Daniel Dennett

From an interview with Chris Floyd
Science & Spirit

Edited by Andy Ross

My views on consciousness are initially very counterintuitive. Those whose curiosity is piqued by what I say here are beseeched to consult the long version carefully. Aside from my books, there are dozens of articles available free on my website.

Consciousness is not some extra glow or aura caused by the activities of the mature cortex. Consciousness is those various activities. One is conscious of those contents whose representations briefly monopolize certain cortical resources, in competition with many other representations. So consciousness is fame in the brain, or cerebral celebrity. Those who claim they can imagine a being that has all these competitive activities in the cortex but is not conscious are mistaken. They can no more imagine this coherently than they can imagine a being that has all the powers of a living thing but is not alive.

There is no privileged center, no soul, no place where it all comes together, aside from the brain itself. A conscious human soul is not a thing, but a way of being organized and maintaining that organization.

The hidden agenda for most people concerned about consciousness and the brain is a worry that unless there is a bit of us that is somehow different, and mysteriously insulated from the material world, life will have no meaning.

There are no factual assertions that religion can reasonably claim as its own, off limits to science. Many who readily grant this have not considered its implications. Religion plays a major role as a source of moral injunctions and precepts, but it does not set the ground rules of ethical agreement and disagreement.

Ceremonial speech play a huge role in stabilizing the attitudes and policies of those who participate in them, but ceremony without power does not appear to be a stable arrangement. Religious people will seldom acknowledge in public that their God has been reduced to a mere constitutional monarch.

Many people who profess belief in God do not really act the way people who believed in God would act. They act the way people would act who believed in believing in God. They manifestly think that believing in God is a state of mind to be encouraged, so they defend it.

Once nothing follows from a belief in God that doesn't equally follow from the presumably weaker creed that it would be good if I believed in God, God can coexist peacefully with science. So can Santa Claus.

AR I compared Dan Dennett with Santa Claus in my JCS report on the 2002 NYAS meeting The Self: From Soul to Brain.

Flesh Made Soul

By Sandra Blakeslee
Science & Spirit

Edited by Andy Ross

Martin Paulus says a new description of how the human body and brain communicate to produce emotional states can explain how the human brain might give rise to spiritual experiences. Called interoception, it offers a radically new view of human anatomy and physiology based on how information from the body reaches the brain and how that information is processed in humans.

Arthur D. Craig says the subjective awareness of our emotional state is based on how our brain represents our physiological state. The brain's centers that integrate sensory reports from the body are found to be highly active in studies of drug addiction, pain in oneself, empathy for others, humor, seeing disgust on someone's face, anticipating an electric shock, being shunned in a social setting, listening to music, sensing that time stands still, and contemplating compassion. So spirituality can be explained in terms of brain physiology.

William James said we run from a bear not because we are afraid but because we have a racing heart, tight stomach, sweaty palms, and tense muscles. But the neuroantaomical details of how such signals from the body produce feelings and motivations have only recently been worked out. It turns out that the brain exploits several pathways for knowing what the body is up to.

One involves touch. Human skin contains receptors for gentle pressure, deep pressure, sustained pressure, hair follicle bending, and vibration. When one of these touch receptors is activated, fast moving signals are sent to the brain's primary touch map, where each body part is faithfully mapped out. A touch on the arm activates the brain's arm map. A touch on the cheek activates the brain's cheek map, and so on for every inch of the human body.

Skin, muscles, and internal organs contain other types of receptors that collect an ongoing report about the body's felt state. Thus there are receptors for heat, cold, itch, tickle, muscle ache, muscle burn, dull pain, sharp pain, cramping, air hunger, and visceral urgency. This collective interoceptive information represents the condition of the body as it strives to maintain internal balance.

Whereas touch signals for pressure and vibration are carried on fast acting fibers to the primary touch map, interoceptive information is carried up the spinal cord and into the brainstem via a wholly different network of slow acting fibers. This information about the body's felt state goes to a region of the brain called the insula.

The insula in the brain is devoted to feeling interoceptive sensations from the body. It is connected to the anterior cingulate, which produces actions responding to those feelings. Both the insula and anterior cingulate are wired to the amygdala, hypothalamus, and prefrontal cortex, which allow the brain to make sense of what the body is telling it.

Humans exploit this wiring to generate complex emotions that other animals cannot fathom. Those animals cannot experience feelings from the body in the way that humans do, Craig says. Our frontal insulas are huge compared to other primates. Social emotions are a hallmark of humankind and interoception is what allows us to feel them.

Social emotions are a mixture of positive and negative elements that activate the right and left frontal insulas differently. In general the right insula is involved in energy expenditure and arousal whereas the left insula is associated with nourishment and love. Thus when empathy involves a challenge, the right insula is more active than the left. When empathy involves compassion, the left insula is more active.

As the right frontal insula collects information from the body, it builds up a set of emotional moments through time. An emotional moment is the brain's image of the self at any point in time and is, he says, the basis for our subjective emotional awareness. Sometimes, in extraordinary moments, our awareness is heightened and everything seems to unfold in slow motion. Heightened awareness produces an emotional moment so large it alters the perception of time.

The right hemisphere contains circuits for recognizing and feeling the self. Imaging experiments show that the medial prefrontal cortex, precuneus, and posterior cingulate cortex light up in imaging studies when subjects think about themselves, their hopes, and aspirations and retrieve episodic memories related to their lives. When the circuit is suppressed with a transcranial magnet, people no longer recognize themselves in a mirror.

Buddhist monks focused on compassion show a dramatic increase in insula activity and their anterior cingulates show less activity, suggesting the monks attain a state of awareness without motivation. Paulus says the focus on interoceptive experiences is a central aspect of meditative practices in certain Zen schools.

Andrew Newberg studies Buddhists using single photon emission computed tomography. The method shows decreased activity in the parietal lobe when the monks meditate. Franciscan nuns at prayer showed a similar decrease of activity in the parietal lobe, which uses sensory information to create a sense of self and relate it spatially to the rest of the world. When they pray, they lose themselves.