Right hemisphere dysfunction in nonverbal learning disabilities: Social, academic, and adaptive functioning in adults and children.

Addresses recent research on social and nonverbal learning disabilities. Involvement of right hemispheric dysfunction in these disabilities has been hypothesized, as studies with adults have suggested that documented right hemisphere damage may lead to deficits in social skills, prosody, spatial orientation, problem solving, and recognition of nonverbal cues. Studies of children purported to evidence nonverbal learning disabilities are reviewed and compared with the results from studies of adults with right hemisphere damage. Specific subtypes of nonverbal learning disabilities are reviewed, including the nonverbal perceptual-organization-output subtype, Asperger's syndrome, Developmental Gerstmann syndrome, left hemisyndrome, right hemisphere syndrome, and right parietal lobe syndrome. Finally, implications and future research needs are addressed. The need for a diagnostic nosology and improved and validated intervention techniques is stressed as is early identification of these types of specific nonverbal learning disabilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Functional organization of the right nondominant cortex: Evidence from electrical stimulation.

Studied discrete functional localization for visuo-perceptual, spatial, and nonverbal memory tasks in conjunction with focal electrical stimulation of the exposed right-dominant cortex during awake craniotomies in 22 patients. Results provide evidence for discrete functional localization in the right, nondominant hemisphere. Performance on each task was significantly impaired in association with stimulation of some, but not all, sites in comparison with performance on nonstimulation control trials. There was, generally, a strong dissociation of sites involved in separate functions across individual Ss. Contrary to the notion of diffuse functional organization in the nondominant hemisphere, visuospatial functions in the right hemisphere appear to be as discretely localized as verbal functions in the left hemisphere. Language and language-related functions of naming, reading, short-term verbal memory, nonverbal oral-facial movement, and phonemic identification were assessed in a subgroup of 10 Ss in conjunction with right nondominant cortical stimulation. In right-handed Ss, no disruptions of these tasks were seen with stimulation of sites outside the right face motor cortex itself. In 2 case studies, there was evidence for right cortical involvement in the mediation of 2 nonphonetic symbol-based language systems: Japanese Kanji and Fortran. (French abstract) (72 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Frontotemporal dementia selectively impairs transitive reasoning about familiar spatial environments.

Although patients with frontotemporal dementia (FTD) are known to exhibit a wide range of cognitive and personality difficulties, some evidence suggests that there may be a degree of selectivity in their reasoning impairments. Based on a recent review of the neuroimaging literature on reasoning, the authors hypothesized that the presence or absence of familiar content may have a selective impact on the reasoning abilities of patients with FTD. Specifically, the authors predicted that patients with frontal-variant FTD would be more impaired when reasoning about transitive arguments involving familiar spatial environments than when reasoning about identical logical arguments involving unfamiliar spatial environments. As predicted, patients with FTD were less accurate than normal controls only when the content of arguments involved familiar spatial environments. These results indicate a degree of selectivity in the cognitive deficits of this patient population and suggest that the frontal-temporal lobe system may play a necessary role in reasoning about familiar material. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for two types of spatial representations: Hemispheric specialization for categorical and coordinate relations.

Analyses of human object recognition abilities led to the hypothesis that 2 kinds of spatial relation representations are used in human vision. Evidence for the distinction between abstract categorical spatial relation representations and specific coordinate spatial relation representations was provided in 4 experiments. These results indicate that Ss make categorical judgments—on/off, left/right, and above/below—faster when stimuli are initially presented to the left cerebral hemisphere, whereas they make evaluations of distance—in relation to 2 mm, 3 mm, or 1 in. (2.54 cm)—faster when stimuli are initially presented to the right cerebral hemisphere. In addition, there was evidence that categorical representations developed with practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The impact of print exposure quality and inference construction on syllogistic reasoning.

