Singh 6: The Forebrain Flashcards
What are the following structures associated with?
Limbic system
Thalamus
Basal Ganglia
Hypothalamus
Limbic system: emotion (amygdala)
Thalamus: relay center of the brain
Basal gangli: motor control
Hypothalamus: maintenence of the status quo
The central sulcus seperates the ____ from the ___
The central sulcus seperates the frontal lobe from the parietal lobe
Explain the following terms:
Commisures
Association fibers
Projection Fibers
Commisures connect left and right hemispheres (biggest example is the white matter band called the corpus collosum)
Association fibers: within one hemisphere
Projection fibers: cortex to caudal
Where are broca’s are and wernicke’s area located?
MOSTLY on the left hemisphere
for right handed people
it is not bilatteral, only on one side
Explain the areas involved in the following when you read outloud:
Perception of visual info
Integration of visual info
Comprehending visual info (i.e. words)
Speaking the words
Perception of visual info: visual input–> primary visual cortex
Integration of visual info: visual cortex–> visual association cortex
Comprehending the visual info: visual association –> Wernicke’s area
Speaking the words:
Wernicke’s area–> Broca’s area
Explain the dorsal stream vs the ventral stream in terms of vision?
“where” vs “what”
Dorsal: occipitalparietal “where information”… aka you can say the apple is in your hand
Ventral: occipitaltemporal, the “what”, aka you can identify the object as an apple
remember : Where is the door
and Vwhat is that
The basal ganglia is related to what?
What are the divisions of the basal ganglia?
Basal ganglia is related to motor control and motivated actions
Striatum: nucleus accumbens (reward center) and caudate
Lentiform: putamen, globus pallidus
Explain in general terms what the thalamus does
The thalamus is the relay center of the brain
It processes sensory info and relays it to the cerebral cortex
Explain the two important parts of the thalamus
Medial geniculate nuclei : associated with hearing
Lateral geneiculate nuclei: associated with vision
Thalamus:
The medial geniculate nucleus receives info from the _______, via the _________ (part of midbrain), and projects it to the _______
Thalamus:
Medial geniculate nucleus receives info from the cochlea, via the inferior colliculus, and projects it to the auditory cortex
Thalamus:
The lateral geniculate nucleus receives into from the ______ via the _______, and projects it to the ____
Thalamus:
Lateral geniculate nucleus receives into from the retina via the superior colliculus and projects it to the occipital lobe
The Hypothalamus Integrates:
1.
2.
3.
Explain
The hypothalamus integrates: endocrine function, autonomic function, and motivated behaviors
Homeostasis: fluid balance, temp regulation, stress response, cicadian rhythm, sleep and arousal
Motivated behaviors: sleep, feeding, reproduction, sickness
Coronal view of hypothalamus:
Perventricular area important for?
What structure seperates the medial and lateral hypothalamus?
Periventricular area: neuroendocrine function
Medial: site of limbic input
Lateral: relay station, hunger center
What seperates the medial and lateral hypothalamus is called the fornix
Ventromedial part of hypothalamus is the _____ center
Getting a lesion in the middle part of your hypothalamus would cause what?
Middle part of the hypothalamus is the SATIETY center
Lesion would cause uncontrolled eating
Anterior hypothalamus is in control of what kind of regulation?
Anterior hypothalamus: thermoregulation
menopause: hot flash
Explain the HOME pneumonic with the limbic system
Functions of the limbic system
Homeostasis
Olfaction
Memory
Emotion
How does the limbic system effect emotion?
Three effector systems for the behavioral expression of emotion:
1.
2.
3
Somatic motor system: behavioral expression of emotion (aka smiling)
Endocrine system
Autonomic System
Explain the papez circuit
Essentially
when we get all riled up and scared the amygdala triggers the hypothalamus—> thalamus—> neocortex
the neocortex can calm you down depending what is going on
also the hippocampus and memory can triger these things
What does the amygdala do?
What is it assocaited with?
The amygdala relates enviornmental stimuli to coordinated behavioral, autonomic, and endocrine responses seen in self preservation
Associated with:
gut reactions
Fear conditioning
Forms associative memories
Social/facial recognition
PTSD
The cortex is important for what?
What does Phineas Gage have to do with the cortex?
Cortex keeps inappropriate behaviors in check
Phinneas Gage had a lesion in his ventromedial/prefrontal cortex
Where is the amygdala and limbic system located?
What is near it?
amygdala: medial TEMPORAL lobe
Hippocampus is also in the temporal lobe
temporal lobe also has wernicke’s and broca’s areas as well
therefore, pt having strange smells, weird emotional response, fear—- temporal lobe seizure
Explain which sections of the forebrain are bathed by each artery
Anterior cerebral
Posterior cerebral
Middle cerebral
Anterior cerebral: frontal cortex, lower extremity motor function
Posterior cerebral: occipital lobe
Middle cerebral: upper extremity motor issues, SPEECH problems (temporal lobe)
