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Reading impairment is an important feature in Primary Progressive Aphasia (PPA). The Spanish orthography entails completely regular spelling to sound correspondences, so reading disorders may be different to English. In the current study, reading, phonological and semantic abilities of 35 patients with the three variants of PPA, and 13 healthy volunteers were assessed. Brain metabolism was concomitantly obtained from each participant using 18 F-fluorodeoxyglucose positron emission tomography imaging. Two main patterns of impairment were identified: difficulties in nonwords reading with preservation of exception words in agrammatic and logopenic aphasia, and the inverse pattern in semantic dementia. Left frontal and left parietotemporal regions were associated to nonwords reading, while the anterior temporal lobe was related to reading of exception words. These results support the usefulness of examining reading abilities in the differential diagnosis of PPA variants, and suggest potential types of words that could be used in Spanish to assess these patients. [ABSTRACT FROM AUTHOR]

Abstract: Word-association tasks are considered useful tools to assess the normal functioning of the lexico-semantic system in healthy people and patients suffering from neurological disorders. Parkinson's Disease (PD) patients usually present some language dysfunction related to the functioning of the semantic system as a consequence of dopamine depletion. The aim of this study was to check if there were differences in the strength of association of the words generated by a group of non-demented PD patients on and off dopamine medication using a word-association task. In the study, 20 PD patients and 20 healthy-matched controls performed a word association task consisting of 10 nouns and 10 verbs matched by psycholinguistic variables. The participants were asked to generate the first word that came to mind given a specific single target. The results revealed that PD patients off medication said words less associated with the target compared with when they were on medication. Interestingly, comparisons between PD off patients and healthy controls revealed statistical differences only in response to verbs, while differences between PD on and controls were not found. Regarding nouns, we did not find any difference between PD off or PD on and healthy controls. This experiment adds more evidence to the assumption that the lexico-semantic system is disrupted in the absence of dopamine, resulting in poor spreading activation among associative words. [Copyright &y& Elsevier]

Abstract: Introduction: Parkinson’s disease (PD) is associated with dopamine depletion in the fronto-striatal network which affects some language aspects such as verb processing. Some experiments have demonstrated that dopamine deficiency plays a role in the normal functioning of the lexico-semantic system. As a result, the verbal fluency task could be a useful tool to assess the function of the semantic system, by examining both the number of words generated and the frequency of use of those words. Objective: The aim of this study was to find out how dopamine affects the performance of PD patients using a verbal fluency task, focussing on action-word fluency. Method: A group of 20 PD patients and 20 controls participated in the study. Participants were assessed with four different verbal fluency tasks: phonological, semantic (animal and supermarket words) and action fluency. PD patients were tested twice (on/off medication) and controls only once. Results: For the number of words, there were significant differences between PD patients on and off medication in the phonological and action fluency tasks. Compared to controls, PD off medication produced significantly fewer words in phonological, and actions. Regarding frequency, differences were found between PD patients off medication and controls for the action-word category. Discussion: Our data showed a specific deficit in PD patients off medication in categories mainly depending on frontal lobe function (phonological and actions) while these differences were restored with dopamine treatment. Moreover, PD patients off medication produced higher frequency verbs than controls, suggesting that dopamine affects the normal functioning within the lexico-semantic network of verbs. [Copyright &y& Elsevier]

Abstract: The aim of this study was to determine the brain areas responsible for the semantic impairment observed in Alzheimer’s disease (AD) and Mild Cognitive Impairment (MCI) patients. Thirteen AD, 14 MCI patients, and 13 matched healthy older adults were assessed with a test battery aimed to study their semantic competence. Different subtasks were designed to study their semantic knowledge related to objects and faces in the context of semantic retrieval- and semantic association-dependent tasks. Aggregate scores obtained in the different tests were entered into voxel-based regression analyses with grey matter volume values obtained from three-dimensional brain MRI scans. Areas of significant correlation between volume loss and poor semantic scores were restricted to the temporal lobe in the AD group, while in the MCI and control groups significant associations were found with lower grey matter volume values in a widely distributed network of bilateral fronto-temporo-parietal regions. Our results suggest that degradation of partially overlapping and widely distributed neural networks, mainly including temporal regions, subserve semantic deficits related to objects and faces in AD and MCI patients. [Copyright &y& Elsevier]