This study extended the work of S. Siddiqui, R. F. West, and K. E. Stanovich (1998), who studied the link between general print exposure and syllogistic reasoning. It was hypothesized that exposure to certain text structures that contain well-delineated logical forms, such as popularized scientific texts, would be a better predictor of deductive reasoning skill than general print exposure, which is not sensitive to the quality of an individual's reading activity. Furthermore, it was predicted that the ability to generate explanatory bridging inferences while reading would also be predictive of syllogistic reasoning. Undergraduate students (N = 112) were tested for vocabulary, nonverbal cognitive ability, exposure to general print, exposure to popularized scientific literature, and the ability to comprehend texts distinguished by the number of inferences that must be generated to support comprehension. Hierarchical multiple regression analyses showed that a combined measure of exposure to general and scientific literature was a significant predictor of syllogistic reasoning ability. Additionally, the ability to comprehend high-inference-load texts was related to solving syllogisms that were inconsistent with world knowledge, indicating an overlap in deductive reasoning skill and text comprehension processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex differences in right hemisphere tasks

We tested the hypothesis that sex differences in spatial ability and emotional perception are due to sex differences in intrahemispheric organization of the right hemisphere. If the right hemisphere is differently organized by sex-primarily specialized for spatial ability in men, but primarily specialized for emotional perception in women-then there should be a negative correlation between spatial ability and emotional perception within sex, and the greatest disparity between abilities should be found in people with characteristic arousal of the right hemisphere. Undergraduate men (N = 86) and women (N = 132) completed tests of Mental Rotation, Surface Development, Profile of Nonverbal Sensitivity, Progressive Matrices, and Chimeric Faces. Although the expected pattern of sex differences was observed, there was no evidence for the hypothesized negative correlation between spatial ability and emotional perception, even after statistical control of general intelligence.     

Training the elderly on the ability factors of spatial orientation and inductive reasoning.

Examined the effects of cognitive training with 132 female and 97 male Ss (aged 64–95 yrs) who were classified as having remained stable or having declined over the previous 14-yr interval on each of 2 primary abilities, spatial orientation and inductive reasoning. Ss who had declined on one of these abilities received training on that ability; Ss who had declined on both abilities or who had remained stable on both were randomly assigned to the spatial orientation or inductive reasoning training programs. Training outcomes were examined within an ability-measurement framework with empirically determined factorial structure. Significant training effects, at the level of the latent ability constructs, occurred for both spatial orientation and inductive reasoning. These effects were general in that no significant interactions with decline status or gender were found. It is concluded that training interventions were effective both in remediating cognitive decline on the target abilities and in improving the performance of stable Ss. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hand preference of the common marmoset (Callithrix jacchus): Problem solving and responses in a novel setting.

Common marmosets (Callithrix jacchus) with a right-hand preference displayed shorter latencies to enter a novel room containing novel structures and objects, touched more objects, and performed more touches and more parallax movements than marmosets with a left-hand preference. These results are consistent with specialization of the right hemisphere (left hand) for fear and negative emotional states and specialization of the left hemisphere (right hand) for approach and positive emotional states. There were no effects of age or sex on any of these behaviors. This relationship between exploration and hand preference did not occur when the marmosets were tested in the home cage with a novel problem, although significant effects of both age and dominance were found in solving the problem. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender, alcoholism, and neuropsychological functioning.

35 female and 25 male alcoholics (mean age 45) performed significantly more slowly than similar numbers of age-matched nonalcoholic controls on the Tactual Performance Test (TPT), especially with the left hand. Alcoholism effects were not significant for TPT Memory or Location. Women recalled significantly more shapes but correctly located fewer of those remembered than did men. Results suggest that (a) alcoholism effects on tactual–spatial performance are similar in men and women, (b) right hemisphere functions or less well-practiced skills may be selectively vulnerable to alcoholism, and (c) sex differences exist in tactual memory and spatial location abilities. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contributions of computational fluency to cross-national differences in arithmetical reasoning abilities.

