Action is a means of acquiring perceptual information about the environment. Turning around, for example, alters your spatial relations to surrounding objects and, hence, which of their properties you visually perceive. Moving your hand over an object’s surface enables you to feel its shape, temperature, and texture. Sniffing and walking around a room enables you to track down the source of an unpleasant smell. Active or passive movements of the body can also generate useful sources of perceptual information (Gibson 1966, (...) 1979). The pattern of optic flow in the retinal image produced by forward locomotion, for example, contains information about the direction in which you are heading, while motion parallax is a “cue” used by the visual system to estimate the relative distances of objects in your field of view. In these uncontroversial ways and others, perception is instrumentally dependent on action. According to an explanatory framework that Susan Hurley (1998) dubs the “Input-Output Picture”, the dependence of perception on action is purely instrumental: "Movement can alter sensory inputs and so result in different perceptions… changes in output are merely a means to changes in input, on which perception depends directly" (1998: 342). -/- The action-based theories of perception, reviewed in this entry, challenge the Input-Output Picture. They maintain that perception can also depend in a noninstrumental or constitutive way on action (or, more generally, on capacities for object-directed motor control). This position has taken many different forms in the history of philosophy and psychology. Most action-based theories of perception in the last 300 years, however, have looked to action in order to explain how vision, in particular, acquires either all or some of its spatial representational content. Accordingly, these are the theories on which we shall focus here. -/- We begin in Section 1 by discussing George Berkeley’s Towards a New Theory of Vision (1709), the historical locus classicus of action-based theories of perception, and one of the most influential texts on vision ever written. Berkeley argues that the basic or “proper” deliverance of vision is not an arrangement of voluminous objects in three-dimensional space, but rather a two-dimensional manifold of light and color. We then turn to a discussion of Lotze, Helmholtz, and the local sign doctrine. The “local signs” were felt cues for the mind to know what sort of spatial content to imbue visual experience with. For Lotze, these cues were “inflowing” kinaesthetic feelings that result from actually moving the eyes, while, for Helmholtz, they were “outflowing” motor commands sent to move the eyes. -/- In Section 2, we discuss sensorimotor contingency theories, which became prominent in the 20thcentury. These views maintain that an ability to predict the sensory consequences of self-initiated actions is necessary for perception. Among the motivations for this family of theories is the problem of visual direction constancy—why do objects appear to be stationary even though the locations on the retina to which they reflect light change with every eye movement?—as well as experiments on adaptation to optical rearrangement devices (ORDs) and sensory substitution. -/- Section 3 examines two other important 20th century theories. According to what we shall call the motor component theory, efference copies generated in the oculomotor system and/or proprioceptive feedback from eye-movements are used together with incoming sensory inputs to determine the spatial attributes of perceived objects. Efferent readiness theories, by contrast, look to the particular ways in which perceptual states prepare the observer to move and act in relation to the environment. The modest readiness theory, as we shall call it, claims that the way an object’s spatial attributes are represented in visual experience can be modulated by one or another form of covert action planning. The bold readiness theory argues for the stronger claim that perception just is covert readiness for action. -/- In Section 4, we move to the disposition theory, most influentially articulated by Gareth Evans (1982, 1985), but more recently defended by Rick Grush (2000, 2007). Evans’ theory is, at its core, very similar to the bold efferent readiness theory. There are some notable differences, though. Evans’ account is more finely articulated in some philosophical respects. It also does not posit a reduction of perception to behavioral dispositions, but rather posits that certain complicated relations between perceptual input and behavioral provide spatial content. Grush proposes a very specific theory that is like Evans’ in that it does not posit a reduction, but unlike Evans’ view, does not put behavioral dispositions and sensory input on an undifferentiated footing. (shrink)

Visual percepts frequently appear chromatically rich, yet their paucity in reportable information has led to widely accepted minimalist models of vision. The discrepancy may be resolved by positing that the richness of natural scenes is reflected in phenomenal consciousness but not in detail in the phenomenal judgments upon which reports about qualia are based. Conceptual awareness (including phenomenal judgments) arises from neural mechanisms that categorize objects, and also from mechanisms that conceptually characterize textural properties of pre-categorically segmented regions in the (...) visual field. Experimental evidence suggests that complex images instigate the generation of so-called ensemble phenomenal judgments. These involve concepts that categorize global attributes of segmented areas but carry no information pertaining to details. It is then argued that there are cogent reasons for believing that phenomenal percepts (i.e. qualia) arising from chromatically complex stimuli cohere in this ensemble sense with both the stimulus and with the resulting ensemble phenomenal judgments. Thus, spatially detailed retinal images are deemed to yield correspondingly detailed phenomenal experiences that are in turn conceptually apprehended via a relatively small number of ensemble phenomenal judgments. Lastly, it is suggested that the bridge locus for chromatically rich phenomenal experiences is most plausibly located early in the cortical visual pathway. (shrink)

