Biomedical subjects

Fernando Cuetos

Publications and source records attributed to Fernando Cuetos.

8 recordsLinked to original sources

PubMed2006

Event related potentials reveal differences between morphological (prefixes) and phonological (syllables) processing of words.

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.

Adolescent↗

PubMed2006

Determinants of lexical access in speech production: role of word frequency and age of acquisition.

The main determinants of lexical access in speech are considered to be a word's age of acquisition (AoA) and its frequency of occurrence in a speaker's experience. It is unclear whether and how these variables interact, although they are commonly observed to be correlated, for the few studies that address the issue have reported inconsistent findings. An influential view of AoA in lexical processing (Ellis and Lambon Ralph, 2000) predicts stronger frequency effects for items acquired later in life than for those acquired at an early age. Five experiments were designed to investigate the possible interaction of AoA and frequency effects in speech. We found that the interaction between word frequency and AoA was not robust and that, contrary to expectation, the effect of word frequency was greater for words acquired earlier in life than for those acquired later. The implications of our findings are discussed.

Age Factors↗

PubMed2005

Electrophysiological evidence for a natural/artifactual dissociation.

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.

Adult↗

PubMed2005

Acquired dyslexia in Spanish: a review and some observations on a new case of deep dyslexia.

Readers and writers of Spanish use an orthography that is highly transparent. It has been proposed that readers of Spanish can rely on grapheme-phoneme correspondences, alone, to access meaning or phonology from print. In recent years, a number of case studies have yielded evidence inconsistent with this idea. We review these studies with particular focus on those that report evidence for reading based on direct lexical mappings between print, orthographic representations, and meaning or phonology. We report a new case of acquired literacy impairment in Spanish, MJ, who presents a pattern of preserved abilities and deficits symptomatic of deep dyslexia. The patient is unable to read nonwords, but can read a substantial number of words. Her reading is characterized by the production of semantic, visual, and derivational errors. We argue that MJ has a deficit in her lexical selection ability, common to both her reading and her naming problems. We propose that MJ, and the other cases we review, demonstrate that lexical reading is adopted by skilled readers even in a transparent language.

Adult↗

PubMed2003

Lexical processing in Spanish patients with probable Alzheimer's disease.

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.

Aged↗

PubMed2003

The number 747 is named faster after seeing Boeing than after seeing Levi's: Associative priming in the processing of multidigit Arabic numerals.

Two experiments are reported in which naming multidigit Arabic numerals was shown to depend on the context in which the numbers were presented. Number naming and number decisions were faster after an associative prime (e.g., 747 preceded by the word Boeing) than after an unrelated prime, both in unmasked and masked priming conditions. On the basis of these findings, we conclude that number naming is not always based on a quantity-based semantically mediated pathway.

Adult↗

PubMed2003

Normative data and naming times for action pictures.

The present article provides Spanish norms for name agreement, printed word frequency, word compound frequency, familiarity, imageability, visual complexity, age of acquisition, and word length (measured by syllables and phonemes) for 100 line drawings of actions taken from Druks and Masterson (2000). In addition, through a naming-time experiment carried out with a group of 54 Spanish students in a pool of 63 of these line drawings, we determined the best predictors of naming actions. In the multiple regression analysis, age of acquisition and name agreement emerged as the most important determinants of action-naming reaction time.

Adolescent↗

PubMed2002

Aphasic naming in Spanish: predictors and errors.

Sixteen Spanish aphasic patients named drawings of objects on three occasions. Multiple regression analyses were carried out on the naming accuracy scores. For the patient group as a whole, naming was affected by visual complexity, object familiarity, age of acquisition, and word frequency. The combination of variables predicted naming accuracy in 15 of the 16 individual patients. Age of acquisition, word frequency, and object familiarity predicted performance in the greatest number of patients, while visual complexity, imageability, animacy, and length all affected performance in at least two patients. High proportions of semantic and phonological errors to particular objects were associated with objects having early learned names while high proportions of no-response errors were associated with low familiarity and low visual complexity. It is suggested that visual complexity and object familiarity affect the ease of object recognition while word frequency affects name retrieval. Age of acquisition may affect both stages, accounting for its influence in patients with a range of different patterns of disorder.

Adult↗