Exploring the edge of consciousness

Two new online articles explore the brain centres that may be responsible for self-awareness.

The first article begins with the question, how do we become conscious after sleep? The question can be rephrased to ask what brain areas become more active as we wake and regain normal self-awareness.

Whatever your definition of consciousness, or your opinion of brain scan studies, unless you’re up for some form of dualism there’s no real disputing that every cognitive state is associated with specific brain processes.

Science Daily published online a summary of new research into the brain states of “lucid dreamers,” people who, though asleep, are aware that they are dreaming and whose brain activity at the moment of achieving this “dreaming awareness”  is more easily measured than is the brain activity of typical, non-conscious dreamers.

Please note that this research is not at all connected to the pop psychology popularity of meditation and “dream control” that you can find on self-help websites all over the internet. These people are real scientists. Because the brains of typical dreamers are in a state of low activity when consciousness first returns after sleep, it has been impossible until now to identify specific brain regions associated with consciousness.

The article, titled “Lucid Dreamers Help Scientists Locate the Seat of Meta-Consciousness in the Brain,” was published on July 27th.

Researchers from Munich, Leipzig and Berlin used magnetic resonance tomography “to demonstrate that a specific cortical network consisting of the right dorsolateral prefrontal cortex, the frontopolar regions and the precuneus is activated when this lucid consciousness is attained.”

Each of these brain regions has been shown in previous studies to be associated with “self-reflective functions.” The current study provides the first empirical evidence of which areas of the brain are particularly active when self-awareness occurs.

“The general basic activity of the brain is similar in a normal dream and in a lucid dream,” says Michael Czisch, head of a research group at the Max Planck Institute of Psychiatry. “In a lucid state, however, the activity in certain areas of the cerebral cortex increases markedly within seconds.

A second article, published by New Scientist on July 23rd, highlights a different part of the search for the mechanisms that produce self-awareness.

“Are these the brain cells that give us consciousness?” highlights “an odd kind of brain cell involved in emotions and empathy that may have accidentally made us conscious.”

These cells, known as von Economo neurons (VENs) after the scientist who first described them in 1926, are larger and differently shaped than are typical neurons. Unlike most neurons, VENs have only a single dendrite (connector) at each end. VENs are very rare, making up only 1% of the neurons in two small brain areas, the anterior cingulate cortex (ACC) and the fronto-insular (FI) cortex.

The ACC and the FI are part of what John Allman of CalTech calls the “social monitoring network.” Activity in these brain areas ramps up when we encounter “socially relevant cues” and when we experience “emotions like love, lust, anger and grief.”

Both areas are also active when we look at our own reflections in a mirror, suggesting that they are part of the brain process that produces self-consciousness.

To Bud Craig, a neuroanatomist at Barrow Neurological Institute in Phoenix, Arizona, it all amounts to a continually updated sense of “how I feel now”: the ACC and FI take inputs from the body and tie them together with social cues, thoughts and emotions to quickly and efficiently alter our behaviour.

To Allman and neuroanatomist Bud Craig, the VENs’ size may show their importance:

In the brain, big usually means fast, so Allman suggests that VENs could be acting as a fast relay system – a kind of social superhighway – which allows the gist of the situation to move quickly through the brain, enabling us to react intuitively on the hop, a crucial survival skill in a social species like ours. “That’s what all of civilisation is based on: our ability to communicate socially, efficiently,” adds Craig.

The article goes on to speculate that since VENs are also present in advanced social species like gorillas, elephants, and dolphins they may be a crucial part of social awareness — and, as such, a key component of self-awareness.

While VENs are also present in less social species like hippos and giraffes, it is not unreasonable to speculate that they may have started out with one function and evolved to facilitate social networking in those species that became social.

Of course, there is much educated guesswork involved in any move from what it is and how it works to what it’s for and why it’s there. Our understanding of consciousness is not yet sophisticated or complete enough to let anyone say with certainty just what does what.

What we do know, for sure, is that there is a physical basis to everything that we call cognition. So we just have to keep digging, and hope that our minds don’t turn out to be too much like Nova Scotia’s Oak Island.

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