Simulating individual word identification thresholds and errors in the fragmentation task

This article presents a large-scale study that collected word identification thresholds and errors in the fragmentation task for all four-letter French words. In the first part of this article, we identify some of the variables (e.g., word frequency, neighborhood size, letter confusability) that affect performance in the fragmentation task. In the second part, we analyze individual response performance and identify different response strategies. We demonstrate that the interactive activation model can account for individual response strategies by adapting two of its original parameters: word-letter feedback and letter-word inhibition. In the third part, we demonstrate that the adaptation of the interactive activation model to the fragmentation task makes it possible to successfully simulate a facilitatory frequency effect on identification thresholds, an inhibitory neighborhood size effect on error rates, and an inhibitory letter confusability effect on identification thresholds. When the task-specific processes of the fragmentation task are specified and individual response strategies are considered, the interactive activation model provides a parsimonious architecture for modeling the task-independent processes involved in word perception.     

Boys' Experimentation and Persistence in Developmental Pathways Toward Serious Delinquency

We expand on earlier work documenting developmental pathways in disruptive child behavior towards serious forms of delinquency in boys. Three pathways we hypothesized in our previous work: (a) An Authority Conflict Pathway prior to the age of 12, that starts with stubborn behavior, and has defiance as a second stage, and authority avoidance as a third stage; (b) A Covert Pathway that starts with minor convert acts, has property damage as a second stage, and moderate to serious delinquency as a third stage; and (c) An Overt Pathway that starts with minor aggression, has physical fighting as a second stage, and violence as a third stage. We now refine this work by distinguishing between boys who experiment and those who persist in disruptive behavior. Data are presented showing that the fit for the three pathways is better for persisters than for experimenters. Also, the proportion of persisters that enter each pathway at the first stage (rather than at later stages) is higher than that for experimenters. Penetration in each pathway was more common among boys who received a diagnosis of Attention-Deficit Hyperactive Disorder. Boys' rate of offending increased with penetration into pathways and with persistence on more than one pathway. Boys' persistence and advancement in the Overt or the Covert Pathway was almost invariably accompanied by their advancement in the Authority Conflict Pathway. The classification of boys according to persistence and pathways accounted for the majority of high rate offenders, according to both self-report and court adjudicated offenses.     

Taste rejection of nonnutritive sweeteners in cats.

Cats reject saccharin and cyclamate and are indifferent to dulcin, although they, like other mammals, prefer sucrose. The rejection threshold for saccharin found in this experiments, .0001 M, is about 2 log steps lower than a previously reported rejection threshold for sodium saccharin. Water produces a taste in cats adapted to their own saliva. The high sodium saccharin threshold may have resulted because the taste of the sodium saccharin was masked by the taste of the water solvent; however, saccharin may also be somewhat more aversive to the cat than sodium saccharin. Saccharin may produce an aversive taste because it stimulates receptor sites sensitive to substances bitter to man as well as those sensitive to sugars. In addition, saccharin may not be an effective stimulus for all sugar-sensitive sites.     

UNDER WHAT CIRCUMSTANCES CAN A UNIONIZED COMPANY USE TESTING FOR PROMOTION?1

A job-related, “fair test” of ability, when used as one tool and not as the sole determining factor, has been established by arbitrators to be an appropriate selection instrument. If a test has been determined as being job-related (i.e., related to the actual performance of the job), has been administered and scored both fairly and consistently, it will be considered a “fair test.” Generally, in unioncompany contracts that mention testing, a “fair test” contains the above qualifications. Arbitrators have indicated that the union involved should be afforded the opportunity to see the test; it was made quite clear, however, that the union should not have the test. In all cases reviewed, tests were upheld by arbitrators when they (1) were “fair tests,” and (2) did not conflict with the contract language. Past testing practice was not a determining factor when these two conditions existed. A total of 69 cases between 1953 and 1967 have been found relevant–27 from 1953 to 1962 and 42 from 1963 to 1967. In the first study, 13 cases were lost by a company; in six of these cases a company violated the union-company contract and in seven cases the test used did not qualify as a “fair test.” A total of twelve cases were lost by a company in the second study; in two cases a company violated the union-company contract and in ten cases the test used did not qualify as a “fair test.”     

Constraints on Pavlovian aversive conditioning: Implications for avoidance learning in the rat

Four experiments investigated the relative degree of control exerted by several conditional stimuli when each stimulus: (a) preceded shock, (b) followed shock, and preceded a shock-free interval, (c) was independent of shock, or (d) was novel. When the onset of an auditory stimulus had preceded shock (Experiments 1, 2A, and 3), it always exerted conditioned excitatory control. When the same stimulus preceded a shock-free interval, it never exerted conditioned inhibitory control. When the onset of light (Experiments 2B, 4), silence (2C), or darkness (1, 2D) preceded a shock-free interval, it always exerted conditioned inhibitory control. However, when one of the latter stimuli preceded shock, it failed to exert excitatory control. Several models of this phenomenon were tested. The implications of these results for the species-specific defence reaction and two-factor theory accounts of avoidance learning were outlined.     

Music, emotion, and autobiographical memory: They’re playing your song

Very long-term memory for popular music was investigated. Older and younger adults listened to 20-sec excerpts of popular songs drawn from across the 20th century. The subjects gave emotionality and preference ratings and tried to name the title, artist, and year of popularity for each excerpt. They also performed a cued memory test for the lyrics. The older adults' emotionality ratings were highest for songs from their youth; they remembered more about these songs, as well. However, the stimuli failed to cue many autobiographical memories of specific events. Further analyses revealed that the older adults were less likely than the younger adults to retrieve multiple attributes of a song together (i.e., title and artist) and that there was a significant positive correlation between emotion and memory, especially for the older adults. These results have implications for research on long-term memory, as well as on the relationship between emotion and memory.