Why do parallel cortical systems exist for the perception of static form and moving form?

This article analyzes computational properties that clarify why the parallel cortical systems V1----V2, V1----MT, and V1----V2----MT exist for the perceptual processing of static visual forms and moving visual forms. The article describes a symmetry principle, called FM symmetry, that is predicted to govern the development of these parallel cortical systems by computing all possible ways of symmetrically gating sustained cells with transient cells and organizing these sustained-transient cells into opponent pairs of on-cells and off-cells whose output signals are insensitive to direction of contrast. This symmetric organization explains how the static form system (static BCS) generates emergent boundary segmentations whose outputs are insensitive to direction of contrast and insensitive to direction of motion, whereas the motion form system (motion BCS) generates emergent boundary segmentations whose outputs are insensitive to direction of contrast but sensitive to direction of motion. FM symmetry clarifies why the geometries of static and motion form perception differ--for example, why the opposite orientation of vertical is horizontal (90 degrees), but the opposite direction of up is down (180 degrees). Opposite orientations and directions are embedded in gated dipole opponent processes that are capable of antagonistic rebound. Negative afterimages, such as the MacKay and waterfall illusions, are hereby explained as are aftereffects of long-range apparent motion. These antagonistic rebounds help to control a dynamic balance between complementary perceptual states of resonance and reset. Resonance cooperatively links features into emergent boundary segmentations via positive feedback in a CC loop, and reset terminates a resonance when the image changes, thereby preventing massive smearing of percepts. These complementary preattentive states of resonance and reset are related to analogous states that govern attentive feature integration, learning, and memory search in adaptive resonance theory. The mechanism used in the V1----MT system to generate a wave of apparent motion between discrete flashes may also be used in other cortical systems to generate spatial shifts of attention. The theory suggests how the V1----V2----MT cortical stream helps to compute moving form in depth and how long-range apparent motion of illusory contours occurs. These results collectively argue against vision theories that espouse independent processing modules. Instead, specialized subsystems interact to overcome computational uncertainties and complementary deficiencies, to cooperatively bind features into context-sensitive resonances, and to realize symmetry principles that are predicted to govern the development of the visual cortex.     

What form of memory underlies novelty preferences?

Novelty preferences (longer fixations on new stimuli than on previously presented stimuli) are widely used to assess memory in nonverbal populations, such as human infants and experimental animals, yet important questions remain about the nature of the processes that underlie them. We used a classical conditioning paradigm to test whether novelty preferences reflect (1) a stimulus-driven bias toward novelty in visual selective attention or (2) explicit memory for old stimuli. Results indicated that conditioning affected adults’ looking behavior in the visual paired comparison, but not their recognition memory judgments. Furthermore, the typically observed novelty preference occurred only when a bias toward novelty had no competition from a bias toward salience due to conditioning. These results suggest that novelty preferences may reflect attentional processes and implicit memory to a greater degree than explicit memory, a finding with important implications for understanding memory in nonverbal populations and the development of memory in humans.     

Bentham’s binary form of maximizing utilitarianism

Jeremy Bentham is often interpreted as defending a satisficing, rather than maximizing, version of utilitarianism, where an act is right as long as it produces more pleasure than pain. This lack of maximization is surprising given Bentham’s maximizing slogan ‘the greatest happiness of the greatest number’. Against the satisficing interpretation, I argue that Bentham consistently defends a maximizing version of utilitarianism, where an act’s consequences are compared to those of not performing the act. I show that following this version of utilitarianism requires that one realizes the greatest happiness for all affected individuals.     

Are psychology's tribes ready to form a nation?

Collaboration between social psychologists and cognitive neuroscientists is giving rise to a new approach that its practitioners call 'social cognitive neuroscience'. Scientists from each discipline are using the theories and techniques of the other to generate new answers to fundamental questions about attitudes, beliefs, the self, moral judgment, and other issues. Is this interdisciplinary endeavor an exercise in wishful thinking and good intentions, or is it a preview of psychology's future?     

Note on the generalized form of Weber’s Law

Institute for Perception, Soesterberg, Netherlands In this note it is argued that Δ I = k (I + I_n)P as an expression for the generalized Law of Weber (Treisman, 1964) is confusing. The expression ΔI = kIP + i_n should be preferred in the light of the evidence available.     

