Papers by Joshua Fost
Building Lesson Plans for Twenty-First-Century Active Learning
A New Look at General Education
A New Team-Teaching Approach to Structured Learning
Fully Active Learning
We offer a working definition of active learning in which learning is active to the extent that i... more We offer a working definition of active learning in which learning is active to the extent that it engages the cognitive processes known to be involved in comprehension, reasoning, memory, and pattern perception; it is not the same as student-centered or collaborative learning. To maximize students' opportunities for active learning, we use a variety of pedagogical techniques and technological supports. Pedagogically, we often use "engagement prompts," which are questions or challenges for all students to consider for the duration of an activity, even when they are not contributing. We also use collaborative learning in small groups; short, summative reflection essays; and fast-paced relay-style activities that require students to attend very carefully to the substance of their classmates' contributions. Technologically, we record the amount of time each student speaks to ensure that we call on all students approximately equally, and we use a tagging system to track the technique used in every activity so that later programmatic assessment will be more robust.
The Review of Philosophy and Psychology, Dec 2014
A common reaction to functional diversity is to group entities into clusters that are functionall... more A common reaction to functional diversity is to group entities into clusters that are functionally similar. I argue here that people are diverse with respect to reasoning-related processes, and that these processes satisfy the basic requirements for evolving entities: they are heritable, mutable, and subject to selective pressures. I propose a metric to quantify functional difference and show how this can be used to place psychological processes into a structure akin to a phylogenetic or evolutionary tree. Three species concepts are repurposed from biology and used to understand relationships in that tree.
Embodied Aesthetics: Proceedings of the 1st International Conference on Aesthetics and the Embodied Mind, 26th-28th August 2013, Oct 14, 2014
I propose a neuropsychological and evolutionary hypothesis for the origin of hedonic response to ... more I propose a neuropsychological and evolutionary hypothesis for the origin of hedonic response to the beautiful. The hypothesis aims to explain well-known aesthetic effects, such as mere exposure, prototypicality, and fluency, while remaining neutral with respect to sensory modality and subject matter. Three lines of evidence are used to build the case. First, the phenomenology of some drugs (e.g. psilocybin, MDMA) includes an aesthetic component, suggesting that their neurochemistry, which tends to focus on serotonin and the 5-HT2A receptor, may be involved in normal aesthetic function. Second, some neuropsychiatric disorders (e.g. obsessive-compulsive disorder and autism spectrum) include psychological pressures toward strongly patterned stimuli and behaviors, i.e. an aesthetic-like demand for “just-rightness.” Third, evidence from the cortical binding literature suggest that gamma and theta-band oscillations increase when percepts are coherent and familiar. The hypothesis is that serotonin modulates the gain curve between cortical oscillations and neural reward systems; OCD and autism attenuate this, requiring more perceptual coherence for a fixed level of reward, while hallucinogens and MDMA augment it, producing exaggerated reward and spurious perceptual coherence. The proposed neural circuit is evolutionarily advantageous because it encourages animals to gather the information necessary to parse their perceptions, categorize them, and spend more time in familiar, understandable circumstances. Normal aesthetic behavior commandeers this circuit and sees agents who spontaneously organize their perceptual world. Doing so increases cortical gamma and theta oscillations and results in hedonic response.
Innovative Higher Education, Mar 23, 2012
In this article I describe software that facilitates “question-centric curricula” in which big qu... more In this article I describe software that facilitates “question-centric curricula” in which big questions, rather than academic disciplines, are the primary means of organizing educational resources. To find these questions, the software scans course catalogs and extracts all sentences ending in a question mark. To find connections between questions and courses, I present several computational techniques. One leverages the Library of Congress system; another implements so-called semantic technology that uses huge numbers of simple internet searches to ascertain the meaning of texts. The software assembles the results and shows, in one image, how every course at an institution relates to a given question.
Linguistic and Philosophical Investigations, May 2013
Personal indexicals are often taken to refer to the agent of an expression’s context, but deviant... more Personal indexicals are often taken to refer to the agent of an expression’s context, but deviant uses (e.g. ‘I’m parked out back’) complicate matters. I argue that personal indexicals refer to the extended self of the agent, where the extended self is a mereological chimera incorporating whatever determines our behavioral capacities. To ascertain the persistence conditions of personal identity, I propose a method for selecting a level of description and a set of functional properties at that level that remain constant over a lifetime. I argue for functional constancy, and against continuity, as the central determinant of diachronic identity.
