Final answer:
The yellow-brown pigment that accumulates in neurons and may be a sign of cellular stress is lipofuscin.
Step-by-step explanation:
The yellow-brown pigment that accumulates in neurons and may be a sign of cellular stress is lipofuscin. Lipofuscin is a type of age pigment that builds up in cells as a result of cellular damage, oxidative stress, and the aging process. It is often seen in neurons of older individuals and is thought to be a marker of cellular aging and dysfunction.
For example, in Huntington's disease, neurons may accumulate lipofuscin as a result of the abnormal huntingtin protein and the neurodegenerative process.
Overall, lipofuscin accumulation in neurons can be a sign of cellular stress and age-related damage.