Subcortical Structures

What are the subcortical structures responsible for?

primitive functions

Where are the subcortical structures?

below the level of the cortex

What are the subcortical structures?

-brainstem
-basal ganglia
-cerebellum
-thalamus
-hypothalamus
-hippocampus

What is the evolutionarily the oldest part of the brain?

Brainstem

What does the brainstem connect?

-connects spinal cord to subcortex and cortex

What are the three main parts of the brain stem?

-midbrain
-pons
-medulla

What is the most superior section of the brainstem?

midbrain

What does the midbrain house?

substantia nigra

What disease does the midbrain play a large role in?

Parkinson's disease

What does the substantia nigra do?

produces dopamine

What is the middle structure of the brainstem?

pons

What does the pons connect?

connects the cerebellum to the rest of the brain

What does pons mean?

bridge

the pons is a ______ _____

relay station

What is the most inferior part of the brainstem?

medulla

What does the medulla connect too?

spinal cord

What happens with the spinal nerves at the medulla?

point of decussation from spinal nerves

What is the medulla in charge of?

lower-level functions:
-Heart Rate
-breathing
-vomiting
-blood pressure

Where is affected with alcoholism?

medulla

What percentage of the nerves decussate?

80%

Where do the nerves decussate?

-the decussation of pyramids
-in between medulla and spinal cord

What are the three main parts of the basal ganglia?

-caudate nucleus
-putamen
-globus pallidus

What is the function of the basal ganglia?

-regulates muscle tone
-role in motor learning
-takes unnecessary or extra movements out of motor plan

What is motor learning?

tells how far to extend arm and how much pressure to apply to the object

What are some examples of disorder or diseases that the basal ganglia is affected in?

-dysarthria
-Huntington's disease
-Parkinson's disease

What is the cerebellum also called?

-little brain
-error control device

Why is the cerebellum also called the error control device?

makes adjustments to motor plan to meet objective

What is the function of the cerebellum?

-Scales and coordinates movements
-equilibrium

What are some scales and coordinates movement?

Regulates speed, size, etc.

The cerebellum is highly impacted by _____________ ___________

alcohol consumption

The cerebellum fine tunes all ___________

movements

The ______________ _______ sends a signal to the cerebellum

semicircular canals

What smoothens all the movements?

-cerebellum
-basal ganglia

What is the thalamus?

-sensory relay station (cold, pain)
-all afferent signals (except olfactory) pass through

Where is the olfactory being processed at?

olfactory bulb

Where is the hypothalamus?

-below the thalamus
-above pituitary gland

What system is the hypothalamus highly involved with?

endocrine

What is the function of the hypothalamus?

-regulates the pituitary
-Controls many autonomic functions:
Reproductive behavior
Thirst & hunger
Metabolic function
Some impact on emotion

Where is the hippocampus?

deep to the temporal lobe

What is the function of the hippocampus?

memory function

Alzheimer's greatly affects the __________

hippocampus

What is the primary functional unit of the brain?

neuron

What are neurons?

-cells within nervous system
-communicating tissue

Neurons can be ___________ or ___________

excited or inhibited

What are the main parts of the neuron?

-dendrite
-soma (cell body)
-axon

What do dendrites do?

brings in information into the cell body

What do axons do?

take information away from the cell body

How do neurons communicate?

-The neurons communicate with one another via a synapse
-an action potential is generated in the cell body.
-This action potential travels fast along the axon.
-Once the action potential reaches the axon terminal, it releases a neurotransmitter e.g. acetylcholine.
-The dendrites of the other neurons contain receptors for this neurotransmitter.
-If the signals received from the first neurons are sufficiently strong
-the action potential is transmitted through the dendrites of another neuron

What are the types of neurons?

-motor neurons
-interneurons
-sensory neurons

What are motor neurons?

motor plans from brain to muscles

What are interneurons?

communicate with other neurons

What are sensory neurons?

messages from sensory receptors to brain and spinal cord

What are the two main types of motor neurons?

-upper motor neurons
-lower motor neurons

What are the different types of the neurons in the nervous systems?

-UMN-CNS
-LMN-PNS

The neural pathway goes from the _____ to _____

UMN, LMN

What do glial cells support?

surrounding neurons

What are the types of the glial cells?

-Schwann cells
-oligodendrocytes
-microglia
-astrocytes
-ependymal cells

What do Schwann cells do?

build myelin in PNS

What do oligodendrocytes do?

build myelin in CNS

What does microglia do?

remove dead cells and waste

What do astrocytes do?

-line blood vessels
-regulate transmission of substances across vessels
-form scar tissue in brain

What do ependymal cells do?

line the ventricles (CSF)

What does myelin do?

-insulates the axons of neurons
-conducts message much quicker

What is myelin made by?

Made by oligodendrocytes and Schwann cells