Personality Correlates of Self-Injury in Adolescent Girls: Disentangling the Effects of Lifetime Psychopathology

Adolescent non-suicidal self-injury (aNSSI) is associated with abnormal scores on personality traits, such as high neuroticism. However, no studies to date have examined personality facets of self-injury in a cohort younger than college-age. Plus, adolescent psychopathologies, especially Depressive Disorders, are associated with a similar personality profile and are highly comorbid with aNSSI. Consequently, it remains unclear whether personality provides insights about aNSSI in youth beyond that due to underlying psychopathology. 550 community-dwelling 13- to 15-year-old never-depressed adolescent girls were interviewed for lifetime aNSSI and lifetime psychopathology. Personality traits, broad domains and specific facets, were assessed by self-report. Never-depressed adolescent girls who endorse aNSSI often met lifetime criteria for psychiatric disorders (NSSI: 20/43; 46.5% vs. non-aNSSI: 131/507; 26.1%). aNSSI and lifetime psychopathology were each independently associated with several traits (e.g., high neuroticism and conscientiousness), whereas some traits only discriminated aNSSI (e.g., high melancholia, a facet of neuroticism related to sadness and negative self-evaluation) or lifetime psychopathology independent of each other (e.g., low positive emotionality; low agreeableness). Furthermore, a multivariate model identified high melancholia, high openness to experience, and low conscientiousness as incrementally independent correlates of lifetime aNSSI over and above psychiatric illness. Proneness to melancholia, interest in new things, and poor self-control incrementally track aNSSI in never-depressed adolescent girls. Importantly, this emerges early in course (13–15 years of age) and is independent of lifetime psychiatric diagnosis. Implications for updating etiological models and clinical utility of personality assessment are discussed.     

Development of infant reaching in the dark to luminous objects and 'invisible sounds'

Two studies were conducted to investigate the existence of an unusual U-shaped developmental function described by Wishart et al (1978) for human infants reaching towards invisible sounds. In study 1, 2-7 month olds were presented with four conditions: (i) an invisible auditory stimulus alone, (ii) a glowing visual stimulus alone, (iii) auditory and visual stimuli on the same side (ie combined), and (iv) auditory and visual stimuli on opposite sides (ie in conflict). Study 2 was designed to examine the effects of practice and possible associations made when using the 'combined conflict' paradigm. Infants of 5 and 7 months of age were given five trials with the auditory stimulus, with or without prior visual experience, and five trials with the visual stimulus, with the position of the stimulus varied on each trial. Stimuli were presented individually at the midline, and +/- 30 and +/- 60 degrees from the midline. In both studies testing was conducted in complete darkness. Results indicated that the auditory-alone condition was slower to elicit a reach from the infants, relative to the visual-alone one, and reaches were least frequent to the auditory target. No U-shaped function was obtained, and reaching for auditory targets occurred later in age than for visual targets, but even at 7 months of age did not occur as often and was achieved by fewer infants. In both studies the quality of the reach was significantly poorer to auditory than to visual targets, but there were some accurate reaches. This research adds to our understanding of the development of auditory-manual coordination in sighted infants and is relevant to theories of auditory localization, visually guided reaching, and programming for the blind.     

Do men with excessive alcohol consumption and social stability have an addictive personality?

The existence of an "addictive" personality has been extensively debated. The current study investigated personality in male individuals with excessive alcohol consumption (n=100) in comparison to a population-based control group (n=131). The individuals with excessive alcohol consumption were recruited by advertisements in a regional daily newspaper and controls from a population based Swedish Twin Registry. Personality was assessed by the Karolinska Scales of Personality (KSP). Comparisons were made with normative data. Furthermore, by using a multivariate projection-based approach (Principal Component Analysis; PCA), hidden structures of traits and possible relationships among the individuals with excessive consumption and the controls was investigated. The individuals with excessive alcohol consumption as well as the controls had mean values within the normative range in all scales of the KSP. Moreover, the PCA analysis revealed no systematic between-group separation. Taken together, this result demonstrates that male individuals with excessive alcohol consumption do not have a personality different from that of a general population, which supports the notion of no "addictive personality".     

The role of histone acetylation in age-associated memory impairment and Alzheimer's disease

Learning and memory are cognitive processes that are tightly regulated. A proper genome-environment interaction is a pre-requisite for cognitive function. Epigenetic processes are central regulators of genome-environment interactions. In line with this, it has been shown that the epigenetic machinery is essential for cognitive function. With a specific focus on histone acetylation, we will discuss recent research in the field of epigenetic mechanisms of learning and memory. We will also specifically address the role of histone acetylation in age-associated memory impairment and Alzheimer's disease and ask the question why targeting the epigenome could be a suitable strategy for neuroprotection and neuroregeneration.     

