Is There Someone Else In There? Exploring the Possibility of Multiple Consciousnesses

It’s impossible, of course, to say with certainty that this theory is right (or wrong.) But I think most readers would agree that it correlates to our general sense of our self—that we are made up of personality parts and they combine in different ways to create a unit. And if we accept that, we may then entertain a more disconcerting thought, that there may be different selves within our minds.  

Dissociative Identity Disorder
The most obviously evidence for multiple selves in one mind would be the diagnosis of dissociative identity disorder (DID) (previously called multiple personality syndrome.) We've seen this one on screens big and small with the made-for-television movie Sybil being the classic example. In DID a seemingly normal person is suddenly overtaking by a completely different (often aggressive) personality—a Hyde to a Jekyll. In some cases, additional personalities may appear.  

That's how it works in the movies anyway. How does this disorder appear in the real world? This Psychology Today page outlines the traits of the diagnosis.

DID reflects a failure to integrate various aspects of identity, memory, and consciousness into a single multidimensional self. Usually, a primary identity carries the individual's given name and is passive, dependent, guilty, and depressed. When in control, each personality state, or alter, may be experienced as if it has a distinct history, self-image and identity. The alters' characteristics—including name, reported age and gender, vocabulary, general knowledge, and predominant mood—contrast with those of the primary identity. Certain circumstances or stressors can cause a particular alter to emerge. The various identities may deny knowledge of one another, be critical of one another or appear to be in open conflict.

That said, the identity transitions that over take a person during DID have been observed during brain scans. And the diagnosis remains in the Diagnostic and Statistical Manual of Mental Disorders published by the American Psychiatric Association.  

Let's consider DID as possible evidence of the existence of multiple selves in one body. Fortunately, there is more compelling evidence.  

Split-Brain Experiments
Neuroscientist Mike Gazzaniga cemented his place in history when he participated in the famous split-brain experiments. The experiments were a series of psychological tests conducted on epilepsy patients whose brain hemispheres had been surgically separated. Despite this rather dramatic procedure, the patients seemed normal to the casual observer. Experiments conducted by Gazzaniga and others, however, teased out intriguing deficits of these patients.  

In the experiments, scientists would present a split-brain subject’s individual brain hemispheres with a specific visual prompt. The subjects were then asked to report what they saw. The verbal left hemisphere could easily do this. If it had been prompted with an apple, the person would report seeing an apple. The right hemisphere, which lacks language functionality, could not and the patient would claim—speaking via their left hemisphere—to have seen nothing. However, the patient’s left hand—connected to the right hemisphere—could draw the prompted object. When asked why they had drawn the object seen in the prompt, the subject’s (talking left hemisphere) would confabulate a reason, making something up to explain this seemingly odd behavior.  

(I realize these experiments are hard to visualize. This illustration from Nature magazine is very helpful. The article the illustration accompanies describes the experiments in detail.)  

The experiments have been conducted many different times in various forms but the general takeaway remains the same: split-brain patients seem to possess two different minds. One is verbal and housed in the left-brain. The second is non-verbal and housed in the right. The two selves seem to be unaware of each other and can only be revealed by carefully designed experimentation.  

You might find this intriguing but ask, "What does this have to do with the rest of us who don’t have our brain hemispheres separated?” Well, more than you think.  

We Are All Split Brain Patients Now
The neuroscientist Sam Harris, in his book "Waking Up," tackles some of the philosophical challenges prompted by the split-brain experiments. In doing so he focuses on the corpus callosum—the piece of brain tissue that connects the right and left hemispheres of the brain and is severed in split-brain surgery. In non-split-brain individuals (e.g. most of humanity) the corpus callosum’s job is to consolidate the two hemispheres into a whole. But here's the catch: the corpus callosum cannot fully integrate the two hemispheres. It most likely lacks the neural "bandwidth" for such a task. As Harris explains… (My comments in [].)

Given the immense amount of information processing that takes place in each hemisphere, it seems certain that even a normal human brain will be functionally split to one or another degree. Two hundred million nerve fibers [the bandwidth of the corpus callosum] seem insignificant to integrate the simultaneous activity of 20 billion neurons in the cerebral cortex, each of which makes hundred or thousands (sometimes tens of thousands) of connections to its neighbors.

The ramifications of this are shocking. It means that inside your head are two consciousnesses (at least.) One, the verbal left hemisphere, is reading these words and running an interior commentary. The second, the non-verbal right hemisphere, is doing... well, who knows what it's doing?  

The philosopher Roland Pucetti has an idea. He claims that the right hemisphere has long understood that it is attached to a more dominant partner and has acquiesced to the situation. Quoted in "Waking Up," Pucetti says.

The non-speaking hemisphere has known about the true state of affairs from a very tender age. It has known this because beginning at age two or three it heard speech emanating from the common body that, as language development on the left proceeded, became too complex grammatically and syntactically for it to believe it was generating… Being inured to this status of cerebral helot, it goes along. Thankless cooperation becomes a way of life.

Other Selves
Not all theories of multiple consciousnesess are so tied to the geography of the brain. Sigmund Freud, of course, famously believed in a hidden part of man's psyche called the subconscious. While many of Freud’s theories have defied scientific validation (penis envy, for instance), the general consensus is that he was on to something with the subconscious. Numerous experiments in phenomenom such as priming and blindsight illustrate a non-conscious aspect to our decision-making and life experience.  

Dr. John Sarno was a physician who argued that the chronic pain his patients suffered were caused by the subconscious mind. Certain kinds of pain are, in Sarno's formulation, an attempt to distract the mind from repressed emotional issues. Some patients overcome their pain in part by talking to their subconscious, as if it were another entity living inside them. Here’s a quote from a man who used Sarno's ideas to treat severe back pain:

Any time I was facing pain, I would consciously think to myself something along the lines of: "Hey you, unconscious mind, I know what you're doing. I know full well that this is not a physical condition, but merely trickery designed to distract me from something else. You are not fooling anyone, and it's not going to work. Stop it now!" Whether this actually sent a signal to my subconscious is something I can't know, but I do know that the mere act of trying to talk my subconscious down in this manner was extremely effective at resolving many pain episodes quite rapidly.

I found it difficult to come to terms with, and adjust to, the cunning and sophisticated nature of my subconscious. It knew before I did that there were troubling thoughts or concerns brewing in my mind, and would deliberately inflict pain in order to prevent those thoughts from becoming conscious.

What is a self, anyway? Part of the problem here is that we are dealing with intangibles. There is no physical quality to the mental self that we can measure or count. There is no way we can view the geography of the mind and track its borders. At best, these various theories can be thought of as metaphors used to understand the incredibly complex and formless construct that is the human psyche.  

We, of course, feel like a complete unit. But perhaps that’s simply the story we tell ourselves. Perhaps our minds are made up of various “parts”—mind modules, ids and egos, whatever—and most of us tell ourselves that the parts add up to one. But some people may view these parts as comprising two selves. Others still may feel their self is one small part of a larger unit such as a universal consciousness. How we do the math is somewhat arbitrary, and ultimately doesn’t really tell us much.  

All these ideas do point to certain truth, that there is a lot more going on in our minds than might first appear. A plethora of hidden voices wield their influence, affecting our decisions, our conflicts, our moods and our feelings. Sometimes these voices point us towards important truths; at other times they steer us astray. Learning how to hear these voices and determine whether to follow their call is a skill that can take a lifetime to develop. And it may be the most important skill of all.