Integration ( brain + spinal cord) Flashcards
What parts are involved in CNS
Brain and Spinal cord
What is the role of the brain and spinal cord in CNS
transmits signal to(sensory) and from(motor) the brain via ascending and descending tracts and it combines and excutes somatic and autonomic responses
What are Reflexes
it is a rapid and automatic response ot a stimuli and usually its for protection
uses 2 or more neurons and stimuli always causes same motor response
What is the reflex pathway or arc
it is the pathway of impulses
(stimulus=> R => CNS => E(effector)
Reflexes are catergorized by
- Types of effector ( somatic or visceral)
- Which sides of the body the sensory and motor neurons are located (Ipsilateral or contralateral)
- # of synapses in a reflex arch(monosynaptic or polysnaptic)
What is the difference between somatic and visceral
somatic reflex has the skeletal muscle as it’s effector
Visceral Reflex has the smooth muscle, cardiac muscle or glands as it’s effector
What is the difference between Ipsilateral and contralateral reflex
Ipsilateral has sensory and motor neurons on the same side
Contralateral has sensory and motor neurons on the opposite sides
What is the difference between monosynaptic and polysynaptic
monosynaptic has 1 sensory and 1 motor neuron
Polysynaptic ahs 2 or more synapses between 3 or more neurons
examples of a somatic spinal recflex
Stretch reflex, Flexor Reflex and Crosses Extensor Reflex
What is a stretch reflex and examples of it (which side and how many synapses
automatic muscle contraction in response to sudden or excessive stretching
Ex. knee Jerk (extensor muscle contracts)
S: tapping patellar ligament
R:Muscle Spindle
E: Skeletal muscle contradicts
Ipsilateral and monosynaptic
What is Flexor reflex and it’s example
( which side and how many synapses)
automatic reaction of flexor muscle that moves part of body away from painful stimulus
S: Stepping on nail
R: touch, pressure, pain
E: hamstring contracts
Ipsilateral and polysnaptic
What is a Crossed Externsor reflex and it’s example (which side and how many synapses)
automatic contraction of extensor muscle in the opposite limb during a withdrawal reflex (balancing+supporting)
S:stepping on nail
R:touch, pressure and pain
E: Quadriceps Femoris in opposite leg contracts
Contralateral, polysynaptic
What is Reciprocal Inhibition and example
When one muscle contracts, muscle on opposite side of joint (antagoinist) relaxes to allow smooth and efficient movement
Stretch flex: quad femoris (agonist) contracts, hamstring(antagonist) relaxes
Example of Autonomic spinal reflexes and what are the effectors
E: smooth muscle, cardiac muscle or glans
Ex.Micturition(urinary bladder)
S:Strech of bladder
R: stretch receptors in bladder wall
E: detrusor muscle (wall of bladder) contracts while urethral sphincter opens ( both smooth muscle)
What parts of the brains are involved in integration and control
- Cerebrum
- Brain Stem ( Midbrain, pons, medulla)
- Hypothalamus
What is the main function of the cerebrum
- interprets sensory info and start and control skeletal muscle movements
-higher function: memory, intellect, language and emotional regulation
-relays info between different parts of brain to or from the spinal cord
What is the main function of the brain stem
controls life sustaining processes like breathing
If brain stem is function, but higher centres are damaged, what happens
person would be physiologically alive but would not be aware or have conscious control
What is the main function of the midbrain
handles the auditory and visual reflex
What is the main function of the pons
work together with medulla to regulate breathing
What are the vital areas of the medulla and what does it do
- Decussation ( crossing) of sensory and motor tracts
( left brain controls right skeletal muscle = recieves sensory input from right side) - Autonomic Vital Reflex Centre
Respiratory: drives breathing rate
Cardiovascular Areas: cardiac - modifies heart rate and vasomotor controls blood vessel diameter - non vital areas: control swallowing, coughing, sneezing and vomiting
What are the main functions of the hypothalamus
- Regulate ANS, parts of endocrine system, temperature, food and water intake=body fluid concentration
- Regulate emotion in limbic system
(cerebrum, thalamus and hypothalamus) - Regualate your wake up time in the reticular activating system
What parts of the brain controls all major homeostatic functions and what happens if it is damaged
Hypothalamus and if it is damaged, it can cause loss of homeostasis
