Luria-nebraska neuropsychological battery: High rates of false positives for geriatirc subjects

This study examined false positive rates obtained for two normal adult age groups, using three different methods for interpreting performances on the Luria-Nebraska Neuropsychological Battery (LNNB). Among normal subjects ages 18 to 30 and ages 65 to 85, false positive rates were found to range from 3.9% to 7.7% for younger subjects and 13.5% to 32.7% for older subjects. Significant differences were found between the proportion of false positives in each age group on each method of interpretation. A lack of agreement was found between the three different methods of interpretation concerningwhich subjects should be classified as impaired. Further analysis was performed by dividing older subjects into two groups, ages 65 to 70 and over 70. False positive rates for subjects over age 70 were found to range from 20.7% to 41.4%. Significant differences were also found between the proportion of false positives in each of these two groups.     

An economic model of scientific activity and truth acquisition

We wish to thank the following for helpful comments and discussion: Jim Cox, Hartry Field, David Hull, Mark Isaac, Isaac Levi, Vann McGee, Mike Phillips, Holly Smith, Meredith Williams, Michael Williams, and other audience members at Northwestern University and Western Washington University.     

An effect of linguistic experience: The discrimination of [r] and [l] by native speakers of Japanese and English

To test the effect of linguistic experience on the perception of a cue that is known to be effective in distinguishing between [r] and [l] in English, 21 Japanese and 39 American adults were tested on discrimination of a set of synthetic speech-like stimuli. The 13 “speech” stimuli in this set varied in the initial stationary frequency of the third formant (F3) and its subsequent transition into the vowel over a range sufficient to produce the perception of [r a] and [l a] for American subjects and to produce [r a] (which is not in phonemic contrast to [l a ]) for Japanese subjects. Discrimination tests of a comparable set of stimuli consisting of the isolated F3 components provided a “nonspeech” control. For Americans, the discrimination of the speech stimuli was nearly categorical, i.e., comparison pairs which were identified as different phonemes were discriminated with high accuracy, while pairs which were identified as the same phoneme were discriminated relatively poorly. In comparison, discrimination of speech stimuli by Japanese subjects was only slightly better than chance for all comparison pairs. Performance on nonspeech stimuli, however, was virtually identical for Japanese and American subjects; both groups showed highly accurate discrimination of all comparison pairs. These results suggest that the effect of linguistic experience is specific to perception in the “speech mode.”     

Bargaining ability,the utility of playing a game,and models of coalition formation

A utility function for playing a given position in a game is developed as a natural extension of the utility function which defines the rewards available in the game. This function is determined by a player's opinion of his bargaining ability. A characterization of such utilities is obtained which generalizes previous results that the Shapley value and Banzhaf-Coleman index are both cardinal utility functions which reflect different bargaining abilities. The approach taken here is related to models of coalition formation.     

Visual recognition memory for complex configurations

Previous studies of recognition memory for heterogeneous pictorial stimuli suggest an unusually large storage and retrieval capacity. In the first experiment, three series of homogeneous pictures (faces, ink blots, snow crystals) were presented to six independent groups of Ss, and recognition was tested immediately or 48 h later. Accuracy and sex were related to stimulus configuration; at both time intervals, accuracy was best for faces and poorest for snow crystals. Levels of accuracy were below those attained in studies using heterogeneous arrays. The results of two other experiments suggest the relative unimportance of verbal mediation in recognition of homogeneous pictorial stimuli.     

Perceptual equivalence of two acoustic cues for stop-consonant manner

The first experiment examined the effects of orthogonal variation in two acoustic cues that are both produced by the articulation of a stop consonant. One component of the articulation produces a temporal cue, the other a spectral cue. In a phonetic identification task, these quite different cues were found to engage in a trading relation: One cue could, within limits, substitute for the other. In a second experiment, the perceptual equivalence implied by that trading relation was put to a stricter test. If the cues are truly equivalent in perception, then they should have their effects on the same perceptual dimension. That being so, it should be possible to combine them in such a way that, working at cross purposes in the perceptual domain, they effectively cancel each other. Pairs of patterns so produced should, then, be harder to discriminate than pairs produced by either cue alone, and still harder than those produced when the (same) two cues are combined in the opposite way and so cooperate. That expectation was confirmed. We suggest that the equivalence thus demonstrated comes about because the two cues are processed by a system specialized to take account of their common origin in speech production. So interpreted, the equivalence may be viewed as an instance of distinctively phonetic perception.     

What is Psychotherapy for? A Plausible Alternative to Empirically Supported Therapies,Therapy Relationships,and Practice Guidelines

Task forces come up with empirically supported therapies and therapist-client relationships. A careful study of their research provides an empirically supported answer to the long-standing question of what psychotherapy is for. Accordingly, if your way of doing therapy falls outside the empirically based boundary, (a) you can risk declining their practice guidelines; (b) you can develop your own practice guidelines; and (c) you can pursue some exciting implications from having an alternative set of guidelines for how to do psychotherapy. A strategy is proposed as a plausible alternative to the task forces empirically based strategy.