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President of The New England Skeptical Society

Miranda y Skynet

Is it possible to dream about real things that happened or are happening in another place?

There is no "psychic" connection between our brains in the dream state and any external reality. Current conventional wisdom is that when we dream we are processing information we were recently exposed to. So it is possible that our dreams can be triggered by recent experiences, even those we are not fully consciously aware of. But there is no evidence that our dreaming brains can access information either remotes or in the past through "anomalous" means.

aLZiNouS

What importance has the Internet played as an instrument for diffusion of critical thought?

Invaluable. The internet is an incredible resource of information, and has been an effective way to distribute critical information. The most useful feature is that when someone is interested in or researching a particular topic, they can search the internet and find an otherwise obscure critical article. So information gets to the people who need it.

Of course, the same is true for the purveyors of nonsense as well. The internet has proven a useful tool for marketing snake oil and spreading pseudoscience.

Paradoja EPR y Moebius

Is it true that awareness is a kind of quantum state of the mind?

There is no evidence for this, and current models of brain function do not incorporate quantum effects. Quantum effects are very fragile and break down quickly above the atomic scale due to decoherence. (Incidentally, my current article, in press, is about this topic.)

Agnóstico

Like a good Italian-american, you surely would have been baptized a Catholic. In Europe the Catholic Church accepts Darwin's evolution of the species as science that does not obstruct the idea of a created universe. What happened in the U.S.A. so that from other Christian denominations have arisen regressive theories like Intelligent Design?

America was founded by puritans, and to this day there exists a strong puritan influence in this country. A large number of Christians belong to fundamentalist sects who teach a literal interpretation of the bible. Ever since Darwin there has been a simmering grass-roots anti-evolution movement in the US, tied to fundamentalist and evangelical Christian churches.

Manuel

How would you foment critical thought from childhood?

I have two daughters, aged 6 and 3, so I have been considering this question deeply. I think it is important to expose your children to science and knowledge, and to make it fun. Show them the joy of learning, of mastering a topic, and of thinking. When my older daughter asks a question, I will typically turn it back on her and ask her how we could know the answer, or how we could figure it out together. At every opportunity I try to get her to think on her own, rather than trust an authority. I let her know that there isn't a black and white answer to every question, and sometimes we don't know what the answer is. Yet, at the same time, I let her know that some answers are better than others - because they make more sense or because they are supported by more evidence. So she knows that belief in Bigfoot is "silly" and has some idea why.

Luz

What is the neurological explanation for DejaVu?

It's not know for sure, but the current theory is that it is an echo or replay of information in our hippocampus. The hippocampus is an important structure for memory and largely where our short-term working memory is held.

Claudio_Talca

I would like to know, according to you, what are the different techniques or methods used by gurus or teachers from different practices or cults to obtain such a big amount of followers? What cerebral areas are more vulnerable to these tricksters?

Typically, cult leader are charismatic and authoritarian. They lure people in with their charisma and by a host of psychological appeals, such as belonging to a community, feeling loved, being a member of an "elite" or chosen group, and having a divine purpose. The authoritarian structure breaks down free will and makes people more dependent upon the cult and its leader.

Cults vary is size from very few people to millions. This largely depends upon the charisma of the leader and how aggressively they try to spread and get new members.

Guillermo Cano y Astrosur

Sometimes I have a feeling about things, that later really happen. Not always, only on occasions. Why does this happen? Do you deny these premonitions?

These types of experiences are due to the combination of coincidence and subjective validation. Coincidences happen, far more often than you might think naively. Our days are filled with many events, thoughts, and people. Random correlations should happen on a regular basis, and occasionally very unusual correlations should occur, and rarely seemingly impossible coincidences should occur at random. But people have a very poor innate grasp of statistics, especially the statistics of large numbers - such as the number of events that make up our daily lives.

Subjective validation means that when a coincidence occurs, we notice and remember it, because it has some significant for us. When they do not occur, we do not notice the non-event. So our perception of how often coincidences occur is very skewed. This makes them seem more significant than they are.

There is another psychological mechanism at work, that of the open-ended criteria. This refers to the fact that there is no a-priori rule or criteria as to what constitutes a correlation. If you dream about someone you haven't seen in a while, then you later encounter them in some way, how much time can go by between your dream and the encounter in order for that to be considered a "premonition?" A day, a week, a month? Do you have to actually see them? Would a telephone call suffice. How about an e-mail, or just hearing from a mutual friend? With open-ended criteria the probability of a chance correlation is greatly enhanced.

