nevrodegenerative

Neurodegenerative conditions are disorders characterized by progressive loss of neurons in specific regions of the brain and nervous system, leading to decline in motor, cognitive, and autonomic functions. The underlying processes often involve abnormal protein folding and accumulation, synaptic dysfunction, and neuroinflammation.

Common neurodegenerative diseases include Alzheimer's disease (memory loss and cognitive decline), Parkinson's disease (bradykinesia, tremor, rigidity), amyotrophic lateral sclerosis (muscle weakness and atrophy), and Huntington's disease (chorea and cognitive changes), along with frontotemporal dementia, prion diseases, and other synucleinopathies. Each condition features characteristic protein abnormalities: beta-amyloid and tau in Alzheimer's; alpha-synuclein in Parkinson's; TDP-43 in ALS; and mutant huntingtin in Huntington's.

Causes are largely multifactorial and age-related. Familial forms arise from gene mutations (for example APP, PSEN1/2, or APOE4 risk in Alzheimer's; LRRK2 or GBA in Parkinson's). Environmental factors and gene–environment interactions also contribute, with a long preclinical phase before symptoms emerge.

Diagnosis combines clinical assessment with biomarkers and imaging. MRI may reveal region-specific atrophy; PET imaging can detect abnormal protein aggregates. Cerebrospinal fluid or blood biomarkers, along with neuropsychological testing, support differential diagnosis and disease staging.

There is no cure for most neurodegenerative diseases. Treatments focus on managing symptoms and preserving function; some disease-modifying therapies exist for select conditions, and research explores approaches targeting protein misfolding, inflammation, and neuronal resilience. Care is multidisciplinary, and prognosis varies by disease and stage.