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Consciousness in humans and non-human animals: recent advances and future directions.

Boly M, Seth AK, Wilke M, Ingmundson P, Baars B, Laureys S, Edelman DB, Tsuchiya N - Front Psychol (2013)

Bottom Line: In addition, much progress has been made in the understanding of non-vertebrate cognition relevant to possible conscious states.Finally, major advances have been made in theories of consciousness, and also in their comparison with the available evidence.Along with reviewing these findings, each author suggests future avenues for research in their field of investigation.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, University of Wisconsin Madison, WI, USA ; Department of Psychiatry, Center for Sleep and Consciousness, University of Wisconsin Madison, WI, USA ; Coma Science Group, Cyclotron Research Centre and Neurology Department, University of Liege and CHU Sart Tilman Hospital Liege, Belgium.

ABSTRACT
This joint article reflects the authors' personal views regarding noteworthy advances in the neuroscience of consciousness in the last 10 years, and suggests what we feel may be promising future directions. It is based on a small conference at the Samoset Resort in Rockport, Maine, USA, in July of 2012, organized by the Mind Science Foundation of San Antonio, Texas. Here, we summarize recent advances in our understanding of subjectivity in humans and other animals, including empirical, applied, technical, and conceptual insights. These include the evidence for the importance of fronto-parietal connectivity and of "top-down" processes, both of which enable information to travel across distant cortical areas effectively, as well as numerous dissociations between consciousness and cognitive functions, such as attention, in humans. In addition, we describe the development of mental imagery paradigms, which made it possible to identify covert awareness in non-responsive subjects. Non-human animal consciousness research has also witnessed substantial advances on the specific role of cortical areas and higher order thalamus for consciousness, thanks to important technological enhancements. In addition, much progress has been made in the understanding of non-vertebrate cognition relevant to possible conscious states. Finally, major advances have been made in theories of consciousness, and also in their comparison with the available evidence. Along with reviewing these findings, each author suggests future avenues for research in their field of investigation.

No MeSH data available.


Related in: MedlinePlus

(A) A 2-by-2 factorial design for independent manipulation of top-down attention and conscious visibility of the stimulus (Watanabe et al., 2011). Subjects are asked to carry out one of two attention tasks while viewing either a visible or invisible target stimulus. At the same time, dependent variables, such as hemodynamic responses in the brain, are measured. Here, we illustrate roughly what participants perceived in each condition (not the physical stimulus) in the study by Watanabe and colleagues. Subjects either had to report the presence of a target letter when it appeared or whether they could see the target grating or not. (B) fMRI responses in V1 is strongly modulated by top-down attention but not by conscious visibility of the grating. Modified based on Figures 2, S2 (n = 7 in total) in (Watanabe et al., 2011). The data was provided by the original author. The area under the curve (7–18 s from the block onset) is normalized to the attended and visible condition. The error bar represents 95% confidence interval.
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Figure 4: (A) A 2-by-2 factorial design for independent manipulation of top-down attention and conscious visibility of the stimulus (Watanabe et al., 2011). Subjects are asked to carry out one of two attention tasks while viewing either a visible or invisible target stimulus. At the same time, dependent variables, such as hemodynamic responses in the brain, are measured. Here, we illustrate roughly what participants perceived in each condition (not the physical stimulus) in the study by Watanabe and colleagues. Subjects either had to report the presence of a target letter when it appeared or whether they could see the target grating or not. (B) fMRI responses in V1 is strongly modulated by top-down attention but not by conscious visibility of the grating. Modified based on Figures 2, S2 (n = 7 in total) in (Watanabe et al., 2011). The data was provided by the original author. The area under the curve (7–18 s from the block onset) is normalized to the attended and visible condition. The error bar represents 95% confidence interval.

Mentions: Functional MRI studies typically reveal poor correlation between conscious contents and activity in primary sensory cortical areas (for review see Dehaene and Changeux, 2011). However, the evidence remains mixed. For example, in a bistable perception paradigm (where for the same stimulus, perception alternates between two conscious scenes), activity in primary visual cortex (V1) and lateral geniculate nuclei (LGN) was found to correlate well with conscious perception (Tong, 2003; Haynes and Rees, 2005; Wunderlich et al., 2005). Ongoing discussions concern whether these effects are partially or entirely (Watanabe et al., 2011) confounded by the effects of attention (Boynton, 2011; Watanabe et al., 2011) (Figure 4). It is also possible that BOLD signals measured with fMRI may not reflect the underlying spiking activities in the measured area (Maier et al., 2008) (see NCC studies in non-human primates).