To test the hypothesis that American students have an advantage over East Asian students in arithmetical reasoning once computational abilities and IQ are controlled, 237 U.S. and 218 Chinese college students took arithmetical computational and reasoning tests, along with IQ and spatial abilities tests. Significant national differences favoring the Chinese students were found for all but the spatial test. After controlling for IQ and computational fluency, the Chinese advantage on the arithmetical reasoning tests was still significant but substantively smaller in magnitude. A similar pattern was observed for a sample of 55 U.S. and 80 Chinese high school students. The results, though not fully consistent with the hypothesis, are consistent with the position that the East Asian advantage in computational abilities contributes to the advantage in arithmetical reasoning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Facilitating children's proportional reasoning: A model of reasoning processes and effects of intervention on strategy change.

In this study, 140 fourth graders were asked to solve proportion problems about juice-mixing situations both before and after an intervention that used a manipulative model or other materials in 3 experiments. Using a manipulative model based on children's prior knowledge about crowdedness and equal distribution was effective in letting children discover a unit strategy, which was useful for solving proportion problems. The model was more effective for those who had an appropriate representation but could not correctly compare juice concentrations than it was for those who didn't have the representation. On the basis of this study, different approaches appear to be necessary to facilitate children's proportional reasoning, depending on the reasoning process (representation or comparison) with which children are having difficulty. Interventions on the basis of the process model and learning that builds on intuitive knowledge are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recent research on human problem solving.

Though the research on human problem solving behavior from 1946 to 1957 has been characterized by a variety of problem tasks, diverse taxonomy of behavioral processes, non-dimensionalized variables, and a relative lack of integration of data and theory, several tentative conclusions are apparent. Among these it is suggested that problem solving performance varies as a function of simple sets and a few kinds of complex sets, of level of problem difficulty, of aids toward solution, and of such S variables as sex, age, and reasoning ability. 114-item bibliog. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deep dyslexia and the right hemisphere hypothesis: Evidence from the U.S.A. and the U.S.S.R.

Discusses the theory that asserts that the residual reading abilities seen in deep dyslexia entirely reflect the operation of an intact right hemisphere reading system rather than a partially disabled left hemisphere reading system. Evidence from an experiment with normal Ss in a report by the present author and colleagues (1983) is presented, which suggests that the right hemisphere contains no lexical entries for abbreviations that can be accessed by visual presentation. Data are presented from studies by K. E. Patterson (1980; see also PA, Vols 63:12203 and 64:10691) on 2 male deep dyslexic's understanding of printed abbreviations, along with observations of a young female deep dyslexic who was tested on understanding of abbreviations and on letter-naming abilities. Considerable sparing of the ability to obtain semantic information from printed abbreviations was evidenced in all 3 Ss. This contrast suggests that the current right hemisphere account of the residual reading abilities seen in deep dyslexia is not a sufficient one and should be modified. (French abstract) (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exploring the Mozart effect among high school students.

Much past work on the Mozart effect--the temporary increase in performance on spatial relations tasks following listening to Mozart--tried determining if the cause is due to neurological priming or changes in general arousal. Results have been mixed, and no work to date has attempted to examine this phenomenon in high school students. The present study sought to address these gaps in the extant literature by examining the neurological and arousal hypotheses in this previously unstudied population of adolescents. Toward this end, 86 high school students were randomly assigned to Mozart or control (silence) conditions, then assessed on arousal levels and spatial reasoning. Results indicated that those in the Mozart condition had higher spatial reasoning scores, but were not systematically more or less aroused. Decreased arousal, regardless of listening conditioning, was related to lower spatial reasoning. While arousal and listening condition were not related to each other, inclusion of both in a single model negated these direct effects. Implications for future work on these phenomena are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The interpretation of sentence ambiguity in patients with unilateral focal brain surgery

Interpretations of ambiguous sentences were studied in patients with unilateral anterior temporal lobectomy or selective amygdalo-hippocampectomy. The sentences represented lexical and syntactic ambiguities. In both left- and right-sided groups, regardless of type of surgery, total mean score on the test was below normal. Left-sided cases, regardless of type of surgery, provided significantly fewer alternative interpretations than right-sided cases. The results suggest greater left than right hemisphere specialization in both lexical and syntactic processing, but also suggest right hemisphere involvement in resolution of lexical ambiguity.     

