Lawrence Barsalou receives a position in the ARC Accelerator Programme to develop and commercialise the Situated Assessment Method

January 2021

The ARC Accelerator Programme is a first-of-its-kind opportunity designed specifically to help social science researchers to develop ideas based on their research into businesses or ventures that help people, society and the economy.  In the 2021 programme, 15 UK-wide training positions were available across participating universities.

The ARC Accelerator is a six-month programme in which trainees benefit from:  (1) support for exploring and developing their idea, (2) a three-week entrepreneurial bootcamp led by industry experts, (3) specialised sector-specific training with access to experts, investors, and key networks, (4) mentorship to validate ideas, develop business models, and support pitches for funding and investment.

While participating in the ARC programmer, I aim to develop, implement, and distribute the Situated Assessment Method (SAM2) for measuring, predicting, and changing health behaviours, including stress, social connectiveness, eating habits, trichotillomania, etc.  This novel and powerful approach has significant potential for being implemented in digital health apps for use by clinicians, health practitioners, and private individuals.

New PhD position available: Improving engagement with mobile health apps by understanding (mis)alignment between design elements and personal characteristics

January 2021

Aleksandar Matic (Koa Health) and Lawrence Barsalou (University of Glasgow) are supervising this PhD project in the University of Glasgow Center for Doctoral Training in Socially Intelligent Artificial Agents.  Applications are open for the position that begins in Fall 2021, beginning with a year of funded masters work, followed by three years of funded PhD work.

Project summary:  A growing consensus has concluded that improving engagement with health apps requires personalisation at an individual level.  In this project, we will pursue two novel approaches for improving engagement with health apps.

First, we will conduct a retrospective exploration of previous app use as documented in the literature. Specifically, we will assess( a) personal characteristics of individuals who have previously used mobile health apps, (b) design elements (including intervention mechanisms) of these apps, and (c) outcomes related to app engagement (e.g., drop-out rates, frequency of use). Of focal interest will be how personal characteristics and app design interact to produce different levels of app engagement.  We aim to publish a major review of the literature based on this work.

Second, in a well-established stress app that we continue to develop, we will allow users to configure its design features in various ways.  We will also collect data about users’ personal characteristics.  From these data, we hope to develop design principles for tailoring future apps and intervention mechanisms to specific individuals.  A series of studies will be performed in this line of work, together with related publications.

This project is likely to focus on stress as the primary-use case.  In a related project, we are developing and evaluating stress apps that measure and predict stress in specific situations, linking psychological assessment to physiological data harvested implicitly from wearables.  In a third project, we are implementing behaviour change interventions in digital health apps to reduce distress and increase eustress.  Work from all three projects will be integrated to develop maximally effective stress apps, tailored to individuals, that effectively measure, predict, and alter stress experience.

Application sites:

New PhD position available: Developing and assessing a digital health app that implements the Situated Assessment Method to decrease distress and increase eustress

November 2021

Lawrence Barsalou and Esther Papies (University of Glasgow) and Aleksandar Matic (Koa Health) have been awarded a PhD position from the Scottish Graduate School of Social Science beginning in the fall of 2021.  This studentship is associated with SGSSS program that fosters collaborative projects between academia and industry. 

In this project, our team will build and evaluate a health app to help individuals learn about and regulate life stress (utilizing the Situated Assessment Method developed at Glasgow, together with other tools developed at Koa Health).  Of particular interest is building an effective digital tool that promotes learning about distress and eustress to decrease distress and increase eustress (shifting the affect associated with stress from negative to positive). 

The PhD student will become part of a large lab group at the University of Glasgow that focuses on health cognition and behaviour.  The two Glasgow supervisors (Barsalou and Papies) will provide training in health cognition, behaviour change, and research methods.  The industry partner (Matic) will serve as an equal third supervisor, providing training in app development, implementation, and assessment.  The PhD project will play a foundational role for developing future collaborative projects that aim to develop increasingly powerful apps for decreasing distress and increasing eustress.  Students without a masters degree are eligible and will be funded for an additional year of masters training.

Applications open:  1 March 2021.

Lawrence Barsalou, Christoph Scheepers, and Aleksandar Matic win an award from the University of Glasgow Knowledge Exchange Fund for developing a stress app that implements the Situated Assessment Method

December 2020

This award University of Glasgow Knowledge Exchange Fund allows us to collect data that will inform the design of various stress apps currently under development.

