Unit 5: nervous system Flashcards
CNS organs. And is composed of what
Brain and spinal cord
Composed of grey and white matter
Grey vs white matter
- Unmielinated, have cell bodies, dendrites, axon terminals, glial cells
Involved in integration of info
- Axons of myelinated neurons and glial cells (fills up space)
Involved in info transmission from 1 location in cns to another
Forebrain: cerebrum (features and major components)
Left and right cerebral hemispheres
3 major components
Cerebral cortex (grey matter)
Tracts (white matter)
Basel nuclei
Forebrain: diencephalon (features)
Thalamus
Hypothalamus
Midbrain: superior vs inferior colliculi
1 visual reflexes
2. Auditory reflexes
Midbrain: posterior/dorsal portion
Tegmentum
Cerebral peduncles
White matter tracts that carry motor info from the cortex to spinal cord
Hind brain: features
Cerebellum: involved in balance and movement
Pons
Medulla oblongata
Spinal cord: dorsal, ventral, and lateral horn
- Grey matter- cell bodies of interneurons
- Grey matter- cell bodies of lower motor neurons and interneurons
- Grey matter- Cell bodies of preganglionic neurons
Spinal cord: ascending and descending tracts
Both white matter
1. Carry sensory info to the brain
2.carry signals of brain to somatic and autonomic motor neurons
Protective features cns: what is brain and spinal cord encased in
Brain encased in skull, spinal cord encased in vertebral column
Dorsal root ganglion
1Cell bodies of sensory neurons
Ventral root vs dorsal root
Axons of motor neurons that carry signals away from the spinal cord to muscle and gland effectors
2 axons of sensory neurons that carry signals into spinal cord
Connective tissues that surround brain and spinal
Meninges
Meninges 3 layers (dura, arachnoid, cerebrospinal)
- Outermost layer (2 fused layers of tissue in brain- only one layer in spinal)
- Middle layer- spider web like strands that connect to pia matter (3rd layer)
- Innermost, direct contact w/ brain and spinal
What does dura matter (most outer layer tissue in brain/spinal) form
Dural venous sinuses - which drains blood and fluid away from brain
What is meningitis and cause. What happens to brain
Inflammation of the meninges
Caused by viral infection that
enters the cerebrospinal fluid
Will put pressure on the brain or spinal which can be damaging to the neural tissue
What is intracranial haemorrhage and caused by
Brain bleeds- caused by head injuries
Cerebrospinal fluid (CSF) (where is it found & what are they)
Surrounds brain and spinal cord
Also found in ventricles of the brain and central canal of spinal cord
Ventricles= hallow portion/spaces of brain filled w/ csf (hallow from remains of neural tube)
Central canal= space/channel filled w/ csf that passes through the middle of the spinal cord
Choroid plexus
Capillaries in contact w/ transport epithelium
Epithelium
Simple cuboidal made of ependymal cells
Transcellular vs paracellular transport
- Solutes move across
- Solutes move between
Csf goals
Help remove waste from neural tissue
Protects neural tissue
Help maintain solute concentration in isf surrounding neurons
Blood brain barrier (bbb) where is it found and how is it formed. Function for brain
Throughout brain except hypothalamus
Formed from processes of astrocytes
Protects brain from toxic water soluble compounds
What can cross bbb
Very small or lipid soluble (hydrophobic, lipophillic) molecules
What is grey matter in spinal cord divided into
Horns
Dorsal, ventral, lateral horn
Dorsal horn
Axon terminals and cell bodies of somatosensory neurons (touch, temp, pain, pressure)
Spatial reflex arc pathway
- Receptor
- Unipolar sensory neuron
- Integration centre
- Motor neuron
5, effector/target
Cerebrum grey matter: central cortex
Conscious brain- responsible for thoughts, voluntary movements and memories, etc
Cerebrum grey matter: basel nuclei (or basel ganglia)
Assist in control of movement, surpass unwanted movement at rest
Cerebrum grey matter: limbic systems
Emotional brain- fear, flight or fight,
Limbic system includes: amygdala
Emotion and memory - ties to emotional meaning
Limbic system includes: cingulate gyrus
Processing of emotions and regularion of behaviour
Limbic system includes: Hippocampus
Learning and memory (sensory memories- ex: smelling cookies reminds you of grandma’s house
Cerebrum white matter: association tracts
Transmit AP from one area of cortex to another within same hemisphere
Cerebrum white matter: commissural tracts
Transmit Ap from one area of cortex to another in opposite hemispheres
Cerebrum white matter: projection tracts
Run vertically from cortex to connect to deeper areas of the brain
The 5 lobes: frontal, temporal, parietal, occipital, and insula lobe
- Motor areas
- Special senses (auditory and olfactory)
- General senses
- Special senses (vision)
- Special senses (taste)
cerebrum: Broca’s area and Wernicke’s area
motor speech
both on left side
Left hemisphere contains areas responsible for:
language and verbal (speech) skills
ii. mathematical skills
iii. writing skills
right hemisphere
spatial visualization and analysis by touch.
(often associated with artistic functions)
ii. processing and recognition of emotions
iii. emotional components of language –
tone of voice, gestures
iv. facial recognition
Damage to Wernicke’s area
Receptive Aphasia
Can speak, but words are mixed up or meaningless because
the person is not able to connect words with their meaning.
Speech is described as a non-sensical “word salad”
damage to broca’s area
Can understand words and their meaning, but person is not able to
produce speech and has difficulty expressing ideas. Hard to get the
words/sentences out due to issues with motor control.
Thalamus
Sends and receives information to/from almost every area of the CNS
hypothalamus
regulates the body’s homeostasis (normal systematic functioning) and stimulates productions of hormones.
Cerebellum
Helps to plan, initiate and coordinate voluntary movements involving skeletal muscles
controls eye movement, balance
Midbrain
superior and inferior colliculi are involved in
movement of eyes (visual) head and neck in response to visual and auditory stimuli
For example: if you are in a classroom writing a test and
there is a loud noise – everyone looks up from the test to
see what is happening
Pons
regulate breathing
handles unconscious processes and jobs, such as your sleep-wake cycle and breathing
Medulla oblongata
the connection between the brainstem and the spinal cord
vegetative state
If the brain stem is functional but higher brain centers (cerebrum) are damaged, a person is alive but has no
conscious control
locked in syndrome / cerebromedullospinal disconnect
person is conscious and fully aware, but is fully paralyzed due
to damage to motor tracts running through anterior portions of
pons/medulla
