Carmen Noguera

Attentional orienting within visual field in a lexical decision task

The influence of spatial attention on lexical decisions to lateralized target letter-strings appearing either along with a distractor (Experiment 1) or in an otherwise empty field (Experiments 2-6) was examined. Attentional orienting was controlled by peripheral (Experiments 1, 2, 3, and 6) and central (Experiments 4-5) cuing methods. Manipulations of spatial attention, including cue validity and cue-target stimulus onset asynchrony, were combined with manipulations of word frequency in Experiments 3-6. All the attentional manipulations were effective, but they did not modify the right visual field advantage in word performance. In addition, the attentional effects did not interact with either the presence or absence of distractors or with stimulus familiarity. Implications of these results regarding the influence of spatial attention (the posterior attention system) on word processing are discussed.

Individual Differences in Working Memory Capacity Modulates Semantic Negative Priming from Single Prime Words

The present study investigated whether semantic negative priming from single prime words depends on the availability of cognitive control resources. Participants with high vs. low working memory capacity (as assessed by their performance in complex span and attentional control tasks) were instructed to either attend to or ignore a briefly presented single prime word that was followed by either a semantically related or unrelated target word on which participants made a lexical decision. Individual differences in working memory capacity (WMC) mainly affected the processing of the ignored primes, but not the processing of the attended primes: While the latter produced reliable positive semantic priming for both high- and low-WMC participants, the former gave rise to reliable semantic negative priming only for high WMC participants, with low WMC participants showing the opposite positive priming effect. The present results extend previous findings in demonstrating that (a) single negative priming can reliably generalize to semantic associates of the prime words, and (b) a differential availability of cognitive control resources can reliably modulate the negative priming effect at a semantic level of representation.

Temperament and negative semantic priming in children 7 to 12 years old.

The present research assessed whether children with high and low scores on temperament traits differed in their ability to inhibit irrelevant task information in a lexical decision task. Children from 7 to 12 years old were classified based on temperament dimensions measured using a version of the Temperament in Middle Childhood Questionnaire. The participants were instructed to either attend to (and remember) or to ignore a masked prime word followed by a central probe target on which they made a lexical decision. The results revealed several notable outcomes. First of all, recognition memory was better for attended than ignored words, providing further evidence that attention instructions influenced the processing of the primes. Secondly, although no negative priming effect was obtained in the “ignore” condition, 43% of children showed this effect. Thirdly, children scoring high on Inhibitory Control and Impulsivity showed ignored negative priming, whereas children scoring high on Inhibitory Control and low on Impulsivity ignored facilitation. Data are discussed within the framework of negative priming as a complex phenomenon that involves the interaction of different factors such as age, type of task, and certain temperament traits.

The Influence of Working Memory Load on Expectancy-Based Strategic Processes in the Stroop-Priming Task

The present study investigated whether a differential availability of cognitive control resources as a result of varying working memory (WM) load could affect the capacity for expectancy-based strategic actions. Participants performed a Stroop-priming task in which a prime word (GREEN or RED) was followed by a colored target (red vs. green) that participants had to identify. The prime was incongruent or congruent with the target color on 80 and 20% of the trials, respectively, and participants were informed about the differential proportion of congruent vs. incongruent trials. This task was interleaved with a WM task, such that the prime word was preceded by a sequence of either a same digit repeated five times (low load) or five different random digits (high load), which should be retained by participants. After two, three, or four Stroop trials, they had to decide whether or not a probe digit was a part of the memory set. The key finding was a significant interaction between prime-target congruency and WM load: Whereas a strategy-dependent (reversed Stroop) effect was found under low WM load, a standard Stroop interference effect was observed under high WM load. These findings demonstrate that the availability of WM is crucial for implementing expectancy-based strategic actions.

High and low schizotypal female subjects do not differ in spatial memory abilities in a virtual reality task

Introduction. Schizotypy is a psychological construct related to schizophrenia. The exact relationship between both entities is not clear. In recent years, schizophrenia has been associated with hippocampal abnormalities and spatial memory problems. The aim of this study was to determine possible links between high schizotypy (HS) and low schizotypy (LS) and spatial abilities, using virtual reality tasks. We hypothesised that the HS group would exhibit a lower performance in spatial memory tasks than the LS group. Methods. Two groups of female students were formed according to their score on the ESQUIZO-Q-A questionnaire. HS and LS subjects were tested on two different tasks: the Boxes Room task, a spatial memory task sensitive to hippocampal alterations and a spatial recognition task. Results. Data showed that both groups mastered both tasks. Groups differed in personality features but not in spatial performance. These results provide valuable information about the schizotypy–schizophrenia connections. Conclusion. Schizotypal subjects are not impaired on spatial cognition and, accordingly, the schizotypy–schizophrenia relationship is not straightforward.