Abstract: Growing evidence supports the notion that the same brain areas involved in planning and execution of movements are also involved in verb processing. Recent studies have pointed out the existence of verb impairment in patients with Parkinson''s disease (PD), a neurodegenerative disorder typically characterized by motor disturbance related to dopamine deficiency in the nigrostriatal system. The aim of this study was to test the influence of dopaminergic treatment in a group of non-demented PD patients on the performance of action naming. The action pictures belonged to two categories: pictures with high and low degree of motor content. A group of 20 PD patients without dementia and 15 controls performed the task. PD patients were assessed twice, on and off medication, controls only once. A repeated measures ANOVA was carried out on the reaction times. The results showed a main effect of group and a significant interaction between group×motor content when comparing the three groups. When the comparison was made only on the PD groups (on vs. off medication) the interaction group×motor content was also significant, indicating that PD patients off medication had longer reaction times for pictures with a high degree of motor content compared to PD patients on medication. These results suggest a selective deficit in naming pictures associated with high motor content in PD patients without dopamine medication. This effect could be due to the relations between brain motor areas and verb processing associated with dopamine depletion. [Copyright &y& Elsevier]

Abstract: Purpose: Previous research has shown dementia and mild cognitive impairment to be present in some Parkinson''s disease (PD) patients. Nevertheless, it is still not clear whether PD patients are also impaired on facial emotion recognition, nor it is whether this possible deficit is independent other cognitive impairment. The aim of this study is to assess the presence of emotion recognition deficits in a sample of PD patients with normal cognitive abilities, evaluated with several cognitive tasks widely used to detect cognitive impairment in this patient group. Method: 40 non-demented (MMSE scores>25) PD patients and 19 healthy older adults matched on demographic characteristics took part in the study. All of them were evaluated with a neuropsychological battery including tests aimed to assess the cognitive domains mainly affected by PD, as well as a facial emotion recognition task. Results: t-test analysis showed significant differences between PD and control groups in 6 cognitive tasks which were introduced in a sequential logistic regression analysis. The results confirmed the existence of a facial emotion recognition deficit in PD patients after controlling for demographic and cognitive characteristics of the participants. Conclusion: Although none of the PD patients fulfilled criteria for dementia, many of them appeared to present deficits on recognition of facial emotions. This task should therefore be incorporated into future research to study the full range of early cognitive dysfunctions and non-motor symptoms presents in PD patients, and inclusion of this task in assessment protocols should be considered. [Copyright &y& Elsevier]

Abstract: Studies of word production in patients with Alzheimer''s disease have identified the age of acquisition of words as an important predictor of retention or loss, with early acquired words remaining accessible for longer than later acquired words. If, as proposed by current theories, effects of age of acquisition reflect the involvement of semantic representations in task performance, then some aspects of word recognition in patients with Alzheimer''s disease should also be better for early than later acquired words. We employed a version of the lexical decision task which we term the lexical selection task. This required participants to indicate which of four items on a page was a real word (the three ‘foils’ being orthographically plausible nonwords). Twenty-two patients with probable Alzheimer''s disease were compared with an equal number of matched controls. The controls made few errors on the test, demonstrating that the controls were cognitively intact, and that the words were familiar to participants of their age and level of education. The Alzheimer patients were impaired overall, and recognized fewer late than early acquired words correctly. Performance of the Alzheimer patients on the lexical selection task correlated significantly with their scores on the mini mental state examination. Word recognition becomes impaired as Alzheimer''s disease progresses, at which point effects of age of acquisition can be observed on the accuracy of performance. [Copyright &y& Elsevier]

