The old and thee, uh, new: disfluency and reference resolution

Most research on the rapid mental processes of on-line language processing has been limited to the study of idealized, fluent utterances. Yet speakers are often disfluent, for example, saying "thee, uh, candle" instead of "the candle." By monitoring listeners' eye movements to objects in a display, we demonstrated that the fluency of an article ("thee uh" vs. "the") affects how listeners interpret the following noun. With a fluent article, listeners were biased toward an object that had been mentioned previously, but with a disfluent article, they were biased toward an object that had not been mentioned. These biases were apparent as early as lexical information became available, showing that disfluency affects the basic processes of decoding linguistic input.     

An examination and replication of the psychometric properties of the Massachusetts Youth Screening Instrument--second edition (MAYSI-2) among adolescents in detention settings

There is a high prevalence of psychological disorders among adolescents in detention facilities. The need for a simple, effective screening tool led to the development of the Massachusetts Youth Screening Instrument (MAYSI) and its successor, the MAYSI-2. This study evaluated the MAYSI-2 psychometric properties based on the records of 704 youths evaluated at intake to detention facilities. In addition to factor structure, the study evaluated test-retest reliability and concurrent external validity. Results were generally encouraging in terms of the use of MAYSI-2 in detention facilities, and directions for future research are discussed.     

On the delay-dependent involvement of the hippocampus in object recognition memory

The role of the hippocampus in object recognition memory processes is unclear in the current literature. Conflicting results have been found in lesion studies of both primates and rodents. Procedural differences between studies, such as retention interval, may explain these discrepancies. In the present study, acute lidocaine administration was used to temporarily inactivate the hippocampus prior to training in the spontaneous object recognition task. Male C57BL/6J mice were administered bilateral lidocaine (4%, 0.5 microl/side) or aCSF (0.5 microl/side) directly into the CA1 region of the dorsal hippocampus 5 min prior to sample object training, and object recognition memory was tested after a short ( 5 min) or long (24 h) retention interval. There was no effect of intra-hippocampal lidocaine on the time needed for mice to accumulate sample object exploration, suggesting that inactivation of the hippocampus did not affect sample session activity or the motivation to explore objects. Lidocaine-treated mice exhibited impaired object recognition memory, measured as reduced novel object preference, after a 24 h but not a 5 min retention interval. These data support a delay-dependent role for the hippocampus in object recognition memory, an effect consistent with the results of hippocampal lesion studies conducted in rats. However, these data are also consistent with the view that the hippocampus is involved in object recognition memory regardless of retention interval, and that object recognition processes of parahippocampal structures (e.g., perirhinal cortex) are sufficient to support object recognition memory over short retention intervals.     

When does word meaning affect immediate serial recall in semantic dementia?

Patients with semantic dementia can show superior immediate recall of words that they still understand relatively well, as compared with more semantically degraded words, suggesting that conceptual knowledge makes a major contribution to phonological short-term memory. However, a number of studies have failed to show such a recall difference, challenging this view. We examined the effect of several methodological factors on the recall of known and degraded words in 4 patients with semantic dementia, in order to investigate possible reasons for this discrepancy. In general, our patients did exhibit poorer recall of the degraded words and made more phonological errors on these items. In addition, set size affected the magnitude of the recall advantage for known words. This finding suggests that semantic degradation influenced the rate of learning in the immediate recall task when the same items were presented repeatedly. The methods used to select known and degraded items also impacted on the recall difference. List length, however, did not affect the advantage for known words. The coherence of items in phonological short-term memory was affected by their semantic status, but not by the length of the material to be retained. The implications of these findings for the role of semantic and phonological representations in verbal short-term memory are discussed.     

Recognizing a plane-misoriented view of a familiar object is not influenced by the ease of specifying the main axis of elongation of that object

Participants saw three versions of pictures of familiar objects: the original unaltered (axis-normal) pictures, axis-extended pictures in which the main axes of the axis-normal pictures were elongated, and axis-switched pictures in which objects that were originally horizontally elongated were depicted as vertically elongated and vice versa. Relative to axis-normal pictures, axis extension aided decisions about whether the picture of the object was wide or tall, and axis switching hindered these decisions for both upright and plane-misoriented views. Nevertheless, although these axis manipulations clearly influenced decisions about the location of the object's main axis of elongation, axis-switched pictures were no harder to name than axis-extended pictures. Changing the depicted main axis of elongation by axis switching and axis extension did not influence object recognition in itself, whether for upright or for plane-misoriented views. This suggests that specifying the main axis of elongation of an object does not play an important role in the orientation-sensitive processes involved in identifying plane-misoriented views of that object.     

Difficulties in comprehending causal relations among children with ADHD: the role of cognitive engagement

The present study examined whether time spent in long looks (i.e., >or=15 s), an index of cognitive engagement, would account for differences between children with attention deficit hyperactivity disorder (ADHD) and comparison children in understanding causal relations. Children viewed two televised stories, once in the presence of toys and once in their absence. Dependent variables were visual attention and questions tapping factual information and causal relations. Comparison children answered significantly more causal relations questions than did the children with ADHD, but only in the toys-present condition. Four lines of evidence revealed that the difficulties children with ADHD had in answering causal relations questions in the toys-present condition could be linked specifically to this group's decreased time spent in long looks.     

Comparing learning environments in U.S. military officer education: a brief replication

A 2003 comparative study on learning environments at two military officer training sites was replicated using different methodology. Satisfaction with learning environment and with administrative inprocessing was higher at Fort Leavenworth than at Fort Dix. Most students expressed a preference for Fort Leavenworth. Satisfaction with institutional support and educational facilities appears to influence perceived satisfaction with a learning environment and with preference for training sites among senior military officers.     

Transfer of spatial behavior between different environments: implications for theories of spatial learning and for the role of the hippocampus in spatial learning

In 3 experiments, rats were required to find a submerged platform located in 1 corner of an arena that had 2 long and 2 short sides; they were then trained to find the platform in a new arena that also had 2 long and 2 short sides but a different overall shape. The platform in the new arena was easier to find if it was in a corner that was geometrically equivalent, rather than the mirror image, of the corner where it had previously been located. The final experiment revealed that hippocampal lesions impaired rats' ability to find the platform in these arenas. The results suggest that rats did not use the overall shape of the arena to locate the platform but relied on more local cues and that the hippocampus plays a role in navigation based on these cues.