In phase I clinical trials, healthy volunteers are dosed with investigational drugs and subjected to blood draws and other bodily monitoring procedures. In exchange, they are paid. Healthy volunteers are, in a very direct sense, selling access to their bodies for pharmaceutical companies and their associates to run drugs through. In his ethnographic study of socalled professional guinea pigs, Roberto Abadie writes, "Paid volunteers are well aware of the demand for an idealized, perfectly healthy volunteer. They also realize that their (...) body is a valued commodity in clinical trials research". It is perhaps surprising, then, that commodification is little discussed in the bioethics literature on phase I... (shrink)

While risk of harm is an important focus for whether clinical research on humans can and should proceed, there is uncertainty about what constitutes harm to a trial participant. In Phase I trials on healthy volunteers, the purpose of the research is to document and measure safety concerns associated with investigational drugs, and participants are financially compensated for their enrollment in these studies. In this article, we investigate how characterizations of harm are narrated by healthy volunteers in the context of (...) the adverse events they experience during clinical trials. Drawing upon qualitative research, we find that participants largely minimize, deny, or re-attribute the cause of these AEs. We illustrate how participants' interpretations of AEs may be shaped both by the clinical trial environment and their economic motivation to participate. While these narratives are emblematic of the larger ambiguity surrounding harm in the context of clinical trial participation, we argue that these interpretations also problematically maintain the narrative of the safety of clinical trials, the ethics of testing investigational drugs on healthy people, and the rigor of data collected in the specter of such ambiguity. (shrink)

Little is known about the mechanisms by which psychology graduate programs transmit responsible conduct of research (RCR) values. A national sample of 968 current students and recent graduates of mission-diverse doctoral psychology programs completed a Web-based survey on their research ethics challenges, perceptions of RCR mentoring and department climate, whether they were prepared to conduct research responsibly, and whether they believed psychology as a discipline promotes scientific integrity. Research experience, mentor RCR instruction and modeling, and department RCR policies predicted student (...) RCR preparedness. Mentor RCR instruction, department RCR policies, and faculty modeling of RCR behaviors predicted confidence in the RCR integrity of the discipline. Implications for training are discussed. (shrink)

Researchers have iterated that the future of synthetic biology and biotechnology lies in novel consumer applications of crossing biology with engineering. However, if the new biology’s future is to be sustainable, early and serious efforts must be made towards social sustainability. Therefore, the crux of new applications of synthetic biology and biotechnology is public understanding and acceptance. The RASVaccine is a novel recombinant design not found in nature that re-engineers a common bacteria to produce a strong immune response in humans. (...) Synthesis of the RASVaccine has the potential to improve public health as an inexpensive, non-injectable product. But how can scientists move forward to create a dialogue of creating a ‘common sense’ of this new technology in order to promote social sustainability? This paper delves into public issues raised around these novel technologies and uses the RASVaccine as an example of meeting the public with a common sense of its possibilities and limitations. (shrink)

Researchers have iterated that the future of synthetic biology and biotechnology lies in novel consumer applications of crossing biology with engineering. However, if the new biology’s future is to be sustainable, early and serious efforts must be made towards social sustainability. Therefore, the crux of new applications of synthetic biology and biotechnology is public understanding and acceptance. The RASVaccine is a novel recombinant design not found in nature that re-engineers a common bacteria to produce a strong immune response in humans. (...) Synthesis of the RASVaccine has the potential to improve public health as an inexpensive, non-injectable product. But how can scientists move forward to create a dialogue of creating a ‘common sense’ of this new technology in order to promote social sustainability? This paper delves into public issues raised around these novel technologies and uses the RASVaccine as an example of meeting the public with a common sense of its possibilities and limitations. (shrink)

Drawing upon two independent national samples of 201 and 241 psychology graduate students, this article describes the development and psychometric evaluation of 4 Web-based student self-report scales tapping student socialization in the responsible conduct of research (RCR) with human participants. The Mentoring the Responsible Conduct of Research Scale (MRCR) is composed of 2 subscales assessing RCR instruction and modeling by research mentors. The 2 subscales of the RCR Department Climate Scale (RCR-DC) assess RCR department policies and faculty and student RCR (...) practices. The RCR Preparedness scale (RCR-P) and the RCR Field Integrity scale (RCR-FI) measure respectively students' confidence in their ability to conduct research responsibly and their belief in the RCR integrity of psychology as a discipline. Factor analysis, coefficient alphas, correlations, and multiple regression analyses demonstrated each of the scales had good internal consistency and concurrent and construct validity. (shrink)