Proceedings of the 1st International Conference on Philosophy: Yesterday, Today, and Tomorrow (PYTT 2013), Dec 2013
Contrary to intuitions that human beings are free to think and act with “buck-stopping” freedom, ... more Contrary to intuitions that human beings are free to think and act with “buck-stopping” freedom, philosophers since Holbach and Hume have argued that universal causation makes free will nonsensical. Contemporary neuroscience has strengthened their case and begun to reveal subtle and counterintuitive mechanisms in the processes of conscious agency. Although some fear that determinism undermines moral responsibility, the opposite is true: free will, if it existed, would undermine coherent systems of justice. Moreover, deterministic views of human choice clarify the conditions in which we ought to protect people from themselves, for example when they cannot give informed consent to medical procedures. Some of the most unresolved questions in this domain are just now emerging; they include robot ethics and the responsibilities of groups. We propose a philosophical and scientific research program to apply complex systems science to these problems.
The Neuroscientist, Jan 1, 1999
Natural selection favors animals that make successful predictive theories about the world. The fi... more Natural selection favors animals that make successful predictive theories about the world. The first step in the formation of these theories is the construction of complex, multi-feature percepts. This process requires resolution of the binding problem, possibly via rhythmic cortical oscillations as suggested by von der Malsburg, Singer, Koch & Crick, and others. If the binding process were made rewarding, animals might enjoy theory-making and spontaneously become "smarter." I argue that the serotonergic raphe may have been used by evolution to link cortical binding with limbic reward centers and so serve as a neural substrate for the enjoyment of successful theory-making. I present evidence from the study of disorders like OCD and autism and drugs like LSD and MDMA suggesting that rhythmicity, reward, and pattern recognition are causally linked. I also propose that the genus Homo has tied powerful symbol manipulation hardware ("language") to the binding/theory-making circuits, allowing the construction, rehearsal, and communication of sophisticated models of the world. I suggest that many interesting phenomena, such as music-induced euphoria, deja vu, and the so-called "temporal lobe personality" can be explained by the interactions between these systems.
Free Inquiry, 2005
In many debates, the sides taken are science vs. religion; this strikes me as slightly misleading... more In many debates, the sides taken are science vs. religion; this strikes me as slightly misleading, and slightly risky. A better distinction, I contend, is between dogma and skepticism, and I want to make the case that in most discussion, making the distinction is worthwhile.
If Not God, Then What?: Neuroscience, Aesthetics, and the Origins of the Transcendent
In If Not God, Then What? theoretical neuroscientist Joshua Fost shows how the search for beauty ... more In If Not God, Then What? theoretical neuroscientist Joshua Fost shows how the search for beauty is the source of both religious experience and scientific theorizing. The pleasure of seeing a beautiful face, the thrill of understanding a new idea, the sublimity of art and the power of religious transformation are all, in the end, the result of a brain that wants to make sense of the world. Weaving ideas from brain science and everyday activities — from Sunday cartoons to existentialism — Fost shows how a biological idiosyncrasy motivates them all. But if religious experience is just a special activity pattern in neurons, what should we think about its undeniable and emotionally transformative power? If everything we do is determined by physics, what is the basis for free will, or ethics? Blending receptivity to the glory of spiritual exultation with an insistence on naturalistic foundations, If Not God, Then What? breaks new ground and gives its readers insight into a compelling new worldview.
The Journal of …, Jan 1, 1997
Cortical synapses exhibit several forms of short-term plasticity, but the contribution of this pl... more Cortical synapses exhibit several forms of short-term plasticity, but the contribution of this plasticity to visual response dynamics is unknown. In part, this is because the simple patterns of stimulation used to probe plasticity in vitro do not correspond to patterns of activity that occur in vivo. We have developed a method of quantitatively characterizing short-term plasticity at cortical synapses that permits prediction of responses to arbitrary patterns of stimulation. Synaptic responses were recorded intracellularly as EPSCs and extracellularly as local field potentials in layer 2/3 of rat primary visual cortical slices during stimulation of layer 4 with trains of electrical stimuli containing random mixtures of frequencies. Responses exhibited complex dynamics that were well described by a simple threecomponent model consisting of facilitation and two forms of depression, a stronger form that decayed exponentially with a time constant of several hundred milliseconds and a weaker, but more persistent, form that decayed with a time constant of several seconds. Parameters obtained from fits to one train were used to predict accurately responses to other random and constant frequency trains. Control experiments revealed that depression was not caused by a decrease in the effectiveness of extracellular stimulation or by a buildup of inhibition. Pharmacological manipulations of transmitter release and postsynaptic sensitivity suggested that both forms of depression are mediated presynaptically. These results indicate that firing evoked by visual stimuli is likely to cause significant depression at cortical synapses. Hence synaptic depression may be an important determinant of the temporal features of visual cortical responses.
