Semantic clustering on common list-learning tasks: a systematic review of the state of the literature and recommendations for future directions.

INTRODUCTION: On some list-learning tasks, such as the California Verbal Learning Test (CVLT) or Hopkins Verbal Learning Test (HVLT), examinees have the opportunity to group words based on semantically related categories (i.e., semantic clustering). Semantic clustering (SC) is often considered the most efficient organizational strategy and adopting SC is presumed to improve learning and memory. In addition, SC is conceptualized as reflecting higher-order executive functioning skills. Although SC measures have intuitive appeal, to date, there are no comprehensive reviews of the SC literature base that summarize its psychometric utility. In this systematic review, we synthesize the literature to judge the validity of SC scores. METHOD: We conducted a systematic literature search for empirical articles reporting SC from the CVLT and HVLT. We qualitatively described the relationship of SC with other list-learning and cognitive test scores and clinical diagnoses, contrasting SC with serial clustering and total learning scores when possible. RESULTS: SC was inversely correlated with serial clustering. Higher SC was strongly associated with better learning and memory performances. When compared with cognitive tests, SC tended to have the strongest relationships with other memory measures and modest relationships with tests of executive functioning. SC had negligible to small relationships with most other cognitive domains. Traditional memory scores yielded stronger relationships to cognitive test performances than did SC. SC across clinical groups varied widely, but clinical groups tended to use SC less often than healthy comparison groups. CONCLUSION: Our comprehensive review of the literature revealed that SC is strongly related to measures of learning and memory on the CVLT and HVLT and is correlated with a wide range of cognitive functions. SC has been understudied in relevant populations and additional research is needed to test the degree to which it adds incremental validity beyond traditional measures of learning and memory.

Testing the consequences of alcohol, cannabis, and nicotine use on hippocampal volume: a quasi-experimental cotwin control analysis of young adult twins.

BACKGROUND: Alcohol, cannabis, and nicotine use are highly comorbid and alarmingly prevalent in young adults. The hippocampus may be particularly sensitive to substance exposure. This remains largely untested in humans and familial risk may confound exposure effects. We extend prior work on alcohol and hippocampal volume in women by testing common and unique substance use effects and the potential moderating role of sex on hippocampal volume during emerging adulthood. A quasi-experimental cotwin control (CTC) design was used to separate familial risk from exposure consequences. METHODS: In a population-based sample of 435 24-year-old same-sex twins (58% women), dimensional measures (e.g. frequency, amount) of alcohol, cannabis, and nicotine use across emerging adulthood were assessed. Hippocampal volume was assessed using MRI. RESULTS: Greater substance use was significantly associated with lower hippocampal volume for women but not men. The same pattern was observed for alcohol, cannabis, and nicotine. CTC analyses provided evidence that hippocampal effects likely reflected familial risk and the consequence of substance use in general and alcohol and nicotine in particular; cannabis effects were in the expected direction but not significant. Within-pair mediation analyses suggested that the effect of alcohol use on the hippocampus may reflect, in part, comorbid nicotine use. CONCLUSIONS: The observed hippocampal volume deviations in women likely reflected substance-related premorbid familial risk and the consequences of smoking and, to a lesser degree, drinking. Findings contribute to a growing body of work suggesting heightened risk among women toward experiencing deleterious effects of substance exposure on the still-developing young adult hippocampus.

Systematic Review of the Psychometric Properties of the Saint Louis University Mental Status (SLUMS) Examination.

OBJECTIVES: This systemic review qualitatively synthesizes existing psychometric support for the Saint Louis University Mental Status (SLUMS) Examination, a cognitive screening measure which presents as a free alternative to other widely used dementia screening measures including the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). METHODS: A total of 90 peer-reviewed articles on the SLUMS were identified from PsycINFO and PubMed databases. RESULTS: Sixty-eight records were identified and reviewed by the lead author for eligibility. Studies that included at least one psychometric property of the SLUMS (n = 20) were included in this review. CONCLUSIONS: Support for the SLUMS remains preliminary; however, it appears to have adequate validity, and adequate sensitivity and specificity in detecting cognitive impairment. Numerous shortcomings were identified, including lack of sufficient normative data, information on test-reliability, explored factor structure, and limited application of criterion measures (e.g., imaging studies, biomarkers). Research is needed to establish diverse normative samples and describe the reliability and validity of the SLUMS to strengthen the empirical support for its use. CLINICAL IMPLICATIONS: Until its psychometric properties are better established the SLUMS should be used cautiously when screening for cognitive impairment.

A co-twin-control analysis of adolescent and young adult drinking effects on learning and memory.

