Is it just the way nervous tissue reacts to death and degeneration? When the brain is deprived of glucose/oxygen it makes the animal go into tonic then clonic siezures. Is epilepsy a prinzmetal angina of the brain?
Reinforced neural circuitry which can involve vision, hearing, smell, taste and touch. When a path is used more than once the neurons and glia adjust themselves and next time when the impulse arrives it flows easily through the learnt path. So repetition is a good way of imrpoving memory and it can be reinforced by other pathways. In fact one sense can revive another circuit and so when we smell a favourite food we get memories of past events. Memory and dreams are similar. Dreams are usually in monochrome and almost always involve vision. Hearing, occasionally and smell, taste, touch almost never. Though the brain is in a standby mode during sleep, it is receptive to input. When a subject is dreaming if input goes in through touch/smell the info is incorporated; vision, hearing and taste are not possible without waking the subject.
Addiction and the amygdala (pleasure point)
Addiction is a reinforced neural pathway involving the amygdala. All addictive behaviour such as alcoholism, drug use, gambling, serial killer, rapist, liar, arsonist can be explained by this theory. Frontal siganls predominate on initial exposure and hesitancy, refusal may occur. Once the frontal inhibition is crossed a neural path is set and that involves the amygdala. Next time the behaviour is reinforced by the amygdala and repetition assigns it to memory. The frontal signal is therefore suppressed and pure amygdala signals take over. That explians the loss of personality in addiction and tendency to ignore responsibilities and complete focus on achieving the stimulation. All other frontal activities are ignored and even basic survival impulse is ignored due to the strong amygdala response. It is a vicious cycle and the more it is done the more it reinforces itself. Now the treatment can target enhancing frontal and other signals or suppressing the amygdala using targetted magnetic suppression/ablation. What other purpose does the amygdala serve? Can it be completely removed in addcits? The result will be a person with no pleasure!