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In reality decision tasks, subjects have to decide whether a picture represents a real or an unreal object: the perceptual representation of the stimulus is compared with the representations of objects that have been seen previously and are stored in the so called Structural Description System (SDS); when matching occurs, the corresponding conceptual knowledge is activated. One critical issue in cognitive neuropsychology is the relationship between the SDS and semantic memory. Several clinical cases show double-dissociations, but evidence suggesting an interaction between the two systems has also been gathered. In the present study we aimed at investigating whether semantic and perceptual variables play a role at the level of the structural description system. We created a set of 260 black-and-white line drawings of objects, half real and half unreal. In the unreal group we manipulated the visual and semantic characteristics of the stimuli so as to obtain five categories of false objects: Kroll & Potter-like pictures; scrambled pictures; pictures with metrical alterations; non semantically-related chimeras and semantically-related chimeras. Twenty normal subjects performed the reality decision task. Reaction times and accuracy were recorded. Longer reaction times and poorer accuracy were found for the semantically-related chimeras, with respect to all the other categories. Our findings suggest that semantic knowledge supports visual object recognition and thus that the semantic memory store and the structural description system are highly interactive. Next step will be to verify the involvement of the semantic system in real-unreal judgments in patients with semantic memory impairment.

Lexical‐semantic variables such as word frequency, imageability and age of acquisition have long been studied in order to shed light on the cognitive processes underlying the performance of normal and aphasic speakers [1, 2]. However, little is known about the role of these variables in Chinese. Twenty Chinese aphasic patients (either fluent or non‐fluent) and twenty healthy individuals matched for age and education participated in this study. They were asked to read aloud written words and to name pictures of objects and actions. The probability of success on each item was estimated through mixed logit models (MLM) [3] on the basis of word frequency, imageability, age of acquisition, grammatical class (nouns vs. verbs), and morphological structure (simple vs. complex words). The use of MLM allowed us to assess the effects of the predictors: (i) more precisely, because of the reduction of the error variance; (ii) both in the whole sample of participants and in the individual subjects. The set of significant predictors differs in reading aloud and picture naming, with imageability playing an important role in the former task, and age of acquisition in the latter. More importantly, grammatical class, morphological structure, and their interaction turned out to be significant predictors in both task, indicating that simple nouns are much easier than complex nouns, but no difference arose between simple and complex verbs (see Figure). Because grammatical class and morphological structure played a crucial role in explaining the performance of healthy and brain‐damaged individuals, we carried out separate MLM analyses on (a) simple nouns, (b) simple verbs, (c) complex nouns, and (d) complex words in both tasks. In the analyses focusing specifically on complex nouns and complex verbs, we introduced the grammatical class of the compound constituents as an additional predictor. Interestingly, this factor did not play a relevant role in explaining the performance of normal an

Although the functional independence of noun and verb lexical retrieval has been reliably established, it is not clear whether the processing of these grammatical classes recruits separate neural circuits [1]. Contrasting results might have emerged because different studies used different experimental and baseline tasks. The meta‐analysis described in this study aims at identifying (i) brain regions that are consistently associated with a given grammatical class across different tasks, and (ii) brain areas whose grammatical‐class specificity is modulated by the task used. We considered 620 activation peaks reported in 27 neuroimaging studies on nouns and verbs. A hierarchical cluster algorithm was used in order to automatically segregate groups of coordinates into separate clusters. This procedure produced a set of 52 clusters, which were assessed with a binomial test for specificity for grammatical class and/or task, and with a Fisher test for task‐by‐grammatical class interaction. One cluster was associated with nouns across different tasks in the right superior temporal gyrus; verb‐specific clusters were instead observed in the middle temporal gyrus bilaterally, in the right precuneus and in the left lingual gyrus. Other four clusters – located in the left inferior frontal gyrus, in the left insula, and in the left middle occipital gyrus – showed a task‐by‐grammatical class interaction. The impact of these results on the current neuroanatomical theories of noun and verb processing [2] will be discussed. [1] Berlingeri, M. et al. (2008), Cognitive Neuropsychology, 25, 528‐558. [2] Cappa, S. & Perani, D. (2003), Journal of Neurolinguistics, 16, 183‐189.

