Sounds, words, sentences: age-related changes across levels of language processing

Age-related changes in sensory, lexical, and sentence processing were examined and compared using event-related potentials (ERPs) recorded as young and elderly participants listened to natural speech for comprehension. Lexically associated and unassociated word pairs were embedded in meaningful or syntactically legal but meaningless sentences. Early, general sensory, and attention-related responses (N1, P2) were delayed by about 25 ms for older participants, but later components indexing semantic processing (N400) were not delayed. There were no differences in the size, timing, or distribution of lexical associative effects for the two groups. In contrast, message-level context effects were delayed by more than 200 ms in the elderly group. The results support models that posit age-related changes primarily in higher order language processes.     

Reading between the lines: Event-related brain potentials during natural sentence processing

Event-related potentials (ERPs) were recorded from subjects as they silently read 160 different seven-word sentences, presented one word at a time. Each sentence was in itself a natural, meaningful phrase. Substantial intersubject variability was observed in the ERP waveshapes following the words. More than half of the subjects generated P3 components to word stimuli, but those who did showed similar responses to repeated control presentations of a single word. In addition, it was found that all but the first word in the sentence elicited an ERP with a significant left-greater-than-right asymmetry in the late positivity over temporo-parietal regions. The ERPs to the last words were associated with more late positivity than those to the preceding words. One quarter of the sentences, at random, ended with a word printed in a typeface that was different from that of the preceding words. This infrequent change in typeface elicited a complex ERP having three consistent late positive components.     

Differentiation of retinal and nonretinal contributions to averaged evoked responses obtained with electrodes placed near the eyes

Recent visual evoked potential (VEP) studies suggest that during sustained voluntary attention, irrelevant or unattended visual stimuli may be filtered precortically. Testing of this hypothesis in humans requires knowledge of the origin of specific components of the VEP that are affected by selective attention. This study describes techniques and procedures for distinguishing between retinal and nonretinal components of VEPs recorded from electrodes placed strategically around the eyes and on the forehead. By visually stimulating one eye at a time while recording simultaneously from both, and by stimulating a given retinal area with the eyes fixated on the target at different angular deviations from the normal line of regard, components of the VEPs around the eyes can be distinguished as of retinal or nonretinal origin. The results are discussed in terms of volume conduction theory.     

The suppression of reflexive visual and auditory orienting when attention is otherwise engaged

Two experiments were conducted to examine whether abrupt onsets are capable of reflexively capturing attention when they occur outside the current focus of spatial attention, as would be expected if exogenous orienting operates in a truly automatic fashion. The authors established a highly focused attentional state by means of the central presentation of a stream of visual or auditory characters, which participants sometimes had to monitor. No intramodal reflexive cuing effects were observed in either audition or vision when participants performed either an exogenous visual or auditory orthogonal cuing task together with the central focused attention task. These results suggest that reflexive unimodal orienting is not truly automatic. The fact that cuing effects were eliminated under both unimodal and cross-modal conditions is consistent with the view that auditory and visual reflexive spatial orienting are controlled by a common underlying neural substrate.     

MONITORING CONSCIOUS RECOLLECTION VIA THE ELECTRICAL ACTIVITY OF THE BRAIN

Abstract— Although another person's experience of recollection cannot be observed directly, we have found that the underlying operations can be monitored using noninvasive electrophysiological techniques. Results from two experiments showed that brain potentials elicited 500 to 900 ms after the onset of visually presented words vary systematically in amplitude with manipulations that influence the extent to which subjects engage in recollective processing. These brain potentials can thus be construed as correlates of the subjective experience of recollection     

Ground and Free-Variable Tableaux for Variants of Quantified Modal Logics

In this paper we study proof procedures for some variants of first-order modal logics, where domains may be either cumulative or freely varying and terms may be either rigid or non-rigid, local or non-local. We define both ground and free variable tableau methods, parametric with respect to the variants of the considered logics. The treatment of each variant is equally simple and is based on the annotation of functional symbols by natural numbers, conveying some semantical information on the worlds where they are meant to be interpreted.This paper is an extended version of a previous work where full proofs were not included. Proofs are in some points rather tricky and may help in understanding the reasons for some details in basic definitions.     

Compatible Functions in Algebras Associated to Extensions of Positive Logic

In [4], Caicedo and Cignoli study compatible functions on Heytingalgebras and the corresponding logical properties of connectivesdefined on intuitionistic propositional calculus. In this paperwe study some aspects of compatible functions on the algebrasassociated to positive propositional calculus and successiveextensions of it: intuitionistic calculus itself, the modalsymmetric propositional calculus of Moisil and n-valued ukasiewiczpropositional calculus.     

Psychometric properties of Spanish version of the Mini-Mental Adjustment to Cancer Scale

Background/ObjectiveThe aim of the study was to examine the factor structure and psychometric properties of the Spanish version of the Mini-Mental Adjustment to Cancer Scale (Mini-MAC) in a large sample of patients with non-metastatic, resected cancer.MethodsProspective, observational, multicenter study for which 914 patients were recruited from 15 Spanish hospitals. Exploratory and confirmatory factor analyses, validity and reliability analyses were conducted.ResultsFactor-analytic results indicated a 4-factor structure of the Spanish version of the Mini-MAC. Three subscales have psychometric properties similar to those of Helplessness, Anxious preoccupation, and Cognitive avoidance of the original the Mini-MAC. The Fighting spirit and the Fatalism subscales were combined on the Positive attitude scale. The four factor-derived scale scores exhibited acceptable accuracy for individual measurement purposes, as well as stability over time in test-retest assessments at 6 months. Validity assessments found meaningful relations between the derived scale scores, and Brief Symptom Inventory depression and anxiety scores and Functional Assessment of Chronic Illness Therapy spiritual well-being scores.ConclusionsThe Spanish version of the Mini-MAC provides reliable and valid measures for patients with non-metastatic, resected cancer, and results corroborate the instrument’s cross-cultural validity.