The Journal of Computational Neuroscience, Jan 1, 1996
We developed a multicompartmental Hodgkin-Huxley model of the Hermissenda type-B photoreceptor an... more We developed a multicompartmental Hodgkin-Huxley model of the Hermissenda type-B photoreceptor and used it to address the relative contributions of reductions of two K+ currents, IA and IC, to changes in cellular excitability and synaptic strength that occur in these cells after associative learning. We found that reductions of gC, the peak conductance of IC, substantially increased the firing frequency of the type-B cell during the plateau phase of a simulated light response, whereas reductions of gA had only a modest contribution to the plateau frequency. This can be understood at least in part by the contributions of these currents to the light-induced (nonspiking) generator potential, the plateau of which was enhanced by gC reductions, but not by gA reductions. In contrast, however, reductions of gA broadened the type-B cell action potential, increased Ca2+ influx, and increased the size of the postsynaptic potential produced in a type-A cell, whereas similar reductions of gC had only negligible contributions to these measures. These results suggest that reductions of IA and IC play important but different roles in type-B cell plasticity.
The Journal of Computational Neuroscience, Jan 1, 1996
Because the Hermissenda eye is relatively simple and its cells well characterized, it provides an... more Because the Hermissenda eye is relatively simple and its cells well characterized, it provides an attractive preparation for detailed computational analysis. To examine the neural mechanisms of learning in this system, we developed multicompartmental models of the type-A and type-B photoreceptors, simulated the eye, and asked three questions: First, how do conductance changes affect cells in a network as compared with those in isolation; second, what are the relative contributions of increases in B-cell excitability and synaptic strength to network output; and third, how do these contributions vary as a function of network architecture? We found that reductions in the type-B cells of two K+ currents, I A and I C, differentially affected the type-B cells themselves, with I C reductions increasing firing rate (excitability) in response to light, and I A reductions increasing quantal output (synaptic strength) onto postsynaptic targets. Increases in either type-B cell excitability or synaptic strength, induced directly or indirectly, each suppressed A-cell photoresponses, and the combined effect of both changes occurring together was greater than either alone. To examine the effects of network architecture, we compared the full network with a simple feedforward B-A pair and intermediate configurations. Compared with a feedforward pair, the complete network exhibited greater A-cell sensitivity to B-cell changes. This was due to many factors, including an increased number of B-cells (which increased B-cell impact on A-cells), A-B feedback inhibition (which slowed both cell types and altered spike timing relationships), and B-B lateral inhibition (which reduced B-cell sensitivity to intrinsic biophysical modifications). These results suggest that an emergent property of the network is an increase both in the rate of information acquisition (“learning”) and in the amount of information that can be stored (“memory”).
Computational and physiological analysis of neural plasticity in Hermissenda: from potassium currents to network architecture
Leonardo, Jan 1, 2004
A realization of Hesse's Glass Bead Game is presented. By associating small images ("beads" and "... more A realization of Hesse's Glass Bead Game is presented. By associating small images ("beads" and "tiles") with ideas described in ordinary prose, a new vocabulary of glyphs is developed; these glyphs are later assembled in special ways, such that their spatial arrangement asserts symbolic relationships between the corresponding ideas. In particular, arrangements take the form bead-tile-bead, signifying subject-predicate-object assertions. Arranging and connecting multiple bead phrases on a two-dimensional grid allows large groups of related assertions to be made in a compact and appealing visual space, and the communication of rich symbolic connectivity less lengthy and cumbersome than it would be with prose. The entire structure, including narrative, bead phrases, and imagery is represented in the technical forms of the Semantic Web; all beads and tiles are labeled with URIs, and bead phrases become reified RDF.
Conference Presentations by Joshua Fost
“Remaking Responsibility: Complexity and Scattered Causes in Human Agency” (co-authored with Joshua Fost)
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Papers by Joshua Fost
Conference Presentations by Joshua Fost