Rats’ novel object interaction as a measure of environmental familiarity

Environmental familiarization is a learning phenomenon embedded within most tasks used to study learning and motivation. Given its prevalence there is surprisingly little systematic behavioral research on factors affecting familiarization. The six experiments reported in the present report used rats’ tendency to interact more with a novel object in a familiar than in a novel environment as a measure of environmental familiarization. We found that 3 min of exposure to the environment was sufficient to increase object interaction above unfamiliar controls even when testing occurred up to 48 h after initial exposure to the environment; 1 or 1.5 min of exposure was not sufficient. Also, in the brief 2 min test, 10 min of environment exposure did not appear to increase object interaction above the 3-min condition. The 3-min of environment exposure was sufficient for familiarization whether environment exposure occurred in one 3 min placement or two 1.5 min placements. Environmental familiarization as measured by object interaction was also sensitive to ‘interference’ manipulations. That is, a distinct object present during initial exposure to the environment produced a level of object interaction in testing comparable to an unfamiliar control. Similarly, exposure to a second distinct alternate environment immediately after, but not before, initial exposure to the test environment partially disrupted environmental familiarization. In sum, object interaction might serve as a useful measure for studying processes mediating environmental familiarity.     

Organizational socialization tactics and newcomer proactive behaviors: An integrative study

The purpose of this study was to examine the relationship between organizational socialization tactics, newcomers’ self-efficacy, proactive behaviors, and socialization outcomes. Based on a sample of 140 co-op university students who completed surveys at the end of their work term, the results indicated that newcomers’ self-efficacy and institutionalized socialization tactics were positively related to newcomer proactive behaviors. The results also indicated that newcomer proactive behaviors partially mediated the relationship between their self-efficacy and organizational socialization tactics with a number of proximal and distal socialization outcomes. Furthermore, feedback-seeking and information-seeking moderated the relationship between socialization tactics and several socialization outcomes. Institutionalized socialization tactics were more strongly related to socialization outcomes for newcomers who engaged in less feedback-seeking and information-seeking behavior. These results support an interactionist approach to organizational socialization in which newcomers’ self-efficacy, proactive behavior, and organizational socialization tactics all contribute to newcomers’ adjustment and socialization.     

Relating different perspectives on how outcomes of behavior influence behavior

Many researchers have tackled the question of how behavior is influenced by its outcomes. Some have adopted a nonmechanistic (functional) perspective that attempts to describe the influence of outcomes on behavior. Others have adopted a mechanistic (cognitive) perspective that attempts to explain the influence of outcomes on behavior. Orthogonal to this distinction, some have focused on the influence of outcomes that a behavior had in the past, whereas others also consider the influence of outcomes that a behavior might have in the future. In this article, we relate these different perspectives with the goal of reducing misunderstandings and fostering collaborations between researchers who adopt different perspectives on the common question of how behavior is influenced by its outcomes.     

A latent class analysis of positive psychosis symptoms based on the British Psychiatric Morbidity Survey

This study aimed to describe the distribution of positive psychosis symptoms in a large scale, population-based sample. Data from the British Psychiatric Morbidity Survey was used to examine homogeneous sub-types of participants based on their responses to the five probe items of the Psychosis Screening Questionnaire. Latent class analysis was used to identify the underlying class structure of psychosis. Four classes of psychosis were identified. Associations between the latent classes and the demographic risk factors, clinical variables and reports of traumatic experiences showed significantly higher risks for the psychosis class, the paranoid class, and the intermediate class compared to the normative class. Four classes that appeared to represent an underlying continuum could best explain psychosis symptom expression at the population level.     

Formal distinctiveness of high- and low-imageability nouns: analyses and theoretical implications

Words associated with perceptually salient, highly imageable concepts are learned earlier in life, more accurately recalled, and more rapidly named than abstract words (R. W. Brown, 1976; Walker & Hulme, 1999). Theories accounting for this concreteness effect have focused exclusively on semantic properties of word referents. A novel possibility is that word structure may also contribute to the effect. We report a corpus-based analysis of the phonological and morphological structures of a large set of nouns with imageability ratings (N = 2,023). High- and low-imageability nouns differed by length, etymology, prosody, affixation, phonological neighborhood density, and rates of consonant clustering. On average, nouns denoting abstract concepts were longer, more derivationally complex, and emerged in English from a different distribution of languages than did concrete nouns. We address implications for interactivity of word form and meaning as pertain to theories of word concreteness, lexical acquisition, and word processing.     