Title:  Developing a digital health app that implements the Situated Assessment Method to decrease distress and increase eustress

Summary:  We are developing an academia-industry collaboration for building a digital health app that implements the SAM2 assessment procedure, together with other stress tools that Koa Health has developed.  The central aim of this collaborative work is to decrease distress and increase eustress by (1) inducing users to learn about psychological mechanisms associated with their individual stress, (2) providing users with precision feedback about these stress mechanisms, along with tools for working on them.

Academic contributions will focus on psychological and biological mechanisms of stress.  Industry contributions will focus on electronic hardware and machine learning algorithms for implementing state-of-the-art health apps.  Integrating these two contributions will produce a stress app that potentially offers users considerable leverage in decreasing distress and increasing eustress.  We further aim to develop forms of the app that preclude health intervention disparities across SES levels.

Initially, the app will collect situations in a user’s life where they experience distress and eustress.  On subsequent occasions, users will evaluate these situations with respect to the stress mechanisms that SAM2 typically assesses (e.g., expectation violation, threat, coping ability, negative affect, rumination, pessimism, judgmentalness).  After performing the SAM2 procedure on a given occasion, users will receive feedback about their levels of distress and eustress, together with information about the specific stress mechanisms most related to their stress levels.  Finally, the app will provide tailored instructions about how to change these predictive patterns so that stress experience shifts increasingly from negative distress to positive eustress. 

Courtney Taylor-Browne Luka wins grant from the TLC Foundation for using the Situated Assessment Method to understand and change compulsive hair pulling

December 2020

In collaboration with her supervisors (Lawrence Barsalou and Jude Stevenson), Courtney Taylor-Browne Luka won a competition for TLC Foundation funds to significantly develop and extend her PhD research.

Title:  Understanding, predicting, and changing hairpulling across specific situations

Synopsis:  Our research aims to understand, predict, and ultimately change hairpulling. Hairpulling behaviours are highly varied, differing in pulling sites, frequency, and duration, not only between individuals but also within. Research has further suggested that hairpulling is highly situation specific, tending to occur more often in some situations than others. To the extent that pulling reflects situational constraints, this suggests measuring and working with it in a situated manner.

Problematically, however, measures that assess hairpulling in individuals are unsituated, meaning that they evaluate hairpulling experiences using items that abstract over specific situations. Take, for example, an item from the Massachusetts General Hospital-Hair Pulling Scale, “On an average day, how often did you actually pull your hair?” To evaluate this item, individuals must abstract over many specific situations they experienced previously to provide an overall judgement across them. By not assessing specific situations, unsituated measures may instead measure intuitive theories about oneself more than experiences of actual pulling situations. Further, unsituated theories are unable to provide much detail about pulling behaviour, such as initiating conditions (e.g., environmental triggers), surrounding actions (e.g., rituals), and outcomes (e.g., changes in emotion). Not capturing situational features of pulling experiences limits our ability to understand an individual’s hairpulling, in turn limiting our ability to accurately predict and ultimately change it. Our project aims to better understand, predict, and change hairpulling behaviour in specific situations.

In previous research, we have developed a new situated approach to measuring hairpulling, whereby individuals no longer abstract over specific situations to produce overall judgements of their hairpulling experience. Instead, individuals rate their experiences of pulling in specific situations (e.g., while watching television, while cleaning the house). Because this approach is grounded in two dimensions of situatedness—situational experience and the situated action cycle—we call it the Situated Assessment Method (SAM²). On the first dimension of situatedness, SAM² assesses a behaviour, such as pulling in specific life situations.  On the second dimension of situatedness SAM² assess the basic phases of the target behaviour in the situation, including environmental cues that trigger it, appraisals and goals that arise from these triggers, emotion and motivation in the body, cognitive and motoric actions to achieve goals, and the outcomes of these actions on the environment and oneself.  Thus, to measure a behaviour like hairpulling, SAM² assesses it in the situations where it occurs across all these phases of the behaviour. Additionally, we measure these phases in ways that reflect three major theoretical perspectives traditionally used to explain trichotillomania: the Comprehensive Behavioural Model (ComB), the Cognitions and Beliefs Model, and the Emotion Regulation Model.

