A lexical decision experiment was conducted while event related potentials (ERPs) were recorded. The word frequency and the first syllable frequency of each word were manipulated. Results showed that, while high frequency words produced less negative amplitudes in the N400 time window than low frequency words, the inverse pattern was found for syllable frequency.
View Article and Find Full Text PDFThe synthesis and the biological activity of compounds 5-40 as inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), as well as modulators of voltage-dependent Ca(2+) channels and nicotinic receptors, are described. These molecules are tacrine analogues, which have been prepared from polyfunctionalized 6-amino-5-cyano-4H-pyrans, 6-amino-5-cyano-pyridines and 5-amino-2-aryl-3-cyano-1,3-oxazoles via Friedländer reaction with selected cycloalkanones. These compounds are moderate acetylcholinesterase and butyrylcholinesterase inhibitors, the BuChE/AChE selectivity of the most active molecules ranges from 10.
View Article and Find Full Text PDFMini Rev Med Chem
September 2003
The acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities of a series of pyrano[2,3-b]quinolines (2, 3), [1,8]naphthyridines (5, 6), 4-amino-2,3-diaryl-5,6,7,8-tetrahydrofuro[2,3-b]quinolines (11-13)/ 4-amino-6,7,8,9-tetrahydro-2,3-diphenyl-5H-cyclohepta[e]furo[2,3-b]pyridine (14), 4-amino-5,6,7,8-tetrahydro-2,3-diphenylthieno[2,3-b]quinoline (15)/ 4-amino-6,7,8,9-tetrahydro-2,3-diphenyl-5H-cyclohepta[e]thieno[2,3-b]pyridine (16) are described. These compounds are tacrine analogues that have been prepared from readily available polyfunctionalized ethyl [6-amino-5-cyano-4H-pyran]-3-carboxylates (9, 10), ethyl [6-amino-5-cyanopyridine]-3-carboxylates (7, 8), 2-amino-3-cyano-4,5-diarylfurans (17-19) and 2-amino-3-cyano-4,5-diphenylthiophene (20) via Friedländer condensation with selected ketones. These compounds are competitive and, in a few cases, non-competitive inhibitors for AChE, the most potent being compound (14), though three-fold less active than tacrine.
View Article and Find Full Text PDFThe aim of the current study was to explore the integration processes of gender and number morphological features, since it has been proposed that grammatical gender and number features might be associated with different strength with the word stem in lexical representation. Event related potentials (ERPs) were recorded using a 128-channel sensor net while twenty-four volunteers read Spanish word pairs and performed a syntactic judgment task. The word pairs which could agree or disagree in gender or number or in gender and number at the same time, were formed by a noun and an adjective (e.
View Article and Find Full Text PDFTwo lexical decision experiments were conducted to determine whether there is a specific, localized influence of the item frequency of consecutive trials (i.e., first-order sequential effects) when the trials are not related to each other.
View Article and Find Full Text PDFProblem: To clarify the possible influence of human leukocyte antigen (HLA) mother-child genotypes and human cytomegalo virus (HCMV) presence on the development of preeclampsia.
Methods Of Study: One hundred and four DNA samples from mothers with preeclampsia, mothers with a normal history of pregnancies and their neonates were tested by polymerase chain reaction-sequence specific oligonucleotide probes (PCR-SSOP) for HLA-A, -G, -DRB1, -DQA1, -DQB1 alleles. The HCMV sequences were analyzed using a PCR-SSOP method and the four primers described by Chou (Chou S: J Clin Microb 1992; 30:2307-2310).
J Exp Psychol Hum Percept Perform
October 2002
Four lexical decision experiments using a masked priming paradigm were conducted to analyze whether the previous presentation of a syllabic neighbor (a word sharing the same 1st syllable) influences recognition performance. The results showed an inhibitory effect of more frequent syllabic primes and some facilitation of nonword syllabic primes (Experiments 1-3). When monosyllabic pairs were used (Experiment 3), no priming effects of the 2 initial letters were found.
