In song and story the mind works as a stream of consciousness. Maybe not. Maybe it’s like a film, 24 frames per second but we perceive it as a continuous stream? Maybe it’s something else…like waves perhaps? Or, according to a recently published study from the University of Illinois (USA), at least the visual function of the brain may ‘see’ in a rhythmic series – as waves and frames.

The researchers came to this conclusion after conducting tests to measure how much people observed of small events occurring in short periods of time. In a first round of research in 2009, they used a flashing but dim light at various intervals. They noted – as people sometimes do in real life – that some of the flashing lights were noticed, at other times not. In traditional neurology this missing of details, even repeated flashing of colored lights, was ascribed to ‘lack of attention’, ‘random thought interruption’, or just ‘neural noise’. The researchers thought otherwise. There was a pattern to what was seen when, a rhythm.

After establishing that there was a regularity to perception, that lights were noticed or not noticed in more or less regular sequence, they wondered if this rhythm could be in some way influenced – the word used by psychologists is entrained. Did the mind automatically change rhythms to match a situation so that important details would not be missed? Could this be stimulated artificially?

The answer was, yes. The second experiments involved a faint, rhythmic light followed immediately by a second light that masks the first light so that only the second light is the one seen. The first light is ‘lost’ as a matter of visual information. The technique is called backward masking. The subjects were then told about the first light and told to concentrate on the rhythm of flashes so that they could see the first light – their perception then became entrained. This was the first time in a controlled experiment where the rhythm of visual cognition was trained to make visual perception intentionally focused. This implied that the rhythms and frames used by the brain as part of the ‘filtering’ of reality – the ways used by the brain to avoid sensory overload – and may be common to other brain functions.

“There is this idea that we look out into the world and see this ongoing flow of consciousness that has been compared to a stream,” says Kyle Mathewson, lead author of the paper that appears in the journal Cognition. “This evidence and other evidence are starting to show it might not be like that, it might be more discrete.”

“We’re just flashing something on the screen but if you think about it many of the things around us are rhythmic: our speech has certain rhythmicity to it, cars moving down the street, movement has rhythmicity to it,” Mathewson said. “So this might be a more common mechanism throughout the brain by which the brain starts to process the environment because it picks up on the rhythmicities that are everywhere.

And that means a research line that has many possibilities.

[Source: Futurity]

Many possibilities indeed, as it may turn out many processes in the brain are rhythmic, timed, waveform, cyclical – and partial (discrete) – not continuous, as in stream of consciousness. More like the rhythm of consciousness.