Decoding the cryptic connection between the brain's architecture and our consciousness

Imagine an alien spacecraft landing on Earth, a mysterious entity unlike anything ever seen before. Now, envision our brain as an intricate spaceship, and the researchers in the COST Action The neural architecture of consciousness (NeuralArchCon) as brilliant engineers determined to crack its inner workings. This spaceship is a good analogy for what we all carry around in our heads. But amid this exploration, a question arises: Will computers ever achieve consciousness?

In this article, we follow Dr Kristian Sandberg, the Chair of NeuralArchCon from Aarhus University, as he guides us through their mission: to decode the cryptic connection between the brain's architecture and our consciousness - the very fabric of thoughts, feelings, and awareness that defines our existence. Their goal? To improve our brain's navigation system and make our journey through life smoother. He also gives us his answer to the intriguing question of computers and consciousness…

Brain data and behavioral data

According to Dr Sandberg, about 95% of human neuroimaging consciousness research focuses on ongoing activity. "This is critically important work," he says, "but it can also be compared to trying to understand a computer without examining the components".

NeuralArchCon is one of the few large-scale efforts specifically aimed at understanding the relationship between the hardware of the brain and conscious experience. Understanding this link will not only benefit mechanistic explanations of consciousness but may also prove relevant to disorders of consciousness.

Previously able to study only the neural basis of conscious vision, the researchers have now been able to expand both the range of conscious phenomena and the levels of biology studied. By combining broad behavioural phenotyping with brain scans, genetic profiling, and quantification of blood metabolism, they are now taking the first steps towards deep phenotyping of consciousness.

A new level of the neural architecture of consciousness

A major change in the field since 2019 when the Action started, is sample size. That is, how many participants are needed to study the architecture of the brain? Whereas earlier studies often used just a few dozen participants, more recent studies suggest that hundreds or thousands are needed. Of course, the sample size depends on the quality of the data. The Action NeuralArchCon anticipated this debate and designed its project to combine large sample sizes with high-quality data.

Challenges

The biggest challenge for the Action, according to Kristian Sandberg, was the outbreak of the COVID-19 pandemic shortly after the start of the Action. This was particularly challenging for an network like NeuralArchCon, whose success depended on large-scale testing with human participants. Fortunately, the Action was able to restructure its workflows and change plans for researcher mobility to allow time for COVID-19 testing and/or quarantine. As a result, researchers were able to complete their experiments between lockdowns with far less disruption and delay than they had feared. "It was a massive effort, particularly by many of our early career researchers", says Kristian.

Another challenge that the Chair remembers was the setting up of large-scale experiments at the first data collection site. "Normally with small-scale experiments, we can always go back and fix a bug and it is no big deal", he says, "but in this case, when we are running 15 experiments in parallel, a bug in one means we have to start from scratch, so the pressure was immense to get everything up and running. But our network came together and solved all the unforeseen problems so we could continue without delay. The amazing thing was that once we had all this sorted out at the first data collection site, scaling up and expanding to other sites became much easier and the local teams were able to overcome all the challenges", concludes Kristian.

NeuralArchCon's breakthroughs in consciousness research

The NeuralArchCon Action has assembled a comprehensive neuroscience dataset on consciousness, with over 1000 hours of brain scans and nearly 10,000 hours of behavioural testing from nearly 1000 participants. This rich resource facilitates collaborations of all sizes and provides researchers with access to advanced neuroimaging and genetic data. The project is designed to explore diverse phenomena of consciousness, including perceptual modalities, memory, and mental imagery. In a recent publication, the Action researchers explored the concept of 'mind blanking', challenging the notion that our minds are always busy. Using functional MRI and experience sampling, they uncovered synchronised brain activity during mind blanking, suggesting a unique default mental state.

Another study within the Action focused on the link between mindfulness and nightmares. Higher mindfulness scores correlated with fewer nightmares, suggesting that practices such as meditation and lucid dreaming training could reduce the occurrence of nightmares.

The NeuralArchCon dataset is proving to be invaluable, enabling interdisciplinary insights and innovative research avenues. For example, the data allow novel connections to be made between archetypes of consciousness and music perception. Action members have incorporated subjective pleasure in music perception into their questionnaire data, leading to collaborations with prominent music researchers. In addition, paradigms involving subjective reports of confidence are contributing to the study of metacognition, exploring its domain specificity or generality.

Recognizin excellence: NeuralArchCon follow-on grants

Several members of NeuralArchCon have received grants closely linked to the Action research, in particular for the analysis of Action data. Dr Renate Rutiku received a €550,000 grant to investigate integration across the perceptual hierarchy using psychophysics, EEG and MRI, while Dr Elisa Filevich was awarded around €500,000 to investigate motor metacognition in music learning. In addition, Dr Per Qvist was awarded €270,000 to investigate genetic and blood signatures within the NeuralArchCon cohort. Dr Timo Kvamme and Dr Kristian Sandberg received grants totaling around €175,000 to investigate the neural architecture of conscious experience during mental imagery. Dr Claude Bajada received a €50,000 grant to focus on linking neural architecture to consciousness. These grants reflect a diverse range of studies aligned with the aims of NeuralArchCon and will make a significant contribution to advancing research in the field.

Personal journey and professional growth in NeuralArchCon

"It has been very rewarding to see how the Action has continually expanded my professional network", says Kristian Sandberg. "When we submitted the proposal back in 2018, I had to rely on colleagues to help invite other colleagues to build a collaboration of the scale we wanted, and the network of proposers was relatively homogeneous in terms of scientific and demographic profile. The fact that people could join the Action after it had started worked exceptionally well, and NeuralArchCon grew considerably in the first couple of years. It has been particularly rewarding to see people with different profiles joining and how this has taken our collaboration in new and interesting directions. Meeting all these wonderful people has also been rewarding on a personal level".