Video Module 2: Neuroanatomy Flashcards
how many cells does the brain have?
- approximately 100 billion nerve cells
- approximately one trillion glial cells
do we really only use 10% of our brain?
- No: this is a myth
- Only 10% of the cells in our brain participate in communication; the rest of the cells in our brain take-on supporting duties
primary functions of the brain
1) creating a sensory reality by gathering info from the environment and body
2) integrating information by sending it to the brain to make sense of it; making decisions based on the information
3) producing motor output based on the information input; includes speaking, pointing, walking, writing, etc.
central nervous system
- brain and spinal cord
- brain is the central processor: where cognition takes place; where the integration of neural signals takes place
peripheral nervous system
- nerves everywhere except the brain and spinal cord
- carries information to and from the brain
- autonomic nervous system
- somatic nervous system
autonomic nervous system
- part of the PNS
- controls unconscious functions such as breathing and digestion
- communicates with internal organs and glands
- sympathetic ANS: arousing (shuts down digestion, increases heart rate)
- parasympathetic ANS: calming (slows heart rate, decreases pupil size, resumes digestion)
somatic nervous system
- part of the PNS
- communicates with sense organs and voluntary muscles
- sensory (afferent) SNS: handles sensory input; brings info in
- motor (efferent) SNS: handles motor output; brings info out to create movements
cortical lobes
- separated by major fissures:
1) longitudinal: separates hemispheres
2) central: separates frontal and parietal lobes
3) lateral: separates frontal+parietal lobes from the temporal lobe - consists of the frontal, parietal, temporal, and occipital lobes
frontal lobes
handles motor and executive functions
parietal lobes
handles somatosensory information and information of spatial locations
temporal lobes
handles audition (hearing), speech, and emotion
occipital lobes
handles vision; early visual processing
subcortical structures
- basal ganglia: located around the thalamus; controls movement; “the reptilian brain”
- limbic system: hypothalamus; thalamus; olfactory bulb; amygdala; hippocampus; “the mammalian brain”
thalamus
- part of the limbic system
- located on top of the spinal cord
- responsible for relaying sensory information to other parts of the brain
- does not process olfactory information/smell (that goes to the olfactory bulb)
hypothalamus
- part of the limbic system
- located under the thalamus
- controls motivated behaviours: eating, drinking, sexual intercourse
- a point of contact between the nervous system and the endocrine system
amygdala
- part of the limbic system
- involved in regulating and processing emotion
hippocampus
- part of the limbic system
- crucial in memroy formation and consolidation
primary projection areas
- regions of the cortex where sensory input first arrives and where motor output last exists
- primary somatosensory projection area, primary motor projection area, primary visual cortex, primary auditory cortex
primary somatosensory projection area
- somatosensory cortex
- representation of the sensitivity of body parts is proportional to cortical area
primary motor projection area
- motor cortex
- representation of the motor control of body parts is proportional to cortical area
primary visual cortex
- projection map of our visual cortex
- locations in space correspond to cortical areas of the primary visual cortex
primary auditory cortex
- projection map of different pitches and tones
- different pitches and volumes correspond to cortical areas
association areas
- 75% of the cortex
- create associations between simple ideas and sensations
damage can result in:
- frontal lobe: apraxia
- occipital/temporal lobes: agnosia
- frontal and temporal lobes: aphasia
- (right) parietal lobe: neglect syndrome
superior
above
rostral
towards the front of the brain
dorsal
toward the top of the brain
ventral
toward the belly/underside of the brain
caudal
towards the back of the brain
inferior
below
anterior
in front of
posterior
behind
lateral
toward the edge of the brain (toward the cortex)
medial
toward the middle of the brain
contralateral organization
the idea that many of the brain’s circuits are crossed
- one hemisphere controls and integrates information from the opposite side of the body
- sensations from the R side of the body are projected onto the L hemisphere; sensations from the L side of the body are projected onto the R hemisphere
- R visual field –> L hemisphere
- L visual field –> R hemisphere
is the brain symmetrical or asymmetrical?
- the brain is both asymmetrical and symmetrical
- both hemispheres: emotion and vision; cortical lobes and many subcortical structures
- lateralized to the L: language
- lateralized to the R: spatial location information