Using the SAM2 method, we construct detailed models of the situational features that best predict pulling for a single individual. Consistent with the ComB model, triggers positively predict pulling/urge across most individuals. Consistent with the Cognitions and Beliefs model, reduced control increases hairpulling for many individuals, with negative feelings about oneself predicting pulling urge/frequency in some individuals. Consistent with the Emotion Regulation Model, pulling/urge to pull is positively related to reduction in negative emotion. Beyond the general trends just described, our results highlight how hairpulling experiences vary tremendously across individuals, while demonstrating that SAM² captures them effectively.

We further propose that SAM² can be used as an effective intervention for trichotillomania, decreasing frequency and urge of pulling. Encouraging individuals to process potential pulling situations in terms of the frequency and urge to pull, together with situational predictors of pulling, such as triggers, control, consequences etc., may help them understand what is happening in their specific pulling situations.  As a result of becoming more consciously aware of situational factors associated with pulling, individuals may become better able to cope effectively with them. Essentially, SAM² offers a behaviour change intervention that can translate into helping individuals anticipate their pulling episodes, together with becoming more aware of the situational features relevant to pulling.  By becoming more aware of how their specific form of pulling operates in specific situations, pullers may become better able to regulate their behaviour.  A study to be performed in the coming year will assess whether SAM2 offers an effective behaviour change intervention.

Besides producing an increased understanding of individual hair pulling that promotes effective behaviour change, SAM2 can also be used to provide feedback that directs individuals to effective interventions for moderating the situational factors most relevant for them. If our research demonstrates that SAM² can be an effective behavioural change intervention, we anticipate that an app utilising SAM² could be used by those who wish to understand their hairpulling and potentially reduce its frequency and associated urges.

New PhD project with Casper Pedersen on establishing situated and generalizable models of stress

October 2020

Casper Pedersen has been awarded a PhD studentship from the University of Glasgow’s Center for Doctoral Training in Socially Intelligent Artificial Agents.  Casper’s supervisory team includes Christoph Scheepers and Lawrence Barsalou (University of Glasgow) and Aleksandar Matic (Koa Health). 

In this project, we combine Generalizability Theory and the Situated Assessment Method to build models of an individual’s distress and eustress.  Of central interest is using this model to measure, predict, and change levels of distress and eustress over time.  At multiple timepoints, individuals provide data about distress and eustress in specific life situations, together with data about associated stress mechanisms.  Our modeling tools then provide feedback to individuals about their stress levels, together with the most highly related stress mechanisms. 

Of central interest is using this information help individuals better understand how distress and eustress emerge in specific life situations.  As individuals become increasingly tuned into their stress experience, they can then use this understanding to initiate various coping strategies and interventions for changing it.  A central goal of this work is identifying methods for shifting experiences of distress to eustress.  We also plan to explore the use of wearable technology that captures physiological data to support measuring, predicting, and changing stress.

To further develop this collaborative effort between academia and industry, we have received additional funding from the University of Glasgow’s Knowledge Exchange Fund (along with the funding from the Center for Doctoral Training).

Jing Chen receives PhD for research on relations between initial mindfulness training and eating

Title:  Effects of brief mindfulness training on the neural activity associated with processing food cues

Supervisor:  Lawrence Barsalou

Date:  June 2019

Universities:  The University of Glasgow supported the research performed in this dissertation, with data collected in the fMRI scanner in the Institute for Neuroscience and Psychology.  Emory University awarded the PhD, where Jing Chen was a PhD student.

Abstract:  A functional magnetic resonance imaging experiment assessed effects of a brief mindfulness intervention on the neural mechanisms that underlie food cue processing.  In a blocked design, an initial training phase asked participants to either normally view or mindfully attend to images of tasty and healthy foods.  In a fast event-related design, a subsequent choice phase asked participants to make speeded choices about whether to eat pictured foods (both tasty and healthy, half from the training phase, half novel).  The results largely supported our hypotheses.  Using the breadth of activation relative to well-matched active baselines (rather than signal intensity relative to resting state baselines), we established a large distributed neural network for food processing that grounds the diverse aspects of food consumption simulations, including the ventral food reward network (taste, olfaction, reward, attention), mentalizing (along the cortical midline), and embodiment including action (across the motor system).  This distributed network was active for both training and choice, for both tasty and healthy foods, for both repeated and novel foods.  Left-hemisphere language areas were also active (although not predicted), implicating linguistic processing of food cues, especially during the training phase for the mindful attention group.  As predicted, tasty foods produced greater neural activity across food processing areas than healthy foods during the training phase.  Surprisingly the choice phase exhibited the opposite pattern, with healthy foods producing larger activations.  Most importantly, mindful attention, relative to normal viewing, produced more neural activity while processing foods during the training phase, but much less neural activity during the subsequent choice phase.  Increased up-front processing for mindful attention during training later led to a large processing off-load during food choice.  Moreover, this effect of mindful attention was much larger for tasty foods than for healthy foods, perhaps because tasty foods offer more conceptual content for mindful attention to process.  Finally, mindful attention operated both as a general cognitive set (generalizing to novel foods) and also via food-specific memories (repetition effect), suggesting two mechanisms that underlie mindful attention effects.  These results shed new light on the mechanisms that underlie early mindfulness practice, while raising many issues for future research.

