ADHD is a neurodevelopmental disorder, not a cognitive disorder.

Alzheimer's disease is the most common type of cognitive disorder, accounting for 60-80% of cases.

Alzheimer's disease is characterized by the accumulation of amyloid plaques and tau tangles in the brain.

Parkinson's disease is characterized by the degeneration of dopaminergic neurons in the substantia nigra.

Hallucinations are the most common symptom of schizophrenia.

Dopamine is implicated in the pathophysiology of schizophrenia, with hyperactivity of the mesolimbic dopamine pathway thought to contribute to positive symptoms.

Huntington's disease is caused by a CAG trinucleotide repeat expansion in the HTT gene.

Huntington's disease is characterized by the degeneration of neurons in the striatum.

Behavioral changes, such as disinhibition and apathy, are the primary symptoms of frontotemporal dementia.

Frontotemporal dementia is characterized by the degeneration of neurons in the frontal cortex.

Creutzfeldt-Jakob disease is caused by the misfolding of the prion protein.

Creutzfeldt-Jakob disease is characterized by the degeneration of neurons in the cerebral cortex.

Muscle weakness is the primary symptom of multiple sclerosis.

Multiple sclerosis is characterized by the demyelination of neurons in the white matter.

ALS is caused by the degeneration of motor neurons in the brain and spinal cord.