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David Henderson

Abstract

Naturalized epistemology is not a recent invention, nor is it a philosophical invention. Rather, it is a cognitive phenomena that is pervasive and desirable in the way of human epistemic engagement with their world. It is a matter of the way that one’s cognitive processes can be modulated by information gotten from those same or wider cognitive processes. Such modulational control enhances the reliability of one’s cognitive processes in many ways – and judgments about objective epistemic justification consistently evince a reasonable demand for it. However, with suitable modulational control in place within an agent or a community of agents, the fitting cognitive processes take time to generate information that then engenders changes in processes and norms. Further, as there are significant historical and biographical contingencies involving trajectories through one’s environment, there are contingencies in the information and modifications that will be engendered by suitable modulational control. As a result, what makes for objectively justified belief at a time will vary – as the fruits of suitable modulational control accrue over time. This is a moderate form of historicism about epistemic justification.

David Henderson

Abstract

This paper explores the role and limits of cognitive simulation in understanding or explaining others. In simulation, one puts one’s own cognitive processes to work on pretend input similar to that one supposes that the other plausibly had. Such a process is highly useful. However, it is also limited in important ways. Several limitations fall out from the various forms of cognitive diversity. Some of this diversity results from cultural differences, or from differences in individuals’ cognitive biographies. Such diversity is clearly important in history. Some sorts of such diversity are discussed, with attention to the results of contemporary cognitive science. It is argued that one must sometimes employ mixed (simulation-based/theory-based) strategies, and that sometimes what is done will be neither purely simulation nor purely theory-based.

David Henderson, Terence Horgan, Matjaž Potrč and Hannah Tierney

The authors argue in favor of the “nonconciliation” (or “steadfast”) position concerning the problem of peer disagreement. Throughout the paper they place heavy emphasis on matters of phenomenology—on how things seem epistemically with respect to the net import of one’s available evidence vis-à-vis the disputed claim p, and on how such phenomenology is affected by the awareness that an interlocutor whom one initially regards as an epistemic peer disagrees with oneself about p. Central to the argument is a nested goal/sub-goal hierarchy that the authors claim is inherent to the structure of epistemically responsible belief-formation: pursuing true beliefs by pursuing beliefs that are objectively likely given one’s total available evidence; pursuing this sub-goal by pursuing beliefs that are likely true (given that evidence) relative to one’s own deep epistemic sensibility; and pursuing this sub-sub-goal by forming beliefs in accordance with one’s own all-in, ultima facie, epistemic seemings.

Tamar R. Makin, Jan Scholz, Nicola Filippini, David Henderson Slater, Irene Tracey and Heidi Johansen-Berg

Phantom pain has become an influential example of maladaptive cortical plasticity. According to this model, sensory deprivation following limb amputation allows for intra-regional invasion of neighbouring cortical representations into the former hand area of the primary sensorimotor cortex, which gives rise to pain sensations. Over the years, this model was extended to explain other disorders of pain, motor control and tinnitus, and has inspired rehabilitation strategies. Yet, other research, demonstrating that phantom hand representation is maintained in the sensorimotor system, and that phantom pain can be triggered by bottom-up aberrant inputs, may call this model to question. Using fMRI, we identified the cortical area representing the missing hand in a group of 18 arm amputees. This allowed us to directly study changes in the ‘phantom’ cortex associated with chronic phantom pain, using functional connectivity and voxel-based morphometry. We show that, while loss of sensory input is generally characterized by structural degeneration of the deprived sensorimotor cortex, the experience of persistent pain was associated with preserved intra-regional structure and functional organization. Furthermore, consistent with the dissociative nature of phantom sensations from other sensory experiences, phantom pain is also associated with reduced long-range inter-regional functional connectivity. We propose that this disrupted inter-regional connectivity may be consequential, rather than causal, of the retained yet isolated local representation of phantom pain. We therefore propose that, contrary to the maladaptive model, cortical plasticity occurs when powerful and long-lasting subjective sensory experience, most likely due to peripheral inputs, is decoupled from the external sensory environment.

Eugene Duff, Heidi Johansen-Berg, Jan Scholz, Tamar Makin, David Henderson Slatere, Nicola Filippini and Irene Tracey