Rotter’s theory of internal-external locus of control evolved from Carl Jung’s work. In Psychological Types (1923), Jung defined two opposing tendencies in personality introversion and extroversion. While both tendencies are present in all individuals, one tends to dominate the other. The internal–external control construct was conceived as a generalized expectancy to perceive reinforcement either as contingent upon one’s own behaviors (internal control) or as the result of forces beyond one’s control, such as chance, fate, or powerful others (external control) (...) (Lefcourt, 1981, p. 15). Locus of control refers to those causes to which individuals attribute their successes and failures. Individuals are responsive to some external motivators (e.g. better jobs, promotions, higher salaries), but the more powerful are internal pressures (the desire for increased job satisfaction, self-esteem, and quality of life). Research indicates that an individual’s internal–external locus of control impacts their ethical behavior in an organization. Rotter’s I–E Scale (1966, Psychological Monographics 80(1), 1–28), a 29 item forced choice instrument, is the most widely used instrument to measure the degree of internality versus externality. Each respondent’s score for this scale had a potential range from 0 to 23. As there are six filler items used to mask the intent of the questionnaire a score of 23 being extremely external in nature and a score of zero being extremely internal in nature. The I Scale (Internal Scale) measures the extent to which people believe that they have control over their own lives; the E Scale (External Scale) measures the extent to which people believe that they do not have control over their own lives. This study utilized the I–E Scale. Jones (Unpublished Doctoral Dissertation) and Deflumeri (Unpublished Doctoral Dissertation) investigated the likelihood of an individual to engage in unethical behavior in an organization. This research suggests that when employees perceive that locus of control resides internally they themselves decide what is appropriate behavior, but with an external locus of control, employees will look at others to decide appropriate behavior. The researcher in this study investigated the relationship between managers’ locus of control and their moral reasoning. (shrink)

According to an influential philosophical view I call “the relational properties view”, “perspectival” properties, such as the elliptical appearance of a tilted coin, are relational properties of external objects. Philosophers have assessed this view on the basis of phenomenological, epistemological or other purely philosophical considerations. My aim in this paper is to examine whether it is possible to evaluate RPV empirically. In the first, negative part of the paper I consider and reject a certain tempting way of doing so. In (...) the second, positive part of the paper I suggest a novel way of evaluating RPV empirically, relying on the influential object files framework. (shrink)

How does neuronal activity give rise to cognitive capacities? To address this question, neuroscientists hypothesize about what neurons “represent,” “encode,” or “compute,” and test these hypotheses empirically. This process is similar to the assessment of hypotheses in other fields of science and as such is subject to the same limitations and difficulties that have been discussed at length by philosophers of science. In this paper, we highlight an additional difficulty in the process of empirical assessment of hypotheses that is unique (...) to the cognitive sciences. We argue that, unlike in other scientific fields, comparing hypotheses according to the extent to which they explain or predict empirical data can lead to absurd results. Other considerations, which are perhaps more subjective, must be taken into account. We focus on one such consideration, which is the purposeful function of the neurons as part of a biological system. We believe that progress in neuroscience critically depends on properly addressing this difficulty. (shrink)

The myside bias in written argumentation entails excluding other side information from essays. To determine the locus of the bias, 86 Experiment 1 participants were assigned to argue either for or against their preferred side of a proposal. Participants were given either balanced or unrestricted research instructions. Balanced research instructions significantly increased the use of other side information. Participants' notes, rather than search patterns, predicted the myside bias. Participants who defined good arguments as those that can be “proved by (...) facts” were more prone towards the myside bias. In Experiment 2, 84 participants of high and low argumentation ability read a text called “More Than Just the Facts” designed to contradict this fact-based argumentation schema. For high argumentation ability participants, the intervention reduced the myside bias, but for low ability participants it increased. The roots of the myside bias are underdeveloped argumentation schemata leading to misconceptions about research and argumentation. (shrink)

A judge springs out of his car on the way to court in downtown Chicago and takes photographs of an inflatable rat. A while later he inserts these photographs into a decision involving another inflatable rodent. Judges now regularly insert pictures in judgments, but there is no study either of the genres or the precedential status of these modern visual emblemata, these pictorial interventions in the record. Using a comparative visual corpus of over three hundred images extracted from diverse common (...) law jurisdictions, the practice of retinal justice, the novelty of vision in decision, is here anatomized, choreographed, and critically classified. (shrink)

Twelve subjects provided shape and orientation judgments for a set of projectively equivalent, variously rotated rectangles under three viewing conditions—monoptic, dichoptic, and binocular—with and without the presence of a pattern mask. In the absence of the mask, partial constancy was exhibited under the first two conditions and near perfect constancy under the binocular condition. Orientation was discriminated. Presence of the mask produced projective shape matching and diminished orientation discrimination. It is argued that the site of masking was postchiasmal, and the (...) results are related to previous work with pattern masking of projectively equivalent ellipses. (shrink)