Further, regarding plausibility, having a premonition about the future requires time travel, which is a physical impossibility (barring possible extremely exotic situations that are not present on the earth). Somehow information from the future would have to travel back in time to your brain. This would require a significant rewriting of the physics textbooks, and there is no credible evidence that anything like this can occur. Occam's razor strongly favors the conclusion that such experiences are just a little bit of coincidence and subjective validation.

mmarinm56

If, as some scientists maintain, there are other dimensions (i.e. string theory), in addition to those that we already know of, is it possible that we may be visited by beings from those other dimensions, that then are taken as ghosts, goblins, etc.?

The other dimensions that cosmologists talk about are not capable of supporting life or existence as we know it. Also, it is important to note that string theory and other such theories at this point are purely mathematical constructs without any empirical support. In fact, no one has thought of a way to even empirically test them.

However, it is theoretically possible (although highly speculative) that a phenomenon from another dimension adjacent to our universe (actually part of our universe but displaced into another dimension) could produce some bizarre anomaly in our 3-dimensional physical world. However, it is difficult to image how anything from another physical dimension could look like a vaporous human form.

At this point such explanations are too speculative and problematic to invoke as an explanation for any phenomenon. Also, there is no credible evidence that ghosts exist as a real phenomenon, outside of the minds of believers.

Tigris

What do you know about sonotherapy, the use of tuning forks, the frequency of Schuman etc.? Equally, are the therapies that use the frequency of colors useful to heal?

Therapies based upon sound or light frequency to heal are pure pseudosciences. There is no evidence to support their claims, practitioners have not done any real research, and there is no plausible scientific rationale for their claims.

There are many manifestations of these concepts - energy healing, shamanic healing, and earth resonance, zero point nonsense.

Mitschman y Liberto

Regarding the inexplicable healings, for which there does not exist a medical explanation, and that are considered miracles by the catholic church - is it possible that the human body, a product of voluntary or involuntary mental impulses, generate the changes or reactions necessary to produce the cure?

It depends on what specific case or disease you are talking about. All of the cases of so-called miraculous healing have one of the following features in common:

• The cured disease was one that is amenable to spontaneous remission, in other words it is known in some cases to resolve on its own.
• There was inadequate documentation that the disease existed in the first place, so an incorrect diagnosis may have been made.
  
• There is inadequate evidence that any cure took place.
  
• Or, the cure was amenable to subjective interpretation (such as pain, or how well someone could walk).

Someone wryly observed, for example, that there are many crutches and walkers at Lourdes, but no false limbs. There are no documented cases of any cure that is truly miraculuous or unexplainable. No one has miraculously regrown a severed limb, no one blind from birth or without eyes has regained sight, etc. Cancers sometimes go away on their own, however. Some people who are using crutches or even wheelchairs could potentially walk with a little will and physical therapy. And there are many people with syndromes that are ultimately psychological and not physical, and these are, of course, amenable to healing simply by the belief of being healed.

pedrovega

With respect to your affirmation on the false plot for the murder of JFK: Is it in your opinion the jumping bullet, that according to the Warren commission killed president Kennedy (as it was demonstrated in an unequivocal way in the Zapruder film) a scientific answer?

The "jumping" or "magic" bullet theory is nonsense, and has been disproved by careful analysis of the Zapruder film and the location of the assassination. There are many false analyses that failed to take into consideration the fact that Mayor Connally's seat was situated below that of JFK (not on the same level), or arbitrarily moved the location of the entry and exit wounds.

One analysis, done by the Failure Analysis group, convincingly showed that the "magic" bullet took a straight line into JFK' back, through his neck, through Connally's forearm (as he held it up to wave his hat), and into Connally's thigh. Let me emphasize - a straight line. A close look at the Zapruder film clearly supports this, as does modern computer simulations. Here are a couple of links:

• http://mcadams.posc.mu.edu/sbt.htm
• http://www.exponent.com/multimedia/index.html
• http://www.jfk-online.com/jfk100sbt.html

Jose Luis

Can an excess of conscience of reality cause someone to become mentally ill? Do you believe in reincarnation?