Source:  Emory University Libraries,

Welcome New Lab Member

We are excited to have Elena Gelibter join our group.

Elena has a background in both fMRI and MEG, and will be performing research that follows up on our recent review article on eating networks in the brain.  Specifically, Elena’s work aims to better establish the ventral reward and dorsal control pathways associated with  processing of food cues, and to assess a variety of issues associated with their use in  food choices.  Further details about Elena can be found here.

Welcome!  It’s great to have another talented researchers in our group, as we develop new research programmes here in Glasgow.

Three New Articles Not So Obviously On Conceptual Processing

Because conceptual processing supports all intelligent activity , something can  be learned about it from studying just about anything. Just pick your favorite topics, look for conceptual processing, and it’s probably there, taking myriad interesting forms. In this spirit, three new articles examine the processes underlying social priming, eating, and contemplative practices. Although it may not always be obvious how conceptual processing is relevant, trust me, it’s there.

Researchers often complain that there are no theories of social priming (assuming that they are first convinced  it exists, which it obviously does). The theory of situated conceptualization offers an account of social priming, proposing that it  reflects the basic process of multimodal pattern completion inferences  operating throughout cognition. Conceptual processing enters in via the contruct of situated conceptualization from grounded cognition, which assumes that conceptual knowledge about situations produces  inferences to guide intelligent action. From this perspective, social priming reflects the use of past situational experience to guide perception, cognition, affect, and action in current situations.

In our literature review of neuroimaging articles on eating and food cues with Jing Chen as the lead author, food concepts can be seen as  implicit representations of what it’s like to consume specific foods, together with the activities and outcomes of doing so.  We argue that a core eating network–consisting of a ventral reward pathway and a dorsal control pathway–underlies diverse eating phenomena, associated with various eating situations and populations. If you read between the lines, perhaps you’ll see the theme that how you conceptualize food determines how you eat (especially in the section on eating goals, but elsewhere as well).

Perhaps the relevance of conceptual processing is least evident in the article on viewing contemplative practices from the perspective of dual-process theories. Again, though, if you read between the lines, it’s everywhere. On the one hand, conceptualizations inhabit the  habitual implicit responses that occur ubiquitously to perceived stimuli. Indeed, the initial conceptual interpretation of a stimulus typically dominates a person’s affective and behavioral responses to it, sometimes creating dysfunctional mental and physical outcomes. On the other hand, conceptual processes are central to understanding, reappraising, and changing how the mind interprets experience. In other words, reconceptualizing experience is central to successful self-regulation. This article illustrates the rich interplay between dual-process theories and Buddhist contemplative practices, and the potentially productive synergy that results from viewing them together.

If you’re interested in exploring any of these articles further,  the references,  abstracts, and links to them follow.

Barsalou, L.W. (2016). Situated conceptualization offers a theoretical account of social priming. Current Opinion in Psychology, 12, 6-11.

The theory of situated conceptualization is introduced, including its core assumptions about the construction and storage of situated conceptualizations, the production of pattern completion inferences in relevant situations, and the implementation of these inferences via multimodal simulation.  The broad applicability of the theory to many phenomena is reviewed, as is its ability to explain individual differences.  The theory is then applied to social priming, showing that the theory provides a natural account of the diverse forms it takes.  The theory also explains why social priming is difficult to define, why it often reflects modulating factors, and why it can be difficult to replicate.  The importance of studying pattern completion inferences in the context of meaningful situated action receives emphasi

Chen, J., Papies, E.K., & Barsalou, L.W. (2016). A core eating network and its modulations underlie diverse eating phenomena. Brain and Cognition, 110, 20-42.