BACKGROUND AND AIMS: Existing evidence for a link between alcohol use and memory impairments in adolescents and young adults is largely correlational. We aimed to determine whether associations between drinking and episodic memory were consistent with a causal effect of drinking or accounted for by familial factors confounding such associations. Because cannabis use is associated with a similar pattern of performance on episodic memory measures, we assessed whether any associations might be attributable to concurrent cannabis use. DESIGN, SETTING AND PARTICIPANTS: Observational study of individuals aged approximately 20-29 years, comprising two independent population-based cohorts of twins. A co-twin-control design permitted an estimate of alcohol exposure effects free of shared genetic and environmental confounding influences. Significant associations were followed-up with twin-difference analyses. Propensity scores derived from measures collected at age 11 were used to adjust for unshared confounders. Participants in both cohorts were assessed from the age of 11 (n = 1251) under the auspices of the Minnesota Center for Twin and Family Research. MEASUREMENTS: Regression analyses with cumulative alcohol use as the predictor of interest. Multiple measures of attention, learning and memory from a widely used episodic memory task constituted dependent variables. FINDINGS: Drinking was associated with poorer attention (P ≤ 0.003) and learning (P ≤ 0.008). Results were similar across the two cohorts. The within-pair effect in twin-difference analyses was significant only for measures of learning (P-values ≤ 0.004). Results were not due to measured unshared confounders or cannabis use. Drinking in adolescence (to age 20) and early adulthood (between 20 and 29) exerted independent effects on learning. CONCLUSIONS: There appears to be a robust and specific association between drinking and learning that can be reproduced across cohorts, is not easily accounted for by confounding factors or concurrent cannabis use and is consistent with a causal influence of drinking.

Hello darkness my old friend: preferences for darkness vary by neuroticism and co-occur with negative affect.

Metaphors frequently link negative affect with darkness and associations of this type have been established in several experimental paradigms. Given the ubiquity and strength of these associations, people who prefer dark to light may be more prone to negative emotional experiences and symptoms. A five study investigation (total N = 605) couches these ideas in a new theoretical framework and then examines them. Across studies, 1 in 4 people preferred the perceptual concept of dark over the perceptual concept of light. These dark-preferring people scored higher in neuroticism (Studies 1 and 2) and experienced greater depressive feelings in daily life (Study 3). Moreover, dark preferences shared a robust relationship with depressive symptoms (Study 4) as well as generalised anxiety symptoms (Study 5). The results provide novel insights into negative affectivity and extend conceptual metaphor theory in a way that is capable of making individual difference predictions.

Maladaptive personality traits and romantic relationship satisfaction: A monozygotic co-twin control analysis.

The recent inclusion of an alternative model for personality disorders in the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-5; American Psychiatric Association, 2013a) highlights the importance of extreme variants of personality for psychopathology. The maladaptive personality traits described in the alternative model comprise 5 higher-order domains and 25 lower-order facets that capture pathological levels of personality. The present report adds to a growing body of research on the implications of maladaptive personality traits for functioning by demonstrating significant associations between each of the higher-order domains (Negative Affect, Detachment, Antagonism, Disinhibition, and Psychoticism) and most of the lower-order facets and lower romantic relationship satisfaction in a population-based sample of 284 monozygotic (MZ) adult twins. We further capitalized upon co-twin differences in levels of personality pathology in a causally informative approach, the MZ co-twin control study design. Co-twin control analyses indicated that higher levels of Negative Affect, Detachment, Disinhibition, and Psychoticism, as well as several lower-order facets, were associated with lower romantic relationship satisfaction even after accounting for the genetic and environmental factors shared by twins that confer liability toward personality pathology and psychosocial dysfunction. The present results lend support to the potentially causal implications of personality pathology for interpersonal functioning, even in a community sample unlikely to be evidencing clinical levels of pathology, by suggesting that extreme variants of personality, manifested by comparably extreme deviations in thinking, feeling, behaving, and interacting with others, may lead to impaired functioning in important domains. (PsycINFO Database Record

Linguistic Agency and Life-Span Longevity.

OBJECTIVES: Agency has been conceptualized as a drive toward mastery, control, and effective self-management. Such an agentic approach to life and its challenges may be life-prolonging, a hypothesis not previously investigated. METHOD: In four studies, individual differences in agency were assessed in terms of the frequency with which agency-related words (e.g., "achieve," "fix," and "control") were mentioned in archived interviews or speeches (N = 210). RESULTS: Higher levels of linguistic agency predicted longer life-spans among prominent physicists (study 1: n = 60, ß = .30, t = 2.30, p = .025), historians (study 2: n = 69, ß = .29, t = 2.47, p = .016), psychologists (study 3: n = 45, ß = .32, t = 2.35, p = .024), and American presidents (study 4: n = 36, ß = .75, t = 2.74, p = .010) when adjusting for birth year. Considered from another angle, life-span longevity averaged 8 years longer at a high (+1 standard deviation) relative to low (-1 standard deviation) level of the linguistic agency continuum, a marked difference. Follow-up analyses indicated that these results could not be attributed to covarying levels of positive emotion, negative emotion, or social connection, as quantified in terms of other linguistic categories. CONCLUSIONS: The investigation provides unique support for agentic perspectives on health, and several potential mechanisms are discussed.

The scope and consequences of metaphoric thinking: Using individual differences in metaphor usage to understand how metaphor functions.

People often think, feel, and behave metaphorically according to conceptual metaphor theory. There are normative sources of support for this theory, but individual differences have received scant attention. This is surprising because people are likely to differ in the frequency with which they use metaphors and, therefore, the frequency with which they experience the costs and benefits of metaphoric thinking. To investigate these ideas, a 5-study program of research (total N = 532) was conducted. Study 1 developed and validated a Metaphor Usage Measure (MUM), finding that people were fairly consistent in their tendencies toward literal thought and language on the one hand versus metaphoric thought and language on the other. These differences were, in turn, consequential. Although metaphor usage predicted susceptibility to metaphor transfer effects (Studies 2 and 3), it was also linked to higher levels of emotional understanding (Studies 4 and 5). The findings provide support for several key premises of conceptual metaphor theory in the context of a new measure that can be used to track the consequences of metaphoric thinking. (PsycINFO Database Record