The development of young infants' intuitions about support

Previous research has shown that 3-month-old infants, like adults, expect a box to be stable when it is in full contact with a platform, and to fall when it loses all contact with the platform. Do young infants also have expectations about what should happen when the box is only in partial contact with the platform? The present research was designed to address this question. In Experiment 1, 6.5-month-old infants saw two test events: a full-contact and a partial-contact test event. In both events, the infants watched the extended finger of a gloved hand push a box along the top of a platform. In the full-contact event, the box was pushed until its leading edge reached the end of the platform. In the partial-contact event, the box was pushed until only 15% or 70% of its bottom surface remained on the platform. The infants looked reliably longer at the partial-than at the full-contact event when 15%, but not 70%, of the box rested on the platform. These results suggested that the infants were able to judge how much contact was needed between the box and the platform for the box to be stable. A control condition provided evidence for this interpretation. In Experiment 2, 5.5- to 6-month-old infants were found to look equally at the full- and the partial-contact events, even when only 15% of the box's bottom surface remained on the platform. This result suggested that prior to 6.5 months of age infants perceive any amount of contact between the box and the platform to be sufficient to ensure the box's stability. Interpretations of this developmental sequence are considered in the Conclusion.     

Evaluating the mind's eye: the metacognition of visual imagery

Can people evaluate phenomenal qualities of internally generated experiences, such as whether a mental image is vivid or detailed? This question exemplifies a problem of metacognition: How well do people know their own thoughts? In the study reported here, participants were instructed to imagine a specific visual pattern and rate its vividness, after which they were presented with an ambiguous rivalry display that consisted of the previously imagined pattern plus an orthogonal pattern. On individual trials, higher ratings of vividness predicted a greater likelihood that the imagined pattern would appear dominant when the participant was subsequently presented with the binocular rivalry display. Off-line self-report questionnaires measuring imagery vividness also predicted individual differences in the strength of imagery bias over the entire study. Perceptual bias due to mental imagery could not be attributed to demand characteristics, as no bias was observed on catch-trial presentations of mock rivalry displays. Our findings provide novel evidence that people have a good metacognitive understanding of their own mental imagery and can reliably evaluate the vividness of single episodes of imagination.     

Acquiring new spatial intuitions: learning to reason about rotations

There are certain simple rotations of objects that most people cannot reason about accurately. Reliable gaps in the understanding of a fundamental physical domain raise the question of how learning to reason in that domain might proceed. Using virtual reality techniques, this project investigated the nature of learning to reason across the domain of simple rotations. Learning consisted of the acquisition of spatial intuitions: there was encoding of useful spatiotemporal information in specific problem types and a gradual accumulation of this understanding across the domain. This pattern of learning through the accumulation of intuitions is especially interesting for rotational motion, in which an elegant domain-wide kinematics is available to support insightful learning. Individual ability to reason about rotations correlated highly with mastery motivation, skill in fluid reasoning, and skill in reasoning about spatial transformations. Thus, general cognitive advantages aided the understanding of individual rotations without guaranteeing immediate generalization across the domain.     

Empirical metaphysics: the role of intuitions about possible cases in philosophy

Frank Jackson has argued that only if we have a priori knowledge of the extension-fixers for many of our terms can we vindicate the methodological practice of relying on intuitions to decide between philosophical theories. While there has been much discussion of Jackson’s claim that we have such knowledge, there has been comparatively little discussion of this most powerful argument for that claim. Here I defend an alternative explanation of our intuitions about possible cases, one that does not rely on a priori extension-fixers. This alternative explanation provides a vindication of our reliance on intuitions, while blocking Jackson’s abductive argument for a priori semantic knowledge. In brief, I argue that we should regard our armchair intuitions as providing an important, a priori source of evidence for hypotheses about the contents of our implicit referential policies with regard to our terms. But all such hypotheses have a potential falsifier that is only discoverable empirically. In other words, gold-standard evidence for such hypotheses is always empirical.

