Lecture 3 Flashcards
Brain - General Info
Divided into 2 hemispheres, right and left
Avg human brain weighs 3 lbs
88% water, 12% neurons, glial cells, and connective tissue
Corpus Callosum
Band of fibers that connects the two hemispheres of the brain
Descriptive divisions of the brain
Cerebrum
Diencephalon
Brain Stem
Cerebellum
Cerebrum
What you see from the outside of the brain
Convolutions
Ridges and valleys on the surface of the brain
Gyri/Gyrus
The ridges on the brain’s surface
Sulci/Sulcus
The valleys on the brain’s surface
Fissures
Deep sulcus
Superior Longitudinal Fissure/Interhemispheric Fissure
The deepest and longest of the fissures; runs between the two hemispheres
Lateral/Sylvian Fissure
The fissure on the lateral surface of the brain
Central/Rolandic Fissure
Superior to lateral fissure
Transverse Fissure
Separates the cerebellum from the cerebrum
Frontal Lobe (Location)
The lower boundary of the frontal lobe is the lateral fissure, the upper boundary of the frontal lobe is the central fissure.
Frontal Lobe (Structural Overview)
Primary Motor Cortex/Precentral Gyrus
Olfactory Tract & Olfactory Bulb
Broca’s Area
Primary Motor Cortex/Precentral Gyrus
A structure in the frontal lobe
Involved in the voluntary control of skilled movement of muscles that are contralateral
Injury to this area will cause paralysis to a place on the body contralateral to the site of injury
The body parts are disproportionally represented in the primary motor cortex (some parts of the body have a lot of the cortex devoted to them)
Homunculus
The disproportionate representation of body parts in the primary motor cortex
Olfactory Tract & Olfactory Bulb
Allows us to smell
Inferior side of the brain, two white lines with bulbs at the end, one in each hemisphere
Broca’s Area
Only on the left hemisphere
Responsible for speech production
Formed by 3 Structures:
Pars Triangularis
Pars Orbitalis
Pars Opercularis
Parietal Lobe (Overview)
Shares boundaries with all other lobes
Controls perception, visual spacial information, touch, and body awareness
Injury to this area causes Tactile Agnosia/Astereognosis and Visual Spacial Impairment
Parietal Lobe Structures
Postcentral Gyrus/Somatosensory Cortex
Angular Gyrus
Supramarginal Gyrus
Tactile Agnosia/Astereognosis
Caused by injury to the parietal lobe
A disorder in which the patient is unable to recognize objects by touch even though they have intact ability for tactile perception
Visual Spacial Impairment
Caused by injury to the parietal lobe
A disorder in which the patient is unable to copy geometrical figures, has difficulty discriminating complex visual stimuli
Postcentral Gyrus/Somatosensory Cortex
Processes sensory (somesthetic = skins, tendons, and joints) information contralaterally
Ex. Pain, temperature, touch, and pressure
Angular Gyrus & Supramarginal Gyrus
Structures important for language reception and object recognition; facilitate integration of information related to hearing, vision, and touch
Damage to these areas in the left hemisphere lead to issues in language reception and object recognition
Temporal Lobe (Structural Overview)
3 Primary Gyri we need to know:
Inferior Temporal Gyrus
Middle Temporal Gyrus
Superior Temporal Gyrus (Left Temporal Hemisphere)
Left Temporal Lobe
involved in verbal sound comprehension (written and spoken language)
Right Temporal Lobe
Right temporal lobe is involved in nonverbal language comprehension (Sounds and music)
Right temporal lobe also processes complex visual stimuli
Primary Gyri of the Temporal Lobe
Inferior Temporal Gyrus
Middle Temporal Gyrus
Superior Temporal Gyrus (Left Temporal Hemisphere)
the posterior portion of this is responsible for language comprehension
AKA Wernicke’s Area AKA Superior, posterior temporal gyrus
Heschl’s Gyrus or Transverse Temporal Gyrus or Primary auditory cortex
Responsible for audition/hearing
Receives input from each ear from both hemispheres
