Intra-basolateral amygdala infusions of AP-5 impair or enhance retention of inhibitory avoidance depending on training conditions

Previous evidence has suggested that N-methyl-D-aspartate receptors (NMDARs) in the basolateral amygdala (BLA) are critically involved in the acquisition of aversively based learning tasks. However, the role of NMDARs in the BLA in the consolidation of memory of aversive training has not been well elucidated. In the present study, the NMDAR antagonist AP-5 (1 or 3 microg) was infused into the BLA of male Sprague-Dawley rats immediately before, immediately after, or 6h after training on an inhibitory avoidance task with either a high footshock (HFS; only high dose of AP-5 given) or a low footshock (LFS; both doses of AP-5 given). The 48 h retention of animals given AP-5 (3 microg) immediately before or after HFS training was significantly impaired compared to that of vehicle-controls. In contrast, the retention of rats given AP-5 (3 microg) immediately after LFS training was significantly enhanced compared to that of vehicle-controls. AP-5 (3 microg) infusions administered 6h after training with either an HFS or LFS did not affect retention. These findings suggest that the NMDARs in the BLA are involved in both the acquisition and consolidation of aversive memory. In addition, the AP-5-induced enhancement of memory obtained with LFS training suggests that NMDARs in the BLA are involved in other mechanisms influencing synaptic transmission, in addition to their well-established role in neuroplasticity.     

A counterintuitive hypothesis about employment interview validity and some supporting evidence

This study found mixed support for the hypothesis that the difference in criterion-related validity between unstructured and structured employment interviews is due solely to the greater reliability of structured interviews. Using data from prior meta-analyses, this hypothesis was tested in 4 data sets by using standard psychometric procedures to remove the effects of measurement error in interview scores from correlations with rated job performance and training performance. In the 1st data set. support was found for this hypothesis. However, in a 2nd data set structured interviews had higher true score correlations with performance ratings, and in 2 other data sets unstructured interviews had higher true score correlations. We also found that averaging across 3 to 4 independent unstructured interviews provides the same level of validity for predicting job performance as a structured interview administered by a single interviewer. Practical and theoretical implications are discussed.     

Conditions affecting the revelation effect for autobiographical memory

In four experiments involving 184 participants, people rated their confidence that particular events had happened in their childhood (e.g., "Broke a window playing ball"). If participants had to unscramble a key word in a phrase just before rating it (e.g., "Broke a nwidwo [window] playing ball"), confidence ratings increased-the revelation effect. However, the pattern of revelation effects depended on the particular way in which participants processed key words (e.g., visualizing vs. counting vowels in the word window) approximately 10 min prior to rating life events that contained those words. Prior exposure to key words never in itself directly affected confidence ratings. These results demonstrate that one can manipulate the revelation effect by altering the processing that participants perform on words prior to unscrambling them. These results also pose difficulties for many accounts of the revelation effect. The major puzzle posed by our present findings is that unscrambling key words increases confidence that an event has happened in childhood, whereas prior exposure to these words does not.     

Resolution of conflicts between internal and external information sources on a time reproduction task: the role of perceived information reliability and attributional style

Erroneous knowledge of results (KR) that conflicts with other internal or external information sources is preferentially used and misguides performance on motor and mental timing tasks. Buekers et al. [J. Motor Behavior 26 (1994) 27] hypothesized that KR is used preferentially because participants deem it to be the most reliable information source. We tested this hypothesis in two experiments. We manipulated subjective reliability of information and information content and demonstrated that both reliability and content are assessed and used. In a third experiment we examined whether attributional style affected the use of internal and external information. While KR was present, attributional style was unrelated to performance. However, when erroneous KR was withdrawn, participants who scored high in internal attributional style or high in controllability showed more accurate performance. Whereas evaluation of information quality is explicit, information provided by the KR, whether accurate or not, may influence both implicit and explicit aspects of the tasks.     