Background: The study explores the ability of fluent and non-fluent aphasic patients to produce verbs using the appropriate argument structure, i.e., a feature specifying the number and type of participants in the event described by the verb. According to Chomsky's Minimalist Program (1995), the lexical entry of a verb contains information about the number of arguments and the thematic roles assigned, which is then mapped onto the sentence argument structure, while Bock and Levelt's (1994; see also Levelt, Roelofs, & Meyer, 1999) model of lexical production assumes that the information regarding verb argument structure (VAS) is part of the lemma and is accessed before the retrieval of the phonological word form, i.e., the lexeme. Aim: Participants were tested to investigate their ability to map thematic information onto the corresponding syntactic argument structure. Methods & Procedures: Seven aphasic patients (five suffering from non-fluent aphasia with agrammatism and two from fluent aphasia) and ten neurologically unimpaired individuals participated in the study. They were given a picture description task formulated in two conditions: in the first condition they were asked to provide a free description of the image, while in the second condition they had to complete the sentence structure provided by the examiner. Patients showing deficits in verb production were also tested for the use of prepositions within prepositional compounds and in a sentence context. Outcomes & Results: Four agrammatic patients and one fluent aphasic patient scored a high rate of argument structure errors in the selection of the appropriate verb, which was employed with an incorrect argument structure. Furthermore, these patients tended to substitute rather than to omit prepositions when required to fill the gap in a sentence. Conclusions: Our results indicate an impaired access to (VAS) and/or in mapping the thematic role information onto the syntactic argument structure. T

Introduction: Although spelling difficulties are constantly associated with developmental dyslexia, they have been largely neglected by the majority of studies in this area. This study analyzes spelling impairments in developmental dyslexia across school grades in Italian, a language with high grapheme-to-phoneme correspondence. Methods: The performances of 33 Italian dyslexic children attending Grades 3 and 5 were compared with those of age-matched control participants. Writing abilities were investigated through a spelling test that included regular words with one-sound-to-one-letter correspondence, regular words requiring the application of context-sensitive conversion rules, words with unpredictable transcription and nonwords with one-sound-to-one-letter correspondence. Results: Both accuracy and error analyses indicate that the spelling impairment assumes different characteristics at different grades: Grade 3 children showed an undifferentiated spelling deficit (involving regular words, regular nonwords and words with unpredictable spelling), whereas the fifth graders were prevalently impaired in writing words with unpredictable transcription. The error analysis confirms these results, with third graders producing a high rate of all types of errors (i.e., phonologically plausible, simple and context-sensitive conversion errors), whereas most errors committed by fifth graders were phonologically plausible. Conclusions: Results are coherent with the hypothesis that dyslexic children learning a shallow orthography suffer from delayed acquisition and some fragility of the sub-word level routine, together with a severe and long-lasting deficit of orthographic lexical acquisition.

LANGUAGE ASSESSMENT IN ACUTE APHASIA Acute aphasia asks for a specific assessment due to the need of a bedside examination and of a discrimination of language impairments from the attention and concentration disorders that usually complement an acute brain damage. We describe here a new bedside aphasia examination for the evaluation of acquired language impairments in Italian. The task (Esame del linguaggio al letto del malato: ELLM) is intended for the acute phase of aphasia, usually during the first week post onset. The test is composed of a series of tasks aimed at measuring the linguistic production (spontaneous speech, automatic series, picture naming, description of a complex image, repetition, reading aloud and spelling) and oral comprehension of an acute brain damaged patient. The examination takes about 20 minutes. Norms for the test use were derived from a sample of 50 healthy participants and 56 patients suffering from different types of language impairment and from different severity. The description of a clinical case clarifies the diagnostic procedure with the ELLM