Note on the generalized form of Weber’s Law

In this note it is argued that ΔI=k(I + I_n)P as an expression for the generalized Law of Weber (Treisman, 1964) is confusing, The expression ΔI=kIP + i_n should be preferred in the light of the evidence available.     

Movement contributes to infants’ recognition of the human form

Three experiments demonstrate that biological movement facilitates young infants’ recognition of the whole human form. A body discrimination task was used in which 6-, 9-, and 12-month-old infants were habituated to typical human bodies and then shown scrambled human bodies at the test. Recovery of interest to the scrambled bodies was observed in 9- and 12-month-old infants in Experiment 1, but only when the body images were animated to move in a biologically possible way. In Experiment 2, nonbiological movement was incorporated into the typical and scrambled body images, but this did not facilitate body recognition in 9- and 12-month-olds. A preferential looking paradigm was used in Experiment 3 to determine if infants had a spontaneous preference for the scrambled versus typical body stimuli when these were both animated. The results showed that 12-month-olds preferred the scrambled body stimuli, 9-month-olds preferred the typical body stimuli and the 6-month-olds showed no preference for either type of body stimuli. These findings suggest that human body recognition involves integrating form and movement, possibly in the superior temporal sulcus, from as early as 9 months of life.     

How do children form impressions of persons? They average

The experiment reported was concerned with impression formation in children. Twelve subjects in each of Grades K, 2, 4, and 6 rated several sets of single trait words and trait pairs. The response scale consisted of a graded series of seven schematic faces which ranged from a deep frown to a happy smile. A basic question was whether children use an orderly integration rule in forming impressions of trait pairs. The answer was clear. At all grade levels a simple averaging model adequately accounted for pair ratings. A second question concerned how children resolve semantic inconsistencies. Responses to two highly inconsistent trait pairs suggested that subjects responded in the same fashion, essentially averaging the two traits in a pair. Overall, the data strongly supported an averaging model, and indicated that impression formation of children is similar to previous results obtained from adults.     

An “outside-in” processing strategy in the perception of form

The discriminability of line segments in a number of different geometric forms was examined. The procedure used was to have one of the lines within a given form drawn thinner than the other lines. The location of the thin line varied randomly within the form, and subjects were required to detect its location. Three observations were made. First, outer line elements were discriminated more accurately than inner line elements. Second, the outer line advantage appeared to reflect an attentional strategy: By presenting inner and outer lines independently, and informing subjects in advance as to whether target lines would be in the inner or outer area of the form, the outer line advantage could be eliminated. Third, consonant with a global attentional strategy, and in opposition to any retinally tied, peripheral-to-central scanning process, an outer-line advantage was evident regardless of whether the fixation point was positioned within or outside the forms, or whether outer lines were more peripheral than inner lines.     

Has the cataphasic form of schizophrenia increased in modern times?

According to our investigations the incidence of cataphasia, which is a subtype of schizophrenia, has become more common in the last years and on average, has started earlier in life. As the central disorder of this illness concerns thinking perhaps there exists a relation of our finding to the rapid modern development of techniques, insofar as the cognitive function is overstrained in childhood and adolescence, when the nervous system has not matured yet. Introverted individuals seem to be at a particular risk. However, it must not be disregarded that cataphasia is an inherited illness which cannot be caused by external influences, but can only be promoted in its manifestation.     

Infants’ identification of three-dimensional form from transformations of linear perspective

The ability of infants to perceive three-dimensional structure from transformations of linear perspective was investigated in two studies. Infants were habituated to the pattern of linear perspective transformations corresponding to a particular three-dimensional object, and their relative preference for that object as compared with a different three-dimensional object was assessed both before and after habituation. The habituation displays showed the distorting shadow cast by a rotating object and therefore provided only transformations of linear perspective as information specifying three-dimensional form. The pre- and posttest displays involved the actual three-dimensional objects and provided binocular, shading, and texture information specifying three-dimensional form, but did not provide informative transformations of linear perspective. In Study 1, 6-month-olds showed changes in preference from pre- to posttest that were related to the identity of the object whose shadow they had seen during habituation; 4-month-olds, however, did not show preference changes related to the habituation object. In Study 2, rhythm information that may have served as a basis for responding in Study 1 was eliminated from the test displays. Six-month-olds again showed changes in preference that were dependent on their habituation experience. It is concluded that, by 6 months of age, infants are able to perceive object structure from the isolated cue of transformations of linear perspective. The findings are discussed with reference to infants’ three-dimensional form perception based on other cues and also with reference to the emergence of certain spatially related moter activities.     

