Ch.2, Nervous System Anatomy

Question 1

Agenesis of the cerebellum symptoms, cognitive and motor; symptoms if it occurs in childhood

Answer 1

Failure of brain region to develop
Cerebellum contains 80% of the neurons in the human brain
Cerebellum does have higher cognitive functions which is unique for a lower brain region
Ataxia: failure of motor coordination: ataxia, distinctive speaking pattern, awkward gait, and difficulties with balance
Cognitive Difficulties: difficulty planning, abstract thinking, and language
Some of this agenesis did get better due to brain plasticity, in this case other structures likely helped out
If this occurs as a child, severe visuomotor deformities
Agenesis: failure of brain region to develop, very rare
Always functional connectivity: structures never operate independently

Question 2

Sensory input function of the nervous system

Answer 2

conduction of signals from sensory receptors to the CNS, all info coming into brain via the peripheral nervous system; sensory neurons carry info into the CNS

Question 3

Sensory neurons vs receptors

Answer 3

Sensory Neurons can act as both a receptor and carrying info
USUALLY Rods and cones (receptors) synapse with neurons

Question 4

CNS, (2) Integration

Answer 4

analysis and interpretation of the sensory signals and formulation of responses
OCCURS ONLY IN CNS, ALWAYS ARE WITHIN CNS ALL THE TIME spinal cord or brain
Interneurons carry out this function: usually means between, cells that exist in circuits with other neurons, but they are always in between
ALWAYS IN THE MIDDLE

Question 5

Motor Output, functions of the CNS

Answer 5

Not just motor output, can be output into organs
Coming out of CNS, going to periphery, to send to effector cells (like muscle cells, organs, glands)
Dendrites and cell bodies are in the CNS: AXONS AND AXON TERMINALS LEAVE THE CNS IN ORDER TO SYNAPSE WITH EFFECTOR CELLS

Question 6

Transduce/transduction:

Answer 6

one form of stimuli and converting it to another (stretch receptor: mechanical energy–converting it into chemical energy)

Question 7

Perception:

Answer 7

making sense of sensations and creating your subjective reality: NO ONE’S PERCEPTION IS THE SAME

Question 8

principle 9 of nervous system organization

Answer 8

The nervous system produces movement in a perceptual world that it constructs
Sensory organs convert info about the world (sensory stimuli) into biology activity; cellular and chemical processes that constructs perceptions = subjective reality
One reality is not better than the other, they are just different
Adaptations over time equip each species with a view of the world that enhances their reproductive success

Question 9

principle 10 of nervous system

Answer 9

Brain Is plastic
Neural tissue has the capacity to change in response to the world by modifying its organization
The more complex the brain = the more plastic it is
For example, the congenital blindness may result in increased higher

Question 10

Organization of nervous system

Answer 10

Central Nervous system: brain, spinal cord, retina
Peripheral Nervous System: somatic nervous system and autonomic nervous system, enteric nervous system
CNS: mediates behavior
SNS: transmits sensation FROM ALL SENSES, produces movement, cranial nerves, and spinal nerves, conscious (effector cells = skeletal muscles) muscles joints and skin
ANS: sympathetic division, parasympathetic division, unconscious, homeostasis, urination, heart rate, etc.
PART OF ANS, Sympathetic: fight or flight, arousal (effectors=organs and glands)
PART OF ANS, PSNS: opposite, calming, brings it to baseline, rest and digest (effectors=organs and glands)

Question 11

Dorsal/Superior, ventral/inferior, medial, lateral, anterior, posterior,

Answer 11

Dorsal/superior: up
Ventral/inferior; toward the floor
Medial: toward midline
Lateral: toward side
Anterior: front of face out
Posterior: back out

Question 12

Coronal section, horizontal section, saggital section

Answer 12

Coronal Section/ gives frontal view cut from vertical, get dorsal vs ventral and medial vs later, CANNOT GET ANTERIOR AND POSTERIOR
Horizontal Section Dorsal View: gNO DORSAL VS VENTRAL, can see anterior, posterior, medial, and lateral
Medial view/Saggital Section: typically looking at right hemisphere, dorsal, ventral, anterior, posterior BUT NO LATERAL OR MEDIAL

Question 13

Epsilateral vs contralateral

Answer 13

“EPSI” SAME SAME
“Contra” opposite side

Question 14

Bilateral representation

Answer 14

Hippocampus is bilateral: has a left and a right

Question 15

3 layers protecting the nervous system/brain (meninges)

Answer 15

(1) Durameter: hard mother, toughest layer
(2) Arachnoid membrane: mainly connective tissue, looks like a spiderweb
Subarachnoid Space: between arachnoid and pia mater, filled with cerebrospinal fluid
(3) Pia Mater: soft mother but still moderately tough, follows all the brains contours

Question 16

Symptoms and etiology of meningitis

Answer 16

Any type of infection can cause
Meninges get inflamed and press on brain
Symptoms: severe headache, stiff neck/head retraction, convulsion (last symptom only happens if brain starts to get damaged)
Treatment: antibiotics if bacterial
May result in long term consequences like deafness, epilepsy, cognitive deficits
Pitekia rash: burst blood vessels looks like purple dots
Encephalitis: infection of the brain itself; different forms have different effects on the brain

Question 17

Rasmussen Encephalitis

Answer 17

attacks one cerebral hemisphere and requires a hemispherectomy (no known cause, shares some features of autoimmune disorders)

Question 18

Allocortex

Answer 18

Allocortex: evolutionarily older, made of hippocampus and amygdala

Question 19

Indentations vs bumps and ridges in the brain

Answer 19

Indentations in the brain: sulci (singular = sulci)
Bumps and ridges: gyri (gyrus, singular)

