Intro to neural control systems Flashcards
Where is grey matter found and what is its role?
Packed in dendrites
-Role is involved in processing information
Where is white matter found?
In bundles of axon
-This carries information to dendrites
What is the CNS composed of?
Spinal cord and brain
What do afferent nerves carry in the peripheral nervous system?
Afferent: carries information to brain
What do efferent nerves carry in the peripheral nervous system?
Efferent: carries (motor outputs): information from brain to effectors
(glands, skeletal/smooth muscles)
What is the somatic nervous system?
Includes all nerves that run to and from the spinal cord and send information to and from the muscles and senses
What is the autonomic nervous system?
Component of the peripheral nervous system that regulates physiological processes including heart rate, blood pressure, respiration, digestion and sexual arousal
What are the thinking parts of the brain?
Cerebral cortex and hippocampus are the thinking part of the brain
What connects the two hemispheres of the brain?
corpus callosum connects the two hemispheres – axons running through
What makes up the diencephalon?
divided into 4 main parts
-Epithalamus
-Thalamus
-Subthalamus
-Hypothalamus
What does the thalamus relay to and from?
Thalamus relays signal to and from the cerebral cortex
What do sensory pathways do in the thalamus?
Sensory pathways synapse in the thalamus on the way to the cortex
What is the hypothalamus the master controller of?
Hypothalamus is the master controller for homeostasis
What does the hypothalamus lihk and control?
Links neural and endocrine systems
-Controls the system that regulate the internal environment via the ANS and the systems that generate the sleep-wake cycle
What does the brainstem manage and via what system?
Manages visceral function via the autonomic nervous system
What does the brain stem work with to fine-tune motor control?
Works in partnership with cerebellum to fine tune motor control
What turns into the spinal cord as it extends beyond the skull?
The medulla turns into spinal cord as it extends beyond the skull
What does the spinal cord carry?
Carries afferent and efferent axons for somatic and autonomic nervous systems
What is the resting membrane potential?
The Resting Membrane Potential (RMP) is a potential difference between the inside
and outside of the membrane
What allows current flow across the nerve?
Potential difference allows current flow
How is the resting membrane potential generated?
- We use ATP to drive Na out of
cell and import K - 3 K in and 2 Na out – leaving
deficit of negative charge inside of
cell - This causes the formation of a concentration
gradient - More positive inside
momentarily - Allows opening of K channel
which allows K to flow out of the
cell via. diffusion due to
concentration created - More positive outside
charge inside a cell
- This gives the potential
difference - Na can’t flow back in
- You will get to a point where K
can no longer be diffused due to
build-up of positive charge - However, equilibrium can be
reached ~ -70mV which maintains the
RMP
What is the resting membrane potential?
-70mV
What is the size of the membrane potential determined by?
The size of membrane potential is
determined by size of concentration
gradient
What is the normal range of K in plasma
About 3-5mM
What can happen if K+ levels are altered?
If that changes e.g. kidney disease (hyperkalaemia), tissue damage – dead tissue
releasing K – it turns into medical emergency
o If concentration gradient gets smaller, then all membrane potential of cells
will get smaller too
o Can disrupt your neural activity
o Disrupt you heart activity
How do nerves depolarise?
- How to depolarise the cell – we
need positive charge into the cell - Na channels closed at rest but
when action potential fired it
opens (it is voltage gated meaning
it will open due to change in
membrane potential) – flows into
the cell - To bring back to rest you need to open
more K channels to allow K to flow out
the cell causing repolarisation - Then hyperpolarisation
What is the size of the synaptic cleft?
20-50nM between presynaptic and postsynaptic cell.