We propose that a core eating network and its modulations account for what is currently known about the neural activity underlying a wide range of eating phenomena in humans.  The core eating network is closely adapted from a network that Kaye, Fudge, and Paulus (2009) proposed to explain the neurocircuitry of eating, including a ventral reward pathway and a dorsal control pathway.  In a review across multiple literatures that focuses on experiments using functional Magnetic Resonance Imaging (fMRI), we first show that neural responses to food cues, such as food pictures, utilize the same core eating network as eating.  Consistent with the theoretical perspective of grounded cognition, food cues activate eating simulations that produce reward predictions about a perceived food and potentially motivate its consumption.  Reviewing additional literatures, we then illustrate how various factors modulate the core eating network, increasing and/or decreasing activity in subsets of its neural areas.  These modulating factors include food significance (palatability, hunger), body mass index (BMI, overweight/obesity), eating disorders (anorexia nervosa, bulimia nervosa, binge eating), and various eating goals (losing weight, hedonic pleasure, healthy living).  By viewing all these phenomena as modulating a core eating network, it becomes possible to understand how they are related to one another within this common theoretical framework.  Finally, we discuss future directions for better establishing the core eating network, its modulations, and their implications for behavior.

Barsalou, L.W. (in press). Understanding contemplative practices from the perspective of dual-process theories.  In J.C. Karremans & E.K. Papies (Eds.), Mindfulness in social psychology. Hove, UK: Psychology Press.

After briefly reviewing the history of dual-process theories in cognitive and social psychology, this chapter explores implications of the dual-process perspective for Buddhist contemplative practices, including mindfulness.  On the one hand, the impulsive and habitual processes in dual-process theories offer a natural account of the phenomena that contemplative practices address (e.g., craving, negative emotion, self-interest, mind wandering).  On the other hand, the regulatory and reflective processes in dual-process theories offer insightful perspective into how contemplative practices modulate these phenomena.  Additionally, dual-process theories offer useful accounts of the constant interplay between habitual and regulatory processing in everyday life, and how contemplative practices establish healthy new cognitive, affective, and behavioral habits that replace less healthy well-entrenched ones.  In turn, contemplative practices—especially the collection of Buddhist practices known as the Eight-Fold Path—provide insight into the nature of habitual processing, and offer provocative ideas for developing interventions to change it.

Four New Articles on Conceptual Processing

If you follow research on conceptual processing from the grounded perspective, four recent articles in press might be of interest.  The first article addresses the debate between grounded and amodal theories, concluding that a successful theory of concepts will include grounding, abstraction, and context-dependent flexibility, while explaining classic conceptual phenomena and making contact with real-world situations.  The second article asks whether human cognition can be reduced to action, and concludes that it can’t, because  diverse representational and other internal processes mediate perception and action, making the impressive range of human actions possible.  The third article presents a theory of situated conceptual processing and demonstrates its broad applicability to cognitive, social, affective, and appetitive behaviors.  The fourth article raises issues for theories of concept composition, arguing that if these theories aspire to psychological plausibility,  they will have to address the content variability, multiple representational forms, and pragmatic  constraint that characterize human conceptual processing.  If you’re interested in exploring any of these articles further,  the references,  abstracts, and links to them follow.

Barsalou, L.W. (2016). On staying grounded and avoiding Quixotic dead ends. Psychonomic Bulletin & Review, 23, 1122-1142.

The fifteen articles in this special issue on The Representation of Concepts illustrate the rich variety of theoretical positions and supporting research that characterize the area.  Although much agreement exists among contributors, much disagreement exists as well, especially about the roles of grounding and abstraction in conceptual processing.  I first review theoretical approaches raised in these articles that I believe are Quixotic dead ends, namely, approaches that are principled and inspired but likely to fail.  In the process, I review various theories of amodal symbols, their distortions of grounded theories, and fallacies in the evidence used to support them.  Incorporating further contributions across articles, I then sketch a theoretical approach that I believe is likely to be successful, which includes grounding, abstraction, flexibility, explaining classic conceptual phenomena, and making contact with real-world situations.  This account further proposes that (1) a key element of grounding is neural reuse, (2) abstraction takes the forms of multimodal compression, distilled abstraction, and distributed linguistic representation (but not amodal symbols), and (3) flexible context-dependent representations are a hallmark of conceptual processing.

Barsalou, L.W. (2016). Can cognition be reduced to action? Processes that mediate stimuli and responses make human action possible. In A. K. Engel, K. J. Friston, & D. Kragic (Eds.), Where’s the action? The pragmatic turn in cognitive science (Strüngmann Forum Reports, Vol. 18, pp. 81-96, J. Lupp, Series Ed.). Cambridge, MA. MIT Press.

