pathological mental process thought blocking When the person begins speaking again, after the block, they will often speak about a subject unrelated to what was being discussed when blocking occurred. It is described as being experienced as an unanticipated, quick and total emptying of the mind. People with schizophrenia commonly experience thought blocking and may comprehend the experience in peculiar ways. http://en.wikipedia.org/wiki/Thought_blocking Phenomenon that occurs occurs when a person's speech is suddenly interrupted by silences that may last a few seconds to a minute or longer.