__Tucked in the back of Brocaâs area is the Pars triangularis, which is implicated in the semantics of language. When you stop to think about something someoneâs saidâa line in a poem, a jargon-heavy sentenceâthis is the part of your brain doing the heavy work.
Know the causes. Brain atrophy is shrinking of the brain caused by the loss of its cells, called neurons. Two types of brain atrophy can occur; generalized and focal. Generalized atrophy refers to neuron loss throughout the entire brain, and focal atrophy refers to neuron loss in a specific brain region.
Diseases that affect the lower motor neuron at any point cause myofiber atrophy. The motor neuron exerts a trophic influence on muscle. This influence is mediated by induced contractions and by chemical substances (trophic factors) released at the synapse, which influence protein synthesis in muscle. Myofibers that lose their innervation become angular and shrink. They lose 80% to 90% of their mass within a few months. At an extreme stage of atrophy, virtually all sarcoplasm is lost and the myofiber is reduced to a cluster of nuclei.