I am not sure what the first question is asking exactly. If the word "conscience" was translated correctly, that means a sense of responsibility and morality. An excess of this (or any otherwise normal and healthy cognitive function) can reasonably be considered a mental illness. Most mental illnesses are simply and excess or deficiency of some emotional or cognitive function. For example, we all feel anxious and need anxiety as a natural defense mechanism. But if anxiety occurs without a cause, and is extreme and debilitating, then it ceases to be protective and becomes dysfunctional. This is one type of mental illness. One could be obsessively compulsive regarding conscienciousness, to the point of being dysfunctional, as well.

Algol.

Are you an active member of the disinformation department on Area 51?

(Assuming this question is serious and not sarcastic) That is an excellent example of an ad hominen logical fallacy (attacking the person rather than the argument) - in this case attempting to dismiss the opinions or arguments of a person by assuming they are part of a conspiracy.

Area 51 tests experimental military aircraft. There is no evidence that they are harbouring anything alien, or that they have a disinformation department. Of course, if I were a member of such a department, that's exactly what I would say also. Which is the beauty of conspiracy theories, they cannot be disproved. They can accommodate any evidence.

Belfegor

When a doctor, who has passed through prolonged learning to get his MD and to form a scientific character, says that homeopathy works, in your opinion what are causes? Ignorance or financial interest? Or is it possible that both are factors?

Unfortunately, it is possible to get through medical school without becoming a good scientist or skeptic. Much of medicine is technical, and you can learn how to become technically competent without learning to think scientifically. In my experience, the best clinicians are good scientists and good thinkers. Those who accept unscientific notion, like homeopathy, are generally bad doctors.

It is also unfortunately true that some physicians are more concerned with profit than with practicing good medicine, and may use treatment or modalities that are profitable but not valid. I think this is a small minority, but they are there. I know of some that are little more than con-artists.

By all accounts most doctors have at least a proper respect for science, and 5% or less engage in clearly unscientific practice, like homeopathy. The problem is much worse in professions that do not have a solid culture of science, a system of scientific research, or regulatory agencies grounded in science - such as chiropractic, naturopathy, homeopathy, acupuncture, etc. In these professions, the majority of practitioners are grossly unscientific.

Faquir

Do UFOs exist or are they only a product of psychosis? How it is possible that they are seen by many people simultaneously?

This question is a false dichotomy - there are other options other than real alien spacecraft or psychosis. Most witnesses are simply mistaken about what they saw. There are many objects in the sky - satellites, aircraft, balloons, rockets, reentering orbital debris, celestial objects, etc. It is easy to misinterpret an unusual or unfamiliar sighting in the sky. It is also difficult to judge distance, size, and speed against the sky, with no frame of reference.

Also, now that UFO's are a cultural phenomenon, people have flying saucers on the brain, so there is a host of psychological factors to influence people to believe they saw a flying saucer, or to claim that they have.

It is not surprising that multiple people, all viewing the same unfamiliar phenomenon, will all misinterpret it or fail to recognize it. They will then typically discuss their mutual experience, and contaminate their memory. Their accounts will then merge onto a single story with details borrowed from each other.

There are many features of the UFO phenomenon that strongly suggest it is a psycho-cultural phenomenon. There is no evidence to support an alien phenomenon.

Gandis

Do you think that in the future we will be able to transplant brains? What class of psychological effects could that bring for the transplanted patient?

The "future" is pretty open-ended. It's impossible to predict what will be possible in a thousand years. All I could say is that this will likely not be possible within the next 100 years, beyond that is pure speculation.

Also, it might be more correct to call it a "body transplant" not a brain transplant. Since we are our brains, we would be getting a new body to house our brain. The identity would follow the brain, not the body.

Roinveg

What is the explanation for the joy experienced by attendants during a religious service (I'm an evangelist) and that I attribute to the very spirit of God that spills itself?

Our brains are clearly hard-wired for such experiences. People can have similar experiences while having a seizure, or under the influence of certain drugs, or if a part of their brains are stimulated during neurosurgery. So this is a neurological experience, not a supernatural or spiritual experience. The experience can be enhanced by other biochemical processes in the brain, such as the release of endorphins.

We can only speculate as to why we evolved such hard-wiring, but one possibility is that it has to do with the fact that we evolved in a tribal culture. It has been demonstrated to be evolutionarily advantageous to give up ones own life for the benefit of the group. Therefore, there is evolutionary pressure to feel that we belong to something bigger and greater than ourselves. We feel and desire this so intensely, in fact, that we would sacrifice our lives for the greater good. Culture built upon these evolved emotions to build society and civilization, including religions.