The pre-theoreticality of moral intuitions

Moral intuitionism, once an apparently moribund metaethical position, has seen a resurgence of interest of late. Robert Audi, a leading moral intuitionist, has argued that in order for a moral belief to qualify as intuitional, it must fulfill four criteria: it must be non-inferential, firmly held, comprehended, and pre-theoretical. This paper centers on the fourth and seemingly most problematic criterion: pre-theoreticality. The paper begins by stipulating the defensibility of the moral cognitivism upon which moral intuitionism turns. Next, the paper develops the distinction between semantic and epistemic pre-theoreticality, and goes on to explore and reject the putative ubiquity of the theoreticality of first-order moral discourse: it argues that on a defensible understanding of theoryhood, both semantic and epistemic pre-theoretical moral belief is not only possible, but in fact frequently realized. The paper then briefly explores and rebuts objections to (epistemic) pre-theoreticality issuing from (i) the “Cornell Realists” and (ii) considerations of the epistemic relevance of the epistemic/valuational background of moral belief. The paper concludes that, so far as the pre-theoreticality criterion is concerned, moral intuitionism remains in the running as a viable thesis regarding foundationally justified first-order moral belief and knowledge.     

Measurement of visual aftereffects and inferences about binocular mechanisms in human vision

There is conflicting evidence concerning the characteristics of binocular channels in the human visual system with respect to the existence of a 'pure' binocular channel that responds only to simultaneous stimulation of both eyes. Four experiments were conducted to resolve these discrepancies and to evaluate the evidence for the existence of such an exclusive binocular channel. In the first three studies, tilt aftereffects were measured after monocular adaptation. The relative sizes of the direct, interocularly transferred, and binocular aftereffects were not influenced by the configuration of the adapting pattern (experiment 1), or by the eye used for adaptation (experiment 2). There were also consistent interobserver differences in the relative sizes of the aftereffect seen after monocular adaptation (experiment 3). Taken together, these data raise questions about the appropriateness of a monocular adaptation paradigm for evaluating the presence of a pure binocular channel in observers with normal binocular vision. In experiment 4, in which the paradigm of alternating monocular adaptation was used, data were obtained that are consistent with the presence of a pure binocular channel.     

Development of infants’ intuitions about support relations: sensitivity to stability

Can infants perceive stability when a supported box is put on a supporting box in a balanced position? In Experiment 1, 41 infants saw three events. In a stable event, the supported box was put on a wide supporting box in a balanced position. In an unstable event, the supported box was put on a narrow supporting box in a balanced position. In an impossible event, the supported box was put on the extreme end of a wide supporting box. Infants 4 to 6.5 months old looked equally at all three events. Infants 6.5 to 10 months old looked slightly longer at the impossible event than at the other events. Infants 10 to 13 months old looked reliably longer at the unstable and impossible events than at the stable event. The results of Experiment 2 indicate that these differences in looking times did not come from differences in stimulus configurations between the events. These results suggest that infants above 10 months old are sensitive to stability of support relations.     

The persistence of a misconception about vision after educational interventions

Children and adults, like many ancient philosophers, believe that seeing involves emissions from the eye. Several experiments tested the strength of these “extramission” beliefs to determine whether they, like other scientific misconceptions, are resistant to educational experiences. Traditional college-level education had little impact. Presenting a simplified lesson, stressing visual input, and a lesson directly counteracting the vision misconception had an impact, but for older participants the effect was evident only on short-term tests. Despite some gain due to learning, overall the results demonstrated the robustness of extramission beliefs.     

Caffeine consumption questionnaire: a standardized measure for caffeine consumption in undergraduate students

Undergraduate students (N=691) were given the 1992 Caffeine Consumption Questionnaire of Landrum and provided information on age, sex, and year in school. A subset (n = 168) of those completing the questionnaire were also given the Morningness-Eveningness Questionnaire of Horne and Ostberg. Analysis indicated that the average intake of caffeine was roughly 1,600 mg, i.e., a range from 13 mg to 21,840 mg per week. Older students consumed more caffeine than younger ones, and students with an Evening personality preference consumed more caffeine in the evening and nighttime hours than those with a Morning personality preference. These results are discussed in the context of other caffeine studies. Caffeine consumption is an important issue, and a consistent measurement system should be used by various researchers testing different populations.     

