Question: “Can science account for consciousness?”
I don’t think everyone currently agrees on the answer, but personally, I believe it can. The future will tell.
Question: “I'm just interested what the scientific explanation is if there is one?”
You’re asking for the scientific explanation; I think I can give some. The followings are current scientific account of consciousness that I know of:
1. What causes or creates consciousness?
The scientific answer is that it is some group of neural circuits. Current evidence shows that the Default Mode Network (1), which includes cingulate cortex, precuneus, medial prefrontal cortex, and other associated areas, is the network of the consciousness neural process when the mind is not concentrating on any specific task. This network overlaps with the network of Global Workspace theory (2) and that of Global Neuronal Workspace theory (3), which include the cortico-thalamic (C-T) core and a network of neurons with long-range axons densely distributed in the prefrontal, fronto-parietal, parieto-temporal, and cingulate cortices. These latter two networks are found to be the consciousness neural process network when the mind is in the mode of attending to a certain stimulus. So, the complete neural network of consciousness is likely to be some form of a combination of the former networks and the latter networks, such as that proposed by Song (4).
It is presently irrefutable that consciousness is caused by the function of this network. Consciousness cannot occur without the function of this network, and anything that affects the function of this network affects the consciousness accordingly. That is why one cannot maintain his/her normal consciousness when this network is affected by injury, diseases (encephalitis, tumor, increased intracranial pressure, etc.), metabolic disturbances (hypoglycemia, hypoxemia, hyponatremia, etc.), pharmacologic effects (sedatives, psychedelics, stimulants, etc.), electrical shock, etc.
2. How can a group of neural circuits, which are material things, give rise to consciousness, which is an immaterial thing?
This question is more difficult to answer scientifically, yet currently there are many theories regarding this issue. For example, some propose that the reentrant neural activity in the thalamocortical system gives rise to conscious experience (4,5). Although, from experimental evidence, the reentrant neural activities seem to be necessary for consciousness to occur, no one can answer why and how consciousness (a non-material entity) should arise from such material activities, all the same. Other theories involve integrated information, electromagnetic field, attention, and adaptation of the brain (7-12), and many of them seem to have the same problem, which in philosophy is known as the hard problem of consciousness (13).
However, currently, there is a way to answer this problem, but the issue is too complex and lengthy to put it here. Briefly, it’s like this: when you see someone nods his/her head, you understand that he/she means yes. So, in principle, an abstract, non-material entity (the non-material information “yes”) can occur from the material activity (the physical nodding). Similarly, in the nervous system, non-material information can occur from material neural signaling. For example, when a certain neural circuit signals the information of a red color, other neural circuits, after reading this signal, acknowledge the red color, and there is the information of the red color in the neural circuit. Yet, this is not what the color red occurs in our mind; it’s just the information of the red color in our mind, like the information of the red color in a computer. Now, when a certain neural circuit signals the information of a conscious awareness of a red color, other neural circuits, after reading this specific signal, naturally acknowledge the conscious awareness of a red color, and the conscious awareness of a red color inevitably occurs in the neural circuits. That is how the non-material conscious awareness of the red color (the red color as it appears in our mind) occurs in our material brains. (See here and here for more detailed discussions).
3. Why is there consciousness?
You can note that we don’t have consciousness of every mental activities in our mind, some are sub- or unconscious mental activities. Consciousness occurs in only the final-stage external sensory perceptions and in the highest cognitive-executive functions. That’s why we’re not conscious of early-stage sensory perceptions (e.g., we don’t know what the visual signals that arrive at the primary visual area are like) and why we’re not conscious of cerebellar, basal ganglia, brainstem, and autonomic system activities (e.g., we don’t know what it’s like to coordinate contractions of millions of individual muscle fibers accurately, to contract our pupils, to secrete sweat or hormones, etc.). This is consistently true for billions of humans nowadays and in the past. So, consciousness does not scatter or occur anywhere arbitrarily in the brain – it selectively occurs in only the latest-evolved parts of the brain. This indicates that consciousness is an evolved function, not arbitrarily occurring function.
Now, does consciousness have effects?
Because you’re conscious of your consciousness, the consciousness neural process must function to acknowledge the occurrence of consciousness (otherwise, you cannot be conscious of your consciousness). This means consciousness has physical effects because it affects a physical process (the consciousness neural process) to function to acknowledge it. What is (are) the result(s) of this effect other than acknowledging the consciousness itself? We don’t know for certain now what it is or what they are. But to add another function requires resources to build, to maintain, and to operate it, if the overall effects are not beneficial, the species that have consciousness should become extinct in competition with other species that don’t have consciousness. But, nowadays, human beings and other beings that seem to have consciousness (e.g., mammals and birds) seem to thriving and dominating. So, it indicates that consciousness must have overall beneficial effects that help increase the chance of survival of the species that have it.
Overall, it can be concluded scientifically that consciousness is an evolved function to help increase the chance of survival. And that is why there is consciousness. (Again please read here for more detailed discussions.)
The above answers may not be completely correct yet. But we have come this far only after several decades of serious scientific studies of consciousness. So, I’m confident that finally science can account for consciousness.
Buckner RL, Andrews-Hanna JR, Schacter DL. The brain's default network: anatomy, function, and relevance to disease. Ann N Y Acad Sci. 2008 Mar;1124:1-38. DOI: 10.1196/annals.1440.011.
Baars BJ, Franklin S, Ramsoy TZ. Global workspace dynamics: Cortical “Binding and propagation” enables conscious contents. Front Psychol. 2013;4:200. DOI: 10.3389/fpsyg.2013.00200 PMCID: PMC3664777.
Dehaene S, Naccache L. Towards a cognitive neuroscience of consciousness: Basic evidence and a workspace framework. Cognition. 2001 Apr;79(1-2):1-37.
Song X, Tang X. An extended theory of global workspace of consciousness. Progress in Natural Science. 2008 Jul;18(7):789–793. DOI: https://doi.org/10.1016/j.pnsc.2008.02.003.
Edelman GM, Gally JA, Baars BJ. Biology of Consciousness. Front Psychol. 2011;2:4. DOI: 10.3389/fpsyg.2011.00004 PMCID: PMC3111444.
Llinás R, Ribary U, Contreras D, Pedroarena C. The neuronal basis for consciousness. Philos Trans R Soc Lond B Biol Sci. 1998 Nov;353(1377):1841–1849. DOI: 10.1098/rstb.1998.0336 PMCID: PMC1692417.
Tononi G. An information integration theory of consciousness. BMC Neurosci 2004,5:42. DOI: 10.1186/1471-2202-5-42
McFadden J. The CEMI Field Theory gestalt information and the meaning of meaning. J Conscious Stud. 2013;20 (3-4):3-4.
Ukachoke C. The Basic Theory of the Mind. Charansanitwong Printing Co, 2018. Bangkok, Thailand.
Graziano MSA,Webb TW. The attention schema theory: A mechanistic account of subjective awareness. Front Psychol. 2015;6:500. DOI: 10.3389/fpsyg.2015.00500 PMCID: PMC4407481.
Grossberg S. Adaptive Resonance Theory: how a brain learns to consciously attend, learn, and recognize a changing world. Neural Netw. 2013 Jan;37:1-47. DOI: 10.1016/j.neunet.2012.09.017.
Block N. Comparing the major theories of consciousness. In: Gazzaniga MS, editor. The Cognitive Neurosciences (Chap 77). 4th ed., Cambridge, MA: MIT Press; 2009:1111–1122.
Chalmers DJ. Facing up to the problem of consciousness. J Conscious Stud. 1995;2(3):200-219.