This article empirically examines how healthy volunteers evaluate and make sense of the risks of phase I clinical drug trials. This is an ethically important topic because healthy volunteers are exposed to risk but can gain no medical benefit from their trial participation. Based on in-depth qualitative interviews with 178 healthy volunteers enrolled in various clinical trials, we found that participants focus on myriad characteristics of clinical trials when assessing risk and making enrolment decisions. These factors include the short-term and (...) long-term effects; required medical procedures; the type of trial, including its design, therapeutic area of investigation, and dosage of the drug; the amount of compensation; and trust in the research clinic. In making determinations about the study risks, participants rely on information provided during the consent process, their own and others’ experiences in clinical trials, and comparisons among studies. Our findings indicate that the informed consent process succeeds in communicating well about certain types of risk information while simultaneously creating lacunae that are problematically filled by participants through their collective experiences and assumptions about risk. We discuss the ethical implications of these findings and make recommendations for improving the consent process in healthy volunteer trials. (shrink)

Objective: To determine whether a moral reasoning exercise can improve response quality to surveys of healthcare priorities Methods: A randomised internet survey focussing on patient age in healthcare allocation was repeated twice. From 2574 internet panel members from the USA and Canada, 2020 (79%) completed the baseline survey and 1247 (62%) completed the follow-up. We elicited respondent preferences for age via five allocation scenarios. In each scenario, a hypothetical health planner made a decision to fund one of two programmes identical (...) except for average patient age (35 vs 65 years). Half of the respondents (intervention group) were randomly assigned to receive an additional moral reasoning exercise. Responses were elicited again 7 weeks later. Numerical scores ranging from –5 (strongest preference for younger patients) to +5 (strongest preference for older patients); 0 indicates no age preference. Response quality was assessed by propensity to choose extreme or neutral values, internal consistency, temporal stability and appeal to prejudicial factors. Results: With the exception of a scenario offering palliative care, respondents preferred offering scarce resources to younger patients in all clinical contexts. This preference for younger patients was weaker in the intervention group. Indicators of response quality favoured the intervention group. Conclusions: Although people generally prefer allocating scarce resources to young patients over older ones, these preferences are significantly reduced when participants are encouraged to reflect carefully on a wide range of moral principles. A moral reasoning exercise is a promising strategy to improve response quality to surveys of healthcare priorities. (shrink)

The article "Picking and Choosing Among Phase I Trials", written by Jill A. Fisher, Torin Monahan and Rebecca L. Walker, was originally published Online First without Open Access. After publication in volume 16, issue 4, page 535-549 the author decided to opt for Open Choice and to make the article an Open Access publication.

Background The ethical use both of human and non-human animals in research is predicated on the assumption that it is of a high quality and its projected benefits are more significant than the risks and harms imposed on subjects. Yet questions remain about whether and how IRBs and IACUCs should consider the scientific value of proposed research studies.Methods We draw upon 45 interviews with IRB and IACUC members and researchers with oversight experience about their perceptions of their own roles in (...) reviewing the quality and value of scientific protocols. Interview transcripts were memoed to highlight specific findings, which were then used to identify key themes through an iterative process.Results IRB and IACUC members expressed broad trust in the need for and value of research, and they often assumed that protocols had social value or that prior review, especially when associated with funding, affirmed both the rigor and merit of those protocols. Some oversight members also took an explicit stance against scientific review by stating that such review is not within the regulatory mandates governing their parts in the oversight system. Yet other interviewees expressed uneasiness about the current paradigm for evaluating the quality and overall value of science, suggesting that IRB and IACUC members perceive gaps in the oversight systems.Conclusions These findings reveal many similarities in how IRB and IACUC members understand the roles and limitations of their respective oversight committees. We conclude with a discussion of how the lack of a clear mandate regarding scientific review within US federal regulations may undermine ethical engagement of whether human and animal research is scientifically justified, resulting in a “mission lapse” wherein no organizational body is clearly responsible for ensuring that the research being conducted has the potential to advance science and benefit society. (shrink)