Abstract: Objective: The main goal of the present study was to dissociate the effects on reading of frequency, age of acquisition (AoA) and imageability using the evoked response potential paradigm. Method: Twenty participants read words from three experimental conditions: high and low frequency, late and early age of acquisition and high and low imageability. Results: High frequency words produced more positive mean amplitude than low frequency words in the 175–360ms post-stimulus onset time window and late AoA produced more negative amplitudes than early AoA in the 400–610ms window. Imageability did not produce any effect in any time window tested. Brain electromagnetic tomography showed the most activated cortical areas for each category of stimuli. Conclusions: The lexical frequency of words seems to affect an early phase in the recognition process, perhaps at the level of the orthographic input lexicon, while AoA was observed at a later stage, indicating that this variable influence processing at a semantic level or at the links between semantics and phonology. Significance: EEG permits the researcher to investigate the time course, and approximate location in the brain, of psycholinguistic variables. [Copyright &y& Elsevier]

Abstract: Two Alzheimer''s patients participated in a longitudinal study of picture naming aimed at analysing the effect of lexical frequency, age of acquisition, stimulus familiarity, word length, name imageability, visual complexity and semantic category membership on naming success. The results were analysed with a new method [Capitani, E., & Laiacona, M. (2004). A method for studying the evolution of naming error types in the recovery of acute aphasia: A single-patient and single-stimulus approach. Neuropsychologia, 42, 613–623] that allows us to consider the consistency of responses to stimuli over repeated testing within clinical stages. The experiment was carried out as a longitudinal study of single cases, and the effect of each variable was estimated after removing the overlap with the other predictors. The semantic category of stimuli was not an influential factor for either patient. Other findings sharply distinguished between the two patients. In one case, disease-related decline consistently affected mainly late acquired names, whereas in the other case the decline affected names corresponding to low-familiarity items. To interpret this contrast, we further analysed the quality of the errors produced by each patient. This study shows that the psycholinguistic characteristics of a stimulus may exert varying influence in different patients, warranting further development of this line of inquiry. [Copyright &y& Elsevier]

Abstract: The aim of this work was to test whether the differences usually found between the processing of visual stimuli corresponding to natural and artifactual domains reflect the different ways in which these domains are organized in the brain or are rather due to varying tasks demands. For this purpose, we designed two tasks in which subjects had to classify a series of line drawings. In one task (semantic categorization), the subjects were asked to categorize the stimuli as corresponding either to the natural or the artifactual class, and in the other (gender decision), the subjects had to decide if the names of the stimuli corresponded to either the masculine or the feminine gender. Event-related potentials (ERPs) and reactions times (RTs) were registered during the two tasks. We found both quantitative and topographical differences between ERPs elicited by natural stimuli and those by artifactual stimuli. In the 50- to 200-ms period, ERPs were more positive for the natural stimuli in the categorization task, but more positive for the artifactual stimuli in the gender decision task. In addition, natural stimuli elicited larger P600 and were associated with shorter RTs than artifactual stimuli in the categorization task. These results likely reflect differences concerning the relative difficulty of processing the stimuli of each domain in each task. In the N400 range, in contrast, there were differences between the two domains which were independent of task. In the two tasks, natural and artifactual stimuli elicited ERPs with a different scalp distribution: ERPs were more positive at posterior (parietal and temporal) sites for the natural stimuli and in the frontal areas for the artifactual ones. This finding is consistent with the hypothesis that semantic knowledge associated with natural and artifactual domains is represented in separate subsystems with presumably different anatomical bases. [Copyright &y& Elsevier]

Abstract: Previous studies involving lexical access in anomic patients had employed regression analyses to separate the lexical variables. But it is now known that when the relevant variables are as closely related as frequency, age of acquisition (AoA), and familiarity, regression analysis loses efficacy. The aim of the present paper was to investigate which of these variables determines lexical access in anomic patients. In order to disentangle the effects of frequency from those of AoA, we conducted two picture-naming studies. In the first study, we used a semifactorial design in which we manipulated one variable and matched the other. In the second, we used an orthogonal factorial design in which the two variables were crossed to detect any interaction between them. The participants were pure anomic patients whose disorders affected lexical access exclusively; they had neither semantic nor phonological deficits. The statistical analyses show a clear effect of AoA, no effect of frequency, and no interaction between the two variables. The results of this study indicate that AoA is the main determinant of lexical access in anomic patients, and this must be taken into account in constructing materials for the assessment and rehabilitation of these patients. [Copyright &y& Elsevier]