Question 20

Central sulcus

Answer 20

divides frontal lobe from parietal

Question 21

Lateral Fissure/Sylvian Fissure: f

Answer 21

forms the border of the temporal lobe

Question 22

S1:

Answer 22

in parietal lobe,primary somatosensory cortex = postcentral gyrus

Question 23

M1:

Answer 23

primary motor cortex, precentral gyrus, movements of individual muscles, frontal lobe

Question 24

Pyramidal cell

Answer 24

tear drop shape/triangular, predominant cell types of the cortex / primarily interneurons in the cortex

Question 25

Astrocyte:

Answer 25

star shaped, glial cell

Question 26

Gray matter:

Answer 26

outside, neocortex, made up of cell bodies, dendrites, and capillaries (pinkish grey bc of capillaries)

Question 27

Oligodendrocyte vs schwann cell

Answer 27

Oligodendrocyte: responsible for myelination in CNS
PNS: schwann cell responsible for myelination in the PNS

Question 28

Node of Ranvier

Answer 28

The nodes of Ranvier are the only sites along a myelinated nerve fiber that support the fast de- and repolarization process necessary for generation of action potentials.449

Question 29

Difference between nuclei and ganglia

Answer 29

Nuclei plural, nucleus single: IN CNS, tend to be buried pretty deep
Ganglia plura, ganglion plural: IN PNS

Question 30

Tracts vs nerves

Answer 30

Tracts: large collection of axons coursing together IN THE CNS
Nerves: OUTSIDE THE CNS ^^ fiber pathways carrying info from one point to another

Question 31

Location of the 4 ventricles

Answer 31

2 lateral ventricles: right and left, one in each hemisphere
3rd ventricle, in part of the brain stem
Fourth ventricle: base-most part of the hindbrain

Question 32

Cerebral aqueduct

Answer 32

Cerebral Aqueduct: canal that connects third and fourth ventricles, and sends cerebrospinal fluid down the spine

Question 33

Bidirectional flow of info in the brainstem

Answer 33

can flow bottom-up: spinal cord to cerebrum
can flow top-down: cerebrum downward

Question 34

Brainstem

Answer 34

evolutionarily oldest
begins where spinal cord enters skull
RECEIVES AFFERANT SIGNALS from the body’s senses; then sends efferent signals out to the spinal cord to control most of the body’s movements

Question 35

3 parts of the brain stem

Answer 35

Reticular formation: netlike mixture of nuclei and fiber pathways; nuclei are located in patches along its length: SLEEP WAKE BEHAVIOR, STIMULATES THE CEREBRUM, if damaged = coma
Pons: bridge between cerebellum and brain, vital body movements, breathing, relay between CEREBELLUM And brain
Medulla: cardiovascular system, breathing, relay between brain and spinal cord

Question 36

Cerebellum functions

Answer 36

movement timing and precision, motor learning, balance, posture, increases in size with the speed and dexterity of the species

Question 37

Midbrain, tectum and tegmenjtum

Answer 37

Tectum (roof): dorsal in humans, sensory structure, posterior, produces orienting movements (toward sound or other stimulus)
Tegmentum (floor); anterior in humans, ventral, species specific behaviors, perceptions of pain

Question 38

Three components of the diencephalon and functions

Answer 38

-thalamus: takes in info, sends it to the cerebrum, relay station, all sensory info is organized and integrated here
-Pituatary gland: master gland, hormone release
Hypothalamus: regulates hormone release from pituitary, sexual behavior, temperature regulation, eating, drinking

Question 39

Thalamus: Medial geniculate nucleus and lateral geniculate nucleus

Answer 39

The medial geniculate nucleus (MGN) and lateral geniculate nucleus (LGN) are the specific thalamic nuclei that relay the auditory and optic pathways, respectively

Question 40

3 parts of the forebrain

Answer 40

cerebral cortex, basal ganglia, olfactory bulbs

Question 41

Two parts of the cerebral cortex

Answer 41

neocortex: perception, planning, emotions, memory
allocortex: role in emotional and motivational states

Question 42

Two parts of the basal ganglia in forebrain

Answer 42

coordination of voluntary movements; collection of nuclei below the white matter of the cortex = made up of caudate nuclei and putamen

Question 43

Hippocampus

Answer 43

memory consolidation, crystallization, specifically autobiographical and episodic; one of the earliest and most severely affected structure in many disorders like Alzheimers

Question 44

Motor Cortex Layers

Answer 44

I, I, III: integrative functions
IV: sensory input, afferent
V: output to other parts of the brain (efferent), much larger in motor cortex
VI: output to other parts of the brain, much larger in motor cortex

Question 45

Striatem

Answer 45

includes the caudate nucleus and putamen

Question 46

Globus pallidus

Answer 46

). The primary function of the globus pallidus is to control conscious and proprioceptive movements.

Question 47

Organization of the somatic nervous system nerves from head down (4)

Answer 47

Cervical nerves
Thoracic nerves
Lumbar nerves
Sacral nerves

Question 48

Law of Bell and Magendie

Answer 48

structures that are posterior = almost always sensory
structure that are anterior= almost always motor

Question 49

Watermelon analogy of the forebrain/neocrotex

Answer 49

Extending our analogy between the brainstem and your forearm, imagine that the fist (the diencephalon) is thrust inside a watermelon — the forebrain, with the neocortex as the rind and the allocortex and basal ganglia as the fruit inside. Just as watermelons come in various sizes, so do brains, which in a sense is what evolution has done: the forebrain varies considerably in size across species.

Question 50

what is the neocortex composed of?

Answer 50

6 layers of grey matter that sit on the corpus collosum, which joins the two hemispheres

Question 51

dorsal vs ventral; streams

Answer 51

dorsal stream is unconscious, it is the where
ventral stream is concious, it is the what