The role of stimulus axis salience in children's ability to mentally rotate unfamiliar figures

A mental rotation task with unfamiliar stimuli was presented to 5-year-old (n = 36) and 8-year-old children (n = 36). The stimuli contained either an intrinsic salient axis (S +) or no salient axis (s-). Results showed that both 5-year-old and 8-year-old children were able to perform the mental rotation task with the S + stimulus. However, 5-year-old children had difficulties in performing the mental rotation task with the S- stimulus. These results suggest that there are limitations in mental rotation abilities of young children. The ability to encode and mentally rotate unfamiliar stimuli containing no salient axis seems to improve between the ages of 5 and 8.     

Measuring the size of mental images

Mental images seem to have a size; the experimental problem was to map that image size onto a scale of physical measurement. To this end, two experiments were conducted to measure the size of mental images in degrees of visual angle. In Experiment 1, college students employed light pointers to indicate the horizontal extent of projected mental images of words (the letter string, not the referent). Imagined words covered about 1.0 degress of visual angle per letter. In Experiment 2, a more objective eye-movement response was used to measure the visual angle size of imagined letter strings. Visual angle of eye movement was found to increase regularly as the letter distance between the fixation point and a probed letter position increased. Each letter occupied about 2.5 degrees of visual angle for the four-letter strings in the control/default size condition. Possible relations between eye movements and images are discussed.     

Rushton’s contributions to the study of mental ability

This essay describes Rushton’s contribution to examining the nexus of intelligence, race, and genetics, specifically what I termed “Spearman’s hypothesis”. It states that Black–White differences are “most marked in just those [tests] which are known to be saturated with g”. I (Jensen) had confirmed this hypothesis using large data sets in the 1970s and 1980s and also found that Black–White differences were most marked on the more heritable rather than the more cultural subtests. Rushton confirmed and extended these findings in many highly innovative ways and demonstrated Spearman’s hypothesis applied among samples of Gypsy Roma in Serbia, and East Asian, European, South Asian, Colored and Black samples in South Africa. He has not only documented group differences in brain size, intelligence, life span, family structure, infant mortality, developmental precocity, personality, and temperament, and rates of two egg twinning, and crime among East Asians, Europeans, and Africans, but also provided a life history theory that explains them.     

Ability to generate mental images in students of art

To evaluate the ability to generate mental images and its relations to artistic training, 44 undergraduates were presented with a list of selected fragments from 40 characters in the Roman alphabet. Subjects provided those letters suggested by the fragments for as many items as possible within a 90-second interval. It was hypothesized that students who had received college training in studio art would be able to produce a greater number of candidate images than students not trained in art, resulting in more correct answers and higher scores. Results confirmed the hypothesis. Trained subjects completed significantly more of the letters on the image-generation task than did those not trained in art (p=.0001). This suggests that superior ability to generate images is associated with artistic training. Further, these results imply that, to the degree to which artistic training reflects ability, image generation may also be related to artistic ability.     

A field is to play. Enacting mental images of the soundscape

The article mainly focuses on the presentation of “A field is to play”, a collaborative and interactive installation dedicated to the recording and the reenacting of the relationship between the inhabitants of Mazama, WA – a small community in the USA – and their sonic environment. Through multimedia local interactions, enaction and emplacement, the project aimed to give expression to the many, individual and socially constructed, mental images of the local soundscape. A physical, interactive audio installation presented excerpts from individual interviews, emplacing and activating such mental representations, to merge them back into the environment. The artistic intervention was conceived as a localised process, acting through an engagement with publics. The soundscape itself, and its mental representations, were manipulated both as relational media, and subject matter. The presentation is preceded by three sections that introduce the theoretical context at the origin of the installation starting from urban theory in architecture, to the role of public art up to the discussion around the topic of soundscape, in a path from the most general issues to those more related to the specific character of the installation. The conclusion pulls together the theoretical and the applied sections and offers some response to the questions raised in the introduction. Through a theoretical engagement with the installation, it asks the reader to rethink the relationship between sound, memory and mental images.     