View Article and Find Full Text PDFThe acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibition activities of a series of 4-amino-2, 3-diaryl-5, 6, 7, 8-tetrahydrofuro[2, 3-b]quinolines (10-12)/4-amino-5, 6, 7, 8-tetrahydro-2, 3-diphenylthieno[2, 3-b]quinoline (14) and 4-amino-5, 6, 7, 8, 9-pentahydro-2, 3-diphenylcyclohepta[e]furo[2, 3-b]pyridine (13)/4-amino-5, 6, 7, 8, 9-pentahydro-2, 3-phenylcyclohepta[e]thieno[2, 3-b]pyridine (15) are described. These compounds are tacrine (THA) analogues which have been prepared either from readily available 2-amino-3-cyano-4, 5-diarylfurans (16-18) or from 2-amino-3-cyano-4, 5-diphenylthiophene (19), via Friedländer condensation with cyclohexanone or cycloheptanone. These compounds are competitive inhibitors for acetylcholinesterase, the more potent being compound (13) which is three-fold less active than tacrine.
View Article and Find Full Text PDFIn an eye movement experiment, we examined the use of reanalysis strategies during the reading of locally ambiguous but globally unambiguous Spanish sentences. Among other measures, we examined regressive eye movements made while readers were recovering in reading mild garden path sentences. The sentences had an adverbial clause that, depending on the mood (indicative vs.
View Article and Find Full Text PDFObjective: Determination of Ca-ATPase activity and thiobarbituric acid-reactive substances (TBARS) of red cell ghosts from neonatal and maternal blood of normotensive and preeclamptic women.
Methods: Venous blood was obtained by venipuncture of six nulliparous normotensive and six preeclamptic pregnant women. After cesarean delivery, blood samples were obtained from the umbilical cord of the same patients.
A new series of tacrine (9-amino-1,2,3,4-tetrahydroacridine) derivatives were synthesized and their effects on 45Ca(2+) entry into bovine adrenal chromaffin cells stimulated with dimethylphenylpiperazinium (DMPP) or K(+), studied. At 3 microM, compound 1 did not affect (45)Ca(2+) uptake evoked by DMPP. Compounds 14, 15 and 17 inhibited the effects of DMPP by 30%.
View Article and Find Full Text PDFEye fixations were recorded to assess whether, how, and when readers draw inferences about predictable events. Predicting context sentences, or non-predicting control sentences, were presented, followed by continuation sentences in which a target word referred to a predictable event (inferential word) or an unlikely event (non-predictable word). There were no effects on initial target word processing measures, such as launch and landing sites, fixation probability, first-fixation duration, or first-pass reading time.
View Article and Find Full Text PDFThe synthesis and preliminary results for acetylcholinesterase and butyrylcholinesterase inhibition activity of a series of pyrano[2,3-b]quinolines (2, 3) and benzonaphthyridines (5, 6) derivatives are described. These molecules are tacrine-like analogues which have been prepared from readily available polyfunctionalized ethyl [6-amino-5-cyano-4H-pyrans and 6-amino-5-cyanopyridines]-3-carboxylates via Friedlander condensation with selected ketones. These compounds showed moderate acetylcholinesterase inhibition activity, the more potent (2e, 5b) being 6 times less active than tacrine.
View Article and Find Full Text PDFJ Exp Psychol Learn Mem Cogn
March 2001
Three types of sublexical units were studied in Spanish visual word recognition: the syllable, the basic orthographic syllabic structure (BOSS), and the root morpheme. In Experiment 1, using a lexical-decision task, a typical inhibitory effect of the first-syllable frequency was found (while keeping constant the BOSS frequency) as well as the word-frequency effect. Experiment 2 examined the role of both the BOSS frequency and the word frequency, also in a lexical-decision task.
