Neuroscience Chapter 7

evolution acts on genes that are expressed during

development

anterior

front, towards the face

posterior

behind, towards the back

superior

above, toward the head

inferior

below, towards the feet

medial

towards the middle

lateral

towards the edge (extremities)

dorsal

toward the top of the brain/back of the spinal cord

ventral

toward the bottom of the brain/front of the spinal cord

rostral

towards the front of the brain/top of the spinal cord

caudal

toward the back of the brain/bottom of the spinal cord

forebrain

telencephalon - cerebrum

diencephalon - thalamus and hypothalamus

main parts of the mammalian CNS

• cerebrum

• diencephalon

• brain stem

• cerebellum

• spinal cord

spinal cord function

conducts information between the brain and body

dorsal root

sensory (afferent) towards CNS

ventral root

motor (efferent) away from CNS

CNS

brain and spinal cord

PNS

cranial nerves and spinal nerves

somatic PNS

innervates skin, joints, and muscles

visceral PNS

innervates internal organs, blood vessels, and glands

blood brain barrier is made up of

1. tight junctions between endothelial cells

2. astrocytes

meninges are

membranes surrounding the CNS

what are the 3 types of meninges

dura mater - tough

arachnoid - spider like

pia mater - delicate

cerebrospinal fluid (CSF)

keeps brain buoyant, cushions brain, maintains homeostasis, neuroendocrine signaling, turns over 3-4x daily

where is CSF made

choroid plexus, filters blood

how does CSF leave the brain

resorbed from the subarachnoid space by arachnoid villi

where do the brain ventricles and the central canal of the spinal cord originate during development

the lumen of the neural tube

neural tube gives rise to the _____ and the neural crest gives rise to the ________

CNS, PNS

how is the neural tube created

fusion of neural folds

anencephaly

the neural tube does not fold together on the rostral end

spina bifida

the neural tube does not fold (zip up) completely on the caudal end

what are teratogens

cause major disruptions in organogenesis

teratogen examples

thalidomide - disrupts limb formation

alcohol

radiation

When is the critical period for teratogens in human development

2-10 weeks post-fertilization

what does the cerebrum contain

neocortex, cerebral hemispheres, olfactory bulbs, basal ganglia, hippocampus etc…

the thalamus is responsible for

sensory processing

the hypothalamus is responsible for

governing the autonomic nervous system, visceral control

forebrain structures

cerebral cortex, thalamus, hypothlamaus, and basal telencephalon

white matter structures

corpus callosum, cortical white matter, internal capsule

forebrain structure/function

contains neocortex, analyzes input, commands motor output, communication between thalamus and cortex

thalamus

gateway to cerebral cortex, sensory processing (except olfaction)

tectum

orient eyes and body towards stimuli, superior colliculis (visual), inferior colliculus (auditory)

tegmentum

control of voluntary movement, wakefulness/mood. neurons appear pigmented(red, substantia nigra)

dorsal root ganglion consist of

neuronal cell bodies along the spinal cord. Carry sensory information.

the nervous system originates from the_________ during development

ectoderm

what is the neocortex responsible for

perception, cognition, motor planning

what are the basal ganglia responsible for

execution and initiation of movements

hippocampus

memorization and memory consolidation

what is the pons responsible for

bridge of axons connecting cortex

what is the cerebellum responsible for

sensorimotor coordination, skilled movements

what is the medulla responsible for

janitorial functions (HR, BP, RR)

what is the spinal cord responsible for

reflexes, convey information between body and brain

MRI (magnetic resonance imaging)

Hydrogen atoms align in a strong magentic field, pertrubed by radiowave pulses. Constructs a 3d model of the brain using

fMRI (functional magnetic resonance imaging)

1-2 mm resolution, identifies brain regions responsible for a certain task, changes in blood flow and metabolism

what brain structures are present 3 week post-conception

forebrain, midbrain, hindbrain, spinal cord

what brain structures are present 5 weeks post-conception

telencephalon, diencephalon (F) mesencephalon (M) metencephalon, myelencephalon (H) spinal cord

the nervous system comes from the

ectoderm (the outermost layer) during embryonic development

differentiation

process where structures become more specialized and complex from one another

diencephalon gives rise to

the retina and the optic nerve

the neural tube guves rise to the

CNS (central nervous systen)

telencephalon becomes the

cerebral hemispheres, olfactory bulbs, basal telencephalon

diencephalon becomes the

thalamus and hypothalamus

what cell death is responsible for parkinsons disease

substantia nigra

the rostral hindbrain becomes the

cerebellum and pons

the caudal hindbrain becomes the

medulla

mesencephalon becomes the

tectum and tegmentum

only mammals have a true

neocortex