Never mind? In keeping with the policy of the Humanist to accommodate the diverse cultural social, political, and philosophical viewpoints of its readers, this occasional feature allows for the expression of alternative, dissenting, or opposing views on issues previously broached within these pages. (Creative Controversy).

Editor's note:

Is science really becoming able to read minds--or at least read minds in the act of reading? That seems to depend on how one defines mind, how one defines reading, and what level of precision is being claimed. In the following exchange, psychologist Bruce H. Hinrichs responds to his critics--then two of his critics find areas of agreement and disagreement as they sum up the controversy.

I'M THE AUTHOR of "The Science of Reading Minds' in the May/June 2001 Humanist and wish to comment on a letter and essay published subsequently in response to my article --responses with which I have major disagreements.

A letter from neurologist D. S. Summers in the July/August issue stated that my conjectures "lie within the domain of the paranormal or pseudoscience." I find this insulting, since I have great distaste for such crackpot notions. Quite the contrary, my article is based on current scientific research, although I admit to raising provocative (and I thought, amusing) conjectures regarding the ramifications of future possible uses of brain-imaging technologies. To avoid similar complaints, I will include the names of the researchers.

Summers states that brain-imaging technology cannot detect thoughts because it merely measures "physiologic (electrical) dynamics ... but can't be extrapolated beyond configurations and frequencies." This statement is demonstrably false; but even worse, it reeks of the quaint (though wildly popular) view that the mind is a nonphysical thing--a spirit that is not part and parcel of the physical stuff of the brain. This dualist view is 350 years old and quite ridiculous. Thoughts don't exist in some supernatural world but consist of the physiological happenings of the brain. There is no ghost in the machine. A device that reads "physiologic dynamics" and produces "configurations and frequencies" of brain activity is precisely what is necessary to read the mind. What else would be needed?

Summers further insists that reading thoughts is "an impossibility." It seems odd that a self-proclaimed freethinker would use words such as can't and impossibility without checking the evidence. In fact, this "impossibility" has already been accomplished, albeit only at a modest level.

Similarly, in an article in the September/October 2001 Humanist, psychiatrist Nashaat Boutros and physiologist David Schafer state that mind reading by technology is "absurd when you consider that even the simplest thought, word, or idea is represented in the brain in a coded message involving the integrated functioning of perhaps thousands of neurons in very different parts of the brain." Well, the idea can't be terribly absurd--since it's already been done! Also, it is amusing and paradoxical that Boutros and Schafer state unequivocally what the physiological basis of a thought is (how in the world do they know that?) yet then claim there is no possible way to identify such a physiological basis. Hmmm?

Scientists don't yet know the precise physiology of consciousness, although Arash Sahraie, Michael Posner, Nikos K. Logothetis, William T. Newsome Roger Tootell, and many others have identified areas of the brain, and even specific neurons, that are part of the process of creating awareness. The entire physiology of consciousness is not yet known, but that doesn't mean that it can't be known. Every bit of logic and empirical evidence leads to the conclusion that we will eventually uncover the biological correlates of mental experiences.

Whether or not thoughts are distributed in "very different parts of the brain," as Boutros and Schafer contend, is currently unknown. Likely, it depends on one's definition of thought and on the nature of each particular thought. Indeed, some thoughts may be very localized. But if thoughts are the result of widely distributed brain networks, then how are they united or bound? Brain waves may be the means by which a brain unifies disparate areas of activity--a hypothesis in vogue among many cognitive neuroscientists (for example, Francis Crick and Terrence Sejnowski). If such is the case, then electroencephalogram (EEG) may be the best indicator of thoughts that we have. More to the point, it has already been experimentally demonstrated that thinking a simple word or sentence elicits a highly identifiable brain wave pattern.

Patrick Suppes and his team at Stanford University have been able to mathematically manipulate EEG recordings to identify with great accuracy what simple word, sentence, or image subjects are thinking. They wrote:

   Brain-wave recognition of words and simple sentences being processed is
   feasible.... the very best results obtained of 97% and 91% correct
   recognition are encouraging.... we are confident that the present
   brain-imaging technologies available are sufficient to permit continued
   scientific progress by us and others in recognizing and understanding what
   the brain is processing under conditions of conscious awareness.

So, what my detractors have called absurd and an impossibility is, in fact, a reality. Simple thoughts have been identified using EEG.

Another concern I have is the use of the word represented by Boutros and Schafer. Are they implying that thoughts exist outside of brain functioning and are merely represented by physiological functions? What are thoughts if not products of the brain? It is my position that conscious thoughts are produced by brain activity, and therefore can be "read" if we understand what their particular physiology is.

Boutros and Schafer also state that the "coding" (the term they use for the physiological "representation" of a thought) "may differ from person to person and in a single person from time to time or under different conditions." But this is wrong; it isn't what Suppes found. In his experiments, the same brain sine waves were overwhelmingly found from person to person and in the same person when reading the same word or sentence. He and his team report:

   Superposed prototypes [of brain waves] constructed from averaging not only
   data from different trials and subjects but clearly different
   stimuli--visual image, visual name, and spoken name--recognized without
   error the unfiltered test samples.

That is, when you and I read the word "yes," we produce brain waves that are identical enough to be identified with great accuracy using mathematical filtering techniques.

