im assuming by “types of folds” you’re referring to the gyri and sulci
(in simple terms, a gyrus (gyri plural) would be the outward-appearing lumps/bumps, and a sulcus (sulci plural) would be the deeper grooves inward)
despite the brain being split in two hemispheres down the middle by the longitudinal fissure, hemispheres are only symmetrical to an extent. structural asymmetry varies between individuals, brain regions, etc. so the short answer to your question is no
however, it of course follows the same structure on both sides. the superior frontal gyrus is gonna be in approximately the same spot on either side, the uncus gyrus in approximately the same spot, the pre&post central gyri in approximately the same spot on either side of the central sulcus.
then, there can be differences in an individual due to disorders like pachygyria or microgyria (abnormally large or small gyri, respectively) which can span the entire cerebral cortex or be localized.
if some functions are processed more in one hemisphere than another, that would impact symmetry. interestingly, some studies have shown that a LACK of left hemisphere asymmetry is observed in individuals with dyslexia. some research also found that the asymmetry between hemispheres is not due to genetics, so its believed to be due to experiences
another factor that can affect the symmetry/asymmetry between hemispheres is if a portion of the brain that is typically for “xyz” function is also working for “abc” function. if a region has greater between-subject variability, its more likely to be asymmetrical to its respective location in the other hemisphere.
skatergirl69420 t1_j8x9nhc wrote
Reply to Are the two sides of the brain symmetrical in shape/folds ? by freezeframepls
im assuming by “types of folds” you’re referring to the gyri and sulci (in simple terms, a gyrus (gyri plural) would be the outward-appearing lumps/bumps, and a sulcus (sulci plural) would be the deeper grooves inward)
despite the brain being split in two hemispheres down the middle by the longitudinal fissure, hemispheres are only symmetrical to an extent. structural asymmetry varies between individuals, brain regions, etc. so the short answer to your question is no
however, it of course follows the same structure on both sides. the superior frontal gyrus is gonna be in approximately the same spot on either side, the uncus gyrus in approximately the same spot, the pre&post central gyri in approximately the same spot on either side of the central sulcus.
then, there can be differences in an individual due to disorders like pachygyria or microgyria (abnormally large or small gyri, respectively) which can span the entire cerebral cortex or be localized.
if some functions are processed more in one hemisphere than another, that would impact symmetry. interestingly, some studies have shown that a LACK of left hemisphere asymmetry is observed in individuals with dyslexia. some research also found that the asymmetry between hemispheres is not due to genetics, so its believed to be due to experiences
another factor that can affect the symmetry/asymmetry between hemispheres is if a portion of the brain that is typically for “xyz” function is also working for “abc” function. if a region has greater between-subject variability, its more likely to be asymmetrical to its respective location in the other hemisphere.
heres an article if u care to read more:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4947520/