Columbia University
Department of Philosophy
PhD, 2018
Baltimore, Maryland, United States of America
  •  316
    The Neural Substrates of Conscious Perception without Performance Confounds
    with Brian Odegaard and Brian Maniscalco
    In Felipe De Brigard & Walter Sinnott-Armstrong (eds.), Anthology of Neuroscience and Philosophy, . forthcoming.
    To find the neural substrates of consciousness, researchers compare subjects’ neural activity when they are aware of stimuli against neural activity when they are not aware. Ideally, to guarantee that the neural substrates of consciousness—and nothing but the neural substrates of consciousness—are isolated, the only difference between these two contrast conditions should be conscious awareness. Nevertheless, in practice, it is quite challenging to eliminate confounds and irrelevant differences b…Read more
  •  914
    Whether the prefrontal cortex is part of the neural substrates of consciousness is currently debated. Against prefrontal theories of consciousness, many have argued that neural activity in the prefrontal cortex does not correlate with consciousness but with subjective reports. We defend prefrontal theories of consciousness against this argument. We surmise that the requirement for reports is not a satisfying explanation of the difference in neural activity between conscious and unconscious trial…Read more
  •  32
    Domain-general and Domain-specific Patterns of Activity Support Metacognition in Human Prefrontal Cortex
    with Hakwan Lau and Stephen M. Fleming
    The Journal of Neuroscience 38 (14): 3534-3546. 2018.
    Metacognition is the capacity to evaluate the success of one's own cognitive processes in various domains; for example, memory and perception. It remains controversial whether metacognition relies on a domain-general resource that is applied to different tasks or if self-evaluative processes are domain specific. Here, we investigated this issue directly by examining the neural substrates engaged when metacognitive judgments were made by human participants of both sexes during perceptual and memo…Read more
  •  135
    Measuring away an attentional confound?
    with Yasha Mouradi, Claire Sergent, Ned Block, Vincent Taschereau-Dumouchel, David Rosenthal, Piercesare Grimaldi, and Hakwan Lau
    Neuroscience of Consciousness 3 (1): 1-3. 2017.
    A recent fMRI study by Webb et al. (Cortical networks involved in visual awareness independent of visual attention, Proc Natl Acad Sci U S A 2016;113:13923–28) proposes a new method for finding the neural correlates of awareness by matching atten- tion across awareness conditions. The experimental design, however, seems at odds with known features of attention. We highlight logical and methodological points that are critical when trying to disentangle attention and awareness.
  •  1351
    The Neural Correlates of Consciousness
    with Hakwan Lau
    In Uriah Kriegel (ed.), The Oxford Handbook of the Philosophy of Consciousness, Oxford University Press. forthcoming.
    In this chapter, we discuss a selection of current views of the neural correlates of consciousness (NCC). We focus on the different predictions they make, in particular with respect to the role of prefrontal cortex (PFC) during visual experiences, which is an area of critical interest and some source of contention. Our discussion of these views focuses on the level of functional anatomy, rather than at the neuronal circuitry level. We take this approach because we currently understand more about…Read more
  •  55
    Razonamiento Animal: Negación y Representaciones de Ausencia
    Revista Argentina de Ciencias Del Comportamiento 3 (1): 20-33. 2011.
    In this paper, I reject that animal reasoning, negation in particular, necessarily involves the representation of absences, as suggested by Bermúdez (2003, 2006, 2007), since this would still work as a logical negation (unavailable for non-linguistic creatures). False belief, pretense, and communication experiments show that non-human animals (at least some primates) have difficulties representing absent entities or properties. I offer an alternative account resorting to the sub-symbolic similar…Read more
  •  238
    Controlling for performance capacity confounds in neuroimaging studies of conscious awareness
    with Jeffrey Chiang and Hakwan Lau
    Neuroscience of Consciousness 1 1-11. 2015.
    Studying the neural correlates of conscious awareness depends on a reliable comparison between activations associated with awareness and unawareness. One particularly difficult confound to remove is task performance capacity, i.e. the difference in performance between the conditions of interest. While ideally task performance capacity should be matched across different conditions, this is difficult to achieve experimentally. However, differences in performance could theoretically be corrected fo…Read more
  •  222
    Low attention impairs optimal incorporation of prior knowledge in perceptual decisions
    with Guillermo Solovey, Brian Maniscalco, Dobromir Rahnev, Floris P. de Lange, and Hakwan Lau
    Attention, Perception, and Psychophysics 77 (6): 2021-2036. 2015.
    When visual attention is directed away from a stimulus, neural processing is weak and strength and precision of sensory data decreases. From a computational perspective, in such situations observers should give more weight to prior expectations in order to behave optimally during a discrimination task. Here we test a signal detection theoretic model that counter-intuitively predicts subjects will do just the opposite in a discrimination task with two stimuli, one attended and one unattended: whe…Read more