Subliminal priming of actions influences sense of control over effects of action

The experience of controlling one’s own actions, and through them events in the outside world, is a pervasive feature of human mental life. Two experiments investigated the relation between this sense of control and the internal processes involved in action selection and cognitive control. Action selection was manipulated by subliminally priming left or right keypress actions in response to a supraliminal visual target. The action caused the display of one of several colours as an action effect. The specific colour shown depended on whether the participant’s action was compatible or incompatible with the preceding subliminal prime, and not on the prime identity alone. Unlike previous studies, therefore, the primes did not predict the to-be-expected action effects. Participants rated how much control they experienced over the different colours. Replicating previous results, compatible primes facilitated responding, whereas incompatible primes interfered with response selection. Crucially, priming also modulated the sense of control over action effects: participants experienced more control over colours produced by actions that were compatible with the preceding prime than over colours associated with prime-incompatible actions. Experiment 2 showed that this effect was not solely due to priming modulating action–effect contingencies. These results suggest that sense of control is linked to processes of selection between alternative actions, being strongest when selection is smooth and uncontested.     

What do rats learn about the geometry of object arrays? Tests with exploratory behavior

Six experiments using habituation of exploratory behavior tested whether disoriented rats foraging in a large arena encode the shapes of arrays of objects. Rats did not respond to changes in position of a single object, but they responded to a change in object color and to a change in position of 1 object in a square array, as in previous research (e.g., C. Thinus-Blanc et al., 1987). Rats also responded to an expansion of a square array, suggesting that they encoded sets of interobject distances rather than overall shape. In Experiments 4-6, rats did not respond to changes in sense of a triangular array that maintained interobject distances and angles. Shapes of object arrays are encoded differently from shapes of enclosures.     

How does reading direction modulate perceptual asymmetry effects?

Left-side bias effects refer to a bias towards the left side of the stimulus/space in perceptual/visuospatial judgments, and are argued to reflect dominance of right hemisphere processing. It remains unclear whether reading direction can also account for the bias effect. Previous studies comparing readers of languages read from left to right with those read from right to left (e.g., French vs. Hebrew) have obtained inconsistent results. As a language that can be read from left to right or from right to left, Chinese provides a unique opportunity for a within-culture examination of reading direction effects. Chinese participants performed a perceptual judgment task (with both face and Chinese character stimuli; Experiment 1) and two visuospatial attention tasks (the greyscales and line bisection tasks; Experiment 2) once before and once after a reading task, in which they read Chinese passages either from left to right or from right to left for about 20 min. After reading from right to left, participants showed significantly reduced left-side bias in Chinese character perceptual judgments but not in the other three tasks. This effect suggests that the role of reading direction on different forms of left-side bias may differ, and its modulation may be stimulus-specific.     

Representation of two geometric features of the environment in the domestic chick (<Emphasis Type="Italic">Gallus gallus</Emphasis>)

We report experiments based on a novel test in domestic chicks (Gallus gallus), designed to examine the encoding of two different geometric features of an enclosed environment: relative lengths of the walls and amplitude of the corners. Chicks were trained to search for a food reward located in one corner of a parallelogram-shaped enclosure. Between trials, chicks were passively disoriented and the enclosure was rotated, making reorientation possible only on the basis of the internal spatial structure of the enclosure. In order to reorient, chicks could rely on two sources of information: the relative lengths of the walls of the enclosure (associated to their left-right sense order) and the angles subtended by walls at corners. Chicks learned the task choosing equally often the reinforced corner and its rotational equivalent. Results of tests carried out in novel enclosures, the shapes of which were chosen ad hoc (1) to induce reorientation based only on the ratio of walls lengths plus sense (rectangular enclosure), or (2) to induce reorientation based only on corner angles (rhombus-shaped enclosure), suggested that chicks encoded both features of the environment. In a third test, in which chicks faced a conflict between these geometric features (mirror parallelogram-shaped enclosure), reorientation seemed to depend on the salience of corner angles. These results shed light on the elements of the environmental geometry which control spatial reorientation, and broaden the knowledge on the geometric representation of space in animals.     

Visualising fragrances through colours: the mediating role of emotions

To facilitate communication about fragrances, one can use the colours people tend to associate with their smells. We investigated to what extent odour-colour correspondences for fine fragrances can be accounted for by underlying emotional associations. Odour-colour matches and degree-of-fit judgments revealed that odours were matched to colours non-randomly. Matching colours differed mainly on blackness (brightness), and less on chromaticness (saturation) and hue. Furthermore, we found a consistent negative relationship between odour-colour degree-of-fit ratings and the difference between the odour scores and the colour scores on one of the emotion dimensions (pleasure). This suggests that emotional associations may partly underlie odour-colour correspondences.     

