the cerebrum

what is included within the cerebrum?

the frontal, parietal, occipital & temporal lobes

what is the fissure that separates the left and right hemispheres?

the longitudinal fissure

what is the innermost part of the cerebrum?

the insula

gyri vs sulcus

gyri is an elevated ridge & fold, sulcus is a groove; both of these increase the surface area of the brain & increases information processing

define gray matter

includes the soma, dendrites & unmyelinated axons

how is gray matter separated (superficial vs deep)?

the cortex is superficial while the nucleus is deep and is made up of a functional group of soma

define white matter

myelinated axons and tracts, which is where most of the volume of the brain comes from

define tracts

tracts are groups of axons that travel throughout white matter together

define the connections of white matter

projections: connection of the brain & spinal cord

commissural: connection of the left & right hemispheres via the corpus callosum

association: connection of individual regions WITHIN either the left or right hemispheres; these DO NOT cross the midline of the brain

define the different functions of the cerebrum

sensory function, motor function & association

define how the prefrontal cortex is the largest association cortex

it is involved in the majority of action within the cerebrum, including planning, decision making, behavioral regulation and self awareness, all of which are fully developed by ~25 years of age.

what does the precentral gyrus function in?

voluntary movement (is the primary motor cortex)

where is broca’s area located and define its function

located in the left frontal lobe, involved in speech production via motor coordination of muscles and grammatical structure

what is broca’s aphasia?

the inability to produce speech while leaving actual language comprehension unaffected. speech is reduced to single words or short phrases and can also impact writing and sign language.

what is the parietal lobe involved in?

spatial awareness & visual attention (parietal association cortex) , primary somatosensory cortex & general sensation (postcentral gyrus) , and integration of stimuli & tactile memory (somatosensory association cortex)

what is the temporal lobe involved in?

it is the primary auditory cortex and is where the olfactory cortex is located

what 2 cortex’s does the temporal lobe contain in addition to the primary auditory and olfactory cortex’s?

the auditory association cortex (where classification of sound happens) and the visual association cortex

describe wernicke’s area and what lobe it is found in.

it is found in the left temporal lobe of the cerebrum and is where speech comprehension occurs (words linked with symbolic meaning)

describe wernicke’s aphasia

this is when somebody has fluent but nonsensical speech; they can understand language but can’t construct a sentence properly. reading and writing is also usually severely impaired.

what occurs in the occipital lobe?

this is the primary visual cortex and contains the visual association cortex where color, orientation and shape of objects and things are registered

what is the insula?

it is where the vestibular, gustatory & visceral sensory cortex’s are located

what occurs within the basal nucleus of the cerebrum?

it is where voluntary movement is controlled. here voluntary movements are initiated as well as executed. this area inhibits antagonistic or unnecessary movements. the basal nucleus also integrates information from multiple brain regions which are important for muscle memory, habitual behaviors and decision making.

what parts of the cerebrum make up the limbic system and what are they involved in?

the cingulate gyrus, hippocampus, amygdala and corpus callosum. the limbic system is involved in emotional expression, memory formation and fear response.

how does the formation of memories occur?

memory formation occurs through the encoding, storage, and retrieval of information, within the hippocampus. types of memory storage include declarative and nondeclarative which are conscious and unconscious recollection and intermediate, short term and long term which are storage of memories for only moments, minutes and years respectively. short term memory is working memory and limited to only short sequences.

what is the consolidation of memory?

it is the slow transfer of short term memories into long term storage through association, rehearsal and emotion. the hippocampus organizes stimuli into unified groups of information through inducing long term potentiation, which involves increased synaptic activity between neurons and involves greater dendrite growth and neurotransmitter release. these memories are stored in related sensory regions, such as the visual cortex for visual memories and the auditory cortex for auditory memories.

what is spatial navigation?

this is where the hippocampus forms a cognitive map of the environment, allowing for the understanding of spatial relationships and aiding in the navigation of physical spaces. an example of this is maguire et al.2020 which is where there was found to be an increase in hippocampus gray matter in london taxi drivers as they were required to memorize all of london in order to drive.