Replies to commentators on <Emphasis Type="Italic">A Virtue Epistemology</Emphasis> (Oxford University Press, 2007)

Paul Boghossian discusses critically my account of intuition as a source of epistemic status. Stewart Cohen takes up my views on skepticism, on dreams, and on epistemic competence and competences and their relation to human knowledge. Hilary Kornblith focuses on my animal/reflective distinction, and, along with Cohen, on my comparison between how dreams might mislead us and how other bad epistemic contexts can do so. In this paper I offer replies to my three critics.

Stimulation of the lateral geniculate,superior colliculus,or visual cortex is sufficient for eyeblink conditioning in rats

The role of the cerebellum in eyeblink conditioning is well established. Less work has been done to identify the necessary conditioned stimulus (CS) pathways that project sensory information to the cerebellum. A possible visual CS pathway has been hypothesized that consists of parallel inputs to the pontine nuclei from the lateral geniculate nucleus (LGN), superior colliculus (SC), pretectal nuclei, and visual cortex (VCTX) as reported by Koutalidis and colleagues in an earlier paper. The following experiments examined whether electrical stimulation of neural structures in the putative visual CS pathway can serve as a sufficient CS for eyeblink conditioning in rats. Unilateral stimulation of the ventral LGN (Experiment 1), SC (Experiment 2), or VCTX (Experiment 3) was used as a CS paired with a periorbital shock unconditioned stimulus. Stimulation was delivered to the hemisphere contralateral to the conditioned eye. Rats in all experiments were given five 100-trial sessions of paired or unpaired eyeblink conditioning with the stimulation CS followed by three paired sessions with a light CS. Stimulation of each visual area when paired with the unconditioned stimulus supported acquisition of eyeblink conditioned responses (CRs) and substantial savings when switched to a light CS. The results provide evidence for a unilateral parallel visual CS pathway for eyeblink conditioning that includes the LGN, SC, and VCTX inputs to the pontine nuclei.Pavlovian eyeblink (eyelid closure and nictitating membrane movement) conditioning is established by pairing a conditioned stimulus (CS), usually a tone or light, with an unconditioned stimulus (US) that elicits the eyeblink reflex. The eyeblink conditioned response (CR) emerges over the course of paired training, occurs during the CS, and precedes the US (Gormezano et al. 1962; Schneiderman et al. 1962). Neurobiological investigations of Pavlovian eyeblink conditioning have primarily focused on the cerebellum, which is the site of memory formation and storage (Thompson 2005). The anterior interpositus nucleus is necessary for acquisition and retention of the eyeblink CR (Lavond et al. 1985; Krupa and Thompson 1997; Freeman Jr. et al. 2005; Thompson 2005; Ohyama et al. 2006). Lobule HVI and the anterior lobe of the cerebellar cortex (lobules I–V) contribute to acquisition, retention, and timing of the CR (McCormick and Thompson 1984; Perrett et al. 1993; Perrett and Mauk 1995; Attwell et al. 1999, 2001; Medina et al. 2000; Nolan and Freeman Jr. 2005; Nolan and Freeman 2006). The brainstem nuclei that comprise the proximal ends of the CS and US input pathways to the cerebellum have also been identified.The pontine nuclei (PN) and inferior olive (IO) receive CS and US information, respectively, and are the primary sensory relays into the interpositus nucleus and cerebellar cortex (Thompson 2005). Conditioned stimulus information converges in the PN, which receives projections from lower brainstem, thalamus, and cerebral cortex (Glickstein et al. 1980; Brodal 1981; Schmahmann and Pandya 1989; Knowlton et al. 1993; Campolattaro et al. 2007). The lateral pontine nuclei (LPN) are the sources of auditory CS information projected into the cerebellum. Lesions of the LPN block CR