Consciousness in humans and non-human animals: recent advances and future directions.

Boly M, Seth AK, Wilke M, Ingmundson P, Baars B, Laureys S, Edelman DB, Tsuchiya N - Front Psychol (2013)

(A) A 2-by-2 factorial design for independent manipulation of top-down attention and conscious visibility of the stimulus (Watanabe et al., 2011). Subjects are asked to carry out one of two attention tasks while viewing either a visible or invisible target stimulus. At the same time, dependent variables, such as hemodynamic responses in the brain, are measured. Here, we illustrate roughly what participants perceived in each condition (not the physical stimulus) in the study by Watanabe and colleagues. Subjects either had to report the presence of a target letter when it appeared or whether they could see the target grating or not. (B) fMRI responses in V1 is strongly modulated by top-down attention but not by conscious visibility of the grating. Modified based on Figures 2, S2 (n = 7 in total) in (Watanabe et al., 2011). The data was provided by the original author. The area under the curve (7–18 s from the block onset) is normalized to the attended and visible condition. The error bar represents 95% confidence interval.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3814086&req=5

Figure 4: (A) A 2-by-2 factorial design for independent manipulation of top-down attention and conscious visibility of the stimulus (Watanabe et al., 2011). Subjects are asked to carry out one of two attention tasks while viewing either a visible or invisible target stimulus. At the same time, dependent variables, such as hemodynamic responses in the brain, are measured. Here, we illustrate roughly what participants perceived in each condition (not the physical stimulus) in the study by Watanabe and colleagues. Subjects either had to report the presence of a target letter when it appeared or whether they could see the target grating or not. (B) fMRI responses in V1 is strongly modulated by top-down attention but not by conscious visibility of the grating. Modified based on Figures 2, S2 (n = 7 in total) in (Watanabe et al., 2011). The data was provided by the original author. The area under the curve (7–18 s from the block onset) is normalized to the attended and visible condition. The error bar represents 95% confidence interval.
Mentions: Functional MRI studies typically reveal poor correlation between conscious contents and activity in primary sensory cortical areas (for review see Dehaene and Changeux, 2011). However, the evidence remains mixed. For example, in a bistable perception paradigm (where for the same stimulus, perception alternates between two conscious scenes), activity in primary visual cortex (V1) and lateral geniculate nuclei (LGN) was found to correlate well with conscious perception (Tong, 2003; Haynes and Rees, 2005; Wunderlich et al., 2005). Ongoing discussions concern whether these effects are partially or entirely (Watanabe et al., 2011) confounded by the effects of attention (Boynton, 2011; Watanabe et al., 2011) (Figure 4). It is also possible that BOLD signals measured with fMRI may not reflect the underlying spiking activities in the measured area (Maier et al., 2008) (see NCC studies in non-human primates).

Bottom Line: In addition, much progress has been made in the understanding of non-vertebrate cognition relevant to possible conscious states.Finally, major advances have been made in theories of consciousness, and also in their comparison with the available evidence.Along with reviewing these findings, each author suggests future avenues for research in their field of investigation.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, University of Wisconsin Madison, WI, USA ; Department of Psychiatry, Center for Sleep and Consciousness, University of Wisconsin Madison, WI, USA ; Coma Science Group, Cyclotron Research Centre and Neurology Department, University of Liege and CHU Sart Tilman Hospital Liege, Belgium.

ABSTRACT
This joint article reflects the authors' personal views regarding noteworthy advances in the neuroscience of consciousness in the last 10 years, and suggests what we feel may be promising future directions. It is based on a small conference at the Samoset Resort in Rockport, Maine, USA, in July of 2012, organized by the Mind Science Foundation of San Antonio, Texas. Here, we summarize recent advances in our understanding of subjectivity in humans and other animals, including empirical, applied, technical, and conceptual insights. These include the evidence for the importance of fronto-parietal connectivity and of "top-down" processes, both of which enable information to travel across distant cortical areas effectively, as well as numerous dissociations between consciousness and cognitive functions, such as attention, in humans. In addition, we describe the development of mental imagery paradigms, which made it possible to identify covert awareness in non-responsive subjects. Non-human animal consciousness research has also witnessed substantial advances on the specific role of cortical areas and higher order thalamus for consciousness, thanks to important technological enhancements. In addition, much progress has been made in the understanding of non-vertebrate cognition relevant to possible conscious states. Finally, major advances have been made in theories of consciousness, and also in their comparison with the available evidence. Along with reviewing these findings, each author suggests future avenues for research in their field of investigation.

No MeSH data available.


Related in: MedlinePlus