Decisions about the axes of disoriented shapes

Subjects were timed as they made decisions about the location of an asterisk placed to the left, right, top, or bottom of disoriented shapes, and their reaction times were plotted as a function of the angular departure of the shapes from the upright. In Experiment 1, the shapes were letters, and the functions suggested that the subjects generally mentally rotated some internal representation of each letter to the upright in order to decide whether the asterisk was to the left or the right, regardless of whether the letters were vertically symmetrical (A, T, U, V), horizontally symmetrical (B, C, D, E), or asymmetrical (F, G, R, L). For decisions about top and bottom, mental rotation rarely occurred, although there was some evidence for it in the case of horizontally symmetrical letters. Experiment 2 showed that mental rotation was not involved when subjects made one response if the asterisk was to the left or right, and another if it was at the top or bottom. In Experiment 3, the shapes were relatively unfamiliar architectural symbols, and in this case mental rotation was most strongly induced by those decisions requiring mirror-image discrimination, that is, left-right decisions for vertically symmetrical shapes and top-bottom decisions for horizontally symmetrical ones. Taken overall, the results suggest that there are two task ingredients that may induce mental rotation: One is the labeling of the left and right sides of a disoriented shape, and the other is the discrimination of mirror images.     

Coding location in enclosed spaces: is geometry the principle?

Both animals and human toddlers can find an object in a rectangular enclosure after they have been disoriented. They use geometric cues (relative lengths of walls) to discriminate among different corners (e.g. long wall to the left, short to the right). It has been claimed that this ability is 'modular', i.e. exclusively geometric. The present study demonstrates that the ability toddlers exhibit is a more general one, namely, an ability to discriminate relative quantity. Using a square enclosure, we show that toddlers use the relative sizes of the figures on different walls to characterize different corners. We also show that they do not use simple non-relative features to distinguish different corners. Possible reasons for differences in the ability to use relative versus non-relative cues are discussed.     

Another look at category effects on colour perception and their left hemispheric lateralisation: no evidence from a colour identification task

The present study aimed to replicate category effects on colour perception and their lateralisation to the left cerebral hemisphere (LH). Previous evidence for lateralisation of colour category effects has been obtained with tasks where a differently coloured target was searched within a display and participants reported the lateral location of the target. However, a left/right spatial judgment may yield LH-laterality effects per se. Thus, we employed an identification task that does not require a spatial judgment and used the same colour set that previously revealed LH-lateralised category effects. The identification task was better performed with between-category colours than with within-category task both in terms of accuracy and latency, but such category effects were bilateral or RH-lateralised, and no evidence was found for LH-laterality effects. The accuracy scores, moreover, indicated that the category effects derived from low sensitivities for within-blue colours and did not reflect the effects of categorical structures on colour perception. Furthermore, the classic “category effects” were observed in participants’ response biases, instead of sensitivities. The present results argue against both the LH-lateralised category effects on colour perception and the existence of colour category effects per se.     

Morphological patterns and their colour

This study analyzed qualitative aspects in perception, particularly the relationship between morphological aspects of biological shapes and colour. The experiment reported by the study assessed the functional relation between shape and colour and, in particular, the relations among the patterns of shapes appearing in perceptual configurations, as well as certain characteristics of colour. Participants were shown 32 natural images and were asked to match them with a colour. The results indicated that some figures were more frequently associated (positively or negatively) with some colours instead of others. Type of shape, texture, and three-dimensionality were important elements in the participants' choices. Rounded figures and non-holed figures had positive matches with red; elongated figures were associated with colours between blue and green; and holed figures showed positive matches with colours between green and yellow. Type of shape and texture also exhibited a relationship with the warmth of the colour.     

Effects of surround/test field luminance ratio on induced colour

Abstract.— According to Kirschmann's third law the induced colour is at its maximum when the inducing and induced fields are of equal luminance. Later studies (Kinney, 1962) show the induced colour to be most pronounced at a luminance ratio (inducing/induced) of about 4/1. In the present study the amount of colour induced into an achromatic test field was determined for one inducing colour, red, by letting observers judge the colour strength of the induced field. The test (or induced) field luminance was varied to give luminance ratios between 0.5/1 and 2/1. The results show that both colour strength and blackness increase as the luminance ratio is increased. The fact that the test field was judged even to have maximum chromatic colour strength and maximum blackness at the same time is discussed in relation to the method used and in relation to earlier studies on the "mode of appearance" of colours and the bidimensionality of achromatic colours.     