Individual differences in achieving tendency: Review of evidence bearing on a questionnaire measure

The Mehrabian Achieving Tendency Scale (MATS) provides a broad-scoped assessment of individual characteristics associated with achievement. The MATS is highly reliable and reasonably free of response bias. It correlated negatively with various measures of general (trait) anxiety and fear of success. The MATS successfully predicted performance in situations approximating real-life tests of work and school performance and academic attitudes (e.g., level of aspiration, interest and satisfaction, leadership and initiative). The MATS also predicted occupational choice and occupational/organizational commitment and attractive/appropriate self-presentation. Within a general model of personality and temperament, the MATS was shown to consist primarily of trait dominance and secondarily of trait pleasure. The model successfully predicted relationships of the MATS with a variety of personality measures.     

Development of a questionnaire to measure concern for dental appearance.

100 adults, selected for cosmetic dental treatment in a general dental practice, completed a 42-item questionnaire designed, on the basis of previous research and the author's clinical experience, to measure concern for dental appearance. This had high internal consistency and was reduced to a questionnaire of 23 items with internal consistency shown by a standardised Cronbach alpha of .84. An exploratory factor analysis with varimax rotation identified six factors, the main one appearing to be a measure of concern for dental appearance. The high internal consistency suggests that the total score for the revised questionnaire is a measure of a construct, concern for dental appearance. Although the simplest measure of that may be contained in the items for the first factor, a much larger sample would be necessary to confirm the complex factor structure and so the questionnaire's total score is probably the more reliable measure at present. A study is summarised showing that the total score provides a measure that, in statistical regression analysis, may predict the intentions of adults to take care of the appearance of their teeth.     

The importance of a visual horizon for distance judgments under severely degraded vision

In two experiments we examined the role of visual horizon information on absolute egocentric distance judgments to on-ground targets. Sedgwick [1983, in Human and Machine Vision (New York: Academic Press) pp 425-458] suggested that the visual system may utilize the angle of declination from a horizontal line of sight to the target location (horizon distance relation) to determine absolute distances on infinite ground surfaces. While studies have supported this hypothesis, less is known about the specific cues (vestibular, visual) used to determine horizontal line of sight. We investigated this question by requiring observers to judge distances under degraded vision given an unaltered or raised visual horizon. The results suggest that visual horizon information does influence perception of absolute distances as evident through two different action-based measures: walking or throwing without vision to previously viewed targets. Distances were judged as shorter in the presence of a raised visual horizon. The results are discussed with respect to how the visual system accurately determines absolute distance to objects on a finite ground plane and for their implications for understanding space perception in low-vision individuals.     

Initial psychometric properties of the experiences questionnaire: validation of a self-report measure of decentering

Decentering is defined as the ability to observe one's thoughts and feelings as temporary, objective events in the mind, as opposed to reflections of the self that are necessarily true. The Experiences Questionnaire (EQ) was designed to measure both decentering and rumination but has not been empirically validated. The current study investigated the factor structure of the EQ in both undergraduate and clinical populations. A single, unifactorial decentering construct emerged using 2 undergraduate samples. The convergent and discriminant validity of this decentering factor was demonstrated in negative relationships with measures of depression symptoms, depressive rumination, experiential avoidance, and emotion regulation. Finally, the factor structure of the EQ was replicated in a clinical sample of individuals in remission from depression, and the decentering factor evidenced a negative relationship to concurrent levels of depression symptoms. Findings from this series of studies offer initial support for the EQ as a measure of decentering.     

The reliability of moral intuitions: A challenge from neuroscience

A recent study of moral intuitions, performed by Joshua Greene and a group of researchers at Princeton University, has recently received a lot of attention. Greene and his collaborators designed a set of experiments in which subjects were undergoing brain scanning as they were asked to respond to various practical dilemmas. They found that contemplation of some of these cases (cases where the subjects had to imagine that they must use some direct form of violence) elicited greater activity in certain areas of the brain associated with emotions compared with the other cases. It has been argued (e.g., by Peter Singer) that these results undermine the reliability of our moral intuitions, and therefore provide an objection to methods of moral reasoning that presuppose that they carry an evidential weight (such as the idea of reflective equilibrium). I distinguish between two ways in which Greene's findings lend support for a sceptical attitude towards intuitions. I argue that, given the first version of the challenge, the method of reflective equilibrium can easily accommodate the findings. As for the second version of the challenge, I argue that it does not so much pose a threat specifically to the method of reflective equilibrium but to the idea that moral claims can be justified through rational argumentation in general.