Italian developmental dyslexic and proficient readers: where are the differences?

Italian dyslexic children are characterized by a pervasive reading speed deficit, with relatively preserved accuracy. This pattern has been associated with predominant use of the nonlexical reading procedure. However, there is no evidence of a deficit in the lexical route of Italian dyslexics. We investigated both lexical and nonlexical reading procedures in dyslexic children through two marker effects, namely, the word frequency effect and the effect of contextual grapheme-to-phoneme conversion rules. Although dyslexics were slower and less accurate than controls, they were affected by word frequency, grapheme contextuality, and their interaction in a similar manner as average readers. These results show the use of lexical reading in Italian dyslexics, and refute the claim of a deficit in whole-word processing with consequent over-reliance on the nonlexical route.     

Preparing for perception and action (I): the role of grouping in the response-cuing paradigm

Human skilled behavior requires preparatory processes that selectively make sensory and motor systems more efficient for perceiving the upcoming stimulus and performing the correct action. We review the literature concerning these preparatory processes as studied by response-cuing paradigm, and propose a model that accounts for the major findings. According to the Grouping Model, advance or precue information directs a dynamic process of subgroup making-that is, a process of stimulus- and response-set reconfiguration-whereby the internal representation of the task is simplified. The Grouping Model assigns a critical role to the unit of selection, with Gestalt factors and interresponse dependencies mediating the formation and strength of stimulus and response subgroups. In a series of five experiments, we manipulated perceptual and motoric grouping factors, and studied their independent and interactive effects on the pattern of precuing benefits. Generally, the results were consistent with the Grouping Model's account of response-cuing effects.     

Saccade-stepping interactions revise the motor plan for obstacle avoidance

The authors used a stimulus-response compatibility paradigm to assess the effect of changing the estimated time to obstacle contact. A limb-selection cue was presented in different phases of gait to young (n = 5) and to older (n = 4) adults while they were moving toward a foam obstacle in the walking path. A downward saccade was initiated after the cue; the saccade typically occurred during the stance phase of the target limb (the foot cued to lead the step over the obstacle). The mean saccade-step latency after the cue was on the order of -500 ms in both young and elderly participants. On reaching the obstacle, both groups generated an upward saccade approximately -300 ms before target footlift in both groups. Saccades following the limb-selection cue appeared to direct the gaze toward footfall targets just beyond the obstacle, whereas saccades generated just before obstacle footlift moved the gaze to the forward-looking direction. The elderly had significantly longer saccade-trailing-footlift latencies and prolonged gaze-fixation times than did the younger adults. Transient disruptions in optical flow appeared to be necessary for successful obstacle-avoidance behavior when there was an unexpected change in the estimated time to obstacle contact.     

Updating and inhibition processes in working memory: a comparison between Alzheimer's type dementia and frontal lobe focal damage

A large debate has recently focused on the componential nature of the working-memory system (), as evidenced by functional-imaging studies and by using more sophisticated experimental paradigms. The present work aims at further disentangling the role and effects of central executive (CE) and of phonological loop (PL). It is suggested that maintaining active verbal information mostly relates to an intact PL, while the inhibition of interfering information preponderantly involves the CE. To distinguish these effects, two groups of brain damaged patients were administered with an updating task. Frontal lobe patients showed major difficulties in inhibiting interfering information, an ability requiring an involvement of the CE component. In contrast, Alzheimer's dementia patients evidenced a relative impairment in maintaining relevant information, requiring the intervention of the PL.     

Age-related Differences in the Production of Textual Descriptions

Narratives produced by 69 healthy Italian adults were analyzed for age-related changes of microlinguistic, macrolinguistic and informative aspects. The participants were divided into five age groups (20-24, 25-39, 40-59, 60-74, 75-84). One single-picture stimulus and two cartoon sequences were used to elicit three stories per subject. Age-related differences were found with respect to semantic paraphasias, paragrammatisms, syntactic complexity, degree of both local and global coherence, local coherence errors (like ambiguous referencing), and in the level of informativeness conveyed by the stories. The results showed some null effects of age, some effects with a sharp drop in performance in the oldest group, and several effects suggesting a gradual decrease in performance across age groups. No age differences were found with respect to phonological selection and noun-verb ratio. In the proportion of details vs. main themes, the results indicated a possibly better story construction ability in the middle aged (40-59) and young elderly (60-74) groups compared to the younger or the oldest group. Story-type (single picture vs. picture sequence) had a significant influence on some macrolinguistic and informativeness measures.     