Twenty Spanish patients with probable Alzheimer’s disease (AD) and 20 matched controls were given a battery of 17 tasks involving object recognition and the spoken and written perception and production of words and non-words. The AD patients were significantly impaired on nine of the tasks. Prominent among these were tasks that involve semantic processing, though non-word reading was also impaired. Performance on a category fluency task best discriminated AD patients from controls. It is proposed that impairment to semantic processing underlies most of the observed deficits on lexical processing tasks in patients with early AD, but that non-word reading may be sensitive to additional, mild impairments to phonological representations caused by extension of the degenerative process from anterior to posterior temporal regions. [Copyright &y& Elsevier]

Abstract Alzheimer's disease (AD) patients are known to present semantic memory impairments, and semantic processing plays a crucial role in the formation of false memories. We assessed 40 early stage AD patients and 35 matched healthy volunteers with an emotional version of the Deese-Roediger-McDermott paradigm, which allows the study of false memory formation. Participants were presented with three negative, three neutral and three positive lists of words, each semantically associated to a critical unpresented word. After the presentation of the lists the volunteers were asked to respond to a recognition questionnaire stating whether these critical lures, as well as other presented and unpresented words, had been previously shown or not. We replicate the pattern of decreased discriminability between list-related and -unrelated items for AD patients compared to healthy seniors observed in previous studies. Moreover, like control participants, AD patients displayed enhanced true recognition for emotional materials, both positive and negative. With regards to false recognition, our data show decreased discriminability between related and unrelated lures for positive material. These results point out differential involvement of semantic-based information during memory formation in AD patients compared to healthy seniors. Nevertheless, our data indicate that emotional content effects over semantic-based false memory formation persist in this population, at least at early stages of disease development. Highlights • Alzheimer's disease patients present semantic memory impairments. • Valence affects false memory formation in healthy adults. • Early-stage AD patients and matched controls were presented with valenced DRM lists. • AD patients presented reduced discriminability for true and false recognition. • Valence still affects semantic-based false memories in early-stage AD patients. [ABSTRACT FROM AUTHOR]

Abstract The impact of central on peripheral writing processes has been studied mainly in adults and children whose first language is a deep orthographic system. The results suggest that the influence varies according to age, but it also could depend on the orthographic system. The objective of the present work was to address the possible impact of the central (orthographic retrieval) on peripheral (motor execution) processes during writing acquisition in a transparent orthography. To achieve the objective, seventy-five Spanish children performed a copying and a spelling-to-dictation task, where orthographic consistency, lexical frequency and word length were manipulated. The results suggest that the central processes influence the peripheral ones from an early age (when writing has not yet been automated). Specifically, orthographic consistency cascaded into movement production, but it was modulated by task and grade, as this effect was only evident for 2nd grade children when they were asked to perform a spelling-to-dictation task. [ABSTRACT FROM AUTHOR]

The syntactic skills of Spanish-speaking children with Williams syndrome (WS) were assessed in different areas (phrase structure, recursion, and bound anaphora). Children were compared to typically-developing peers matched either in chronological age (CA-TD) or in verbal age (VA-TD). In all tasks children with WS performed significantly worse than CA-TD children, but similarly to VA-TD children. However, significant differences were observed in specific domains, particularly regarding sentences with cross-serial dependencies. At the same time, children with WS were less sensitive to syntactic constraints and exhibited a poorer knowledge of some functional words (specifically, of nonreflexive pronouns). A processing bottleneck or a computational constraint may account for this outcome. [ABSTRACT FROM AUTHOR]

Abstract: Behavioral measures in visual priming tasks show opposite effects for syllables and morphemes, which indicate that they are processed by two independent systems. We used event related potentials (ERPs) to explore two priming situations in Spanish: prefix related words (reacción-REFORMA [reaction-reform]), in which prime and target words shared a first syllable that was also a prefix, and syllable related words (regalo-REFORMA [gift-reform.]), in which the shared first syllable was a pseudoprefix in the prime word. Prefix related pairs, unlike syllable related pairs, evoked a very early positivity in reaction to the target (at 150–250ms window), suggesting that the prefix information is immediately available, at a prelexical stage. By contrast, syllable related pairs showed a larger N400 effect. This late negativity may be caused by lateral inhibition among lexical candidates activated in the lexicon by the prime''s first syllable. [Copyright &y& Elsevier]