Trial-to-trial sequential dependencies in a social and non-social Simon task

Recent research has shown that joint-action effects in a social Simon task provide a good index of action co-representation. The present study aimed to specify the mechanisms underlying joint action by considering trial-to-trial transitions. Using non-social stimuli, we assigned a Simon task to two participants. Each was responsible for only one of two possible responses. This task was performed alone (Individual go/nogo task) and in cooperation with another person who was sitting alongside (Joint go/nogo task). As a further control task, we added a Standard Simon task. Replicating previous findings (Sebanz et al. in Cognition 88:B11-B21, 2003), we found no spatial compatibility effect in the Individual go/nogo task but we did find one in the Joint go/nogo task. A more detailed analysis showed that a sequential modulation of the Simon effect was present in both the Joint and the Individual go/nogo tasks. We found reliable Simon effects in trials following Simon compatible trials not only in the Joint go/nogo task but also to a somewhat smaller extent in the Individual go/nogo task. For both these go/nogo tasks, sequential modulation effects were stronger for nogo/go transitions than for go/go transitions. This suggests that low-level feature binding and repetition mechanisms contribute to the social Simon effect related to the specific requirement not to respond on nogo trials.     

The Latent Structure of Psychopathy in Youth: A Taxometric Investigation

Using taxometric procedures, the latent structure of psychopathy was investigated in two studies of children and adolescents. Prior studies have identified a taxon (i.e., a natural category) associated with antisocial behavior in adults as well as children and adolescents. However, features of this taxon suggest that it is not psychopathy but rather a broader class consistent with the construct of life course persistent antisocial behavior. Because the only prior study of youth used a non-clinical sample, the base rate of psychopathy may have been too low to reveal a psychopathy taxon, especially against the background of a broader and more prevalent antisocial behavior taxon. Therefore, this investigation sought to increase the likelihood of finding a psychopathy taxon (should one exist) by increasing its expected base rate through inclusion of clinical cases in the samples studied. Results produced evidence for both a broad antisocial behavior problem taxon consistent with past research and a much lower base rate taxon consistent with prevalence expectations for psychopathy. These findings support the existence of latent taxa for both psychopathy and a broader class of antisocial behavior problems. Further taxometric research appears to be warranted, which should use a broader array of indicators, with greater specificity to psychopathy.     

Eyewitness testimony: tracing the beliefs of Swedish legal professionals

This paper examines beliefs held by Swedish legal professionals about eyewitness testimony. In a survey including questions about 13 key issues of eyewitness testimony, three groups were investigated: police officers (n = 104), prosecutors (n = 158), and judges (n = 251). The response rate was 74%. Examples of findings are that the beliefs were in line with scientific findings concerning the weapon focus effect, but were not in line for simultaneous vs. sequential lineups. Between-group differences were found for seven items. Judges were much more sceptical than police officers about the reliability and completeness of children's testimonies. The groups seldom agreed about one answer alternative, and they reported not being up to date about scientific research on eyewitness testimony. The results suggest that some important research findings have reached those working on the field. However, they hold many wrongful beliefs about eyewitness testimony, beliefs that might compromise the accuracy of legal decisions.     

Mechanisms of verbal memory impairment in four neurodevelopmental disorders

Profiles of verbal learning and memory performance were compared for typically developing children and for four developmental disorders characterized by different patterns of language functioning: specific language impairment, early focal brain damage, Williams Syndrome, and Down Syndrome. A list-learning task was used that allowed a detailed examination of the process of verbal learning, recall, and recognition (California Verbal Learning Test--Children's Version). Distinct patterns of performance characterized the four disorders. These patterns were consistent with the language deficits typically seen in the disorders, with the exception of a dissociation seen in Williams Syndrome.     

Animal experimentation

Millions of animals are used every year in oftentimes extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the “3Rs” concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. The licensing of animal experiments normally requires an ethical evaluation process, oftentimes undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees’ members. There is an ongoing societal debate about ethical issues of animal use in science. Existing EU legislation on animal experimentation for cosmetics testing is an example of both the public will for setting clear limits to animal experiments and the need to further critically examine other fields and aspects of animal experimentation. This paper was presented at the 6th International Bioethics Conference on the subject of ‘The Responsible Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005. The paper has been expanded from an article to be published in the forthcoming Council of Europe publication entitled “Animal Protection and Welfare”.