Quantifying the Interplay of Semantics and Phonology During Failures of Word Retrieval by People With Aphasia Using a Multiplex Lexical Network

Investigating instances where lexical selection fails can lead to deeper insights into the cognitive machinery and architecture supporting successful word retrieval and speech production. In this paper, we used a multiplex lexical network approach that combines semantic and phonological similarities among words to model the structure of the mental lexicon. Network measures at different levels of analysis (degree, network distance, and closeness centrality) were used to investigate the influence of network structure on picture naming accuracy and errors by people with Anomic, Broca's, Conduction, and Wernicke's aphasia. Our results reveal that word retrieval is influenced by the multiplex lexical network structure in at least two ways—(a) the accuracy of production and error type on incorrect productions were influenced by the degree and closeness centrality of the target word, and (b) error type also varied in terms of network distance between the target word and produced error word. Taken together, the analyses demonstrate that network science techniques, particularly the use of the multiplex lexical network to simultaneously represent semantic and phonological relationships among words, reveal how the structure of the mental lexicon influences language processes beyond traditionally examined psycholinguistic variables. We propose a framework for how the multiplex lexical network approach allows for understanding the influence of mental lexicon structure on word retrieval processes, with an eye toward a better understanding of the nature of clinical impairments, like aphasia.     

Strategies for learning proper names: expanding retrieval practice,meaning and imagery

Name learning strategies including retrieval practice, semantic associations and imagery were compared in laboratory‐based and real‐life experiments. Experiments 1 and 2 studied expanding retrieval practice and a semantic association strategy as memory improvement techniques for learning proper names. Participants either retrieved or restudied names on the same, expanding schedule. After a short, filled interval, cued recall of names was about 250% better following retrieval than restudy and 200% better with than without semantic associations. Together, the techniques improved recall by 300–400%. In Experiment 3, retrieval practice was compared with an imagery mnemonic for name learning under real‐life social conditions: Participants sought to learn the names of people they met at a party. Retrieval practice produced 50% higher recall after 24–72 hours but the imagery mnemonic was no more effective than non‐directed instructions to learn names. Copyright © 2005 John Wiley & Sons, Ltd.     

Using latent trait modeling to conceptualize an alcohol problems continuum

Recent research points toward the viability of conceptualizing alcohol problems as arrayed along a continuum. Nevertheless, modern statistical techniques designed to scale multiple problems along a continuum (latent trait modeling; LTM) have rarely been applied to alcohol problems. This study applies LTM methods to data on 110 problems reported during in-person interviews of 1,348 middle-aged men (mean age=43) from the general population. The results revealed a continuum of severity linking the 110 problems, ranging from heavy and abusive drinking, through tolerance and withdrawal, to serious complications of alcoholism. These results indicate that alcohol problems can be arrayed along a dimension of severity and emphasize the relevance of LTM to informing the conceptualization and assessment of alcohol problems.     

Spatial information processing consequences of DAMGO injections into the dorsal striatum

The purpose of the present study was to examine the role of the dorsal striatum, and more specifically, the patch region of the dorsal striatum, in mediating spatial learning and memory. To this end, male, Long Evans rats were bilaterally implanted with cannula aimed at the dorsal striatum. Rats were injected with different doses (0, 0.05, 0.5 or 5 microg/0.5 microl) of [3H]-[D-Ala2,MePhe4,Gly-ol5]-enkephalin (DAMGO) into the dorsal striatum daily (Exp. 1) before training on a hidden platform version of the water maze task or during a reversal water maze spatial task (Exp. 2). In both experiments, probe retention tests were given drug free. Results from Exp. 1 showed that intra-striatal injection of the low DAMGO dose (0.05) resulted in enhanced spatial acquisition while the high dose (5.0) produced impairments compared to controls. During the probe test, the low dose group showed better retention of the platform location than controls as well as an enhanced ability to alter their search strategy. In Exp. 2, pretraining alleviated the high dose impairment found in Exp. 1 suggesting a motoric impairment in this group. The low dose group continued to show an enhanced ability to alter their search strategy during the probe test compared to all other groups. The data suggest that the low dose of DAMGO, when injected into the dorsal striatum, eliminates competition with the hippocampus thereby leading to enhanced spatial processing. Alternatively, inhibition of patch-striatal neurons may attenuate a memory decay process. Both alternatives are discussed.     

BUDDHISM AND PSYCHOANALYSIS: A PERSONAL REFLECTION

Around 600 BC Siddhartha Gotama practiced intensive meditation for several years and found a way for people to cultivate a sense of equanimity, wisdom, and compassion in their lives. Around 1900 AD Sigmund Freud undertook several years of intensive self-analysis and developed theories and therapeutic techniques for understanding how the unconscious operates in our lives to perpetuate neurotic suffering, and how we might gain insight and relief from that suffering and be more free to move toward our potential in this life. This article gives an overview of Buddhist theory and practice, gives an account of the author’s personal journey through both disciplines, and then point outs the similarities and differences in them, leading to an integration of elements of these two paths of exploration of the psyche, for the purpose of mutual enrichment.Dr. Nichol is a graduate of the Menninger Clinic and the Houston-Galveston Psychoanalytic Institute, and he is in private practice.     

A bifactor approach to modeling the structure of the psychopathy checklist-revised

To date, models of the structure of psychopathy as assessed by the Psychopathy Checklist-Revised (PCL-R) have taken a higher-order approach in which the factors of the PCL-R are modeled as correlated elements of a higher-order psychopathy construct. Here, we propose an alternative structural model of the PCL-R, the bifactor model, which accounts for the covariance among PCL-R items in terms of a general factor reflecting the overlap across all items, and independent subfactors reflecting the unique coherency among particular groups of items. We present examples of how this alternative structural model can account for diverging associations between different subsets of PCL-R items and external criteria in the domains of personality and psychopathology, and we discuss implications of the bifactor model for future research on the conceptualization and assessment of psychopathy.     

Generalization of self-instruction training

Forty-eight preoperational and concrete operational first and second graders performed on a training task (Matching Familiar Figures Test) and a generalization task (a perceptual perspective taking task) prior to, and after serving in, one of two instructional groups. The instructional groups were: a no-training control group and a group which received general content self-instructions delivered through a directed discovery procedure. Both preoperational and concrete operational children in the self-instruction group improved significantly at posttest on the training task. On the generalization task only the concrete operational children in the directed discovery group performed significantly better following training. These findings are discussed in terms of the dynamic relationship between an individual's cognitive ability and the format of instructions. The need for provoking the cognitive involvement of the child on the basis of this relationship is stressed.