Functional Anatomy of the Central Nervous System Flashcards
why is it important to study neuroanatomy?
its important to understand brain functions and disorders by knowing where its coming from
essential to know for diagnosis and treatment of disorders
what are the 6 subdivisions of CNS?
- cerebrum
- diencephalon (hypothalamus and thalamus)
- midbrain (basal ganglia, hippocampus/limbic system)
- pons and cerebellum
- medulla
- spinal cord
What is the postcentral gyrus and pre-central gyrus?
post central gyrus is located more towards the parietal lobe and it is the primary sensory cortex
precentral gyrus is located more towards the frontal lobe and is the primary motor cortex
What is the basic functions of the frontal, parietal, occipital and temporal lobes?
frontal: short term/working memory, planning behaviors
parietal: processing somatosensory information and spatial cognition
occipital lobe: visual processing/v1
temporal lobe: on the surface is the auditory cortex (temporal gyrus) and subcortical areas include memory function like hippocampus and amygdala
What is critical to be present in order to improve cortical functions and plasticity across multiple brain regions?
an enriched environment
What are the major functions of the prefrontal cortex?
- 1/3 of human neocortex
- temporal organization of behavior (when behavior should occur)
- lesioning to this area causes impaired initiation, and performance of goal directed behavior and bad STM retention
- lesions do not affect ur normal motor routines, iq or memory
What was the main thing to come out of phineas gage’s case study?
played a major role in developing our understanding of the localization of brain functions
What are 2 pathways for visual processing and what do they do?
- dorsal stream (vision for action)–> goes from striate cortex (v1) to extrastriate cortex and then to posterior parietal cortex
- ventral stream (vision for perception) –> goes from striate cortex, to extrastriate cortex and to inferior temporal lobe
What happens when a person’s dorsal stream is damaged?
they develop optic ataxia: a disorder involved in the inability to convert what we see in a moving action
their grasping is defective (they cant form fingers to shape the object they’re grasping) but manual estimation of the size of the object using their fingers is normal
What happens when a person’s ventral stream is damaged?
damage to inferior temporal lobe causes visual form agnosia which is impaired recognition of objects
slot task used to test visual form agnosia (seeing objects but not being able to identify them)
- they do very poorly on matching the cassett with the slot but do normal on imagining to match a cassett into the slot
they also do better when drawing something from memory compared to drawing it from a copy of a model bc theres no visual input involved
What is hemineglect?
unilateral damage to the parietal lobe
- patient ignores half of vision
usually a damage to the right parietal lobe leads to neglect of left visual field
What are the two main areas in the temporal lobes? What are their functions?
- hippocampus (involved in learning and remembering facts and events)
- Amygdala (involved in emotional expression and forming proper associations between events and emotions)
- they share alot of fibers with each other and are good at forming associations especially for human learning
What is Amnesia? What are 2 types of amnesia?
amnesia is memory loss from concussion, tumours, lesions or diseases
- retrograde amnesia: loss of memory prior to the time of trauma only (i.e. maybe a few years before the trauma) but retained childhood memory and any new formed memory is good
- anterograde amnesia: loss of memory after trauma and inability to form new memory (common in alzheimers)
What area of the brain is critical for memory consolidation?
the hippocampus is thought to be centre where STM gets converted to LTM via consolidation
STM has a limit of 6/7 items we can remember but LTM has no such limit at all
Memory that enters STM and is not consolidated is lost
What occured to H.M? what kind of memory loss did it result in and what was noted about it?
h. m had his medial temporal lobes removed
- he developed anterograde amnesia (inability to form new memory)
- he had an intact STM and procedural/implicit memory (memory of unconscious stuff)
- this told researchers that brain structures that underlie concious and unconscious memory (explicit/implicit) memory are distinct
