Psychophysical scaling models of the form R = f, with R the response and I some intensity of an attribute, all assume that people judge the amounts of an attribute. With simple biases excepted, most also assume that judgments are independent of space, time, and features of the situation other than the one being judged. Many data support these ideas: Magnitude estimations of brightness increase with luminance. Nevertheless, I argue that the general model is wrong. The stabilized retinal (...) image literature shows that nothing is seen if light does not change over time. The classification literature shows that dimensions often combine to produce emergent properties that cannot be described by the elements in the stimulus. These and other effects cannot be adjusted for by simply adding variables to the general model because some factors do not combine linearly. The proposed alternative is that people initially judge the entire stimulus – the object in terms of its environment. This agrees with the constancy literature that shows that objects and their attributes are identified through their relations to other aspects of the scene. That the environment determines judgments is masked in scaling studies where the standard procedure is to hold context constant. In a typical brightness study the essential stimulus might be the intensity of the light or a difference between the light and the background. The two are perfectly confounded. This issue is examined in the case of audition. Judgments of the loudness of a tone depend on how much that tone differs from the previous tone in both pitch and loudness. To judge loudness people first seem to process the stimulus object in terms of differences between it and other aspects in the situation; only then do they assess the feature of interest. Psychophysical judgments will therefore be better interpreted by theories of attention that are based in biology or psychology than those that are based in classical physics. (shrink)

Psychophysical scales can be constructed under suitable restrictions from appropriate data, but they still do not justify privileged internal sensations.

People cannot make independent judgements of stimulus attributes and so (Lockhead 1992, p. 551) rather than in terms of stimulus features. The new commentaries here further this statement and also support the observations in the target article that psychophysical scaling methods allow us to measure (1) how context determines judgments and (2) what people remember about prior stimuli.

Traditionally, the investigation of truth has been anchored in a priori reasoning. Cognitive science deviates from this tradition by adding empirical data on how people understand and use concepts. Building on psychophysics and machine learning methods, we introduce conceptual scaling, an approach to map people's understanding of abstract concepts. This approach, allows computing participant-specific conceptual maps from obtained ordinal comparison data, thereby quantifying perceived similarities among abstract concepts. Using this approach, we investigated individual's alignment with philosophical theories on truth (...) and the predictive capacity of conceptual maps. The obtained results indicated that, while people's understanding of truth is multifaceted and encapsulates notions of coherence and authenticity, alignment is best for the correspondence theory of truth. Furthermore, conceptual maps allowed predicting individual outcomes with an accuracy of roughly 70%. This research demonstrates that conceptual scaling offers accurate descriptions of individual's understanding of abstract concepts, behavioral predictions, and quantification of alignment with theoretical perspectives. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Psychophysical Causation and a Pragmatist Approach to Human BehaviorDavid H. Brendel (bio)Keywordsmind-body problem, philosophy, pragmatism, psychology, psychophysical causationJochen Fahrenberg and Marcus Cheetham have performed a valuable service by conducting and presenting an empirical study of some basic philosophical assumptions of psychologists, philosophers, and scientists. Well-designed, large-scale empirical studies of this kind are all too rare in the literature. Those of us interested in the human sciences are (...) rather in the dark about the assumptions of others working in our own and related fields. For the most part, we are privy only to the philosophical assumptions of friends and colleagues we know intimately and of those relative few who publish their views. We can only speculate about the views of the countless others with whom we have not had the opportunity to establish direct philosophical discourse. The findings presented by Fahrenberg and Cheetham give us an intriguing glimpse at some of the key philosophical assumptions of a variety of clinicians and academics who are interested in human nature and the human sciences.My aim in this commentary is to present an interpretation of a central finding of this questionnaire study: that psychologists were more likely than philosophers and scientists to embrace “psychophysical causation” as a part of their philosophical worldview. It is not, I think, too much of an oversimplification to define psychophysical causation as the presumption that mental events and physical events can cause other mental events and physical events. Psychophysical causation can be distinguished from other positions on the mind–body relation, some of which Fahrenberg and Cheetham mention in their article. Among these alternative positions is epiphenomenalism, the position that physical events cause other physical events and can cause mental events, but that mental events themselves have no causal power. Another philosophical position distinct from psychophysical causation is monism, which holds that all events in the world in general (and in human beings in particular) are physical and are best described in physical terms. Fahrenberg and Cheetham do not describe the multiple forms of monism in detail, but it is worth noting that reductive materialism (Wilson 1998) and eliminative materialism (Churchland 1981) are two highly developed forms of the kind of monism to which they allude. It is beyond the scope of this commentary to explore the differences between the two, but suffice it to say that both these forms of materialism reject the legitimacy of mental [End Page 205] events or the mental vocabulary that refers to such events.It is also beyond the scope of this commentary to advance arguments either for or against psychophysical causation in the philosophy of mind. The concept of psychophysical causation certainly has multiple proponents among philosophers, including those who are ontological monists. The compelling nonreductive materialism of a philosopher such as Terence Horgan, for example, suggests the viability of combining ontological monism with methodological pluralism. In a book chapter entitled “Nonreductive Materialism and the Explanatory Autonomy of Psychology,” Horgan (1993) developed the position that the world is entirely physical (i.e., there are no disembodied minds, persons, or other entities) but is so complex that it can only be understood and explained by employing many vocabularies and methodologies, spanning “the microphysical, neurobiological, macrobiological, and psychological.” This kind of methodological pluralism in the philosophy of mind can be disputed on conceptual grounds, but it seems to be at least as justifiable (and perhaps more justifiable) when compared with other well-defined positions on the mind–body relation.The appeal of nonreductive materialism and psychophysical causation comes into particularly clear focus in contexts where our philosophical concerns are pragmatic in nature. In other words, when we need to achieve practical goals in our everyday lives, we usually benefit from a philosophy that provides us with the flexibility to use a broad range of ideas, conceptual tools, and causal hypotheses that can be adapted to specific needs and challenges. Nonreductive materialism regards the world as a purely physical place, but ensures this kind of conceptual and methodological flexibility when it comes to explaining and predicting complex human experience and behavior. “Typically, certain context-relative features of discourse,” Horgan wrote (1993, 298), “will determine, in a given... (shrink)