retention to a tone CS, but have no effect on CRs to a light CS (Steinmetz et al. 1987). Thus, CS inputs from different sensory modalities may be segregated at the level of the PN. Neurons in the PN project CS information into the contralateral cerebellum via mossy fibers in the middle cerebellar peduncle that synapse primarily on granule cells in the cerebellar cortex and on neurons in the deep nuclei (Bloedel and Courville 1981; Brodal 1981; Steinmetz and Sengelaub 1992). Stimulation of the PN acts as a supernormal CS supporting faster CR acquisition than conditioning with peripheral stimuli (Steinmetz et al. 1986, 1989; Rosen et al. 1989; Steinmetz 1990; Tracy et al. 1998; Freeman Jr. and Rabinak 2004). The primary focus of these experiments was to investigate the most proximal components of the CS pathway in eyeblink conditioning. There has been less emphasis on identifying the critical CS pathways that project information to the PN.Recent studies using lesions, inactivation, stimulation, and neural tract tracing have provided evidence that the auditory CS pathway that is necessary for acquisition and retention of eyeblink conditioning is comprised of converging inputs to the medial auditory thalamic nuclei (MATN), and a direct ipsilateral projection from the MATN to the PN (Halverson and Freeman 2006; Campolattaro et al. 2007; Freeman et al. 2007; Halverson et al. 2008). Unilateral lesions of the MATN, contralateral to the conditioned eye, block acquisition of eyeblink CRs to a tone CS but have no effect on conditioning with a light CS (Halverson and Freeman 2006). Inactivation of the MATN with muscimol blocks acquisition and retention of CRs to an auditory CS, and decreases metabolic activity in the PN (Halverson et al. 2008). The MATN has a direct projection to the PN and stimulation of the MATN supports rapid CR acquisition (Campolattaro et al. 2007). Our current model of the auditory CS pathway consists of converging inputs to the MATN, and direct unilateral thalamic input to the PN (Halverson et al. 2008).Less work has been done to identify the visual CS pathway necessary for eyeblink conditioning. A possible parallel visual CS pathway has been hypothesized, which includes parallel inputs to different areas of the PN from the lateral geniculate nucleus (LGN), superior colliculus (SC), visual cortex (VCTX), and pretectal nuclei (Koutalidis et al. 1988). In the Koutalidis et al. study, lesions of the LGN, SC, VCTX, or pretectal nuclei alone had only a partial effect on CR acquisition with a light CS. Lesions of any two of these structures together produced a more severe impairment on acquisition and combined lesions of all of these areas completely blocked CR acquisition to a light CS (Koutalidis et al. 1988). Each visual area investigated in the Koutalidis et al. study has a direct projection to the PN that could be important for eyeblink conditioning. The ventral LGN projects to the medial, and to a lesser extent, the lateral PN (Graybiel 1974; Wells et al. 1989). The superficial, intermediate, and deep layers of SC send projections to both the dorsomedial and dorsolateral PN (Redgrave et al. 1987; Wells et al. 1989). The VCTX has a direct projection to the rostral and lateral portions of the PN (Glickstein et al. 1972; Baker et al. 1976; Mower et al. 1980; Wells et al. 1989). The pretectal nuclei also have a direct projection to both the medial and lateral PN (Weber and Harting 1980; Wells et al. 1989). However, stimulation of the anterior pretectal nucleus is not an effective CS for eyeblink conditioning (Campolattaro et al. 2007). The failure to establish conditioning with stimulation of the anterior pretectal nucleus as a CS suggests that there may be differences in the efficacy of the various visual inputs to the PN for cerebellar learning. The following experiments investigated the sufficiency of stimulation of the LGN, SC, or primary VCTX as a CS for eyeblink conditioning in rats.     