Eduardu

What is the role of religion in the emotional stability of a person? Does there exist any study that has determined a different function acting in the brain of believers, whichever religion they choose?

There is epidemiological evidence that religiosity correlates with happiness and longevity. However, this suffers from the same problems that all epidemiological evidence does, there are many variables and it is difficult to infer cause and effect. For example, people who are more happy may be more inclined to practice religion, rather than the other way around. Also, practicing a religion is associated with other potential social benefits, such as being part of a community and having a support network. So far these other variables have not been controlled for. There is, of course, speculation that belief meets certain psychogical needs, but others feel it also reinforces such needs. I am not aware of any studies that compare different religions in this respect.

So, at present, there is only preliminary epidemiological evidence that is impossible to interpret.

Joniale

Is it possible to genetically modify the neurons so that without destroying the existing connections of the brain (memories and conscience) they are able to reproduce themselves? Is it possible to implant "artificial" memories (or engramas) in the brain?

Right now, no. Theoretically you could either implant stem cells, or alter the physiology of neurons without changing their pattern of connections. Also, there is no technology at present to implant memories directly. This may be theoretically possible in the future.

Maikelnai

Do you support the studies involving treatments with embryonic stem cells? The defenders of homeopathy say that it does not have anything to do with the placebo effect, since it also works with babies and animals. What do you think about that?

I support embryonic stem cell research. At present, however, there is no proved stem cell therapy. So you should not believe the claims of any fringe clinics who are currently offereing stem cell treatment. They are cons.

Regarding the placebo effect, that position is very naive. The placebo effect is more complex than just a "mind over matter" effect. Part of the placebo effect is a response to the process of being treated. So the attention, and ancillary care, that a baby or animal would get as part of being treated with a homeopathic remedy or anything else could have a nonspecific "placebo" benefit. Also, the placebo effect includes an observer bias. Someone has to determine if the baby or animal got better after treatment, and their assessment could be highly biased. Also, the act of observing could have a therapeutic effect. Finally, most ailments improve on their own, so the fact that a baby or animal improved after getting a remedy may have nothing to do with the remedy itself.

The bottom line is that you can have a placebo effect, even in babies or animals, and even in people who do not "believe" in the treatment, so you still need well designed, controlled, and executed clinical trials to know if something truly has a physiological effect.

Lama

How and where does the bio-energy for "the jump" in the synapse of the dendrites takes place or "the acceptance" of the gametes? In mitochondria?

Mitochondria produce most of the energy that is used by cells for everything that they do (they produce ATP, the main energy carrying molecule, from a process of oxidation). However, some energy can be produced directly from sugar in the cell itself outside of the mitochondria (anaerobic glycolysis). The chemical energy of synaptic transmission is carried out through neurotransmitters (dopamine, GABA, serotonin, epinephrine, glutamate, etc.), which are released from the nerve terminal and bind to receptors on the receiving neuron. However, the energy to make the neurotransmitters and release them all ultimately comes from ATP made in mitochondria.

Cometo

What can you tell us about "frauds of high level"? I mean deceits or frauds made by professional scientists to institutions or other organizations (i.e. Greenglow project or others).

The Project Greenglow is a good example of crank science. In this flavor of pseudoscience, a technically skilled, and perhaps even brilliant, scientist fails to grasp the big picture. They become enamoured of their own ideas and theories, and blind to the flaws in their own research. The scientific community is likely to reject their crank ideas, especially after attempts to replicate the findings fail repeatedly. Eventually, the scientific community moves on, and the crank scientist is left to stew in their own resentment of rejection, cooking up increasing bizarre conspiracy theories to explain their own isolation.

But today, there is a cottage industry of crank science. Such pseudoscientists will find a pre-made conspiracy community ready to accept their claims with open arms, and to fill in the gaps in their conspiracy theories. The crank scientist then becomes a celebrity of the "alternative science" subculture, and has a support group to comfort them in their isolation from mainstream science.

Sometimes, like with Project Greenglow (which promises anti-gravity), a corporation (in this case Boeing) is lured by greed and the possibility of an immense technological breakthrough, to "play the lottery" by investing in a crank with grandiose claims. This may spark worry in their competitors, who do not want to be left out, and so they will fund their own research. The very fact that the claims are being researched by a respected company or institution then lends credibility to the otherwise discredited ideas, and by now the scientific community has already lost interest so at best you may get some off-the-cuff dismissals by mainstream scientists.