Let's consider it logically: Why wouldn't we have the same brain waves when thinking the same thoughts? Would evolution have produced brains that use radically different physiology for the same purpose? When you and I look at a blue object, the same types of photoreceptors in our eyes are stimulated, the same neural pathways are activated, and the same physiological processing occurs. Isn't it reasonable that our brains would elicit similar brain waves when having the same experience?

Boutros and Schafer not only argue that identifying thoughts with an EEG is absurd, they also give the reason that it's because brains are too complex. Sadly, this reasoning comes dangerously close to the arguments of theorists known as mysterians, who claim the brain is just a big mystery that we can never understand. Yes, brains are complex. But they aren't infinite. Brain-imaging technologies are now capable of identifying people's moods, temperaments, various types of memory, perceptions, and numerous other mental states. In monkeys, microelectrodes have recorded the individual neurons that fire when visual perception shifts from one interpretation of a stimulus to another (David L. Sheinberg). Corresponding brain sites have been identified in human subjects (Sahraie). Two independent studies (James B. Brewer and Anthony D. Wagne found that the amount a person later remembered could be predicted by looking at activity in the brain's hippocampal region during learning. William Marslen-Wilson and Lorraine Tyler were able to identify different brain areas for storing regular and irregular past tenses of verbs. The brain areas that process nouns and verbs are separate from one another and have been identified (Antonio Damasio). In fact, the anatomical cascade that occurs during reading has also been mapped (Posner). Joseph LeDoux has traced the neural pathway of an emotion in rats' brains. Antonio and Hanna Damasio have identified important emotional centers in human brains. The brain cells that detect visual movement, color, and form have been mapped (Posner). What an object is and where it is located are processed in different brain areas (Fraser A. W. Wilson). Memories have been traced (David J. Krupa). The brain area for perfect pitch has been identified (Rachel Nowak). Recent research has identified brain areas that are active when people make various kinds of moral decisions (Joshua D. Greene). There are thousands of similar findings.

Quantum physics is complex, but scientists still can identify the presence of a muon. While brains certainly are complex, this doesn't mean we will never be able to identify the anatomical and physiological underpinnings of mental phenomena. In fact, as the few examples above attest, current technologies right now allow for a good deal of "mind reading," depending on how broadly one defines mind and how much precision is demanded.

In the next few decades we might not be able to use brain imaging to determine precisely what a person is thinking in every instance, but we will very likely be able to identify moods, depression, various emotions and cravings, general domains of thought, whether a person has a false memory, whether a lesson has been learned, whether a person is hungry, and similar dimensions of the mind. Computer expert Raymond Kurzweil even predicts that in thirty years we will be able to use nanotechnology to download our minds into machines--a process he calls reinstantiation. Our minds will exist in a medium outside our brains. Would you like to be reinstantiated?

I am somewhat disappointed that the pun in the title of my original article was overlooked. I intentionally referred to the science of "reading minds" (that is, minds in the process of reading) because Suppes and his team scientifically measured brain activity while subjects read. They wrote:

   The recognition rates reported here further strengthen the case that
   recordings of electric brain waves of words or sentences, together with
   extensive mathematical and statistical analysis, can be the basis of new
   developments in our understanding of brain processing of language.

Unfortunately, the responses to my article have focused on "mind reading" instead of "reading minds"--a distinction I appreciate.

Boutros and Schafer confidently write that "studies of the localization of brain functions have not yet begun to crack this code [the physiology of thoughts] and aren't likely to do so any time soon." Of course, it is a matter of subjective judgment what findings would constitute "cracking the code" of the mind. In addition to the findings of Suppes mentioned above, however, there are legions of studies that have identified very specific brain regions, cellular networks, and even small groups of neurons that produce various mental phenomena.

In just one example, scientists study binocular rivalry by presenting a different image to each eye of a monkey or person. For most subjects, the mind perceives one image and then the other alternately (a person can tell us what he or she perceives, while a monkey is trained to give a signal when experiencing a certain percept). Scientists have used this procedure to identify the cells in the visual pathway that change their firing when the change in perception occurs. Presumably these are the cells that create, or help to create, the conscious perception that a subject experiences. That is, when these cells are firing, the subject has a certain percept in mind. Researchers found that they could induce a particular perception by stimulating the corresponding cells (Logothetis). Is it unreasonable to think that the brain wave pattern has also changed when the firing of cells that create a perception has changed?

Finally, Boutros and Schafer flatly state that scientists will not be able to identify a specific thought such as "I would like a drink of vermouth." They go so far as to state that such a belief is "totally unfounded." Unfounded? Are they unfamiliar with current research? When it comes to identifying that particular thought, perhaps they are right. But how can they be so sure? What is preventing such an identification? Frank Schneider identified the neural correlates of alcohol craving. Suppes found that an EEG sine wave could identify (with a high rate of success) when subjects were thinking a particular word (for example, right, left, yes, blue), image (for example, the color blue, which incidentally produces the same sine wave as the word blue), or sentence (for example, "Bill sees Susan").

If such thoughts can be "read," is it so unreasonable to believe that we will be able to identify when a person is thirsty (certain hypothalamic activity), and is simultaneously thinking about vermouth (certain brain wave pattern)? Well, is it? If you think it is unreasonable, then never mind. Otherwise, pass the vodka.

Bruce H. Hinrichs is a professor of psychology and humanities at Century College in Minnesota. He is the author of Mind As Mosaic, an introduction to cognitive neuroscience.