Libertarianism has a problem, perhaps an insurmountable one, and its problem lies squarely in the domain from which it is sourced: the intellectual and political elite of the West. As such, it rests on an ontological viewpoint far outside the purview and experience of quotidian man. Furthermore, it rests on an epistemology of the person as sovereign, Natural Law, which requires a concomitant education or understanding of the Classics, or at least self-awareness and the ability to think logically. Many non-intellectuals (...) are either uninterested or incapable of following the Libertarian arguments of personal sovereignty and instead submit. This unconscious submission to the authority of a government, father figure, or other self-appointed “authority” relieves the individual of the psychological pain of breaking out of the herd. C. G. Jung (1875-1961) was adamant that to be an individual is a radical act: “To develop one’s own personality is indeed an unpopular undertaking, a deviation that is highly uncongenial to the herd, an eccentricity smelling of the cenobite, as it seems to the outsider [11, Para. 298]. Further, Alexander Hamilton (1755 or 1747-1804) noted that the elite are more than happy to have the masses submit to their authority without question as it advances their control: “a fondness for power is implanted in most men, and it is natural to abuse it when acquired” [9]. The rest of this article explores this psychosis of authority and how Libertarianism suffers in popularity as a result. (shrink)

Phase 1 healthy volunteer clinical trials—which financially compensate subjects in tests of drug toxicity levels and side effects—appear to place pressure on each joint of the moral framework justifying research. In this article, we review concerns about phase 1 trials as they have been framed in the bioethics literature, including undue inducement and coercion, unjust exploitation, and worries about compromised data validity. We then revisit these concerns in light of the lived experiences of serial participants who are income-dependent on phase (...) 1 trials. We show how participant experiences shift attention from discrete exchanges, behaviors, and events in the research enterprise to the ongoing and dynamic patterns of serial participation in which individual decision-making is embedded in collective social and economic conditions and shaped by institutional policies. We argue in particular for the ethical significance of structurally diminished voluntariness, routine powerlessness in setting the terms of exchange, and incentive structures that may promote pharmaceutical interests but encourage phase 1 healthy volunteers to skirt important rules. (shrink)

The COVID-19 pandemic has necessitated innovations in data collection protocols, including use of virtual or remote visits. Although developmental scientists used virtual visits prior to COVID-19, validation of virtual assessments of infant socioemotional and language development are lacking. We aimed to fill this gap by validating a virtual visit protocol that assesses mother and infant behavior during the Still Face Paradigm and infant receptive and expressive communication using the Bayley-III Screening Test. Validation was accomplished through comparisons of data collected during (...) in-person laboratory visits and virtual visits conducted via Zoom. Of the 119 mother-infant dyads who participated, 73 participated in lab visits only, 13 participated in virtual visits only, and 33 dyads participated in a combination of lab and virtual visits across four time points. Maternal perspectives of, and preferences for, virtual visits were also assessed. Proportions of missing data were higher during virtual visits, particularly for assessments of infant receptive communication. Nonetheless, comparisons of virtual and laboratory visits within a given time point indicated that mothers and infants showed similar proportions of facial expressions, vocalizations and directions of gaze during the SFP and infants showed similar and expected patterns of behavioral change across SFP episodes. Infants also demonstrated comparable expressive and receptive communicative abilities across virtual and laboratory assessments. Maternal reports of ease and preference for virtual visits varied by infant age, with mothers of 12-month-old infants reporting, on average, less ease of virtual visits and a preference for in-person visits. Results are discussed in terms of feasibility and validity of virtual visits for assessing infant socioemotional and language development, and broader advantages and disadvantages of virtual visits are also considered. (shrink)

This interview with media anthropologist, Rebecca L. Stein, conducted by Noa Levin and Andrew Fisher in Spring 2023, takes her recent book Screenshots: State Violence on Camera in Israel and Palestine (2021) as its starting point in order to explore issues of state violence and the militarization of social media in Israel/Palestine. This book marks the culmination of a decade-long research project into the camera dreams introduced by digital imaging technologies and the fraught histories of their disillusionment. Stein discusses (...) the way her research has critically conceptualized the recent history of hopes invested in the digital image in this geopolitical context, by the occupier as much as the occupied, and charts the failures and mistakes, obstructions and appropriations that characterize the conflicted visual cultures of Israel/Palestine. (shrink)

The prospect of extra‐terrestrial intelligence has become a central topic of scientific investigation and popular speculation. This has generated questions of ethical and theological significance that now receive growing coverage. Throughout his writings, Karl Rahner remained open to the prospect that the process of cosmic evolution had yielded sentient life form in other galaxies. He argued against any theological veto on this notion, while also distinguishing the existential significance of such life forms from that of angels. Furthermore, the possibility of (...) multiple incarnations is raised though not affirmed. With its christological intensity, his theology seems to militate against any repetition of the incarnation. This essay examines some of the arguments for and against the possibility of multiple incarnations, before assessing the current state of the extra‐terrestrial intelligence debate. In the light of inconclusive scientific findings, the cautionary position of Rahner is re‐affirmed. (shrink)

