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Consciousness and fMRI - Definition, Study, Research




The purpose of this paper is to discuss consciousness and whether fMRI can be used to identify or prove the presence of what we define as consciousness. Using research in fMRI imagery and research in consciousness the paper will address the following areas of interest: (a) the paper will forward a personal definition of consciousness, (b) the paper will discuss how consciousness is defined in contemporary science, (c) how fMRI methodology reflects the contemporary understanding of consciousness, including strengths and weaknesses, and (d) examples from the literature indicate to what extent we are able to rely on our understanding of fMRI technology and the construct of consciousness to make definitive statements or infer causality. The paper will conclude with a discussion on the philosophical and humane implications with regards to this topic.

FMri Research

Defining Consciousness

Personal Definition. There is no consensus in science regarding the definition of consciousness. It is difficult to define consciousness because if we say it is the quality of being conscious, then we are faced with the fact that all the processes that uphold a person's ability to be conscious, are carried out by the brain on an unconscious level. At the very least, that means consciousness has to be the study of being conscious and how unconscious processes uphold being conscious. But, we still have not defined the word conscious, and that means addressing all the ways a person can be awake or aware. What about a dream in which a person dreams they are awake? In short, consciousness is complex.

However, for the sake of argument, consciousness may be defined as the capability of an entity to respond to the environment. If consciousness is the quality of being conscious, and being conscious refers to some kind of state of awareness or alertness, then probably the closest definition possible is to equate consciousness with the responsiveness of an organism or entity. Based on this personal definition, the task of the paper is now to address whether fMRI methodology can make a contribution to the study of response capabilities of the human brain.

Scientific Definition. Velmans (2009) said "some consciousness researchers have doubted that a systematic study of 'consciousness' as such, is even possible" (p. 142). Sloman (1991) argued that "people who discuss consciousness delude themselves in thinking that they know what they are talking about...it's not just one thing but many things muddled together" (p. 2). Stanovich (1991) complained that consciousness is a "ghost in the machine" - it "fractionates into half a dozen or more different usages," it is a "botched concept" and as a construct it merits the "death penalty" (pp. 696-697). Kelly and Kelly (2007) cites Searle on Freud, saying "what we call consciousness is just a mode of perception of states that are unconscious in their mode of existence" (p. 331). They go on to deliver a comprehensive explanation of how consciousness is a term that divides people. There are those who attach all manner of states of awareness to the term, and there are those who prefer not to use the term at all because of its mystical baggage. In short, it may be argued there is no consensus regarding the definition of consciousness in contemporary science.

fMRI Methodology and Consciousness

The fMRI technology is able to capture "magnetic moments in the brain's activity" and "the MR imaging method most often used to produce information related to brain function is called BOLD (blood oxygenation level dependent) contrast imaging.". The simplest way to qualify what happens in fMRI imaging is that "the subject performs a task in the scanner while BOLD images of the whole brain are collected every 1-3 s. The images show small changes in the brightness levels of certain brain areas (related to blood oxygen concentration changes, which reflect brain activity."

Amaro and Barker (2006) present a copious and detailed overview of fMRI technology. It references over 150 articles, and it contains careful explanations of the technology and research surrounding fMRI. Yet, Amaro and Barker do not even mention the word consciousness, choosing instead to discuss cognition and cognitive processes. This seems to be the main theme of the literature reviewed by Amaro and Barker (2006): it is possible to use fMRI methodology to detect the relation between cognition and cognitive processes in relation to various stimuli in laboratory experiments. In this way, fMRI technology reveals much about the way the brain responds to its environment without often resorting to the term consciousness.

Literature Review

When one begins executing searches to discover literature on fMRI technology that mentions consciousness, the term is only used sparingly, and in a limited context. For example, Eisenberger, Lieberman and Satpute (2005) published an article titled Personality from a controlled processing perspective: An fMRI study of neuroticism, extraversion, and self-consciousness. It is understood here they refer to being aware of oneself. The word self-awareness could be substituted for the word self-consciousness without changing the meaning.

Similarly, McKiernan, D'Angelo, Kaufman and Binder published Interrupting the "stream of consciousness": an fMRI investigation. Here the authors plainly use the term stream of consciousness to refer to transitions in a person's attention as they go from a resting state to a task-induced state - again, nothing explicitly involving the term consciousness. What is typical in the literature is to see the word conscious as contrasted with the word unconscious, and the term consciousness usually refers to the state of being conscious or awake (Boly et al., 2007).

