Tuesday, August 30, 2011

Consciousness: Chapter 2 "The Spiritual Doorway in the Brain"

Have you ever wondered how you’re able to multi task so easily? Do you ever find it really cool that you can sense many things at one time? Do you know what consciousness is? One of the really interesting things about the brain is consciousness which is the state of being able to voluntarily respond to your surroundings. Imagine what we are aware of on a daily basis and what we are not. In this post I’ll be continuing my summary of Dr. Nelson’s The Spiritual Doorway in the Brain.

Think about your left leg. Before I mentioned your left leg you probably weren’t “aware” of where it was or what position it was in but now you’re thinking about how it itches or something of the like. Your mind was always aware of your foot but it was not at the fore front of your mind. According to Dr. Nelson, the brainstem functions as an on and off switch for the brain. There are three states of consciousness that the brain stem awakens: wakefulness, Rapid Eye Movement (REM) sleep, and non-REM sleep.

Dr. Nelson (the author of The Spiritual Doorway to the Brain) stated that a person has a spiritual experience when they become stuck between two of the states of consciousness mentioned above. He refers to this merging of conscious states as borderlands. A patient Nelson calls Jan found herself in the borderlands between dreaming and wakefulness when she was aware, but paralyzed by a drug during surgery.

Jan can recall exactly what happened during her surgery and exactly how badly it hurt for the surgeons to cut through her flesh (gross, I know). She went into a different state she labeled a spiritual experience (as so many of us do), during which she felt a sense of peace and the presence of her mother telling her that she was not going to die. During her surgery Jan had lost most of the blood flow to her brain. This lack of oxygen coupled with intense pain caused her to slowly lose consciousness and fall into Dr. Nelson’s ‘borderlands’.

Jan’s case, although gruesome, had the clear features of a spiritual experience: It gave her an inner peace, it lasted a short period of time, she had trouble articulating how it felt, her mother gave her a message that she would not die from this experience and it affected her life thereafter. Her experience can be explained by what we know about neuroscience as a simple physiologically induced state of mind.

What does this mean about what we should take away from these experiences? To more completely understand consciousness we have to delve into some science here. Bear with me, I promise to try to make it fun.

First, the neuron is a unique cell which communicates both chemically and electrically, and is composed of a body (soma), dendrites (usually accepts information from axons) and axons (usually sends information to dendrites). But there are also spinal nerves which project from the spinal cord to a place in your body like your left knee, this neuron works both ways. Another neuron projects from the spinal cord neuron to separate muscles which all work in tandem to move an appendage. This is actually how our reflexes work: The brain gets information about what is happening (a one way stream of information) but the task of a knee jerk reflex is handled completely by the spinal cord and not the brain.

Conversely, consciousness is the result of communication between multiple areas of the brain. A single neuron or even twenty cannot have consciousness. We’re talking about columns of cells in the cortex (outer bumpy region of the brain that we see) that can be hundreds to thousands of cells thick. The different sensations we receive, are perceived (or become aware to us) through certain areas within the brain, which are then called “active”. The activity of these brain areas are processed via the thalamus which is located above the brain stem (little lump between the brain and the spinal cord). After the thalamus processes this information, it sends it back to different areas of the cortex (the area for decision making and analysis) and then we “consciously” process the information we’ve been processing all along and didn’t really know it.

Whew! That wasn’t so bad was it?

Nelson calls the brainstem the switch for the three types of consciousness and when this switch gets stuck (something abnormal happens) the patient enters the borderland state. The brain stem is the area that Nelson really investigates during his research, which makes him different than other neuroscientists researching the same topic (it’s usually the thalamus).

Clearly, reflexes are very different from consciousness and should never be confused for one another as they seemed to be in the case of Theresa Schiavo. You may remember the woman who was in a coma years ago. There was controversy over whether or not she was actually in a permanent vegetative state. Her family wanted to believe (understandably) that she would return to normal and in their grief they misinterpreted her reflexes for consciousness.

Although her brainstem was still activating/arousing her mind, she was going to be stuck in a borderland cycling between wakefulness and REM sleep because of the part of her brain that was injured. There must be a clear line between minimal consciousness and the vegetative state, but it is hard to distinguish by just observing a patient. This is why it is necessary to use tools like PET scans and MRIs to more thoroughly understand the physiology of these patient’s brains.

The next question Nelson attempts to tackle is: Is a spiritual experience another state of consciousness? Nelson asks, “Maybe spiritual experience erupts in the borderlands between consciousnesses, unconsciousness, and dreaming—when our consciousness states are not a whole but fragmented and blended: a hybrid.” The self has everything to do with a spiritual experience given the nature of the experience. So we must tack down exactly what is this thing we call the self.

Join me next chapter: The Fragmented Self!!!


  1. I'd just like to nitpick the definition of "consciousness" that you mentioned at the top of the post, and which I assume Dr. Nelson uses: "consciousness...is the state of being able to voluntarily respond to your surroundings"

    I'm not sure this truly covers it. I would propose that consciousness also includes (but is not entirely defined by) the ability of an organism to question its most fundamental programming. For instance, we can write a computer program which produces human responses: but until it is able to ask itself WHY it is responding the way it is, I don't think any consciousness is present.

  2. I absolutely agree Brandon! This is a fundamental attribute of consciousness but you understand why I would leave it at its brevity; for the subject's sake. I could also go into much more detail about the neuroscience but I wanted to keep it as clear cut as possible. If you were interested I could explain it more completely, but privately unless there is demand for it on the blog. ;-)