The effects of pre- and postweaning rearing conditions on latent inhibition and partial reinforcement extinction effect in male rats

Male rats were either handled daily or left undisturbed (nonhandled) during the first 21 days of life. At weaning (Day 22) animals in each early treatment condition were assigned to two housing conditions, isolated or grouped, creating four early/late treatment conditions: Handled-Grouped (HG), Handled-Isolated (HI), Nonhandled-Grouped (NHG), and Nonhandled-Isolated (NHI). At maturity, all animals were tested in the latent inhibition (LI, Experiment 1) and the partial reinforcement extinction effect (PREE, Experiment 2) paradigms. In LI, animals receiving prior nonreinforced preexposure to a stimulus (PE) show subsequently retarded conditioning to that stimulus as compared to nonpreexposed (NPE) controls. In the PREE, partially reinforced (PRF) animals exhibit higher resistance to extinction as compared to continuously reinforced (CRF) controls. LI and PREE were obtained in the HG condition, but were impaired in NHG and HI animals. The pattern of impairment was different in the two conditions. The absence of LI in NHG males was due to increased suppression in the PE group, whereas in HI males, was due to decreased suppression in the NPE group. Likewise, the attenuation of the PREE in NHG males stemmed primarily from decreased resistance to extinction in the PRF group, whereas in HI males, it resulted from increased resistance to extinction in the CRF group. The combination of nonhandling and isolation led to the reinstatement of both LI and PREE: normal LI and PREE were obtained in the NHI animals. These results demonstrate that early rearing experience interacts with later experience differentially depending upon the later experience.     

Separating sensitivity from response bias: implications of comparisons of yes-no and forced-choice tests for models and measures of recognition memory

A fundamental challenge to psychological research is the measurement of cognitive processes uncontaminated by response strategies resulting from different testing procedures. Test-free estimates of ability are vital when comparing the performance of different groups or different conditions. The current study applied several sets of measurement models to both forced-choice and yes-no recognition memory tests and concluded that the traditional signal-detection model resulted in distorted estimates of accuracy. Two-factor models were necessary to separate memory sensitivity from response bias. These models indicated that (a) memory accuracy did not differ across the tests and (b) the tests relied on the same underlying memory processes. The results illustrate the pitfalls of using a single-component model to measure accuracy in tasks that reflect 2 or more underlying processes.     

Recognition memory for source and occurrence: The importance of recollection

Previous recognition memory studies indicate that when both recollection and familiarity are expected to contribute to recognition performance (e.g., discriminating studied items from nonstudied items) the dual-process and the unequal-variance signal detection models provide comparable accounts of performance. When familiarity is not expected to be useful (e.g., when items from two equally familiar sources are discriminated between), the dual-process model provides a significantly better account of performance. In the present study, source recognition was tested under conditions in which familiarity could have been used to perform a list-discrimination task; participants were required to discriminate between strong studied items, weak studied items, and new items. The dual-process model provided a better account of performance than did the unequal-variance model. Moreover, the results indicated that the unequal-variance assumption in a single-process signal detection model was not a valid substitution for recollection and that recollection was used to make recognition judgments even when assessments of familiarity were useful.     

A conceptual model of cultural predictors of anxiety among Japanese American and part-Japanese American adolescents

A model integrating Japanese ethnicity, cultural identity, and anxiety was developed and assessed in Japanese American and part-Japanese American high school seniors (N = 141). Using measures from the Hawaiian High Schools Health Survey, the model incorporated the State-Trait Anxiety Inventory, the Major Life Events Scale, and the Japanese Culture Scale (JCS). Japanese American adolescents scored higher on the JCS and reported fewer anxiety symptoms than part-Japanese American adolescents. Predictors for anxiety were being Japanese American versus part-Japanese American, income, and culturally intensified events. A significant interaction of behavior by self-identification was obtained. The model had good overall fit, suggesting that cultural identity formation may contribute to anxiety experienced particularly by adolescents of mixed heritage.     

Linear versus Hierarchical Agreement Feature Processing in Comprehension

Two experiments examined whether syntactic number features are tracked during comprehension with a linear slot-based memory system or with a hierarchical feature-passing system. In a construction such as The pond near the trail(s) for the horse(s) was ¨, a linear account of subject-number tracking predicts greater interference from horses (N3), whereas a hierarchical account predicts greater interference from trails (N2). Experiment 1 used singular-head subject noun phrases (e.g., pond) and showed equal interference from N2 and N3, failing to differentiate between linear and hierarchical accounts. Experiment 2 used plural-head subjects and revealed more interference from N2 than N3. The pattern across the experiments accords with the ideas that (1) feature-tracking is hierarchical (e.g., Vigliocco & Nicol, 1997), (2) plurals are marked (e.g., Eberhard, 1997), and (3) subject-number information decays across intervening number-marked elements.     

Predicting individual false alarm rates and signal detection theory: A role for remembering

The relationships between hit, remember, and false alarm rates were examined across individual subjects in three remember-know experiments in order to determine whether signal detection theory would be consistent with the observed data. The experimental data differed from signal detection predictions in two critical ways. First, remember reports were unrelated, or slightly negatively related, to the commission of false alarms. Second, both response types (remembers and false alarms) were uniquely related to hit rates, which demonstrated that the hit rate cannot be viewed as the result of a single underlying strength process. These results are consistent with the dual-process signal detection model of Yonelinas (1994), in which performance is determined by two independent processes--retrieval of categorical context information (remembering) and discriminations based on continuous item strength. Remember and false alarm rates selectively tap these processes, whereas the hit rate is jointly determined. Monte Carlo simulations in which the dual-process model was used successfully reproduced the pattern in the experimental data, whereas simulations in which a signal detection model, with separate "old" and "remember" criteria, was used, did not. The results demonstrate the utility of examining individual differences in response types when one is evaluating memory models.     

A multilevel analysis of effort, practice, and performance: effects; of ability, conscientiousness, and goal orientation

This article examines the relationship between motivation and performance during skill acquisition. The authors used multilevel analysis to investigate relationships at within- and between-person levels of analysis. Participants were given multiple trials of practice on an air traffic control task. Measures of effort intensity and performance were taken at repeated intervals. As expected, the relationship between effort and performance increased with practice. Furthermore, the rate at which this effect strengthened was faster for individuals with high-ability or low-performance orientation. There was also an interaction between learning and performance orientations that only emerged after practice. By the end of practice, the negative effects of performance orientation were stronger for individuals with high learning orientation. Results highlight the importance of adopting a multilevel framework to enhance understanding of the link between motivation and performance.