L1 anatomy Flashcards
What forms the central nervous system (CNS)?
The brain together with the spinal cord and the cranial nerves
What does the central nervous system control?
Both conscious and unconscious functions of your body
What did the “Treatise of Man” by Rene Descartes say about nerves?
Nerves are hypothesized to be conductors of information from the skin and sense organs to the brain and back from the brain to the muscles
What has the central nervous system evolve into?
A device made of nerve cells that processes information to convert sensory input into appropriate motor output
Which part of central nervous system is oldest?
Spinal cord
How does the spinal cord takes in information?
From sensory neurons from the dorsal nerve roots and sends information back out through nerves at the ventral roots
What will happen if there is a sudden tap on the patellar tendon?
The quadriceps muscle will be stretched
What is sensory stretch receptor neurons’ name in patella reflex?
Dorsal root ganglion cells
Where does the sensory stretch receptor neurons connect to in patellar reflex? And what is their effect?
Motor neurons in the ventral horn of the spinal cord. The motor neurons will cause the quadriceps muscle to contract
What innervates the hamstrings to relax in patellar reflex?
Inhibitory interneurons in the ventral horn
What is the other name for simple neural circuit?
Monosynaptic
What does patellar reflex help with?
Postural adjustment
Name a complex reflex.
Withdrawal reflex
Name a neural control structure.
Central pattern generators which produce rhythmic locomotive movement
What is the general pattern of organization that is applicable to reflex arcs and brain? (input and output)
Sensory information enters the CNS at the back and motor outputs are computed and sent out to the front
What are afferents?
Nerve cells which carry information toward higher processing centres
What are efferents?
Nerve cells which carry signals toward motor output structures
How the brain has evolved?
By layering more and more complex input-output loops on top of existing ones
How did Charles Sherrington imagined all brain function?
Potentially huge complex, interlinked and hierarchically organized reflex arcs that interact
What did the brain researchers think Sherrington’s view underestimated?
The importance of innate drives and long term memories in shaping perception and motivation
Name the multiple circuits that serve visual purpose.
Older: Superior colliculus (optic tectum)
Newer: Visual cortex
Name the multiple circuits that make people move.
Spinal chord reflex arcs and cerebellar and motor cortical circuits
Are the multiple circuits active in parallel?
Yes
What are brain’s circuits made of? And how many of them in one human brain?
Nerve cells (neurons). 100billion.