There is a significant body of psycholinguistic evidence that supports the hypothesis of an access to constituent representation during the mental processing of compound words. However it is not clear whether the internal hierarchy of the constituents (i.e., headedness) plays a role in their mental lexical processing and it is not possible to disentangle the effect of headedness from that of constituent position in languages that admit only head-final compounds, like English or Dutch. The present study addresses this issue in two constituent priming experiments (SOA 250ms) with a lexical decision task. Italian endocentric (head-initial and head-final) and exocentric nominal compounds were employed as stimuli and the position of the primed constituent was manipulated. A first-level priming effect was found, confirming the automatic access to constituent representation. Moreover, in head-final compounds data reveal a larger priming effect for the head than for the modifying constituent. These results suggest that different kinds of compounds have a different representation at mental level: while head-final compounds are represented with an internal head-modifier hierarchy, head-initial and exocentric compounds have a lexicalised, internally flat representation.

In questo studio viene descritta una prova per la valutazione dei deficit di linguaggio acquisiti (afasia) da somministrare in fase acuta, solitamente al letto del malato. Il test ha una durata di somministrazione e correzione di 20-30 minuti. I dati normativi qui riportati sono tratti da un campione di 50 partecipanti sani e 56 pazienti afasici con diversa gravità e tipo di afasia.

In this study we investigated twelve cases of "mixed dysgraphia", a spelling impairment where regular words are spelt better than either ambiguous words or regular nonwords. Two explanations of mixed dysgraphia were formerly offered by Luzzatti et al. (1998): (i) a double functional lesion of the Orthographic Output Lexicon (or damage to its access) and of the Acoustic-to-Phonological Conversion; (ii) some kind of interaction/summation between lexical and sublexical spelling routes when processing regular words. We first analysed whether a double functional lesion was sufficient to explain the mixed dysgraphia, checking acoustic-to-phonological conversion by means of the Repetition of words and nonwords: the answer was positive in 5 cases and uncertain in 3. We tested the remaining 4 cases to see if there was an interaction between lexical and sublexical processing of regular words, quantifying for each patient, on a probabilistic basis, the separate contribution of the residual lexical and sublexical resources. We investigated whether the processing along these routes was simultaneous but independent ("independent cooperation") or if instead there was “interaction”, i.e. the simultaneous activity led to an added increase of efficiency over and above the mere combination of separate success probabilities. For one case the processing along the two routes was independent, in the other 3 cases an interaction resulted. Following the same approach, we found that for the 5 cases with a double functional lesion, the observed success on regular word spelling was higher than that expected on a probabilistic basis, but the interpretation of this finding was different

The progressive increase of prevalence and incidence of dementia require growing attention in identifying subjects with early cognitive impairment. We have evaluated the results of mini mental state examination (MMSE) and CDT in elderly patients affected by MCI and mild dementia and in subjects without cognitive impairment, to measure whether combined use of two well-known cognitive screening tests (MMSE, CDT) is useful to identify precociously subjects with possible MCI. Using the statistical model of binomial logistic regression we have pointed out that CDT better differentiates healthy controls from MCI patients. MMSE, on the contrary of CDT, differentiates MCI patients from subjects affected by dementia. Finally, during screening, administration of both CDT and MMSE can be useful to identify precociously subjects with possible MCI.