The relationship of specific mental ability measures compared to a general mental ability measure to quality and quantity performance on a clerical job sample

Barrett (1993) presented evidence that mental ability measures designed specifically for the prediction of performance in tasks and jobs have validity at least equal to that of tests of general mental ability, while having advantages such as lower adverse impact. The current study demonstrates that the match in specificity of predictor and criterion can be attained through simple changes in the scoring of standard mental and clerical ability tests. A sample of 51 university students completed a battery of pre-employment tests and, a week or two later, worked on a clerical job sample. The results indicated that quality of performance (number of errors on the task) was best predicted using the number of errors made on the predictor tests while quantity of work was only predicted by the number correct. A test of general mental ability did not correlate with either criterion. These results contradicted the conclusions of Schmidt (1993) that specific ability tests have no incremental validity above a general ability test.Ralph Alexander died before this report was complete. Consequently, the conclusions are those of the first two authors.     

The emergence of the ability to track a character's mental perspective in narrative

In comprehending stories, adults create mental models from which they follow the actions of the characters from the characters' different mental vantage points. Using a novel methodology, this study is the first to examine when children attain the narrative ability to track the mental perspective of characters. That is, when do children follow the actions of a story to different locations that a character is thinking about? The results of Study 1 demonstrate that this ability is nascent in 3-year-olds but adult-like by age 5. Study 2 demonstrates that 3-year-olds' difficulty is the result of the mention of the character's mental state per se rather than task complexity. Together, these studies shed new light on the development of narrative cognition in humans.     

Comparison processes on visual mental images

Three experiments were conducted to test whether visual mental images and visual perceptual representations possess equivalent structural properties and undergo functionally equivalent comparison processes. In Experiment 1, subjects were required to perform asame-different letter classification in which the two letters were shown in succession. The first letter in the pair either was actually presented (perceptual condition) or had to be actively generated (imaginal condition). Both conditions showed that (1) response latencies fordifferent decisions decreased as a function of the degree of difference (segment effect), and (2) same decisions were faster than the fastestdifferent ones (fast same effect). In Experiment 2, the imaginal condition only was employed, but no imagery instructions were given and very strict time constraints were assigned. In spite of these restrictions, subjects apparently generated and used visual images, as attested by the fact that the results were comparable to those of the previous experiment. In Experiment 3, three experimental manipulations were introduced to prevent the use of visual images. Such manipulations proved effective, as shown by the disappearance of the segment effect. It was concluded that in the visual modality images and percepts are equivalent in structure and are processed in a very similar way.     

Verbal ability and mental processing speed

The notion that verbal ability is related to mental processing speed was examined using tasks that systematically varied in semantic content. Subjects' reaction times were measured in five tasks involving arrow matching, physical identity word matching, or taxonomic identity word matching. The findings indicated that matching tasks using different decision rules and different stimuli were all related to verbal ability. In fact, reaction time for subjects required to judge whether two arrows pointed in the same direction was the best predictor of verbal ability. One explanation of the results is that speed of information processing (a general factor) may be the important component of verbal ability which is measured by seemingly different matching tasks.     

Verbal ability and mental processing speed

The notion that verbal ability is related to mental processing speed was examined using tasks that systematically varied in semantic content. Subjects’ reaction times were measured in five tasks involving arrow matching, physical identity word matching, or taxonomic identity word matching. The findings indicated that matching tasks using different decision rules and different stimuli were all related to verbal ability. In fact, reaction time for subjects required to judge whether two arrows pointed in the same direction was the best predictor of verbal ability. One explanation of the results is that speed of information processing (a general factor) may be the important component of verbal ability which is measured by seemingly different matching tasks.     

Attending to a misoriented word causes the eyeball to rotate in the head

Torsional eye movements are triggered by head tilt and a rotating visual field. We examined whether attention to a misoriented form could also induce torsion. Thirty-six observers viewed an adapting field containing a bright vertical Une, and then they viewed a display that was composed of two misoriented words (one rotated clockwise, the other counterclockwise, by 15°, 30°, or 45°). The subjects were instructed to attend to one of the words. The subjects’ adjustments of a reference line to match the tilt of the afterimage showed that attention to a misoriented word produces torsional eye movement (verified with direct measurements on 4 additional subjects). This eye movement reduces the retinal misorientation of the word by about 1°. The results of this study reinforce the linkage between selective attention and eye movements and may provide a useful tool for dissecting different forms of “mental rotation” and other adjustments in internal reference frames. Apparent-motion displays confirming that the eye rotated in the head may be downloaded from www.psychonomic.org/archive.     