After treating action as peripheral for decades, cognitive scientists increasingly appreciate the fundamental roles it plays throughout cognition.  Because action shapes cognitive processes pervasively, some theorists propose that cognition can be reduced to action.  I propose that the central roles of action in human cognition depend on important processes that mediate between stimuli and responses.  From this perspective, the unique features of human cognition do not simply reflect a remarkable potential for action, but also powerful abilities that mediate action in response to the environment.  Sophisticated action results from sophisticated mediation, in particular, from mediating processes associated with representation, conceptualization, internal state attribution, affect, and self-regulation.  Integrated with action systems, these mediating processes endow humans with unusually flexible and powerful means of shaping their physical and social environments.  Without taking these mediating processes into account, it may be difficult, if not impossible, to explain human action.  It may also be difficult to explain basic cognitive phenomena associated with memory, concepts, categorization, symbolic operations, language, problem solving, decision making, motivation, emotion, reward, self, mentalizing, and social cognition.  Instead of reducing cognition to action, an alternative project is to develop a viable theory that does justice to the importance of action in cognition, while integrating mediating processes that complement it.

Barsalou, L.W. (2016). Situated conceptualization: Theory and applications. In Y. Coello & M. H. Fischer (Eds.), Foundations of embodied cognition, Volume 1: Perceptual and emotional embodiment (pp. 11-37). East Sussex, UK: Psychology Press.

This chapter develops the construct of situated conceptualization beyond earlier treatments.  After assumptions about conceptual processing and grounded cognition are addressed, a theoretical framework for situated conceptualization is presented that incorporates simulation, situatedness, local vs. global conceptualization, exemplars vs. abstraction, emergence, pattern completion inferences, and subjective realism.  The broad applicability of this framework is then illustrated using examples of relevant phenomena from the domains of perception, action, cognition, social cognition, affective processing, and appetitive processing.  As these examples illustrate, the processes of constructing situated conceptualizations, storing them, and applying them in new situations appear to be ubiquitous across domains.  These processes offer a natural means of explaining individual differences across domains as well.

Barsalou, L.W. (in press). Cognitively plausible theories of concept composition. In Y. Winter & J. A. Hampton (Eds.), Compositionality and concepts in linguistics and psychology. London: Springer Publishing.

If a theory of conceptual combination aspires to psychological plausibility, it may first need to address several preliminary issues, all of them relatively daunting.  One issue concerns the considerable variability in a concept’s content.  Increasing research suggests that many, if not most, concepts do not have stable cores that remain invariant across situations.  Instead, concepts generally appear to take different forms across situations, sampling dynamically from diverse sources of information.  Across these different forms, no single prototype (much less a rule) may represent a concept.  Instead, many different situation-specific prototypes or exemplars may represent the concept, with important conceptual content distributed across all these representations in the aggregate.  A second issue concerns the form of a concept’s representation.  Although amodal symbols have traditionally been assumed to represent concepts, their plausibility has been increasingly called into question, with challenges from neural nets, grounded cognition, and latent semantic analysis.  Whereas some researchers argue that simulations in the brain’s modal systems represent concepts, others argue that clouds of linguistic forms play this role.  It would not be surprising if all these accounts are correct to some extent, with concepts being represented in multiple forms, each playing important roles.  A final issue concerns relations between concepts and the world.  As concepts become mapped to their instantiations in the environment, they appear to change and evolve with the extensional feedback that results.  Similarly, as concepts operate in the context of situated action, they acquire goal-relevant properties that support effective goal achievement.  Concepts appear to reflect pragmatic constraints as much as they do semantic and logical ones.  These three issues—content variability, multiple representational forms, and pragmatic constraint—appear central to naturally occurring human concepts.  Not only does each issue constitute a significant challenge for explaining individual concepts, together they pose an even more significant challenge for theories of conceptual combination.  How do concepts combine as their content changes, as different representational forms become active, and as pragmatic constraints shape processing?  Arguably, concepts are most ubiquitous and important in combination, relative to isolation.  Indeed, entering into combinations may play central roles in producing the changes in content, form, and pragmatic relevance observed for individual concepts.  Developing a theory of conceptual combination that embraces and illuminates these issues would not only constitute a significant contribution to the study of concepts, it would also provide insight into the nature of human cognition.