anatomy 403: neuro 5: diencephalon, cerebral cortex, and limbic system

what are the regions of the diencephalon?

epithalamus, thalamus, hypothalamus, ventral thalamus

what structure is in orange?

epithalamus (pineal gland and habenula)

what structure is in red?

hypothalamus

what structure is in pink?

thalamus

dorsal thalamus

• usually referred to as the thalamus

• all sensory information passes through the thalamus prior to cortex with one exception of _______

olfaction

dorsal thalamus

• largest part of the diencephalon

• midline structure

• 2 hemispheres: connected by the ________

• connections: motor, sensory, and limbic cortex, reticulating activating systems of the brain stem

massa intermedia

sensory thalamus

• _______

  • afferent: inferior colliculus

  • efferent: auditory radiations

medial geniculate

sensory thalamus

• ________

  • afferent: optic tract 

  • efferent: optic radiations aka geniculocalcarine tract

lateral geniculate 

sensory thalamus

• what is the A1 portion of the brain?

primary auditory cortex

sensory thalamus

• what is the V1 portion of the brain?

primary visual cortex

sensory thalamus

• ventral posterior

  • afferent systems: ________, _______

  • efferent systems: somatosensory cortex via the internal capsule and S1 (primary sensory cortex)

medial lemniscus, anterolateral system

sensory thalamus

• what does the medial lemniscus sense?

fine touch and proprioception

sensory thalamus

• what does the anterolateral system sense?

temperature, gross touch, pain

motor thalamus

• ventral anterior and ventral lateral

• part of the ______

  • receives info from basal nuclei (ganglia) and reports back to motor cortex

basal nuclei loop 

hypothalamus

• sends and receives hormonal and other molecular signals via the vascular system, as well as neural signals

• main functions:

  • control of the ________

  • control of the autonomic nervous system and variety of survival behaviors

pituitary gland

hypothalamus

• control of the pituitary gland

• the ______ and ______ nuclei contain neurons that produce oxytocin and vasopressin that release these peptides onto the capillaries of the posterior pituitary

paraventricular, supraoptic 

hypothalamus

• control of the pituitary gland

• the hypothalamus control the _____ by secreting releasing factors into the _______portal system

• unlike many other endocrine tissues, the anterior pituitary is so dependent on the hypothalamus, that it is not transplantable 

anterior pituitary, hypophyseal

hypothalamus - circadian rhythms

• what is the process?

retina → suprachiasmatic nucleis → paraventricular nucleus → intermediolateral cell column → superior cervical ganglia → pineal gland → melatonin secretion 

hypothalamus - thermoregulation

• __________

  • heat conservation, shivering, construction of blood vessels

  • destructions reults in hypothermia

  • sympathetic nervous system

posterior nucleus (dorsal hypothalamis area)

hypothalamus - thermoregulation

• __________

  • heat dissipation, sweating, dilation of blood vessels near the body surface

  • destruction results in hyperthermia

  • parasympathetic nervous system

anterior nucleus (median preoptic area)

cerebral cortex

• in human, the vast majority of the cortical hemisphere occupied by _______

  • unique to mammals

• gray matter = neurons arranged in layers

• white matter = myelinated fiber tracts

neocortex

cerebral cortex

• what matter are neurons found arranged in layers?

gray matter

cerebral cortex

• what matter are myelinated fibers tracts?

white matter

cerebral cortex

• basic 6-layered organization is conserved across all mammals

  • ______ (new, 6 layers_

  • ______ (middle 4/5 layers)

  • ______ (other) cortical areas

neocortex, mesocortex, allocortex

cerebral cortex

• layer 4 is the ______ zone of thalamocortical axons

recicpient

cerebral cortex

• layers 3, 5, and 6 are the ____ layers, sending axons to other cortical or subcortical targets

output

cerebral cortex

• I: molecular

• II: external granular

• III: external pyramidal

• IV: internal granular

• V: internal pyramidal

• VI: fusiform

just put ok

ok

cerebral cortex

• what is layer 1 called?

molecular

cerebral cortex

• what is layer 2 called?

external granular

cerebral cortex

• what is layer 3 called?

external pyramidal

cerebral cortex

• what is layer 4 called?

internal granular

cerebral cortex

• what is layer 5 called?

internal pyramidal

cerebral cortex

• what is layer 6 called?

muliform (fusiform)

cerebral cortex

• what makes up layer 1?

apical dendrites of pyramidal neurons

cerebral cortex

• what makes up layer 2?

recipient zone of diffuse thalamic projections and other subcortical nuclei (basal forebrain, brain stem, and hypothalamus)

cerebral cortex

• what makes up layer 3?

cortico-cortical projections

cerebral cortex

• what makes up layer 4?

recipient zone of precise, topographically organized projections from specific thalamic nuclei

cerebral cortex

• what makes up layer 5?

is the principal output layer to the subcortical (bigger)

cerebral cortex

• what makes up layer 6?

output to thalamus

cerebral cortex

• primary ______ areas: M1, S1, A1, V1

motor and sensory

white matter

• what are the three types of connections within the brain?

commissural, projection, association

white matter

• projection fibers project out of cortex to subcortical targets in the ______

  • connections between the brain and lower centers

internal capsule

white matter

• commissural fibers span both cerebral hemispheres in the _________

  • interhemispheric

corpus callosum

white matter

• association fibers are on the same side of the hemispheres

  • arcuate fasciculus and _____

  • intrahemispheric

cingulum

limbic system

• function: regulation of emotional behavior (anger, rage, sexual activity)

• pathways to and from the hypothalamus and limbic system ____ each other

parallel

limbic system

• the ________ receives information about the prefrontal association cortex, the amygdaa, and ventral tegmental area

  • sends informationn to the globus pallidus and substantia nigra

  • it is thought to be our _____ system and associated with addiction and pleasure

nucleus accumbens, reward

limbic system

• hippocampal formation and amygdala

  • often described as being “inside” the _______

  • hippocampal formation may be viewed in the floor of the inferior horn of the lateral ventricle 

telecephalon

limbic system

• what structure is this?

amygdala

limbic system

• what structure is this?

hippocampal formation 

limbic system

• the amygdaloid complex contains multiple nuclei

  • lcoated in the _____ lobe, rostral of the hippocampal formation, at the anterior end of the temporal horn of the lateral ventricle

  • function: general limbic emotions and behaviors, fear, anger, satiety, and environmental contexts

  • stimulation: fear, rage

  • _____: highly variable responses, passivity, and hypersexuality 

temporal, ablation

limbic system

• what are the three parts of the hippocampal formation?

dentate gyrus, hippocampus, and subiculum

limbic system

• dentate gyrus layers from superficial to deep?

molecular, granular, polymorphic

limbic system

• hippocampus layers from superficial to deep?

polymorphic, pyramidal, and molecular

limbic system

• what structure is this?

subiculum

limbic system

• what structure is this?

dentate gyrus

limbic system

• what structure is this?

hippocampus (CA1, CA2, CA3)