Dissociation between the mental rotation of visual images and motor images in unilateral brain-damaged patients

Deficits in the mental rotation of body parts and of external objects can be doubly dissociated (Rumiati, Tomasino, Vorano, Umiltà, & De Luce, 2001; Sirigu & Duhamel, 2001; Tomasino, Rumiati, & Umità, in press). The aim of this study was to replicate this finding and to then investigate the relevance of the specific hemispheres in these deficits. Nine patients with unilateral lesions (five in the Left Hemisphere and four in the Right) and 20 control subjects, performed a single task requiring mental rotation of hands, and two tasks requiring mental rotation of external objects. RH patients were impaired in the rotation of external objects, but showed intact performance on the rotation of hands; the opposite pattern was found for LH patients. These results support the view that the LH contributes to the mental rotation of hands, recruiting processes specific to motor preparation, while the RH is specialized for mental rotation of external objects.     

Extending neuropsychological assessments into the primary mental ability space

A battery of 17 neuropsychological tests (including the CERAD battery) and 17 psychometric ability tests were administered to a sample of 499 participants of the Seattle Longitudinal study who had been given the psychometric ability tests seven and 14 years earlier. The neuropsychological tests were projected into a 5-factor psychometric ability space by means of extension analysis. The concurrent regressions of the neuropsychology tests on the psychometric ability tests were then used to estimate neuropsychology test scores from the psychometric ability tests administered in 1984, 1991 and 1998. Neuropsychologists then rated the study participants as either normal, suspect or cognitively impaired in 1998. Changes in estimated test scores were computed over seven and fourteen years. Significant odds ratios between normal and cognitively impaired groups were found for all neuropsychological tests over the proximal period and for most tests over the 14-year period. Similar findings occurred for the odds ratios between the normal and suspect groups for the most proximal 7-year changes.     

An assessment of the contributions of general mental ability and personality characteristics to management success

This study investigated the relationship of general mental ability and a select set of personality characteristics to a constructed criterion of management success which reflected relative rate of career progress. Data were collected in the context of an operational individual assessment program from a total of 296 persons in nonmanagement up through top management positions in a variety of service and manufacturing organizations. Primary (n=148) and hold-out (n=148) samples were identified and a stepwise multiple regression analysis was performed on the primary sample. Cross-validation indicated that a two-variable linear composite accounted for 20.9% of the variance in the dependent variable.     

Enhanced mental rotation ability in time-space synesthesia

Time-space synesthesia is a variant of sequence–space synesthesia and involves the involuntary association of months of the year with 2D and 3D spatial forms, such as arcs, circles, and ellipses. Previous studies have revealed conflicting results regarding the association between time-space synesthesia and enhanced spatial processing ability. Here, we tested 15 time-space synesthetes, and 15 non-synesthetic controls matched for age, education, and gender on standard tests of mental rotation ability, spatial working memory, and verbal working memory. Synesthetes performed better than controls on our test of mental rotation, but similarly to controls on tests of spatial and verbal working memory. Results support a dissociation between visuo-spatial imagery and spatial working memory capacity, and suggest time-space synesthesia is associated only with enhanced visuo-spatial imagery. These data are consistent with the time-space connectivity thesis that time-space synesthesia results from enhanced connectivity in the parietal lobe between regions supporting the representation of temporal sequences and those underlying visuo-spatial imagery.     

Sensory features of mental images in the framework of human actions

What determines the sensory impression of a self-generated motor image? Motor imagery is a process in which subjects imagine executing a body movement with a strong kinesthetic and/or visual component from a first-person perspective. Both sensory modalities can be combined flexibly to form a motor image. 90 participants of varying ages had to freely generate motor images from a large set of movements. They were asked to rate their kinesthetic as well as their visual impression, the perceived vividness, and their personal experience with the imagined movement. Data were subjected to correlational analyses, linear regressions, and representation similarity analyses. Results showed that both action characteristics and experience drove the sensory impression of motor images with a strong individual component. We conclude that imagining actions that impose varying demands can be considered as reexperiencing actions by using one’s own sensorimotor representations that represent not only individual experience but also action demands.