Career adapt-abilities scale — Icelandic form: Psychometric properties and construct validity

This study examined the psychometric characteristics and construct validity of the Icelandic form of the Career Adapt-Abilities Scale (CAAS-Iceland). The CAAS consists of four scales that measure concern, control, curiosity, and confidence as psychosocial resources for managing occupational transitions, developmental tasks, and work traumas. The 24-item measure was translated from English and administered to 1566 Icelandic students aged 14–30. Internal consistency estimates of reliability for the subscale and total scores ranged from .77 to .92. The construct validity of the measure was tested using confirmatory methods. The results indicated that the four-factor hierarchical model of career adaptability shows an acceptable fit in Iceland. The mean scores on the scales are high compared to the other countries, indicating that there may be problems with the translation of the response scale. The results indicate that the CAAS-Icelandic Form is reliable and valid and can be used with minor modifications in career counseling and research in Iceland.     

Can residual lexical knowledge concern word form rather than word meaning?

We described a patient with a dramatic deficit of both word comprehension and naming but with good preservation of visual pictorial semantics. On word-picture matching, his performances were slightly better than expected based on the observed lexical semantic disorder; in addition, the patient, who maintained good preservation of his underlying phonology, showed a tendency to point to the picture phonologically related to the target. In order to interpret these data, we advanced the hypothesis that the patient, in spite of his virtually complete inability to name, would be able, in a word-picture matching task, to "covertly" (i.e., preverbally) retrieve the name from the picture and to use this name to attempt a match with the phonological form of the stimulus word. This mechanism, that we called "phonological" comprehension, would allow the identification of the correct target and would explain the choice of the phonologically related foil that was sometimes selected.     

What is the “front” of a simple geometric form?

A total of 670 undergraduate Ss were tested in three studies conducted in an attempt to define a set of cues that minimally specify perceived “frontness” and “backness” of objects. In Experiment I, Ss were instructed to identify the “front” and “back” of printed squares to which no, one, or two circles were attached. In Experiment II, different Ss made the same kind of judgment to a wider range of geometric forms. In Experiment III, different Ss judged the direction of “imagined” movement of forms from Experiment I. The results indicated that the “front” and “back” are asymmetric opposite sides, with “front” the side most different from the rest and the side toward which the form is imagined to be moving.     

On the general form of Stevens’ law for loudness and softness

The loudness of a 1000-Hz tone at weak sound pressures and its softness at intense ones were scaled by the method of magnitude estimation. Estimates of loudness plotted as a function of sound pressure on double logarithmic coordinates showed the well-documented steepening near threshold. A similar steepening occurred in the softness function at high intensities. Stevens’ law, which is linear on these coordinates, could be recovered either by translating the pressure scale to a new origin, or by translating the response scale. Translations of the response scale were preferred because they produced functions in which loudness and softness were reciprocally related, whereas transformations of the stimulus made the softness function almost three times as steep as the loudness function.     

Subvocalization in auditory-verbal imagery: just a form of motor imagery?

Previous studies have provided evidence for subvocal rehearsal (inner voice) and phonological storage (inner ear) in auditory-verbal imagery. The question remains to be answered whether the inner voice mainly involves higher-order language systems, or primarily relies on motor systems associated with articulatory-kinesthetic processing. On the basis of models of auditory imagery and working memory, we predicted that, if auditory-verbal imagery is a form of motor imagery, performance on a novel auditory-verbal imagery task would be affected by concurrent articulatory suppression as well as by concurrent finger tapping. In contrast, we predicted that performance on a visuospatial control task would be significantly affected by concurrent tapping only. The auditory imagery task consisted of indicating, for bisyllabic words, the syllable that carried the stress. A significant interaction was observed between task (verbal vs. visual) and type of interference (articulatory suppression vs. tapping). Tapping affected reaction times on the visual task significantly more than articulatory suppression. However, both interference conditions affected the verbal task to an equal extent. The present findings confirm the role of subvocalization in auditory-verbal imagery and provide evidence for a strong involvement of articulatory-kinesthetic motor processing.