Psychophysics measures the attributes of perceptual experience. The question of whether some of these attributes should be interpreted as more fundamental, or “real,” than others has been answered differently throughout its history. The operationism of Stevens and Boring answers “no,” reacting to the perceived vacuity of earlier debates about fundamentality. The subsequent rise of multidimensional scaling (MDS) implicitly answers “yes” in its insistence that psychophysical data be represented in spaces of low dimensionality. I argue the return of fundamentality (...) follows from a trend toward increasing epistemic humility. Operationism exhibited a kind of hubris in the constitutive role it assigned to the experimenter’s presuppositions that is abandoned by the algorithmic methods of MDS. This broad epistemic trend is illustrated by following the trajectory of research on a particular candidate attribute: tonal volume. (shrink)

Two experiments were conducted for the derivation of psychophysical scales of the following audio descriptors: spectral centroid, spectral spread, spectral skewness, odd-to-even harmonic ratio, spectral deviation, and spectral slope. The stimulus sets of each audio descriptor were synthesized and independently controlled through appropriate synthesis techniques. Partition scaling methods were used in both experiments, and the scales were constructed by fitting well-behaving functions to the listeners' ratings. In the first experiment, the listeners' task was the estimation of the relative (...) differences between successive levels of a particular audio descriptor. The median values of listeners' ratings increased with increasing feature values, which confirmed listeners' abilities to estimate intervals. However, there was a large variability in the reliability of the derived interval scales depending on the stimulus spacing in each trial. In the second experiment, listeners had control over the stimulus values and were asked to divide the presented range of values into perceptually equal intervals, which provides a ratio scale. For every descriptor, the reliability of the derived ratio scales was excellent. The unit of a particular ratio scale was assigned empirically so as to facilitate qualitative comparisons between the scales of all audio descriptors. The construction of psychophysical scales based on univariate stimuli allowed for the establishment of cause-and-effect relations between audio descriptors and perceptual dimensions, contrary to past research that has relied on multivariate stimuli and has only examined the correlations between the two. Most importantly, this study provides an understanding of the ways in which the sensation magnitudes of several audio descriptors are apprehended. (shrink)