Typically the ideas enter into the realm of alternative science, where they can exist forever without fear of being rejected.

Now, it is possible that the crank is sincere by misguided. It is also possible that they know full well their claims are bogus, and are just trying to con a big company out of millions of dollars. Free energy guru, Dennis Lee (I think he is purely a US phenomenon) in my opinion is a 100% fraud. Others are sincere, but most are probably somewhere in between. They believe, to some extent, in their ideas, but are willing to cut corners, dismiss negative results, and exaggerate their claims in order to get the support and recognition they feel they deserve and are being cheated out of.

Moebious

Is the human brain similar to a Turing machine, whether it is determinist or not-determinist?

Sure. The brain is a sophisticated calculating machine. Consciousness, as we experience it, is a metaphenomenon, or an emergent property, of the complexity of the brain. The illusion of free will and consciousness is damn compelling, however.

By all current models, the brain is also purely deterministic. There is no random generator or non-deterministic mechanism in the brain.

Especie Desconocida

Will someday psychology be replaced by neurosciences?

The two have already merged quite a bit. In fact, historically the neurosciences evolved out of psychiatry and now they are merging again. However, I do think they will maintain their separate disciplines. The neurosciences focus on the biology and hardwiring of the brain, its physiology and biochemistry. Psychology focuses on the "software," human thought, mood, and behaviour. The two clearly overlap and influence each other, but they require different skills to deal with. I think there will always be a need for psychologists and counsellors, and their skills are different than those who diagnose and treat diseases biologically.

In the US there is a trend for psychiatrists to work together with counsellors to treat patients. The psychiatrists focus on a medical assessment and pharmacological treatment. The counsellors focus on behavioural and cognitive therapy. So far the evidence suggests that the combination of these modalities is more effective than either alone.

Kanijo

As a specialist in neurology, What is your opinion about the subject of demonic possessions and exorcisms?

I have personally investigated a few cases, and I have reviewed the investigations of many others. Incidentally, I will be appearing in a History Channel special on this topic this fall.

Most of the cases are simply people who either have a psychological disorder or a full-blow mental illness, such as schizophrenia. They develop the delusion that they are possessed, usually there is already the pre-existing religious belief in demonic possession. They then, essentially, act out what they think a possession should look like. Some have claimed that they were "cured" by exorcism, but a careful review of the cases shows that the signs of mental illness persisted beyond the exorcism, in some cases until they were treated psychiatrically.

In addition, there are no cases in which anything paranormal or supernatural is documented. Most of the cases are boringly mundane - nothing at all of interest occurs. In a few, you have a subject who screams and throws a tantrum, but nothing truly unusual happens.

Offler

Is it worth the pain and effort to try to convince those who do not want to be convinced, or the intention is to reinforce those who are already convinced?

You can break down the potential audience of skeptical writing to four groups: true believers, skeptics, seekers, and those in the middle. It is very rare to ever change the mind of a true believer. You cannot reason someone out of a belief they did not reason their way into in the first place.

For the skeptics, we serve as a source of information and entertainment. Even good skeptics need information about specific topics, and could benefit from discussions of method and logic. There is more to being a good skeptic than just having a skeptical outlook.

The majority of people are neither true believers nor skeptics. They mostly believe what they see and hear in the mass media, and may have inclinations one way or the other, but are on the fence. For these people, countering the claims of true believers is essential. Often just hearing a mainstream scientist debunking an absurd belief in enough to convince them that it is nonsense. But if they hear only the true believer side and never any skepticism, they will assume that the pseudoscience must be legitimate.

The final group are seekers, those with a specific question who are looking for information. I often encounter them when they are trying to decide whether or not to pursue a specific controversial medical treatment. This is the group we help the most, for we give them critical information at the time they need it the most. With this group, we can potentially save people from investing in frauds, subjecting themselves to harmful or useless treatments, or even getting involved in cults.

I guess there potentially is even a 5th group, and that is ourselves. I find it tremendously useful to write about these topics - it is the best way to learn. It is extremely intellectually stimulating and educational to have to put your ideas into writing, and to grapple with those who strongly disagree with your conclusions. I am a far better scientist because of my dealings with pseudoscience and skepticism. In fact my colleagues often rely upon me to help them deal with such topics.