* Ken A. Paller and Satoru Suzuki, ‘The Source of Consciousness’, Trends in Cognitive Sciences, 18 (2014), 387-9.
* Alex A. MacDonald, Lorina Naci, Penny A. MacDonald, and Adrian M. Owen, ‘Anaesthesia and Neuroimaging: Investigating the Neural Correlates of Unconsciousness’, Trends in Cognitive Sciences, 19 (2015), 100-7.

The thing about consciousness is… even though it’s a very difficult thing to know better, we need to keep trying. Two recent essays in Trends suggest ways towards progress.

Paller and Suzuki are optimistic that neuroscience can contribute to the subject. One principle for further investigation is that multiple approaches, including dealing with different brain regions and the connectivity between them, are require for dealing with something that is becoming ‘more understandable, although no less amazing’. For me their most arresting observation was about ‘the benefits that this knowledge could bring for society… continuing efforts could characterize types of neural interaction that are essential for consciousness, and thus [among other things] inform concerns about human and animal rights’. Rather than trying to identify the neural mechanisms for consciousness in a positive way, they suggest, it might be easier to look for those mechanisms without which consciousness cannot happen.

*

MacDonald et al. also advocate a negative route to understanding consciousness. Their idea is that studies of anaesthetized patients, where consciousness is lost but other processes in the brain continue, might offer ways of defining what the crucial components are. In anaesthesia it has been shown that simple sensory processes continue, but that other higher order functions stop, especially those which provide connectivity (again) between regions in the cortex that are responsible for the simpler processes.
      Their focus is partly on ‘disorders of consciousness’ – as in patients in vegetative states – where it is of great (and disquieting) importance to ascertain how much consciousness persists. They conclude that ‘neuroimaging evidence for simple sensory processing does not provide any support for preserved conscious awareness’, but ‘functional connectivity between distant cortical regions, particularly between frontoparietal cortices, and/or activity in association cortices in response to complex cognitive processing, does appear to require conscious awareness’. If such connectivity is observed in otherwise unresponsive patients, they may need special attention.
      I have already suggested, in this post, that one literary means of enhancing our understanding of human consciousness is to represent very different kinds of consciousness. I suppose that these experiments have an indirect strategy that’s not all that different. And soon I am planning to write an essay about the boundary between life and lifelessness, consciousness and a lack of consciousness, in Shakespeare. An audience has to think about what changes across that boundary as Lear dies or as Thaisa revives. Instead of activation picked up by fMRI, drama offers different signs, some easier to perform than others, that the fictional mind in question has gained or lost awareness. I hope to show that these signs matter.