View Article and Find Full Text PDFWe determined Na,K-ATPase activity and cholesterol/phospholipid ratio of maternal and cord red blood cell ghosts from either normotensive or preeclamptic pregnant women. The Na,K-ATPase activity of the red cell ghosts from neonatal blood is significantly lower (25-32%) as compared with the ATPase activity of the maternal red cell ghosts, regardless of the presence or not of preeclampsia. This diminution in Na,K-ATPase activity of the neonatal red blood cell ghosts could be due to an increase in the cholesterol/phospholipid molar ratio of the membrane.
View Article and Find Full Text PDFMem Cognit
September 1999
Ambiguity as to what the relative clause modifies in phrases such as Someone shot the maid of the actress who was divorced/Alguien disparó contra la criada de la actriz que estaba divorciada tends to be resolved differently in different languages (and in different forms of complex noun phrases). In English, there is a weak but seldom significant tendency for the relative clause to be taken as modifying the second noun phrase, the actress, but in Spanish, several researchers have found a significant preference for the relative clause's modifying the first noun phrase, la criada. The present experiments compare Spanish and English readers' eye movements while reading exactly comparable sentences in their native languages and find a significant reading time advantage in Spanish when it is forced to modify the first noun phrase, but in English when the relative clause is forced to modify the second noun phrase.
View Article and Find Full Text PDFIn three experiments, we explored the role of verb tense and verb aspect in subjects' construction of mental models while reading. In the first and second experiments, subjects read paragraphs in which verb tense was manipulated to assign current and past attributes (job descriptions) to a main character. The results showed that on-line accessibility was faster for current attributes.
View Article and Find Full Text PDFJ Exp Psychol Learn Mem Cogn
July 1997
Effects of orthographic neighborhood in visual word recognition in Spanish were examined in 5 paradigms: progressive demasking, standard lexical decision, lexical decision with blocking of neighborhood density, naming, and semantic categorization. The results showed inhibitory effects of neighborhood frequency in the progressive-demasking task, in both lexical-decision tasks, as well as for low-density words in the naming task, and for high-density words in the semantic-categorization task. Higher levels of neighborhood density produced an inhibitory trend in the progressive-demasking task, facilitation in lexical decision (significant only when neighborhood density was blocked), and a robust facilitation effect in naming (only for words with higher frequency neighbors).
View Article and Find Full Text PDFFour experiments were carried out to investigate how general knowledge about the stereotypical gender of participants in a text influences comprehension. A self-paced reading task was used to present short texts comprising one, two, or three sentences. The first sentence of each text introduced a stereotypically masculine or feminine participant (e.
View Article and Find Full Text PDFAn advantage of first mention-that is, faster access to participants mentioned first in a sentence-has previously been demonstrated only in English. We report three experiments demonstrating that the advantage of first mention occurs also in Spanish sentences, regardless of whether the first-mentioned participants are syntactic subjects, and regardless, too, of whether they are proper names or inanimate objects. Because greater word-order flexibility is allowed in Spanish than in English (e.
View Article and Find Full Text PDFFive experiments measured reading time for Spanish and English sentences containing a complex NP followed by a relative clause (e.g., .
View Article and Find Full Text PDFThe aim of this research is to explore whether comprehension is impaired by test anxiety, whether the anxious person spends compensatory reading time, and which cognitive processes are affected. High- and low-anxiety students read texts word by word with the moving-window technique under test conditions. Multiple regression analyses on word-reading times were computed with a number of psycholinguistic variables--assumed to map onto specific processes--serving as predictors.
View Article and Find Full Text PDFThis paper examines the mechanisms involved in the assignment of an antecedent to an anaphoric element. In general, pronouns must match their antecedents at least with respect to number and gender. Sensitivity to such constraints has been shown in several experiments.
View Article and Find Full Text PDFThe study tested the hypothesis that east-west is more difficult to discriminate than north-south because pre-experimentally the former is associated with right-left and the latter with up-down (or front-behind). Forty-eight undergraduates first learned north, south, east, and west in slides of unknown places. In one condition the compass directions were indicated by labels.
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