Nani, Blumenfeld and Laureys (2013) go to great lengths to assert that fMRI technology has revolutionized the study of consciousness in their book, Neuroimaging of consciousness. However, they patently adopt consciousness as a term referring to the waking state, and they even equate consciousness with brain "arousal" (p. 3).

Using the term consciousness to refer to the state of being awake, (Boly et al., 2007) measured brain activity associated with verbal and nonverbal functioning and found that more brain activity occurs apart from verbal functioning tan previously assumed. They claim this could one day allow physicians to monitor nonverbal or unconscious patients and detect meaningful brain activity representing wakefulness and awareness. In other words, there may be levels of awareness that occur just prior to verbal activation that is indicative of conscious thought.

Safavi, Kapoor, Logothetis and Panagiotaropoulos (2014) are interested in separating out the reception of information from the subsequent response to a stimulus. They are also interested in separating the conscious from the nonconscious processes, which underlying being conscious or awake. However, they also denote the limitations of existing research using fMRI to study consciousness saying that in order to study "consequences and true correlates of conscious experiences, we need to have an integrative view ... the neural correlates of consciousness must not only entail better-designed experiments but also diverse experimental techniques that could measure brain activity on different spatial and temporal scales" (para. 7). However, without question, it may be said that "fMRI offers a very powerful method to probe brain responses to cognitive tasks" (Amaro & Barker, 2006, p. 229).

Conclusion: Philosophical and Human Implications

There is one other disturbing line of argumentation that is relevant to this paper. Kelly and Kelly (2007) refer to a school of thought existing today among top scientists in the world that holds our conscious waking state and our ability to understand ourselves and our minds, is an illusory quality. There is in fact no ability to know what consciousness is or what the mind is.

At least part of the difficulty in defining consciousness comes from the ambiguity of the term. As such fMRI methodology studies the waking state of the human experience, and human cognitive processes, and attempts to relate these to its non-waking correlates. It is perfectly capable of making much progress studying how cognitive processes relate to external and internal processes using these terms.

The philosophical and human implications are comprised in at least one of the following statements: either (a) humans are not intelligent enough to define consciousness, or (b) humans need to use a term like cognition, instead of consciousness, to operationalize how the brain responds to its environment.

In short, we can use the term consciousness to refer to being awake, but it is more complicated than that. Consider how fMRI technology allows us to chart the relation between waking states of performance on demand, verbal activity, social cognition, and the brain activity that occurs on the nonconscious levels to support the conscious experience of being awake. In other words, consciousness entails more than the study of being awake. It has to entail the study of how being awake merges in a meaningful way with all the other states the human mind is capable of experiencing. The conscious waking state is obviously just the tip of the iceberg regarding what we mean by the capacity to have awareness across many different states of existence. For these reasons, for the time being, consciousness is best operationalized as the brain's performance of cognitive processes.

References

Amaro, E., & Barker, G. J. Study design in fMRI: basic principles. Brain and Cognition, 60(3), 220-232. doi:10.1016/j.bandc.2005.11.009

Boly, M., Coleman, M. R., Davis, M. H., Hampshire, A., Bor, D., Moonen, G., ... & Owen, A. M. (2007). When thoughts become action: an fMRI paradigm to study volitional brain activity in non-communicative brain injured patients. Neuroimage, 36(3), 979-992. doi:10.1016/j.neuroimage.2007.02.047.

Eisenberger, N. I., Lieberman, M. D., & Satpute, A. B. (2005). Personality from a controlled processing perspective: an fMRI study of neuroticism, extraversion, and self-consciousness. Cognitive, Affective, & Behavioral Neuroscience, 5(2), 169-181. Doi 10.3758/CABN.5.2.169.

McKiernan, K. A., D'Angelo, B. R., Kaufman, J. N., & Binder, J. R. (2006). Interrupting the "stream of consciousness": an fMRI investigation. Neuroimage, 29(4), 1185-1191. doi: 10.1016/j.neuroimage.2005.09.030

Safavi, S., Kapoor, V., Logothetis, N. K., & Panagiotaropoulos, T. I. (2015). Is the frontal lobe involved in conscious perception? Beyond the simple contrastive analysis: Appropriate experimental approaches for unraveling the neural basis of conscious experience, 70.

Sloman, A. (1991). Developing concepts of consciousness. Behavioral and Brain Sciences, 14(4), pp. 694-695.

Stanovich, K.E. (1991). Damn! There goes that ghost again! Behavioral and Brain Sciences 14(4), pp. 696-697. DOI:

Velmans, M. (2009). How to define consciousness - And how not to define consciousness. Journal of Consciousness Studies, 16(5), 139-156.