The functional independence of noun and verb lexical retrieval has been repeatedly demonstrated over the last decade (e.g., Rapp and Caramazza, 2002); however, the evidence produced so far on whether these processes recruit separate neural circuits is far less clear (e.g., Bedny & Thompson‐Schill, 2006; Berlingeri et al., 2008). This may be due to the lack of homogeneity in the tasks used in the various experiments. The meta‐analysis described in this study aims at disentangling the brain regions that are systematically associated with a given grammatical class from those whose grammatical‐class specificity is modulated by the task used. We collected 620 activation coordinates associated with either nouns or verbs in simple effect analyses from 22 neuroimaging studies published from 1996 to 2008. A hierarchical cluster algorithm was employed adopting the Ward (1963) criterion to automatically segregate groups of coordinates into separate clusters (mean standard deviation < 7.5 mm in the x, y, and z directions for each cluster; Jobard et al., 2003). This procedure produced a set of 49 clusters, which were assessed with a binomial test for specificity for grammatical class and/or task, and with a Fisher test for task‐by‐grammatical class interaction. Two clusters turned out to be associated with nouns across different tasks, while five were associated with verbs (Figure 1a); the locations of these clusters do not support spatially segregated neural circuits for nouns and verbs, as suggested in some previous work (e.g., Cappa & Perani, 2003). Five clusters showed instead a task‐by‐grammatical class interaction (Figure 1b), which was mainly driven by noun‐specific activation in derivational tasks and by verb‐specific activation in picture naming and fluency tasks. These results will be discussed in the light of the cognitive processes entailed by the individual experimental tasks.

Although positive effects of rhythm cueing on motor control in neurological disorders are known, no studies focused on patients suffering from impaired programming of complex actions. One patient suffering from ideomotor apraxia (a potentially ideal experimental paradigm to test the effect of rhythm on high-level motor control) underwent two rehabilitation training sets differing only for the presence/absence of rhythmic cueing. Both trainings increased the patient’s proficiency, but rhythmic cueing was significantly more effective, during the training as well as during the post-training uncued test. IA represent an effective model to test the effects of rhythm on high-level motor control.

The study uses an orthographic judgment task to evaluate the efficiency of the lexical reading route in Italian dyslexic children. It has been suggested that Italian dyslexic children rely prevalently on the sub-word-level routine for reading. However, it is not easy to test the lexical reading route in Italian directly because of the lack of critical items (irregular words), so visual lexical decision tasks and the comprehension/detection of pseudo-homophones are often used. While the former may also be solved on the basis of visual familiarity or phonological re-codification, the latter also involves conceptual and syntactic skills. Eleven dyslexic children participated in the study, performing an orthographic judgment task on stimuli with two phonologically plausible spellings, of which only one was orthographically correct. Their performance was compared with those of 11 proficient readers. The dyslexic children showed selective impairment in detecting phonologically plausible errors, but their performance was normal when required to judge errors inserted in words with regular orthography, i.e., devoid of orthographic ambiguity, and for which a sub-word-level reading procedure is sufficient to guarantee a good performance. Overall, data are coherent with a diagnosis of surface dyslexia, with most children showing defective orthographic lexical processing

The wide variety of techniques and tasks used to study the neural correlates of noun and verb processing has resulted in a body of inconsistent evidence. We performed a functional magnetic resonance imaging (fMRI) experiment to detect grammatical class effects that generalize across tasks. A total of 12 participants undertook a grammatical-class switching task (GCST), in which they were presented with a noun (or a verb) and were asked to retrieve the corresponding verb (or noun), and a classical picture naming task (PNT) widely used in the previous aphasiological and imaging literature. The GCST was explicitly designed to ensure control over confounding variables, such as stimulus complexity or imageability. Conjunction analyses of the haemodynamic responses measured in the two tasks indicated a shared verb-related activation of a dorsal premotor and posterior parietal network, pointing to a strong relationship between verb representation and action-oriented (visuo-)spatial knowledge. On the other hand, no brain area was consistently associated with nouns in both tasks. Moreover, there were task-dependent differences between noun and verb retrieval both at behavioural and at physiological level; the grammatical class that elicited the longest reaction times in both tasks (i.e., verbs in the PNT and nouns in the GCST) triggered a greater activation of the left inferior frontal gyrus. Therefore, we suggest that this area reflects a general increase in task demand rather than verb processing per se.

