Dyslexia linked to talent: global visual-spatial ability

Dyslexia has long been defined by deficit. Nevertheless, the view that visual-spatial talents accompany dyslexia has grown, due to reports of individuals with dyslexia who possess visual-spatial strengths, findings of elevated incidence of dyslexia in certain visual-spatial professions, and the hypothesis that left-hemisphere deficits accompany right-hemisphere strengths. Studies have reported superior, inferior, and average levels of visual-spatial abilities associated with dyslexia. In two investigations, we found an association between dyslexia and speed of recognition of impossible figures, a global visual-spatial task. This finding suggests that dyslexia is associated with a particular type of visual-spatial talent-enhanced ability to process visual-spatial information globally (holistically) rather than locally (part by part).     

Age-related differences in learning disabled and skilled readers' working memory

This study determines whether age-related deficits in learning disabled (LD) readers' working memory performance reflect delays in retrieval efficiency and/or storage capacity. The study compared LD and skilled readers' working memory performance (N=226) across four age groups (7, 10, 13, and 20) for phonological, visual-spatial, and semantic information under initial (non-cued), gain (cues that bring performance to an asymptotic level), and maintenance conditions (asymptotic conditions without cues). The important results were that LD readers' working memory performance was inferior to skilled readers on verbal and visual-spatial working memory tasks across all age groups and these differences increased on gain and maintenance conditions when compared to initial conditions. These reading group differences remained when age, reading, and mathematics were partialed from the analysis. The results support a general capacity explanation of reading group differences that is not totally dependent on reading skill. These differences in capacity reflect demands placed on both the accessing of new information and the maintenance of old information that extend beyond the phonological system.     

When can children handle referential opacity? Evidence for systematic variation in 5- and 6-year-old children's reasoning about beliefs and belief reports

Five- and 6-year-olds (N=51) heard stories in which a character sorted items into two locations. Either the character had a false belief about one of the items (e.g., thought a tin contained biscuits, not Lego), or was only partially informed of an item's dual identity (e.g., did not know that a tie was a present). Children found it easier to reject a report of the character's belief that described the true state of affairs when the character had a false belief (e.g., Is Fred's uncle thinking "where shall I put this Lego?"), than to reject one in which an object known to the character was described using a term of which she was ignorant (e.g., Is Mum thinking "where shall I put this present?"). Similarly, children found it easier to predict the character's incorrect sorting of the target items for false belief (with food not toys) than for dual identity (in the wardrobe not with things to take on a visit). Correct reasoning about beliefs and reports of beliefs that misrepresent an object does not imply mastery of the fact that beliefs represent an object in a particular way.     

The relationship between theory of mind and episodic memory: evidence for the development of autonoetic consciousness

The study investigated a link between theory of mind and episodic memory involving autonoetic consciousness (). Eighty-nine Japanese 4- to 6-year-olds received two versions of a false belief task, a task of aspectuality or knowledge origins, and four memory tests. After controlling for age, most theory of mind abilities showed no interrelations, and own and other's belief understandings in deceptive appearance tasks were solely related to source memory, but not to free recall, temporal ordering, or working memory. Moreover, even when age and verbal intelligence were controlled, the association between representational change and source memory was highly significant in 6-year-olds but not in 4- and 5-year-olds. Results suggest that during development only a particular kind of theory of mind ability is integrated with episodic memory.     

Infants' learning,memory, and generalization of learning for bimodal events

Study 1 investigated whether infants 3 and 7 months of age show differential learning of and memory for sight-sound pairs depending on whether or not temporal synchrony was present; memory was assessed after a 10-min and 1-week interval. Study 2 examined whether 7-month-olds show generalization of learning when they encounter novel bimodal events that are similar (changes in size, orientation, or color, and spectral sound properties) to the sight-sound pairs learned 1 week earlier based on temporal synchrony. For Study 1, infants received a familiarization phase followed by a paired-comparison preference procedure to assess for learning of the sight-sound pairs. One week later a memory test was given. Results confirmed that 7-month-olds had no difficulty learning auditory-visual pairings regardless of whether or not events were temporally synchronous, and they remembered these 10 min and 1 week later. In contrast, 3-month-olds showed poorer learning of sight-sound associations in the no-synchrony than synchrony conditions, and memory for sight-sound pairs 1 week later was shown only for the synchrony conditions. Results for Study 2 revealed generalization of learning of bimodal pairings under all stimulus conditions after a 1-week interval at 7 months of age. Implications of these findings for development of intersensory knowledge are discussed.     

