Raised line drawings are spontaneously explored with a single finger

In this study we examine the strategies used by blindfolded subjects asked to freely explore raised line drawings and identify what is depicted in them. We were particularly interested in how often a single finger is spontaneously used because in several studies subjects are forced to use only one fingertip and the extent to which this restriction may depress haptic perception is unclear. The results suggest that despite a variety of strategies, people 'naturally' use single fingertips sufficiently often to allow confidence in conclusions that are based on studies imposing this restriction.     

Strategic use of familiarity in display-based problem solving

The authors report 4 experiments that investigated the role of recognition memory and plausibility in a display-based problem-solving task (computer menu search). It was found that both the familiarity of options and their plausibility played a role in determining choices when the correct options could not be recollected. The use of familiarity was adaptive: Participants relied less on familiarity when it was a less valid guide to correct choices. The implications of these findings for theories of problem solving and learning are discussed.     

The constituent structure of autobiographical memory: autobiographical fluency in people with chronic epilepsy

A total of 59 people with chronic epilepsy recalled autobiographical episodes and personal facts (such as the names of friends or teachers) from various lifetime periods. Also tested was their verbal fluency and their fluency in generating items from semantic categories (animals, vegetables, US presidents, and British prime ministers). Results of a cluster analysis and a common factor analysis confirmed a dissociation between the retrieval of autobiographical information and that of nonpersonal semantic information. There was a similar dissociation between the recall of personal episodes and the recall of the personal information, but the corresponding factors were highly correlated with one another. Finally, verbal fluency performance was significantly correlated with the retrieval of personal information, personal episodes, and common objects, but not with that of public figures. The constituent structure of autobiographical fluency is extremely robust across different populations.     

Modification of magnitude estimations in thermotactile perception during self-generated and externally generated movements

Fourteen participants felt a 'cold' stimulus move across a fingertip. When movement was self-controlled, the stimulus was reported as feeling less 'cold' than when movement was externally generated.     

Phonological similarity neighborhoods and children’s short-term memory: Typical development and dyslexia

In this article, we explore whether structural characteristics of the phonological lexicon affect serial recall in typically developing and dyslexic children. Recent work has emphasized the importance of long-term phonological representations in supporting short-term memory performance. This occurs via redintegration (reconstruction) processes, which show significant neighborhood density effects in adults. We assessed whether serial recall in children was affected by neighborhood density in word and nonword tasks. Furthermore, we compared dyslexic children with typically developing children of the same age or reading level. Dyslexic children are held to have impaired phonological representations of lexical items. These impaired representations may impair or prevent the use of long-term phonological representations to redintegrate short-term memory traces. We report significant rime neighborhood density effects for serial recall of both words and nonwords, for both dyslexic and typically developing children.     

Looking to understand: the coupling between speakers' and listeners' eye movements and its relationship to discourse comprehension

We investigated the coupling between a speaker's and a listener's eye movements. Some participants talked extemporaneously about a television show whose cast members they were viewing on a screen in front of them. Later, other participants listened to these monologues while viewing the same screen. Eye movements were recorded for all speakers and listeners. According to cross-recurrence analysis, a listener's eye movements most closely matched a speaker's eye movements at a delay of 2 sec. Indeed, the more closely a listener's eye movements were coupled with a speaker's, the better the listener did on a comprehension test. In a second experiment, low-level visual cues were used to manipulate the listeners' eye movements, and these, in turn, influenced their latencies to comprehension questions. Just as eye movements reflect the mental state of an individual, the coupling between a speaker's and a listener's eye movements reflects the success of their communication.     

Effects of multiple exposures to D-cycloserine on extinction of conditioned fear in rats

Previous research has shown that an acute, post-training injection of D-cycloserine (DCS) facilitates extinction of conditioned fear in rats; however, the effects of multiple exposures to DCS in this situation are not known. In Experiment 1, rats were conditioned (light-shock pairings) and 24 h later given six extinction (light-alone) trials followed by an injection of DCS (15 mg/kg) or saline. The next day, all rats were tested for light-elicited freezing. In Experiment 2, the effect of DCS on extinction was tested in the same manner, except that rats were pre-exposed to DCS (0, 1, or 5 injections) just prior to conditioning. In Experiment 3, rats received five pre-exposures of DCS but conditioning occurred either 2 or 28 days after the last pre-exposure. The results showed that DCS facilitated extinction of conditioned freezing to the light CS when no drug pre-exposure had occurred, but pre-exposure to DCS just prior to conditioning disrupted the facilitation of extinction effect. When 28 days were interposed between pre-exposure and conditioning, the facilitatory effects of DCS on extinction were restored. These findings suggest that DCS has significant clinical value but that behavioral desensitization may occur with multiple exposures; however, desensitization is not permanent and is reduced by the passage of time.