To date the evidence which has emerged from both anatomo‐correlative and neuroimaging studies investigating the brain areas responsible for noun and verb processing [e.g. 1, 2, 3] is inconsistent; this may be due to the lack of homogeneity in the tasks used in the various experiments. The metanalysis described in this study aims at disentangling brain regions that are systematically associated with a given grammatical class from those whose grammatical‐class specificity is modulated by the task used. We collected 441 activation peak coordinates associated with either nouns or verbs in simple effect analyses from 27 neuroimaging studies published from 1996 to 2008, and employed a hierarchical cluster algorithm adopting the Ward criterion [4] to automatically segregate groups of activation coordinates into separate clusters with mean standard deviations of less than 7.5 mm [5] in the three directions (x, y, z). This procedure produced a set of 37 clusters, which were tested with a chi‐square analysis for specificity for grammatical class and/or task. Nine of these clusters showed a significant task-by-grammatical class interaction, which in derivational tasks was usually caused by noun‐specific activation and in picture naming and fluency tasks by verb‐specific activation. These results are discussed in the light of the cognitive processes underlying the individual experimental tasks. REFERENCES [1] Perani, D., Cappa, S.F., Schnur, T., Tettamanti, M., Collina, S., Rosa, M.M., Fazio, F. (1999). The neural correlates of verb and noun processing. A PET study. Brain, 122, 2337­‐2344. [2] Aggujaro, S., Crepaldi, D., Pistarini, C., Taricco, M., Luzzatti, C. (2006). Neuro-anatomical correlates of impaired retrieval of verbs and nouns: Interaction of grammatical class, imageability and actionality. Journal of Neurolinguistics, 19, 175-194. [3] Tyler, L.K., Russell, R., Fadili, J., Moss, H.E. (2001). The neural representation of nouns and verbs: PET studies. Brain, 124, 1619-1

The mental processing of nominal compounds is still underspecified for several aspects. For instance, there is contrasting evidence about the effect of semantic transparency. Moreover, most studies on compounds were performed in languages that admit only head-final constructions, thus making impossible to disentangle the effect of headedness from that of constituent position. Italian Noun-Noun compounds, conversely, are either head-initial or head-final: exploiting this property of Italian morphology, this study aims at disentangling the role of constituent position and headedness, together with their possible interaction with semantic transparency. Methods A constituent priming paradigm was used in a lexical decision task. Transparent vs. opaque, and head-initial vs. head-final endocentric compounds were selected as probes; these were primed by either their initial or final constituents as compared to orthographically similar control primes. Results and Discussion Priming effect emerged with all types of compounds, indicating a direct access to the constituents independent of semantic transparency, constituent position and headedness. An interaction between these two latter factors emerged in the planned‐comparisons: priming the head causes larger facilitation than the modifier, but only in head-final compounds. This suggests that only the latter have hierarchical head‐modifier representations

Background: Several studies showed the positive effects of rhythm cueing on motor control in neurological disorders (hemiparesis, Parkinson disease). Yet, no studies were carried out on patients suffering from impaired programming of complex actions. Ideomotor apraxia is an ideal experimental paradigm to test the effect of rhythm on the reorganization of higher motor control after brain damage, since the impairment does not affect low-level motor control. Methods: A patient suffering from ideomotor apraxia has been tested before and after two rehabilitation training sets that only differed for the presence/absence of rhythmic cueing. Training was focused on the acquisition of novel complex motor sequences, and consisted in demonstrations and reproductions of target sequences by trials and errors. The ability to perform complex motor sequences was tested by considering the accuracy of limb-positions and trajectories along the path. Results: Both trainings increased the patient’s proficiency, but rhythmic cueing was significantly more effective, during the training (Chi2: p = .019) as well as during the post training uncued condition (t-test: p = .031). Discussion: Results are in line with neurophysiological data showing the effect of music on cognitive functions (Peterson & Thaut, 2007), and are discussed in the context of motor-control cognitive models.