In the present paper the relation between objective and subjective time is studied from a neutral non-dualist perspective Adoption of the relational concept of time leads to fundamental problems of time measurement of the uniformity of time measures, and of a native measure of duration in subjective experience. Experimental data on discrimination and reproduction of time intervals are reviewed and relevant models of internal time representations are discussed. Special attention is given to the 'dual klepsydra model' (DKM)and to the outstanding (...) properties of the reproduction func- tion yielded by the DKM Time scales generated by a DKM-based reproduction mechanisms are studied It is shown that such 'klepsydraic clocks' generate time measures which are non-uniform with respect to objective time yet internally consistent within an ensemble of such clocks and in this sense 'quasi-uniform' . Competing concepts of subjective time and modeling principles of internal time representation are briefly discussed Some interesting parallels be- tween our psychophysical approach and E.A. Milne's treatment of the problem of uniform time are drawn in the Appendix. (shrink)

The sense of agency is a subjective feeling that one's own actions drive action outcomes. Previous studies have focused primarily on the temporal contingency between actions and sensory inputs as a possible mechanism for the sense of agency. However, the contribution of the integrity of visual inputs has not been systematically addressed. In the current study, we developed a psychophysical task to examine the role of visual inputs as well as temporal contingencies toward the sense of agency. Specifically, participants (...) were required to track a target on a sinusoidal curve on a computer screen. Visual integrity of sensory inputs was manipulated by gradually occluding a computer cursor, and participants were asked to report the sense of agency on a nine-point Likert scale. Temporal contingency was manipulated by varying the delay between finger movements on a touchpad and cursor movements. The results showed that the sense of agency was influenced by both visual integrity and temporal contingency. These results are discussed in the context of current models that have proposed that the sense of agency emerges from the comparison of visual inputs with motor commands. (shrink)

In contrast to Lockhead's view it is argued that psychology as a genuine science must not be based on other sciences and that psychological measurements have to be validated inside psychology. It is pointed out that psychological scalings, unaffected by judgment contexts, can be obtained if the experimental setting is compatible with everyday situations.

Previous studies have demonstrated that orientation-specific deprivation in early life can lead to neural deficits of spatial vision in certain space, and can even result in meridional amblyopia. Individuals with astigmatism are the optimal and natural models for exploring this asymmetric development of spatial vision in the human visual system. This study aims to assess the contrast sensitivity function and EEG signals along two principal meridians in participants with regular astigmatism when being optimal optical corrected. Twelve participants with astigmatism and (...) thirteen participants with were recruited in the current study. CSFs and spatial sweep visual evoked potentials were measured with vertical and horizontal sinewave gratings along two principal meridians monocularly. Area under log CSF, spatial frequency threshold corresponding to 80% contrast gratings, and CSF acuity were calculated from CSF test. In addition, sVEP amplitudes and thresholds were calculated with the recursive least square method. Participants with astigmatism exhibited marked vertical-horizontal resolution disparities even after they were corrected with optimal optical corrections. CSF tests showed that AULCSF along weak meridian was lower than that along strong meridian in both groups. Significant meridional disparity of CSF acuity was also found in both groups. In addition, the MA group showed larger meridional disparity compared to the AST group. Spatial sVEP thresholds also supported the existence of marked meridional disparity. Our results suggest that meridian-specific partial deprivation in early life might lead to monocularly asymmetric development of spatial vision in the human visual system. In terms of application, we tested the feasibility and reliability of adopting psychophysical and EEG scalings to investigate the asymmetric development of spatial vision related to astigmatism. These paradigms are potentially applicable to reduce and even eliminate the meridional disparity in the primary visual cortex by adopting perceptual learning or other vision-related interventions. (shrink)

Our families are our first and most important ethical training grounds. But what is the family? And what are our ethical commitments to our family members and to the broader moral community? After a brief introductory chapter on basic ethical concepts and theories, the essays in this volume provide readers with ethical analyses of issues ranging from same-sex marriage to a controversial proposal to "license" parents. The chapters cover love, sex, marriage, parents and children, the relationship between the family and (...) the larger moral community, and the influence of emerging technologies on the ethical issues inherent in family life. The volume is intended to open up this exciting territory in applied ethics to those interested in philosophy, family studies, social work, and to anyone who wants a deeper understanding of the ethical forces at work in this most basic social institution. (shrink)