Machiavellianism and Theory of Mind in people affected by schizophrenia

CONTEXT: People affected by schizophrenia show deficits in social interaction (Cramer, Bowen, & O'Neill, 1992); such a deficit may stem from an alteration in the representation of mental states. OBJECT: In this study we have examined 42 people affected by schizophrenia, diagnosed according to DSM-IV criteria, by testing them with an instrument (the Mach IV scale, Christie & Geis, 1970) assessing "Machiavellian Intelligence" according to Niccolò Machiavelli's assertions. Schizophrenic subjects were compared to a sample of normal controls, matched for age, sex, and education. OBJECTIVE: The aim of our study was to evaluate if there were correlations between the ability to understand other people's mental states and the capacity for interpreting "Machiavellian expressions." RESULTS: Results show that people affected by schizophrenia are less able to use Machiavellian-style "tactical" abilities than controls. CONCLUSION: Such a disability seems to be correlated to poor mentalising abilities.     

Acetylcholine modulation of neural systems involved in learning and memory

Extensive evidence supports the view that cholinergic mechanisms modulate learning and memory formation. This paper reviews evidence for cholinergic regulation of multiple memory systems, noting that manipulations of cholinergic functions in many neural systems can enhance or impair memory for tasks generally associated with those neural systems. While parallel memory systems can be identified by combining lesions with carefully crafted tasks, most—if not all—tasks require the combinatorial participation of multiple neural systems. This paper offers the hypothesis that the magnitude of acetylcholine (ACh) release in different neural systems may regulate the relative contributions of these systems to learning. Recent studies of ACh release, obtained with in vivo microdialysis samples during training, together with direct injections of cholinergic drugs into different neural systems, provide evidence that release of ACh is important in engaging these systems during learning, and that the extent to which the systems are engaged is associated with individual differences in learning and memory.     

The effects of aging on location-based and distance-based processes in memory for time

Retrieving when an event occurred may depend on an estimation of the age of the event (distance-based processes) or on strategic reconstruction processes based on contextual information associated with the event (location-based processes). Young and older participants performed a list discrimination task that has been designed to dissociate the contribution of both types of processes. An adapted Remember/Know/Guess procedure [Can. J. Exp. Psychol. 50 (1996) 114] was developed to evaluate the processes used by the participants to recognize the stimuli and retrieve their list of occurrence. The results showed that aging disrupts location-based processes more than distance-based processes. In addition, a limitation of speed of processing and working-memory capacities was the main predictor of age-related differences on location-based processes, whereas working-memory capacities mediated partly age differences on distance-based processes.     

Is there a causal link from phonological awareness to success in learning to read?

In this review, we re-assess the evidence that phonological awareness represents a skill specific to spoken language that precedes and directly influences the process of reading acquisition. Longitudinal and experimental training studies are examined in detail, as these are considered most appropriate for exploring a causal hypothesis of this nature. A particular focus of our analysis is the degree to which studies to date have controlled for existing literacy skills in their participants and the influence that these skills might have on performance on phonological awareness tasks. We conclude that no study has provided unequivocal evidence that there is a causal link from competence in phonological awareness to success in reading and spelling acquisition. However, we believe that such a study is possible and outline some ideas for its design and implementation.     

Five-year-old children's difficulty with false belief when the sought entity is a person

A total of 153 children (excluding those who erred on control questions), mainly 5 and 7 years of age, participated in two experiments that involved tests of false belief. In the task, the sought entity was first at Location 1 and then, unknown to the searching protagonist, it moved to Location 2. In Experiment 1, performance was well below ceiling in 5-year-olds when the sought entity was a person, and this contrasted with a task in which the sought entity was a physical object. Performance was especially inaccurate when the sought person moved of his or her own volition rather than when the sought person was requested to move by a third party. Interestingly, 5-year-olds were more likely to nominate Location 1 when asked where the searching protagonist would look first than when asked what he or she would do next. In Experiment 2, however, 5-year-olds also tended to nominate Location 1 following a question that included the word "first" even in a test of true belief--a patently incorrect response. Altogether, the results suggest that 5-year-old children have considerable difficulty with a test of false belief when the sought entity is a person acting under his or her own volition. This suggests that 5-year-olds' handle on states of belief is surprisingly fragile in this kind of task.