Anatomy - CNS Flashcards
What are the 4 divisions of the Brain?
Cerebrum, Diencephalon, Brainstem, Cerebellum
What is the Function of the Cerebrum?
Higher cognitive functions, sensory perception, voluntary motor actions, and emotions
What is the Function of the Diencephalon?
Includes the thalamus (sensory relay), hypothalamus (homeostasis and endocrine control), and epithalamus (sleep/wake cycle).
What is the Function of the Brainstem?
Basic life functions like heart rate, breathing, and reflexes.
What is the Function of the Cerebellum?
Balance, fine motor movements (smaller scale movements such as typing or writing)
What parts of the brain does the Brainstem consist of?
Midbrain, pons, and medulla oblongata
What is White Matter & Where is it Located?
Contains myelinated axons for transmitting signals.
Found deep in the brain (beneath gray matter) and in the outer spinal cord.
What is Grey Matter & Where is it Located?
Contains neuron cell bodies, dendrites, and unmyelinated axons.
Found on the surface of the brain (cerebral cortex) and in the inner spinal cord.
Why do we have Gyri and Sulci?
Increase the surface area of the cerebral cortex, allowing more neurons to fit in the limited space of the skull.
This ENHANCES cognitive processing.
What is the function of cerebrum gray matter areas?
Motor Areas: Control voluntary movements
(ex: Primary Motor Cortex).
Sensory Areas: Interpret sensory information
(ex: Primary Somatosensory Cortex).
Association Areas: Integrate and interpret information
(ex: Prefrontal Cortex for decision-making).
What is the Primary Motor Cortex?
Controls voluntary movements of specific body parts.
What is the Primary Somatosensory Cortex?
Processes sensory input from specific body parts.
What steps and areas are involved in carrying out a motor action?
- Basal Nuclei: Initiate and regulate movement.
- Motor Cortex: Sends commands to execute movements.
- Cerebellum: Refines movements for precision and balance.
- Spinal Cord: Transmits signals to peripheral nerves.
- Neuromuscular Junction (NMJ): Motor neurons release acetylcholine, causing muscle contraction.
What is the function of the Basal Nuclei?
Regulate voluntary motor movements
What is the function of the Limbic System?
Involved in emotions, memory, and behavior.
What is the function of the Thalamus?
Acts as a sensory relay station, receiving sensory input (except smell) and sending it to the cerebral cortex.
What is the function of the Hypothalamus?
Regulates homeostasis by controlling body temperature, hunger, thirst, and the endocrine system (via the pituitary gland).
What is the function of the Meninges?
Three protective layers that protect and are around the brain and spinal cord:
Dura Mater: Tough outer layer.
Arachnoid Mater: Middle layer with a web-like structure.
Pia Mater: Thin inner layer directly covering the brain and spinal cord.
What is the function of Cerebrospinal Fluid (CSF)?
Cushions the brain and spinal cord, provides nutrients, and removes waste.
What is the function of the Blood-Brain Barrier (BBB)?
Protects the brain by restricting harmful substances from entering while allowing essential nutrients to pass.
Primary Sensory Area vs Association Area
Primary Sensory Area receives and processes initial sensory input from the body.
Association Area interprets and integrates THAT INPUT to give it meaning.
What is the Amygdala? (Substructure of the Cerebrum)
Plays a role in behavioral/emotional expression.
What is the Hippocampus? (Substructure of the Cerebrum)
In charge of memories.
What is the Pons? (Part of Brainstem)
Key role in regulating breathing, relaying signals between the cerebrum and cerebellum, and aids in sensory analysis.
What is the Midbrain? (Part of Brainstem)
Found in uppermost part of the brainstem
Involved in Reflexes and movement coordination
How is a signal sent to tell a muscle in your hand to contract?
- Brain: The motor signal starts in the primary motor cortex.
- Spinal Cord: It travels down the spinal cord to a motor neuron.
- Peripheral Nerve: The signal reaches the peripheral nerve that innervates the muscles of the hand.
- Muscle: The motor neuron releases acetylcholine at the neuromuscular junction, which binds to to the muscle fiber, triggering an action potential, causing the muscle to contract.
