Question

What is the correct statement about the neuropathology of neurodegenerative diseases? a. Neuropathologic changes in neurodegenerative diseases are always detectable in at least one region of the nervous system. b. Residual neurons look sick or normal. c. In addition to the loss of neurons, there is always some gliosis and protein aggregates. d. If different regions of the brain are affected, the type of neurons degenerating remains identical. e. The multisystemic nature of a neurodegenerative process is explained by a trans-synaptic phenomenon.

Short answer

a. Neuropathologic changes are always detectable in at least one region of the nervous system b. Residual neurons can appear sick or normal. c. Neuronal loss, gliosis, and protein aggregates are always observed in all neurodegenerative diseases. d. The type of neurons degenerating remains identical if different regions of the brain are affected. e. The multisystemic nature of neurodegenerative processes is solely explained by trans-synaptic phenomena. Answer: b. Residual neurons can appear sick or normal.

Step-by-step solution

Analyzing option a

Neuropathologic changes in neurodegenerative diseases are often detectable in at least one region of the nervous system. However, this statement can't be confirmed as "always" detectable, as there might be undetectable changes or at early stages.

Analyzing option b

Residual neurons in neurodegenerative diseases may appear sick (exhibiting signs of damage or distress), or they may appear normal (with no apparent signs of damage). Therefore, this statement is accurate.

Analyzing option c

In neurodegenerative diseases, there is typically neuronal loss accompanied by gliosis (reactive response of glial cells) and protein aggregates (abnormal clumps of protein). However, this is not true in all cases, as some neurodegenerative diseases may not present all these features. Hence, this statement is not completely accurate.

Analyzing option d

In neurodegenerative diseases, if different regions of the brain are affected, the type of neurons degenerating might not remain identical. Different types of neurons may be affected in different ways, causing different symptoms and pathological characteristics. This statement is not accurate.

Analyzing option e

The multisystemic nature of a neurodegenerative process can be partially explained by trans-synaptic phenomena. These are disruptions in neuronal communication because of the degeneration of synapses. While this statement is somewhat accurate, it is not the sole explanation for the multisystemic nature of neurodegenerative processes.

Identifying the correct statement

After analyzing all options carefully, it is evident that option b (Residual neurons look sick or normal) is the most accurate statement about the neuropathology of neurodegenerative diseases.