The second day of the Corticon symposium started on Tuesday with discussions on neural correlates of perception, awareness and consciousness.

"Lots of synergies are created between different perspectives. Getting people to meet on these different levels [of consciousness analyses] in one conference is a very specific feature of the Human Brain Project, where it is possible to have this kind of discussion," said HBP scientist Lars Muckli from the University of Glasgow.

In his talk yesterday morning, Muckli spoke about a very faint level of consciousness. “When you hear something, you create a sense of space, and you can read this out in the visual cortex,” he said. Muckli’s approach includes knowledge that is used to fill in missing stimuli. For instance, if one receives visual stimuli that are obstructed, the subject will use the knowledge to fill in the missing parts.

Reconstructing the world around us

HBP researcher Cyriel Pennartz from the University of Amsterdam talked about a theory that says, to put it in simple terms, that consciousness is a representation. “So, we don’t see the world directly as it is, but we see a kind of reconstruction based on what the brain can make of all the sensory inputs,” he said.

These sensory inputs are coded by electrical impulses, which have no content in themselves. This means that the brain needs to generate the phenomena content we experience. Pennartz illustrated this by the so-called predictive model.

“We can imagine how one builds up from very simple models to complex, increasingly integrated models, where it has to be integrated across the senses. That’s what we tested in experiments. There’s a lot of crossing directions that might be conducive to consciousness,” said Pennartz.

Stanislas Dehaene, researcher in the HBP's lead scientist programme, discussed conscious and unconscious representations of sequences, and the search for what makes human consciousness special. He demonstrated that humans share core concepts with other primates, but only humans possess an internal “language of thought” that discretizes concepts into mental symbols, and that combines them recursively into mental programmes.

The programme continued with a public keynote lecture on the ethics of consciousness and a panel discussion on ethics and consciousness research.

Text: Helen Mendes Lima

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Corticon starts with discussions on neurocircuits dynamics and consciousness