itself is known as neuroplasticity.

Synaptic Plasticity

Changes in the strength and efficiency of communication between neurons at the synapses, improving signal transmission.

Structural Plasticity

Physical changes in brain anatomy through the formation of new neural connections or the pruning of old ones, allowing adaptation and recovery.

Somatic Nervous System (SNS)

Conscious control of skeletal muscles

Autonomic Nervous System (ANS)

Involuntary control & regulates smooth muscle, cardiac muscle, and glands. Regulates internal organs and maintains homeostasis.