Most studies on compound processing were performed in English and Dutch, languages that admit only head-final compounds: as a consequence, the effect of headedness might have been confounded with that of constituent position (but see [1]). Italian is ideally suited to address this issue, as Noun-Noun compounds can be either head-initial or head-final, with neither structure being clearly dominant over the other. The present study aims at disentangling the roles of semantic transparency, headedness and constituent position in the processing of Italian compound nouns. Thirty-two neurologically intact subjects participated in a priming experiment (SOA=300ms) with a lexical decision task. Forty-eight Noun-Noun compounds were selected as probes; they were either transparent or opaque (e.g., fotocopia, photocopy, vs boccaporto, hatch, lit. mouth+harbour) and head-initial or head-final (e.g., fotocopia vs capobanda, ring-leader, lit. chief+gang). The four groups of probes were matched for length, surface frequency and stem frequency. Each compound probe was primed by both its initial and its final constituent in separate runs; constituent primes were matched with orthographically similar control words (e.g., capo, chief vs. caso, chance) for length, surface frequency, stem frequency and orthographic neighbourhood. The ANOVA showed a first-level priming effect, with no significant interaction. The planned-comparison t-tests showed a facilitation effect with all types of compounds, which however is modulated by headedness and constituent position, i.e. there is no difference when the head or the modifier were primed in head-initial compounds, while the head elicited a greater effect in head-final compounds (see Figure). The presence of a priming effect with all kinds of targets suggests that constituents of Italian Noun-Noun compounds are automatically accessed, independently of semantic transparency, constituent position and headedness. However, the latter two factors do mo

Dual-route models of graphemic word processing have become paradigm cases for cognitive science and have been very successful in accounting for word and nonword reading and writing and their impairments. Although they were originally based on English, research has meanwhile been conducted on other languages and orthographies. Data are now available on several other European languages based on alphabetic scripts (French, German, and Italian), consonantal scripts (Hebrew), syllabic scripts (Japanese kana), and ideographic scripts (Chinese and Japanese kanji). Taken together, these studies point to the universality of two routes for reading, a lexical and a sublexical one, applying to nonalphabetic as well as alphabetic languages, and each route can be selectively impaired, thus suggesting their independent neural organization (Butterworth & Yin, 1991; Weekes, 2005). At the same time, neuroimaging studies of subjects in different alphabetic languages with a different degree of transparency between graphemes and phonemes suggest that a greater reliance on one or the other route depends on language-specific features (Paulesu et al., 2001). Given the similarity between languages with respect to the architecture of the model, future research can now focus on the role of specific differences.

Empirical evidence indicates that while the acquisition of oral language is based on neuroanatomical and functional units that are genetically predetermined, it is difficult to apply these assumptions to written language. This chapter pursues questions such as how reading and writing are represented at a mental level and how and where is it implemented in the human brain. In the first section the classical clinical neuropsychological taxonomy of reading and writing disorders is introduced and its limits discussed, while the second section deals with the contemporary models that describe normal written language processing and analyzes the implications of a more cognitively sound description of acquired dyslexia and dysgraphia. The third section provides an overview of the major cross-linguistic differences between languages, using alphabetic and logographic scripts and the impact these differences have on reading and spelling disorders. Finally, the neuroanatomical foundations of written language arising from both the anatomo-clinical correlative approach and functional neuroimaging studies are discussed.

