|MadSci Network: Medicine|
Sex and death, a classical from psychiatry. Let's have a rather technical standpoint, and try to provide an answer to your questions.
According to physiology, sperm has two main compounds. A fluid, wich is produced by several glands, mainly the prostatic gland, and released during ejaculation. This fluid acts as a carrier. And cells, the spermatozoids. These cells are, in brief, produced by the testis on a continuous process, and stored between two ejaculations.
So it is technically possible to harvest not sperm but seminal fluid (a lower volume) from a man who is in "brain death" state, i.e. brain is dead but heart still beating. I imagine that such a scenario would take place in the situation of a young man, who sustained severe head injury, was declared brain-dead, and whose wife would ask for a sample of spermatozoids in order to begin a "post mortem" pregnancy. I dont know wether federal or state laws in the USA allow such a process. In France, this woould not be permitted.
It was classically admitted that, when a man was sentenced to death and hanged, he sometimes experienced erection and ejaculation. This phenomenon is explained by the interruption of descending controls through the spinal cord. Erection is an important symptom of acute medullar (spinal cord) trauma.
Ejaculation can be initiated by stress. Fighter pilots, after having escaped to very dangerous situtations, sometimes report that they ejaculated during escape manoeuvers. This is explained by very high levels of epinephrine, the hormone released by stress.
Regarding your last question, I believe it is a question of timing. Ejaculation is a reflex, so if this reflex is initiated and death occurs within seconds, the man will ejaculate while passing away. Needs a very good timing..........
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