Asymmetric effects of ovarian hormones on hemispheric activity: Evidence from dichotic and tachistoscopic tests.

Previous studies have suggested a role of endogenously cycling ovarian hormones in the modulation of perceptual asymmetries. In the present investigation, participants were given perceptual asymmetry tests including verbal and nonverbal tachistoscopic and dichotic listening tasks during the menstrual and midluteal phases of the menstrual cycle. Salivary levels of estrogen and progesterone were also measured. Analyses of performance on the tachistoscopic tests revealed that left visual field, but not right visual field, accuracy was significantly lower for both verbal and nonverbal tasks at the midluteal phase than at the menstrual phase. Right ear performance on the nonverbal dichotic test was significantly reduced at the midluteal phase. Results suggest suppression of right hemisphere processing areas and possible reduction in callosal transfer efficiency at higher levels of ovarian steroids. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lateral eye movements and hemispheric asymmetry: A critical review.

Eye movements to the left or right have been hypothesized to reflect activation of the cerebral hemisphere contralateral to the direction of gaze. This hypothesis was tested by comparing the direction of lateral eye movements (LEMs) following questions designed to engage the left or right hemisphere. The evidence from such studies was equivocal. Fewer than half found the predicted pattern of more right LEMs for left-hemisphere questions, and conceptual and methodological ambiguities in the questions, scoring, and experimental situation made interpretation of these studies difficult. In addition, findings showing more upward eye movements and more stares for right-hemisphere questions cannot be incorporated into the hemispheric asymmetry model of LEMs. Studies on individual differences in LEM patterns indicated a fair degree of stability and some consistency in their correlates. However, since "right" and "left movers" do not differ in verbal or spatial abilities, there is little justification for linking LEM patterns with "hemisphericity." It is concluded that further research on the relationship between directional ocular events and cognitive-affective processes is required before inferences about hemispheric function can be drawn from studies of lateral eye movements. (2? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Merds that laugh don't like mushrooms": Evidence for deductive reasoning by preschoolers.

Examined the relationship between the development of logical processes required in deductive reasoning and their occasions of use. 24 verbal syllogism problems were presented to 40 children (aged 4.2–5.1 yrs). The problems were systematically varied in content (fantasy premises, premises incongruent with real-world events, premises congruent with real-world events), form, and order of presentation of problem types. Results indicate that Ss were capable of making deductive inferences required in solving syllogism problems and that these abilities were displayed in constrained conditions. The relationship of the problem content to real-world knowledge and the sequence of presentation of the problem types affected the display of logical abilities. (46 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Chimpanzee (Pan troglodytes) relational matching: Playing by their own (analogical) rules.

Chimpanzees (Pan troglodytes) have been known to exhibit rudimentary abilities in analogical reasoning (Flemming, Beran, Thompson, Kleider, & Washburn, 2008; Gillian, Premack, & Woodruff, 1981; Haun & Call, 2009; Thompson & Oden, 2000; Thompson, Oden, & Boysen, 1997). With a wide array of individual differences, little can be concluded about the species' capacity for analogies, much less their strategies employed for solving such problems. In this study, we examined analogical strategies in 3 chimpanzees using a 3-dimensional search task (e.g., Kennedy & Fragaszy, 2008). Food items were hidden under 1 of 2 or 3 plastic cups of varying sizes. Subsequently, chimpanzees searched for food under the cup of the same relative size in their own set of cups—reasoning by analogy. Two chimpanzees initially appeared to fail the first relational phase of the task. Meta-analyses revealed, however, that they were instead using a secondary strategy not rewarded by the contingencies of the task—choosing on the basis of the same relative position in the sample. Although this was not the intended strategy of the task, it was nonetheless analogical. In subsequent phases of the task, chimpanzees eventually learned to shift their analogical reasoning strategy to match the reward contingencies of the task and successfully choose on the basis of relative size. This evidence not only provides support for the analogical ape hypothesis (Thompson & Oden, 2000), but also exemplifies how foundational conceptually mediated analogical behavior may be for the chimpanzee. (PsycINFO Database Record (c) 2011 APA, all rights reserved)