We studied the effect of the target-to-distractor ratio (T/D) and short term memory on a matrix test performance. Higher performance on a visual search test with rising T/D ratio was found. An overall performance score improvement from the first to the third matrix is expected, because of the T/D ratio increase. In a previous study we found a significant difference on accuracy scores between the first and the following matrixes. In this article we demonstrate that an involvement of the short term memory processes could account for this result. Two hundred and twenty seven subjects from the Geriatric Unit of Ospedale Policlinico of Milan were considered. The subjects were 159 female and 68 male, aged 58 to 94 years with 3 to 18 years of education. Patients suffering from acute or chronic neurological diseases, sensorial impairment and alcoholism were excluded. We examined retrospectively the performance obtained by the subjects on a matrix test and a bisyllabic words span test. Correlation between accuracy scores obtained for the different matrixes of the attention test and the span score was then calculated. We found: 1) a significant difference on overall performance score between the three matrixes of the attention test: scores increase with the rise of T/D ratio; 2) a significant correlation between the accuracy score of the second and third matrix and the score of the span test; 3) no correlation between accuracy scores on the first matrix and the short-term memory score. In conclusion our data confirm the positive effect of a larger target-to-distractor ratio on the visual search performance in elderly people. The hypothesis that short-term memory is involved in the execution of the second and third matrix is preliminarly confirmed. The results are discussed in terms of the signal detection theory.

Bastiaanse and Jonkers (1998) found that in verb-impaired aphasic patients verb retrieval in picture naming tasks and in spontaneous speech do not always correlate. This study aims at (i) further investigating the relationship between verb production in formal tasks and spontaneous speech, (ii) extending this analysis to noun-specific impairments and (iii) using this evidence to clarify the cognitive damage underlying noun-verb dissociation. Seven Italian aphasic patients (three noun-impaired fluent, two verb-impaired fluent and two verb-impaired non-fluent patients) participated in the study. For each patient a three-hundred-word sample of spontaneous speech was analyzed. The number of tokens, types and roots was then calculated for any of these five categories: open-class words, closed-class words, nouns, open-class verbs and closed-class verbs. These variables were analyzed using the modified t-test described by Sokal and Rohlf (1995) and the norms reported in Semenza et al. (1989). Verb-impaired patients split according to the type of aphasia they suffer from; non-fluent patients have a poor verb-type production in spontaneous speech, while fluent patients produce a normal amount of verbs. Also noun-impaired fluent patients have a reduced noun production in spontaneous speech. We argue that this different behaviour depends on the different cognitive damages underlying the dissociations and on the different impact of the frame context characterizing spontaneous speech on noun and verb retrieval. The consequence of these results on the different hypotheses on noun-verb dichotomy mental representation will be also discussed.

The effect of grammatical class on semantic priming has been poorly investigated so far. In a first experiment we used primes and probes belonging to different grammatical classes (e.g., foodN-eatV) and no facilitation emerged. This result may be explained either semantically (structurally different semantic representations - i.e. functional vs visual, relational vs denotative- do not facilitate each other) or syntactically (i.e., no priming across grammatical classes). In a second experiment, we used strongly related noun-verb pairs in which prime and probe denote very close concepts (ideaN-thinkV): again, no priming emerged, suggesting that the semantic hypothesis is not correct. In a third experiment, we tested noun-noun and verb-verb pairs (dogN-catN; eatV-drinkV): semantic priming emerged with nouns (as usual), but not with verbs . Altogether, the experiments indicate that the mere presence of a verb in a prime-probe pair prevents semantic priming from emerging.

Objective: The objective of the study was to assess the accuracy and speed of matrix test performance, in aging. Methods: We tested a sample of 227 subjects, referring to the Geriatric Unit of Ospedale Policlinico of Milan. Subjects were 159 female and 68 male, aged from 58 to 94 years, with 3 to 18 years of education. We excluded patients with acute or chronic neurological disease, sensorial impairment and alcoholism. Data recorded were accuracy and speed of test performance according to new measures introduced. Results: The results show significant correlation between execution time and age, especially in second and third matrix. There is not significant correlation between the new accuracy measures of the three test matrix and age. Conclusions: We conclude that speed of matrix test performance decreases with aging, while the accuracy of execution remains stable. The study supports the hypothesis that visual attention is preserved in aging, and confirms a senile slowing. Normative data for the new measures of accuracy and speed of the matrix test performance are presented.