The CNS Flashcards
What two things make up the Central Nervous Sytem?
The Brain and Spinal Cord
What is the CNS? What happens when it gets damaged? TMH
The B &SC -the main control centre for the nervous system
Coordinates all the mechanical and chemical actions
Receives info from the senses to process and initiate a response
Damage can effect
Temperament
Motor Control
Homeostasis (balance) (eg. Mad Cow Disease)
What are the two types of tissue in the CNS?
Grey (unmyelinated)
White (myelinated)
What is Grey Matter? Why is it Grey?
It’s grey because it contains mostly cell bodies, dendrites and short unmyelinated axons
Found outside areas of the Brain and form the H-shaped core of the spinal cord
What is White Matter? Why is it White?
It’s White because it contains myelinated axons that run together in tracts
Forms the inner region of parts of the brain and outer areas of the SC
Spinal cord specs
Vital for communication between the brain and CNS
Starts at brain, ends at tailbone
Sensory nerves carry messages for the body to the brain and vice versa
Primary reflex centre for neural information
Has white and grey matter
It’s tissues are protected by Cerebrospinal Fluid, soft layers and the spinal column
Damage can cause paralysis
Brain specs
Central role in maintaining homeostasis
Very fragile organ - protected by skull and the meninges
Meninges (3 layers of tough, elastic tissues within the skull and spinal column)
What is the Blood-Brain Barrier?
A membrane that separates blood and the CNS
Protects the brain, and gives it nutrients and oxygen
Lipid soluble substances (ie caffeine, drugs, nicotine etc.) can pass through the lipid bilayer
What does Cerebrospinal fluid do?
It circulates through the spaces (ventricles) within the brain and spinal cord
Transports hormones, WBCs & nutrients across the B-B-B for the brain cells
What are General regions of the brain?
Hindbrain
Mind rain
Forebrain
Parts of the Hindbrain CMP
Cerebellum
Medulla Oblongata
Pons
Cerebellum “little brain” UcopRBm
Walnut shaped
Located below and behind cerebrum
Controls: unconscious coordination of posture, reflexes and body movements
Also controls: fine, voluntary motor skills (ie. hitting a tennis ball, riding a bike, writing etc.)
Receives info from specialized sensors (proprioceptors) in the skeletal muscles and joints
Medulla (Oblongata)
Located at the of the Brain Stem
Connects the brain with the spinal cord
Centers that control automatic, involuntary responses (ie. Heart rate, constriction/dilation of blood vessels, rate/depth of breathing, swallowing, coughing)
Pons
Located above and in front of the Medulla (in the brain stem)
Relay centre between the neurons of the right & left halves of the cerebrum, cerebellum and the rest of the brain
What makes up the Brain Stem?
The Medulla, Pons and Midbrain
Midbrain
Located above the pons in the brain stem
Relays visual & auditory info between the areas of the hindbrain & forebrain
Important role in eye movement and control of skeletal muscles
Parts of the Forebrain (drugs)
Thalamus
Hypothalamus
Cerebrum
Thalamus specs
Known as the “great relay station”
Located at the base of the forebrain
Made up of the neurons that provide connections mainly between the forebrain & hindbrain and the sensory system & cerebellum
Hypothalamus specs
Located below the Thalamus
Regulate body’s internal environment and some aspects of behaviour
Neurons that control blood pressure, heart rate, body temp. And basic drives (thirst and hunger)
Also controls emotions (fear, rage, pleasure)
Link between nervous system and endocrine system (hormones)
Coordinated actions of the pituitary gland (making/releasing hormones)
Cerebrum (IMCL)
Makes up more than 4/5ths of the brain weight
It is divided into right and left cerebral hemispheres
Contains centers for intellect, memory, consciousness and language
Interprets and controls response to sensory information
Ex. Feelings of Hot and Cold
Relays visual & auditory info between the Hindbrain and Forebrain
Largest most highly developed area
Cerebral Cortex - the covering of grey matter on the outside of the cerebral hemispheres (left and right halves)
Responsible for language, memory personality, vision, conscious thought and activities associated with thinking/feeling
What is the Corpus Callosum?
It links the hemispheres by a bundle of white matter and sends info from one hemisphere to the other (neurons)
Right Brain specs
Responsible for holistic, intuitive thinking, visual spatial skills and artistic abilities, more creative
Left Brain specs
Responsible for the segmental sequential and logical ways of thinking as well as the mathematical and linguistic skills
Occipital Lobe specs
Located at the back of the brain, above the cerebellum
Receives and analyses visual info.Recognizes what is being seen
