The document discusses different types of nervous system disorders including aphasia, dysphasia, hyperalgesia, and analgesia. Aphasia is a speech disorder caused by brain damage that makes it difficult to communicate through language. Dysphasia is also a speech disorder characterized by impaired speech production and arranging words. Hyperalgesia is an increased sensitivity to pain caused by damage to pain receptors or nerves, while analgesia is the absence of pain without loss of consciousness, often produced through analgesics or pain medicines.