We discuss our surgical philosophy concerning the subtle interplay between the size of the surgical margin taken and the resultant morbidity from ablative oncological. procedures, which is ever more evident in the treatment of head and neck malignancy. The extent of tissue resection is determined by the "trade off" between cancer control and the perioperative, functional and aesthetic morbidity and mortality of the surgery. We also discuss our dilemmas concerning recent minimally invasive endoscopic microsurgical. techniques for the trans-oral laser removal. (...) or co-ablation of aero-digestive tract tumours, which result in a minimal. surgical margin of oncological clearance. By a process of inductive argument as to the nature of the surgical margin, we consider whether the risks of taking a lesser margin with adjuvant therapy is justified by the attendant gain in reduced surgical morbidity and the possible costs in tumour control. (c) 2006 Elsevier Ltd. All rights reserved. (shrink)

In The Art Instinct, Denis Dutton promoted a theoretical framework that “has more validity, more power, and more possibilities than the hermetic discourse that deadens so much of the humanities.”1 This framework is Charles Darwin’s theory of evolution by natural and sexual selection. Dutton proposed to seek “human universals that underlie the vast cacophony of cultural differences and across the globe” (AI, p. 39), based on a shared, evolved human nature.This contrasts with the relativistic presumptions of those falling under the (...) shadow of Margaret Mead and Clifford Geertz, or “the dogmas of Freud, the speculations of Jung, the sterile formulations of behaviorism, all variously empty or misleading” (p. 37). Also .. (shrink)

A new temperament construct based on recent brain physiology literature has been investigated using the Fisher Temperament Inventory (FTI). Four collections of behaviors emerged, each associated with a specific neural system: the dopamine, serotonin, testosterone, and estrogen/oxytocin system. These four temperament suites have been designated: (1) Curious/Energetic, (2) Cautious/Social Norm Compliant, (3) Analytical/Tough-minded, and (4) Prosocial/Empathetic temperament dimensions. Two functional magnetic resonance imaging (fMRI) studies have suggested that the FTI can measure the influence of these neural systems. In this (...) paper, to further the behavioral validation and characterization of the four proposed temperament dimensions, we measured correlations with five variables: (1) gender; (2) level of education; (3) religious preference; (4) political orientation; (5) the degree to which an individual regards sex as essential to a successful relationship. Subjects were 39,913 anonymous members of a US Internet dating site and 70,000+ members in six other countries. Correlations with the five variables characterize the FTI and are consistent with mechanisms using the proposed neuromodulators. We also report on an analysis between the FTI and the NEO-Five Factor Inventory, using a college sample ( n = 215), which showed convergent validity. The results provide novel correlates not available in other questionnaires: religiosity, political orientation, and attitudes about sex in a relationship. Also, an Eigen analysis replicated the four clusters of co-varying items. The FTI, with its broad systems and non-pathologic factors complements existing personality questionnaires. It provides an index of some brain systems that contribute to temperament, and may be useful in psychotherapy, business, medicine, and the legal community. (shrink)

Objective: To audit doctors’ knowledge of informed consent.Design: 10 consent scenarios with “true”, “false”, or “don’t know” answers were completed by doctors who care for children at a large district general hospital. These questions tested clinicians’ knowledge of who could give consent in different clinical situations.Setting: Royal United Hospital, Bath, UK.Results: 51 doctors participated . Paediatricians scored higher than other clinicians . Only 36% of paediatricians and 8% of other clinicians realised that the biological father of a child born before (...) 1 December 2003 needed a court order or a parental responsibility agreement to acquire parental responsibility, and thus be able to consent on behalf of his child, if he was not married to the child’s mother. Non-paediatric clinicians were unsure or incorrect when tested on situations where people with parental responsibility do not agree, or where young people , who are Fraser competent do not want to consult their parents. Most clinicians did not know that the parents of a 20-year-old man with severe learning difficulties are unable to consent to surgery on his behalf, and many non-paediatricians were unclear on who could give consent when a child lived with foster parents.Conclusion: Clinicians who obtain consent for the treatment of children need to increase their knowledge on who is able to give informed consent to ensure best practice. (shrink)