Split-brain reveals separate but equal self-recognition in the two cerebral hemispheres

To assess the ability of the disconnected cerebral hemispheres to recognize images of the self, a split-brain patient (an individual who underwent complete cerebral commissurotomy to relieve intractable epilepsy) was tested using morphed self-face images presented to one visual hemifield (projecting to one hemisphere) at a time while making "self/other" judgments. The performance of the right and left hemispheres of this patient as assessed by a signal detection method was not significantly different, though a measure of bias did reveal hemispheric differences. The right and left hemispheres of this patient independently and equally possessed the ability to self-recognize, but only the right hemisphere could successfully recognize familiar others. This supports a modular concept of self-recognition and other-recognition, separately present in each cerebral hemisphere.     

Acting intentionally and the side-effect effect

The concept of acting intentionally is an important nexus where theory of mind and moral judgment meet. Preschool children's judgments of intentional action show a valence-driven asymmetry. Children say that a foreseen but disavowed side effect is brought about "on purpose" when the side effect itself is morally bad, but not when it is morally good. This is the first demonstration in preschoolers that moral judgment influences judgments of whether something was done on purpose (as opposed to judgments of purpose influencing moral judgment). Judgments of intentionality are usually assumed to be purely factual. That these judgments are sometimes partly normative-even in preschoolers-challenges current understanding. Young children's judgments regarding foreseen side effects depend on whether the children process the idea that the character does not care about the side effect. As soon as preschoolers effectively process the theory-of-mind concept "not care that P," children show the side-effect effect.     

Colour Discrimination And Monitoring Theories of Consciousness

According to the monitoring theory of consciousness, a mental state is conscious in virtue of being represented in the right way by a monitoring state. David Rosenthal, William Lycan, and Uriah Kriegel have developed three different influential versions of this theory. In order to explain colour experiences, each of these authors combines his version of the monitoring theory of consciousness with a specific account of colour representation. Even though Rosenthal, Lycan, and Kriegel disagree on the specifics, they all hold that colours are represented by a single type of mental state. The main goal of this paper is to show that a more complex account of colour representation is needed for the monitoring theory of consciousness to do justice to the phenomenology of colour experiences. In particular, I will argue that the fine-grained character of colour experience—that is, the fact that perceivers can become conscious of small differences between colours—requires that colour representation be construed in terms of two different types of mental states, namely sensory states that represent appearance properties and colour representations that represent physical colours.     

Navigation as a source of geometric knowledge: young children's use of length, angle, distance, and direction in a reorientation task

Geometry is one of the highest achievements of our species, but its foundations are obscure. Consistent with longstanding suggestions that geometrical knowledge is rooted in processes guiding navigation, the present study examines potential sources of geometrical knowledge in the navigation processes by which young children establish their sense of orientation. Past research reveals that children reorient both by the shape of the surface layout and the shapes of distinctive landmarks, but it fails to clarify what shape properties children use. The present study explores 2-year-old children's sensitivity to angle, length, distance and direction by testing disoriented children's search in a variety of fragmented rhombic and rectangular environments. Children reoriented themselves in accord with surface distances and directions, but they failed to use surface lengths or corner angles either for directional reorientation or as local landmarks. Thus, navigating children navigate by some but not all of the abstract properties captured by formal Euclidean geometry. While navigation systems may contribute to children's developing geometric understanding, they likely are not the sole source of abstract geometric intuitions.     

Incidental Recall of Colour Information by Children and Adults

The ability to recall colours that have only been experienced incidentally (i.e. without deliberately being learnt) is an important aspect of eyewitness recall. However, little is known about the accuracy of adults or children's incidental recall of colours, and the results from previous studies of incidental colour memory have been contradictory—some have found that participants have very good recall for colours, other studies have found very poor recall for colours. Previous studies have not compared adults' and children's performance in the same experiment. This experiment tested 4-year-olds, 6-year-olds, 9-year-olds and adults who were shown a model room, containing six pieces of furniture. While participants were watching, a different miniature item was placed on each of the pieces of furniture in the model room. There were six items and each had a different colour. After a delay of 30 minutes participants were given a surprise memory test to assess their recall for the colour and location of the items. All the age groups were very accurate at recalling both the items' colours and their locations. The implications of accurate incidental colour recall for eyewitness performance are discussed.     