Grammatical markers are not uniformly impaired across speakers of different languages, even when speakers share a diagnosis and the marker in question is grammaticalized in a similar way in these languages. The aim of this work is to demarcate, from a cross-linguistic perspective, the linguistic phenotype of three genetically heterogeneous developmental disorders: specific language impairment, Down syndrome, and autism spectrum disorder. After a systematic review of linguistic profiles targeting mainly English-, Greek-, Catalan-, and Spanish-speaking populations with developmental disorders (n = (...) 880), shared loci of impairment are identified and certain domains of grammar are shown to be more vulnerable than others. The distribution of impaired loci is captured by the Locus Preservation Hypothesis which suggests that specific parts of the language faculty are immune to impairment across developmental disorders. Through the Locus Preservation Hypothesis, a classical chicken and egg question can be addressed: Do poor conceptual resources and memory limitations result in an atypical grammar or does a grammatical breakdown lead to conceptual and memory limitations? Overall, certain morphological markers reveal themselves as highly susceptible to impairment, while syntactic operations are preserved, granting support to the first scenario. The origin of resilient syntax is explained from a phylogenetic perspective in connection to the “syntax-before-phonology” hypothesis. (shrink)

It may be possible, one day, to use gene therapy to treat diseases whose genetic defects have been discerned. Because many genes responsible for inherited eye disorders within the retina have been identified, diseases of the eye are prime candidates for this form of therapy. The eye also has the advantage of being highly accessible with altered immunological properties, important considerations for easy delivery of virus and avoidance of systemic immune responses. Currently, adenovirus, adeno‐associated virus and lentivirus have been used (...) to successfully transfer genetic material to retinal pigment epithelium and photoreceptor cells. By harnessing therapeutic genes to these viruses, researchers have been able to demonstrate rescue in rodent models of retinitis pigmentosa, providing evidence that this form of therapy can be effective in delaying photoreceptor cell death. Future challenges include confirming therapeutic effects in animal models with eyes more anatomically similar to those of humans and demonstrating long‐term rescue with minimal toxicity. BioEssays 23:662–668, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

Between‐trial effects in Stroop‐like interference tasks are linked to differences in the amount of cognitive control. Trials following an incongruent trial show less interference, an effect suggested to result from the increased control caused by the incongruent previous trial (known as the Gratton effect). In this study, we show that cognitive control not only results in a different amount of interference but also in a different locus of the interference. That is, the stage of the task that shows the (...) most interference changes as a function of the preceding trial. Using computational cognitive modeling, we explain these effects by a difference in the amount of processing of the irrelevant dimension of the stimulus. (shrink)

Locus equations contain an economical set of hidden (i.e., not directly observable in the data) parameters of speech that provide an elegant way of characterizing the ubiquitous context-dependent behaviors exhibited in speech acoustics. These hidden parameters can be effectively exploited to constrain the huge set of context-dependent speech model parameters currently in use in modern, mainstream speech recognition technology.

This paper examines the semantics and the narrative function of Calypso’s island, which can be understood as a locus amoenus. The description moves from the inner cave of a lovely nymph outward to the surroundings of the seductive landscape. Hermes’ pleasure at the scene stands in contrast to the disinterested attitude of Odysseus weeping on the shore, which anticipates his rejection of the nymph. The connections between this scene and the weeping Achilles looking out over the sea in a (...) similar setting further define this contrast as a central theme of the Calypso episode. The semantics of the locus amoenus in Od. 5 is paralleled by the Sirens’ meadow, which stands in juxtaposition with their seductive voice. (shrink)

Evaluating the current locus equation under ideal conditions identifies important and unexpected parameter dependencies. Locus equation (LE) utility, either as a valid laboratory tool or possible invariant cue, depends on stringent specification of critical parameters and rigorous empirical testing.

Sensorimotor theorists of perception have argued that eye movement is a necessary condition for seeing on the basis that subjects whose retinal images do not move undergo a form of blindness. I show that the argument does not work.

This article examines Gerald Odonis' view on the nature of place as found in his commentary on the Sentences (Sent. II, d. 2, qq. 3-5) and in an anonymous question (Utrum locus sit ultima superficies corporis ambientis immobile primum) extant in manuscript Madrid, Biblioteca Nacional, 4229. Both texts defend a thoroughly un-Aristotelian conception of place as three-dimensional space. Odonis not only deviates from Aristotle's definition of place as the inner surface of a surrounding body, but also from the positions (...) of his contemporaries, including fellow Franciscans. Despite some remarkable doctrinal similarities between Odonis' view and that of Renaissance innovators like Francesco Patrizi and Bernardino Telesio, it seems unlikely that Gerald played a role in the rise of new conceptions of place in the sixteenth and seventeenth century. An edition of the anonymous Quaestio de loco is given in an appendix. (shrink)

In their important work on locus equations, Sussman and his colleagues have helped to simplify the theoretical problem of how human listeners identify place of articulation contrasts among consonants, but much work remains before this problem is solved.

ABSTRACTThis study aimed to investigate the association of locus of control with reading and mathematics achievement of high school students with disabilities using data from the Special Educ...

The potential role of locus equations in three existing models of human classification behavior is examined. Locus equations can play a useful role in single-prototype and boundary-based models for human consonant recognition by reducing model complexity.