Word length effect in early reading and in developmental dyslexia

Vocal reaction times were measured in Italian dyslexics and in proficient readers while they read single words. Three groups of control participants (for a total of 79) were tested. All were in the first, second or third grade of elementary school. Nine third graders with a low level of reading ability when assessed by standard reading procedures were also tested. Results indicated that vocal RTs of control participants were faster and less sensitive to word length as a function of age; also, there was a particularly marked change between first and second graders. Dyslexics' vocal RTs and errors were much worse than those of peer control participants and resembled those of first grade controls. It is suggested that normal readers in an orthographically transparent language (Italian) adopt a lexical strategy quite early in their learning. On the contrary, dyslexics seem unable to learn this mode of processing and continue to use a sub-lexical reading procedure.     

Inhibition of return to an occluded object depends on expectation

Inhibition of return (IOR) is indexed by slower reaction times to targets presented at previously attended locations or objects. If a moving object is occluded, some studies find IOR, others do not. Four experiments examined whether this inconsistency hinges on the observer's expectation as to whether the object continues to exist at the end of its motion sequence. Results showed that observer expectation is a powerful determining factor: IOR occurs only if the observer expects the object to continue to exist. In contrast, if the object is not occluded, IOR occurs only if the object remains on view immediately before the target is presented. It was concluded that 2 factors, object continuity and observer expectation, mediate both location- and object-based IOR.     

Holism, Strawberries and Hairdryers

The paper "Does Epistemological Holism lead to Meaning – Holism" (Cozzo, 2002) touches one of the main problems of a molecularist theory of meaning: how to restrict the class of inferences connected with a word, in order to define the sense of the word. I will discuss the starting point of this approach, mainly the pre-theoretical criterion against meaning holism: meaning holism, following a well-known argument by Dummett, reduces communication to a mystery. However there is a strong background assumption of this argument: communication is sharing the same meanings. Accepting this assumption without acknowledging it makes the entire proposal more problematic than it appears at first sight. In what follows I will try to clarify the possibility of a different reaction to meaning holism, putting forward some distinctions which come to light when the above stated assumption is made explicit. Then, some other comments will follow on the difficulty of avoiding extreme meaning holism, even within Cozzo's elegant attempt to implement a molecularist vision; in the end, his notion of the sense of a word will appear to be difficult to define, if these holistic aspects of language take the space they deserve even in his theory. I conclude with two remarks regarding two relevant requirements for a theory of meaning (conservativeness and harmony). This revised version was published online in June 2006 with corrections to the Cover Date.     

Dominance of global visual properties at birth

Six experiments are reported that were aimed at demonstrating the presence in newborns of a perceptual dominance of global over local visual information in hierarchical patterns, similar to that observed in adults (D. Navon, 1977, 1981). The first four experiments showed that, even though both levels of visual information were detectable by the newborn (Experiments 1A and 1B), global cues enjoyed some advantage over local cues (Experiments 2 and 3). Experiments 4A and 4B demonstrated that the global bias was strictly dependent on the low spatial frequency content of the stimuli and vanished after selective removal of low spatial frequencies. The results are interpreted as suggesting parallels between newborns' visual processing and processing later in development.     

Reliability of DSM-IV anxiety and mood disorders: implications for the classification of emotional disorders

The reliability of current and lifetime Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) anxiety and mood disorders was examined in 362 outpatients who underwent 2 independent administrations of the Anxiety Disorders Interview Schedule for DSM-IV: Lifetime version (ADIS-IV-L). Good to excellent reliability was obtained for the majority of DSM-IV categories. For many disorders, a common source of unreliability was disagreements on whether constituent symptoms were sufficient in number, severity, or duration to meet. DSM-IV diagnostic criteria. These analyses also highlighted potential boundary problems for some disorders (e.g., generalized anxiety disorder and major depressive disorder). Analyses of ADIS-IV-L clinical ratings (0-8 scales) indicated favorable interrater agreement for the dimensional features of DSM-IV anxiety and mood disorders. The findings are discussed in regard to their implications for the classification of emotional disorders.