Some comments on deja vu by Wilder Penfield.
Penfield's expansion of the interpretive cortex includes the phenomena of déjà vu. Déjà vu is defined as the sensation that an experience an individual is presently experiencing has previously been experienced. Déjà vu is typically experienced by individuals between the ages of 15 to 25, and only affects approximately 60-70% of individuals. It is thought to be a mismatch of the sensory input individuals receive and the system in which the brain recalls memory. Another thought on the cause of déjà vu is that there is a malfunction in the brain's short- and long-term memory systems where memories become stored in incorrect systems. There are a couple of ways one can recognize familiar experiences - by mentally retrieving memories of a previous experience, or by having a feeling that an experience has occurred when it actually has not. Déjà vu is having that feeling of familiarity in a situation that is completely new. Memory is good at being familiar with objects, however it does not do well with the configuration or organization of objects. Déjà vu is an extreme reaction to the mind telling an individual that they are having a familiar experience. Déjà vu is thought to be a consistent phenomenon. However, it has been associated with multiple psychiatric disorders such as epilepsy, schizophrenia, and anxiety, but there has not been a clear, frequent diagnostic correlation between déjà vu and psychiatric disorders, except with patients that have a possibility of being epileptic. Temporal lobe epilepsy affects the hippocampus. Patients that suffer from this medical diagnosis are said to have a misfiring of the brain's neurons. The neurons transmit at random which results in the false sense of experiencing a familiar situation that had previously been experienced. Different types of déjà vu are difficult to pin point because researchers who have studied déjà vu have developed their own categories and differentiations. On a broad perspective of research that is available, déjà vu can be divided into two categories - associative déjà vu and biological déjà vu. Associative déjà vu is typically experienced by normal, healthy individuals who experience things with the senses that can be associated to other experiences or past events. Biological déjà vu occurs in individuals who suffer from temporal lobe epilepsy. Their experience of déjà vu occurs usually just before they experience a seizure. Recent research is looking at the new occurrence of chronic déjà vu. Chronic déjà vu is when an individual is experiencing a constant state of déjà vu. Failure of the temporal lobe is thought to be the cause of this phenomenon because the circuits that connect to memories get stuck in an active state, and create memories that never happened.
Or, as Yogi Berra said: "It's like deja vu all over again."
This would seem to place the argument in the individual brain rather than in alternate universes. Although there probably are billions of the suckers, it may be that they are closed systems, beyond reach ... although I prefer to think that isn't true.
Humanity has arrived where it is through risky speculations and actions; and to dismiss out of hand any theory, however weird, concerning the universe and the human brain is really quite silly. Off-the-wall ideas such as sub-atomic particles, a heliocentric universe, even that the earth was not flat, were once dismissed as "a load of balls"
If everyone thought like that men would still be painting their balls blue and dragging women off into caves. Come to think of it, if it were consensual, that wouldn't be a bad idea.