Since Tversky argued that similarity judgments violate the three metric axioms, asymmetrical similarity judgments have been particularly challenging for standard, geometric models of similarity, such as multidimensional scaling. According to Tversky, asymmetrical similarity judgments are driven by differences in salience or extent of knowledge. However, the notion of salience has been difficult to operationalize, especially for perceptual stimuli for which there are no apparent differences in extent of knowledge. To investigate similarity judgments between perceptual stimuli, across three experiments, we collected (...) data where individuals would rate the similarity of a pair of temporally separated color patches. We identified several violations of symmetry in the empirical results, which the conventional multidimensional scaling model cannot readily capture. Pothos et al. proposed a quantum geometric model of similarity to account for Tversky's findings. In the present work, we extended this model to a more general framework that can be fit to similarity judgments. We fitted several variants of quantum and multidimensional scaling models to the behavioral data and concluded in favor of the quantum approach. Without further modifications of the model, the best-fit quantum model additionally predicted violations of the triangle inequality that we observed in the same data. Overall, by offering a different form of geometric representation, the quantum geometric framework of similarity provides a viable alternative to multidimensional scaling for modeling similarity judgments, while still allowing a convenient, spatial illustration of similarity. (shrink)

Against the backdrop of a global pandemic, this study investigates how U.S. higher education leaders have centered their crisis management on values and guiding ethical principles. We conducted 55 in-depth interviews with leaders from 30 U.S. higher education institutions, with most leaders participating in two interviews. We found that crisis plans created prior to the COVID-19 pandemic were inadequate due to the long duration and highly uncertain nature of the crisis. Instead, higher education leaders applied guiding principles on the fly (...) to support their decision-making. If colleges and universities infuse shared values into their future crisis plans, they will not have to develop a moral compass on the fly for the next pandemic. This paper suggests the following somewhat universal shared values: engage in accuracy, transparency, and accountability; foster deliberative dialog; prioritize safety; support justice, fairness, and equity; and engage in an ethic of care. To navigate ethics tensions, leaders need to possess crisis-relevant expertise or ensure that such expertise is present among crisis management team members. Standing up formal ethics committees composed of diverse stakeholders also is instrumental in navigating tensions inherent in crises. The next pandemic is already on the horizon according to experts. Through infusing values into future crisis plans, higher education leaders can be confident that their responses will be grounded in their communities’ shared values. (shrink)

In his recent book, Frame It Again: New Tools for Rational Decision-Making, J. L. Bermúdez argues that it can be rational to evaluate the same thing differently when it is described using alternati...

ObjectiveApproximately half of all people living with amyotrophic lateral sclerosis experience persistent or recurrent emotional distress, yet little is known about the psychological processes that maintain emotional distress in this population. The self-regulatory executive functioning model specifies that maladaptive metacognitive beliefs and processes are central to the development and maintenance of emotional distress. This study explored whether maladaptive metacognitive beliefs are associated with emotional distress after controlling for demographic factors, time since diagnosis, and current level of physical functioning.DesignIn a cross-sectional (...) design, 75 adults with a diagnosis of ALS completed self-report questionnaires. Participants had a mean age of 60.40 years, mean duration of symptoms 63.92 months, and male:female gender ratio of 14:11.Main Outcome MeasuresQuestionnaires assessed emotional distress, physical functioning, repetitive negative thinking, metacognitive beliefs, and demographic factors.ResultsMaladaptive metacognitive beliefs explained additional variance in emotional distress after controlling for age, gender, time since diagnosis, physical functioning, and repetitive negative thinking. Repetitive negative thinking partially mediated the relationships between positive and negative metacognitive beliefs and emotional distress.ConclusionsThese data support the utility of the metacognitive model in understanding emotional distress in people with ALS. Examination of the temporal relationship between maladaptive metacognitive beliefs and emotional distress in people living with ALS may help to guide the development of therapeutic approaches. (shrink)

According to Roberts, self-experimentation is a viable tool for idea generation in the behavioral sciences. Here we discuss some limitations of this assertion, as well as particular design and data-analytic shortcomings of his experiments.