Positive aspects of caregiving as a moderator of treatment outcome over 12 months

The authors examined the influence of positive aspects of caregiving (PAC) as a moderator of treatment outcome across 12 months in 1 of the original sites of the Resources for Enhancing Alzheimer's Caregiver Health I project. They used multilevel random coefficients regression analysis to predict time-varying PAC, depression, behavioral bother, and daily care burden in Alzheimer's caregivers (N = 243; mean age = 60.89, SD = 14.19). They found that time-varying PAC was predicted by time-varying daily care burden. They also found significant effects of time-varying PAC for depression, behavioral bother, and daily care burden. Notably, a PAC x Phase x Treatment effect was found for daily care burden, such that individuals who endorsed less PAC benefited most from the intervention across 12 months. The tendency to positively appraise the caregiving experience (i.e., PAC) in response to chronic stressors such as Alzheimer's caregiving may affect individuals' responsiveness to, and benefit from, interventions, whereas only daily care burden affected the tendency to find enjoyment in caregiving across 12 months. Future intervention research should assess individual PAC in order to better tailor interventions to caregiving needs.     

Neuroanatomical correlates of handedness for tool use in chimpanzees (Pan troglodytes): implication for theories on the evolution of language

It has been hypothesized that cognitive mechanisms underlying lateralized complex motor actions associated with tool use in chimpanzees may have set the stage for the evolution of left-hemisphere specialization for language and speech in humans. Here we report evidence that asymmetries in the homologues to Broca's and Wernicke's areas are associated with handedness for tool use in chimpanzees. These results suggest that the neural substrates of tool use may have served as a preadaptation for the evolution of language and speech in modern humans.     

Hands-free versus hand-held cell phone conversation on a braking response by young drivers

As some states allow motorists to use hands-free cell phones only while driving, this study was done to examine some braking responses to see if conversing on these two types of cell phones affects quick responding. College-age drivers (n=25) completed reaction time trials in go/no-go situations under three conditions: control (no cell phone or conversation), and conversing on hands-free and hand-held cell phones. Their task involved moving the right foot from one pedal to another as quickly as possible in response to a visual signal in a lab setting. Significantly slower reaction times, movement times, and total response times were found for both cell phone conditions than for the control but no differences between hands-free and hand-held phone conditions. These findings provide additional support that talking on cell phones, regardless if it is hands-free or hand-held, reduces speed of information processing.     

Reactive and proactive control in incarcerated and community adolescents and young adults

This study compared the cognitive control skills of male incarcerated adolescents (n = 44), male control adolescents (n = 33), male incarcerated young adults (n = 41), and male control young adults (n = 35) using the AX-continuous performance test (AX-CPT). This test measures proactive control (the ability to maintain a mental representation of goal-related information in preparation for a behavioral response) and reactive control (the ability to activate goal-related information in response to an external trigger). Incarcerated individuals had more difficulty implementing proactive control, whereas control individuals had more difficulty implementing reactive control. Adolescents had more difficulty with both reactive and proactive control compared with young adults, suggesting that both skills improve with age. Additional analyses indicated that the effect of age on proactive control was due to the presence of attention-deficit/hyperactivity disorder, whereas the effect of age on reactive control appeared to be a natural developmental trend that could not be explained by other variables. These findings are considered in relation to the dual mechanisms of control theory [Braver, T. S., Gray, J. R., & Burgess, G. C. (2007). Explaining the many varieties of working memory variation: Dual mechanisms of cognitive control. In A. R. A. Conway, C. Jarrold, M. J. Kane, A. Miyake, & J. N. Towse (Eds.), Variation in Working Memory. New York: Oxford University Press.].     

Mindfulness Meditation for Symptom Reduction in Fibromyalgia: Psychophysiological Correlates

Objectives Fibromyalgia, a chronic pain syndrome, is often accompanied by psychological distress and increased basal sympathetic tone. In a previous report it was shown that mindfulness-based stress-reduction (MBSR) reduced depressive symptoms in patients with fibromyalgia with gains maintained at two months follow-up (Sephton et al., Arthr Rheum 57:77–85, 2007). This second study explores the effects of MBSR on basal sympathetic (SNS) activation among women with fibromyalgia. Methods Participants (n = 24) responded to a television news appearance, newspaper, and radio advertisements. Effects on anxiety, depressive symptoms, and SNS activation measures were tested before and after MBSR using a within-subjects design. Results The MBSR treatment significantly reduced basal electrodermal (skin conductance level; SCL) activity (t = 3.298, p = .005) and SCL activity during meditation (t = 4.389, p = .001), consistent with reduced SNS activation. Conclusions In this small sample, basal SNS activity was reduced following MBSR treatment. Future studies should assess how MBSR may help reduce negative psychological symptoms and attenuate SNS activation in fibromyalgia. Further clarification of psychological and physiological responses associated with fibromyalgia may lead to more beneficial treatment.