Neurodegenerative disorders involve the progressive loss of nervous system function, usually because neurons die. The symptoms depend on which regions are affected. This lesson focuses on Alzheimer’s disease and Parkinson’s disease, two disorders with distinct effects on memory and movement.
Neurodegenerative disorders are illnesses characterized by a loss of nervous system functioning, usually caused by neuronal death. Because neuronal loss often continues over time, symptoms generally worsen. The location of the affected neurons helps determine the symptoms. For example, damage to neurons in the cerebellum can disrupt balance and walking.
All flashcards
What is a neurodegenerative disorder?
An illness involving loss of nervous system function, usually because neurons die. Symptoms often worsen as neuronal loss progresses.
What brain changes are commonly associated with Alzheimer’s disease?
Amyloid plaques, neurofibrillary tangles, and reduced brain volume are commonly observed. Neuronal loss in the hippocampus can be severe in advanced disease.
What is the significance of the APOE E4 variant?
It is a genetic variant associated with increased likelihood of Alzheimer’s disease. It is a risk factor, not a guarantee that someone will develop the disease.
What causes the characteristic movement problems in Parkinson’s disease?
Loss of dopamine-producing neurons in the substantia nigra disrupts a system that helps regulate movement.
How can L-DOPA ease Parkinson’s symptoms?
Brain neurons convert L-DOPA into dopamine, increasing dopamine neurotransmission and helping compensate for the loss of dopaminergic neurons.
Quiz questions
What does an electroencephalogram (EEG) record?Answer: Electrical activity of the brain using scalp electrodes.
Which feature defines epilepsy?Answer: Recurrent seizures.
Why must clinicians determine the type of stroke before choosing treatment?Answer: A clot-dissolving drug is not appropriate for a stroke caused by a burst vessel.
How do antipsychotic medications commonly reduce symptoms of schizophrenia?Answer: They block dopamine receptors and reduce dopamine neurotransmission.
What does the classic monoamine hypothesis propose about major depression?Answer: Reduced norepinephrine and serotonin neurotransmission may contribute to it.
Based on Biology 2e by Mary Ann Clark, Matthew Douglas, Jung Choi (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.