Eating behaviors evolve during the first years of life as biological and behavioral processes directed towards meeting requirements for health and growth. For the vast majority of human history, food scarcity has constituted a major threat to survival, and human eating behavior and child feeding practices have evolved in response to this threat. Because infants are born into a wide variety of cultures and cuisines, they come equipped as young omnivores with a set of behavioral predispositions that allow them to (...) learn to accept the foods made available to them. During historical conditions of scarcity, family life and resources were devoted to the procurement and preparation of foods, which are often low in energy, nutrients, and palatability. In sharp contrast, today in non-Third World countries children's eating habits develop under unprecedented conditions of dietary abundance, where palatable, inexpensive, ready-to-eat foods are readily available. (shrink)

The Latin Trinity (LT) and the Social Trinity (ST) represent the two dominant approaches for interpreting the doctrine of the Trinity in contemporary philosophical theology. Both approaches have consequences for Christian theology, however, and I believe that neither sufficiently overcomes the charges of modalism or tritheism, respectively. Moreover, the charge of the overall logical incoherency of the doctrine of the Trinity remains a viable criticism. In order to defend the doctrine of the Trinity against charges of incoherency, while avoiding the (...) modalistic and tritheistic leanings of the LT and ST models, I argue that the unitary nature of God‐as‐three‐hypostases is best understood in terms of a relationship of supervenience between the revelation of (1) Deut. 6:4 and (2) the Gospel of John. The Hypostases of the Trinity supervene on the unitary identity of God insofar as to be ‘God’ is to entail the perichoretic relationship of unbegottenness, begottenness, and spiratation (procession). The Supervenient Trinity (SvT), as an analogical model, provides a way to understand God as (1) and (2) that better avoids the modalist and tritheistic difficulties raised by the LT and the ST approaches. (shrink)

ABSTRACT Online research has become a critical recruitment modality for understanding and reducing health disparities among hidden populations most at risk for HIV infection. There is a lack of consensus and guidelines for the responsible conduct of online recruitment for HIV risk populations. Using semi-structured phone interviews, this study drew on the experiences of principal investigators engaged in online HIV research to illuminate scientific and ethical benefits and challenges of social media recruitment. Using Thematic Analysis five major themes emerged: sampling (...) advantages and disadvantages; challenges of data integrity; control of privacy protections; researcher competence and responsibility; and resources. (shrink)

BackgroundDespite rapid growth of the scientific literature, no consensus guidelines have emerged to define the optimal criteria for editors to grade submitted manuscripts. The purpose of this project was to assess the peer reviewer metrics currently used in the surgical literature to evaluate original manuscript submissions.MethodsManuscript grading forms for 14 of the highest circulation general surgery-related journals were evaluated for content, including the type and number of quantitative and qualitative questions asked of peer reviewers. Reviewer grading forms for the seven (...) surgical journals with the higher impact factors were compared to the seven surgical journals with lower impact factors using Fisher’s exact tests.ResultsImpact factors of the studied journals ranged from 1.73 to 8.57, with a median impact factor of 4.26 in the higher group and 2.81 in the lower group. The content of the grading forms was found to vary considerably. Relatively few journals asked reviewers to grade specific components of a manuscript. Higher impact factor journal manuscript grading forms more frequently addressed statistical analysis, ethical considerations, and conflict of interest. In contrast, lower impact factor journals more commonly requested reviewers to make qualitative assessments of novelty/originality, scientific validity, and scientific importance.ConclusionSubstantial variation exists in the grading criteria used to evaluate original manuscripts submitted to the surgical literature for peer review, with differential emphasis placed on certain criteria correlated to journal impact factors. (shrink)

Speech disfluencies can signal that a speaker is about to refer to something difficult to name. In two experiments, we found evidence that 4-year-olds, like adults, flexibly interpret a particular partner’s disfluency based on their estimate of that partner’s knowledge, derived from the preceding conversation. In entrainment trials, children established partner-specific shared knowledge of names for tangram pictures with one or two adult interlocutors. In each test trial, an adult named one of two visible tangrams either fluently or disfluently while (...) children’s eye-movements were monitored. We manipulated speaker knowledge in the test trials. In Experiment 1, the test-trial speaker was the same speaker from entrainment or a naïve experimenter; in Experiment 2, the test-trial speaker had been one of the child’s partners in entrainment and had seen half of the tangrams. When hearing disfluent expressions, children looked more at a tangram that was unfamiliar from the speaker’s perspective; this systematic disfluency effect disappeared in Experiment 1 when the speaker was entirely naïve, and depended on each speaker’s entrainment experience in Experiment 2. These findings show that 4-year-olds can keep track of two different partners’ knowledge states, and use this information to determine what should be difficult for a particular partner to name, doing so efficiently enough to guide online interpretation of disfluent speech. (shrink)