The time course and significance of cannabis withdrawal

Withdrawal symptoms following cessation of heavy cannabis (marijuana) use have been reported, yet their time course and clinical importance have not been established. A 50-day outpatient study assessed 18 marijuana users during a 5-day smoking-as-usual phase followed by a 45-day abstinence phase. Parallel assessment of 12 ex-users was obtained. A withdrawal pattern was observed for aggression, anger, anxiety, decreased appetite, decreased body weight, irritability, restlessness, shakiness, sleep problems, and stomach pain. Onset typically occurred between Days 1-3, peak effects between Days 2-6, and most effects lasted 4-14 days. The magnitude and time course of these effects appeared comparable to tobacco and other withdrawal syndromes. These effects likely contribute to the development of dependence and difficulty stopping use. Criteria for cannabis withdrawal are proposed.     

Effects of the terrorist attacks of 9/11/01 on employee attitudes

Much has been stated in the popular press about the effects of the events of 9/11/01 on employee attitudes about work. This study examined a large sample (N = 70,671) of employees of a multinational manufacturer whose annual employee survey data collection was interrupted by the events. After demonstrating measurement equivalence across time and countries, changes in attitudes pre- and post-9/11 were examined. Only negligible differences were found in Job Satisfaction, Supervisor Evaluation, Stress, and Organizational Commitment to Diversity for U.S. employees or for employees worldwide. Demographic differences in response to events were not found. Implications for understanding effects of stressful external events on employee perceptions of work are discussed.     

Predicting stuttering from linguistic factors for German speakers in two age groups

Brown's factors [J. Speech Disorders 10 (1945) 181] predict the likely loci of disfluency in English-speaking adults who stutter. A word is more likely to be stuttered for these speakers if it is a content word, starts with a consonant, is positioned at the beginning of a sentence, and if it is a long word. These same factors were examined in native German-speaking children and adults who stutter. Speech data of 15 German adults and 17 children were coded according to Brown's factors. For the adult group, it was predicted that words starting with consonants would not lead to as much of an increase in disfluencies compared with English samples, because of cross-linguistic differences in syllable onset properties. It was predicted that stuttering would be more likely in later sentence positions in German because in German the verb is usually near the end of a sentence. There were no obvious reasons to expect differences on the two remaining factors, content words and word length. With children, it was hypothesised that Brown's factors that specify level of linguistic difficulty would not be such a good predictor of stuttering rate. Specifically, it was predicted that the difference in stuttering rate between function and content words would be lower in children. For the adults both word type (content/function) and word length increased stuttering rate significantly, whereas changes in stuttering rate for the other two factors were non-significant. It was also found that when word difficulty (based on a combined measure of all factors) increased, stuttering rate rose. With children, only the word-length factor was significant, and stuttering rate was not governed to the same extent by overall word difficulty. Conclusions are drawn as to the effect of linguistic and motor influences on stuttering. EDUCATIONAL OBJECTIVES: The reader will learn about and be able to describe: (1) how linguistic factors affect stuttering rates in German; (2) the different patterns of adults and children who stutter and how language might influence this pattern; and (3) how to interpret these findings in light of a current theory of fluency failure.     

Assumed policy similarity and voter preference

The effects of attitude similarity on voters' preferences were examined. Using secondary analyses, the authors created measures of assumed similarity across 6 issues between voters and U.S. presidential candidates (in 1972). Greater similarity was associated with greater attraction (operationalized in terms of voters' presidential preferences). In 2 independent analyses, perceived similarity resulted in predictive accuracy of 84% to 88%. In a 3rd analysis, the predictive efficiency of each of 6 similarity measures was determined and used to develop a model that accurately predicted voters' actions in a hold-out sample. Findings demonstrate the importance of perceived attitude similarity in determining voter preferences and suggest the utility of earlier similarity-attraction research for the development of models of policy choice behavior.     

"Seeing things in my head": a synesthete's images for music and notes

We explored synesthetic experiences (photisms) elicited by music and notes for GS, a 22-year-old female college student, who is a genuine digit synesthete (Mills et al 1999 Cognitive Neuropsychology 16 181-191). After extensive interviews, we conducted five studies using synthesizer notes in different octaves and in different instrument sounds. GS described, drew, or selected her photisms from alternatives. The results were: (a) her photisms had shape, color, movement, and texture: (b) different instruments had photisms with different shapes and families of instruments had similar shapes; (c) low-pitched notes were darker and larger than high notes; (d) instrument and pitch affected each other; (e) a given note was perceived as darker after a high note than after a low note; and (f) GS's drawings of notes became more consistent with repeated trials. Theoretical observations are discussed on the basis of these results.