Right up there: hemispatial and hand asymmetries of altitudinal pseudoneglect

Background

Pseudoneglect is a normal left sided spatial bias observed with attempted bisections of horizontal lines and a normal upward bias observed with attempted bisections of vertical lines. Horizontal pseudoneglect has been attributed to right hemispheric dominance for the allocation of attention. The goal of this study was to test the hypothesis that the upward bias in vertical line bisection may also relate to right hemispheric dominance for the allocation of attention and/or action-intention.

Methods

Twenty right handed healthy adults were asked to bisect vertical lines presented in the midsagittal plane (center space) and in sagittal planes to the left and right of the midsagittal plane (left and right hemispace) when using a pen held in either the right or left hand.

Results

Vertical line bisections were biased upward in all three sagittal planes and higher in left than right hemispace. However, bisections made with the left hand were lower than those made with the right hand.

Discussion

Whereas these results suggest a left hemispace-right hemispheric visuospatial attentional upward bias and a relative left hemispheric-right hand upward action-intentional bias, further studies are needed to document this intentional versus attentional bias and to understand the brain mechanisms that produce these biases.     

Perceptual biases in processing facial identity and emotion

Normal observers demonstrate a bias to process the left sides of faces during perceptual judgments about identity or emotion. This effect suggests a right cerebral hemisphere processing bias. To test the role of the right hemisphere and the involvement of configural processing underlying this effect, young and older control observers and patients with right hemisphere damage completed two chimeric faces tasks (emotion judgment and face identity matching) with both upright and inverted faces. For control observers, the emotion judgment task elicited a strong left-sided perceptual bias that was reduced in young controls and eliminated in older controls by face inversion. Right hemisphere damage reversed the bias, suggesting the right hemisphere was dominant for this task, but that the left hemisphere could be flexibly recruited when right hemisphere mechanisms are not available or dominant. In contrast, face identity judgments were associated most clearly with a vertical bias favouring the uppermost stimuli that was eliminated by face inversion and right hemisphere lesions. The results suggest these tasks involve different neurocognitive mechanisms. The role of the right hemisphere and ventral cortical stream involvement with configural processes in face processing is discussed.     

Where Danger Lies: The Spatial Priming of Negative Affect

Conditioning research has found that organisms associate negative affect with the location of a previous negative experience. This investigation sought to determine whether spatial factors would also influence priming effects pertaining to evaluative judgments. The authors hypothesized that negative affective primes should bias subsequent evaluations to a greater degree when targets are presented at the same location. Accordingly, participants rated a series of negative and neutral words appearing in either a left or right location on a computer screen. Across 3 studies, targets were evaluated more negatively when they occurred in the same location as a negative prime. Overall, the results are novel in linking spatial and social cognitive factors in the priming of negative affect.     

Revelation and Transparency in Colour Vision Refuted: A Case Oo Mind/Brain Identity and Another Bridge over the Explanatory Gap

Russell (1912) and others have argued that the real nature of colour is transparentto us in colour vision. It's nature is fully revealed to us and no further knowledgeis theoretically possible. This is the doctrine of revelation. Two-dimensionalFourier analyses of coloured checkerboards have shown that apparently simple,monadic, colours can be based on quite different physical mechanisms. Experimentswith the McCollough effect on different types of checkerboards have shown thatidentical colours can have energy at the quite different orientations of Fourierharmonic components but no energy at the edges of the checkerboards, thusrefuting revelation. It is concluded that this effect is not explained by a superveniencedispositional account of colour as proposed by McGinn (1996). It was argued that theMcCollough effect in checkerboards was an example of a local mind/body reduction(Kim 1993), by which the different characteristics of identical colours falsifies revelation. This reduction being based on both physical and neurological mechanisms led to a clear explanation of the perceive phenomenal effects and thus laid a small bridge over the explanatory gap.     

The ideologically objectionable premise model: Predicting biased political judgments on the left and right

This paper introduces the ideologically objectionable premise model (IOPM), which predicts that biased political judgments will emerge on both the political left and right, but only when the premise of a judgment is not ideologically objectionable to the perceiver. The IOPM generates three hypothesized patterns of bias: biases among both those on the left and right, bias only among those on the right, and bias only among those on the left. These hypotheses were tested within the context of the dual process motivational model of ideological attitudes (DPM; Duckitt, 2001), which posits that right-wing authoritarianism (RWA) and social dominance orientation (SDO) are related but distinct ideological attitudes. Across two studies, all three IOPM hypotheses were tested and supported on the RWA ideological attitude dimension, and two of the three IOPM hypotheses were tested and supported on the SDO dimension. These findings indicate that the context of the judgment is an important determinant of whether biases emerge in political judgment.