Determining risk in pediatric research with no prospect of direct benefit: time for a national consensus on the interpretation of federal regulations

United States federal regulations for pediatric research with no prospect of direct benefit restrict institutional review board (IRB) approval to procedures presenting: 1) no more than "minimal risk" ( section sign 45CFR46.404); or 2) no more than a "minor increase over minimal risk" if the research is commensurate with the subjects' previous or expected experiences and intended to gain vitally important information about the child's disorder or condition ( section sign 45CFR46.406) (DHHS 2001). During the 25 years since their adoption, these regulations have helped IRBs balance subject protections with the pursuit of scientific knowledge to advance children's welfare. At the same time, inconsistency in IRB application of these regulations to pediatric protocols has been widespread, in part because of the ambiguity of the regulatory language. During the past decade, three federally-charged committees have addressed these ambiguities: 1) the National Human Research Protections Advisory Committee (NHRPAC) (Washington, DC), 2) the Institute of Medicine (IOM) Committee on the Ethical Conduct of Clinical Research Involving Children (Washington, DC); and 3) the United States Department of Health and Human Services Secretary's Advisory Committee for Human Research Protections (SACHRP) (Washington, DC). The committees have reached similar conclusions on interpretation of language within regulations section sign section sign 45CFR46.404 and 406; these conclusions are remarkably consistent with recent international recommendations and those of the original National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research (1977) report from which current regulations are based. Drawing on the committees' public reports, this article identifies the ethical issues posed by ambiguities in regulatory language, summarizes the committees' deliberations, and calls for a national consensus on recommended criteria.     

Body image and explicit and implicit anti-fat attitudes: the mediating role of physical appearance comparisons

Prejudice against overweight people is rife. However, there is a paucity of research on the underlying reasons for it. In two studies the relationship between body image, the tendency to make physical appearance-related comparisons (PACS), and both explicit and implicit anti-fat attitudes was examined. In Study 1 (n = 227) people with a high tendency to make physical appearance-related comparisons (high PACS scorers) reported lower self-appearance evaluation, but higher appearance orientation and explicit anti-fat attitudes. The PACS fully mediated the relationship between appearance orientation and explicit anti-fat attitudes. Study 2 (n = 134) found that the PACS also mediated the relationship between appearance orientation and implicit anti-fat attitudes. Thus, individual differences in factors such as body image and the tendency to make appearance-related comparisons, appear to play a central role in both explicit and implicit anti-fat attitudes.     

The Coming-Out Process and Its Adaptational and Health-Related Associations Among Gay, Lesbian, and Bisexual Youths: Stipulation and Exploration of a Model

A model is proposed and explored that links the coming-out process to the psychological functioning (i.e., self-esteem and distress) and sexual behaviors of gay, lesbian, and bisexual youths recruited from gay-focused community-based and college organizations in New York City. The coming-out process is multidimensional, consisting, as defined here, of involvement in gay/lesbian activities, attitudes toward homosexuality, comfort with homosexuality, self-disclosure of sexual identity to others, and sexual identity. The coming-out dimensions were related to self-esteem, distress, and unprotected sexual behaviors. In addition, the relations between the coming-out dimensions and unprotected sexual behaviors were explained by psychological functioning. In particular, limited involvement in gay/lesbian activities was associated with more unprotected sex. Negative attitudes toward homosexuality were related directly to more unprotected sex, and they were related indirectly to more unprotected sex by means of increasing emotional distress. These and other findings have implications for designing preventive interventions to increase the youths' psychological functioning and reduce their unprotected sexual behaviors.     

The Collective Preference for Shared Information

Decision-making groups prefer to discuss shared information that all members know instead of unshared information that a single member knows. This bias toward discussing shared information can lead groups to make suboptimal decisions when unshared information is critical for good decision making. This preference for discussing shared information may stem from group members' positive evaluations of each other's task capabilities when shared information is communicated. Members who already are perceived as capable (i.e., those high in status, experts, and leaders) need not bolster their image by communicating shared information. Instead, they discuss unshared information more than members perceived as less capable. As members low in status gain respect by communicating shared information, they may risk mentioning unshared information later during discussion. Assigning group leaders, informing members of their expert roles, and allowing ample time for discussion may increase groups' discussion of unshared information.