Beyond mind-reading: multi-voxel pattern analysis of fMRI data

A key challenge for cognitive neuroscience is determining how mental representations map onto patterns of neural activity. Recently, researchers have started to address this question by applying sophisticated pattern-classification algorithms to distributed (multi-voxel) patterns of functional MRI data, with the goal of decoding the information that is represented in the subject's brain at a particular point in time. This multi-voxel pattern analysis (MVPA) approach has led to several impressive feats of mind reading. More importantly, MVPA methods constitute a useful new tool for advancing our understanding of neural information processing. We review how researchers are using MVPA methods to characterize neural coding and information processing in domains ranging from visual perception to memory search.     

Sex and personality traits influence the difference between time taken to tell the truth or lie

A necessary component of lying is the withholding of a truthful response. Hence, lying may be conceptualised as involving the inhibition of an initial, automatic response (the truth) while an alternative response (the lie) is generated. We investigated response times to visually and auditorially presented questions probing recent episodic memory, when subjects answered questions truthfully or with lies. We also investigated whether the absolute response times or difference between time taken to tell the truth or lie was affected by participants' sex or correlated with personality scores on the Eysenck Personality Questionnaire Revised-Short Scale. 61 subjects answered the same 36 questions five times. The first time involved answering all questions truthfully, which allowed post hoc analysis of whether subjects had been consistent in their lying and truth-telling on the following four occasions. These latter four occasions involved answering all questions (one each with 'truth' or 'lie') for both types of presentation. Regardless of type of presentation or subjects' sex, subjects took approximately 200 msec. longer to lie than to tell the truth in response to each question (p<.001). There were significant correlations between truthful response times to auditorially presented questions and Eysenck 'Neuroticism' scores. There was also a significant correlation for women between mean individual lie-minus-truth time to auditorially presented questions and Eysenck 'Lie' scores. These preliminary data suggest that response time is systematically longer when telling a lie and that personality variables may play a part in this process.     

Assessing Organizational Behavior Models: A Comparison of Linear and Nonlinear Methods1

This study highlights the use of nonlinear statistic techniques in a behavioral model that incorporates dispositional and situational variables. When ordinary least squares and log-linear/logit results were compared, various unique associations were found between job satisfaction, job complexity, locus of control, and the number of available benefits. Overall, the findings prove that more nonlinear modeling is needed in the behavioral sciences.     

FURTHER ANALYSIS OF PROBLEM BEHAVIOR IN RESPONSE CLASS HIERARCHIES

A functional analysis identified the reinforcers for 3 participants' problem behavior, but only relatively mild problem behaviors (e.g., screaming, disruption) were observed when all topographies produced tested consequences. We then conducted an extinction analysis in which specific topographies produced a reinforcer while all other topographies were on extinction. The extinction analysis confirmed that the same reinforcer identified in the initial functional analysis maintained more severe topographies of problem behavior (e.g., aggression). In addition, results of the extinction analysis indicated that 2 of the participants displayed patterns of responding consistent with a response class hierarchy hypothesis, in which less severe problem behavior frequently occurred prior to more severe topographies. The 3rd participant displayed a response pattern indicative of differential reinforcement effects.     

Language laterality in Navajo reservation children: dichotic test results depend on the language context of the testing

Language lateralization in 40 Navajo and 20 Anglo fifth graders was assessed via the Dichotic Consonant-Vowel Task (DCVT). One group of Navajo children was tested by an experimenter who spoke only Navajo with them. The other Navajo group and the Anglo group were tested by an experimenter who spoke only English to them. Strong right ear advantages (REAs) were obtained for the Anglo group and for the Navajo group tested by the Navajo-speaking experimenter. The Navajo group tested by the English-speaking experimenter showed minimal, nonsignificant REAs. Previous findings of an absence of REAs in Native American children failed to consider the possibility that this might occur only when the experimenter does not speak the dominant language of the children. Our results are not consistent with the view that Native Americans are more right hemisphere dominant as a function of an "appositional" mode of language and thought.     

Predicting Generative Concern in Young Adulthood from Narrative Intimacy: A 5-Year Follow-Up

According to Erikson’s developmental model, achieving intimacy in young adulthood should predict higher levels of generativity later in life. This mixed quantitative and qualitative, longitudinal study examined the relationship between generative concern and intimacy in young adulthood (from ages 26–32). Participants (N = 147; 69 % female; 74.1 % college educated) told a narrative about a “relationship defining moment” with a same-sex friend, and completed self-report questionnaires of optimism and generative concern at ages 26 and 32. Optimism and generative concern had strong stability over time, while friendship intimacy did not exhibit test–retest stability. Most participants (88.6 %) disclosed a different story at each time point, which contributed to the lack of rank-order stability for friendship intimacy in the present study. Friendship intimacy was positively correlated with age 26 and age 32 generative concern. Both sex and optimism predicted longitudinal increases in generative concern over 5 years, with women and people higher in optimism seeing larger increases. Friendship intimacy coded from narratives at 26 predicted (p = .052) increases in generative concern at 32. The present study extended prior research by examining the relationship between intimacy and generative concern as people develop from emerging to young adulthood. Following Erikson, developing close relationships with others, exhibiting an optimistic outlook on life, and being female appear to facilitate greater generative concern in young adults.