• Handwriting speed does not develop at the same pace as graphic speed. • Handwriting speed is independent of graphic speed by the age of 12. • Lexicality and word length did not affect writing durations in children aged 8-12. • Spanish 8-12-year-olds use both lexical and sublexical information to spell. The present study addresses how handwriting speed increases with age among Spanish 8-, 10- and 12-year-old children (n = 60), and how this progression is related to spelling and more general graphic skills. Handwriting speed was measured in a spelling-to-dictation and a copying task, and graphic speed was measured in a trail tracing task. Results revealed that handwriting speed significantly increased from age 8 to 10 and remained stable up to 12 years of age, while graphic speed substantially increased only between 10 and 12 years of age. Thus, handwriting speed and graphic speed do not seem to follow the same pattern of development. Moreover, the relationship between linguistic processes and graphic skills with handwriting speed was not the same for all the groups. In the younger group, a different speed profile was obtained for each task, while in the groups of 10- and 12-year-olds, speed was similar in all the linguistic tasks. Graphic speed was positively correlated with speed in the spelling task only around the age of 10, and by age of 12 graphic speed correlated negatively when handwriting neatness was prioritized. Altogether, these results show that handwriting speed becomes consistent around the age of 10, when it is mostly affected by spelling ability and, in some circumstances, by graphic speed. By the age of 12, speed in linguistic tasks becomes decoupled from graphic speed and it is adapted depending on the relative importance of neatness and speed for the task. [ABSTRACT FROM AUTHOR]

The human motor cortex is involved in the planning and execution of movements as well as in the processing of action language, and it is impaired in Parkinson's disease (PD) as a consequence of dopamine degeneration. The aim of this study is to understand the role of dopamine in the processing of action words by looking at PD patients with and without medication. A group of 23 healthy controls and 34 non-demented PD patients participated in an action verbal fluency task on and off dopamine medication. A repeated measures 2 × 2 ANOVA was conducted with dopamine (on/off) and type of verb (high and low specificity motor verbs) as independent variables and the number of words generated as a dependent variable. Our results showed that patients on dopamine medication produced a significantly greater number of high specificity motor verbs than low ones. In contrast, patients off dopamine medication generated a similar number of verbs with high and low motor specificity. MANOVA analyses showed a significantly lower production of verbs with high motor specificity on PD patients off medication compared to healthy controls. However, performance of PD patients in the on condition was similar to that found in healthy controls. In conclusion, the dopamine network from basal ganglia to brain motor areas might play a role in retrieving action verbs with specific semantic representations. [ABSTRACT FROM AUTHOR]

Abstract: In order to explore the possible contribution of the motor system to the representation of verbs, we studied the relative preservation of the capacity of Parkinson disease patients to name matched sets of object and action pictures. The performance of this group of participants was compared with that of a group of healthy seniors, and a group of Alzheimer disease patients. Generalized linear mixed-effects analyses showed that, whereas the two control groups had similar accuracy scores in response to objects and actions, Parkinson disease patients presented a significant impairment in their capacity to name actions compared to objects. The results of this study support the idea that verb representations are grounded in neural networks to which brain areas involved in motor control contribute. [Copyright &y& Elsevier]

Abstract: We investigated picture naming in Spanish-speaking patients with probable Alzheimer''s disease using coloured line drawings of actions and objects matched on several key psycholinguistic variables. The patients were less accurate than healthy controls but we found no significant evidence for an effect of grammatical class. Generalized linear mixed-effects analyses indicated that patient naming accuracy was affected by lexical frequency and age of acquisition, and by the name agreement of the pictures. These observations support the view that, while the effect of grammatical class is not an important influence, accurate picture naming in dementia is determined by the impact of lesions on a lexico-semantic mapping structured by experience. [Copyright &y& Elsevier]