From rat sexual behavior to schizophrenia: a tribute to Professor Emeritus Knut Larsson

In July of 2002 Knut Larsson celebrated his 80th birthday. He could by then have looked back at a long and distingusihed career in the field of biological psychology. His research on sexual behavior had contributed to a basic understanding of many behavioral, endocrine and neural phenomena associated with or underlying sexual activity. Instead of looking back at his past achievements, Knut has preferred to look forward, constantly trying to find ways to stimulate interest in his own field and in biological psychology in general. This issue is a humble contribution to the noble end of enhancing the standing of biological psychology, particularly in Scandinavia. Foremost, however, it is a homage to a man of outstanding vision and intellectual integrity: Knut Larsson.     

Working memory deficits in transgenic rats overexpressing human adenosine A2A receptors in the brain

Adenosine receptors in the central nervous system have been implicated in the modulation of different behavioural patterns and cognitive functions although the specific role of A(2A) receptor (A(2A)R) subtype in learning and memory is still unclear. In the present work we establish a novel transgenic rat strain, TGR(NSEhA2A), overexpressing adenosine A(2A)Rs mainly in the cerebral cortex, the hippocampal formation, and the cerebellum. Thereafter, we explore the relevance of this A(2A)Rs overexpression for learning and memory function. Animals were behaviourally assessed in several learning and memory tasks (6-arms radial tunnel maze, T-maze, object recognition, and several Morris water maze paradigms) and other tests for spontaneous motor activity (open field, hexagonal tunnel maze) and anxiety (plus maze) as modification of these behaviours may interfere with the assessment of cognitive function. Neither motor performance and emotional/anxious-like behaviours were altered by overexpression of A(2A)Rs. TGR(NSEhA2A) showed normal hippocampal-dependent learning of spatial reference memory. However, they presented working memory deficits as detected by performance of constant errors in the blind arms of the 6 arm radial tunnel maze, reduced recognition of a novel object and a lack of learning improvement over four trials on the same day which was not observed over consecutive days in a repeated acquisition paradigm in the Morris water maze. Given the interdependence between adenosinic and dopaminergic function, the present results render the novel TGR(NSEhA2A) as a putative animal model for the working memory deficits and cognitive disruptions related to overstimulation of cortical A(2A)Rs or to dopaminergic prefrontal dysfunction as seen in schizophrenic or Parkinson's disease patients.     

Socio-demographic and psychopathological risk factors in obsessive-compulsive disorder: Epidemiologic study of school population

We assessed the presence of emotional disorders (obsessive-compulsive, anxiety and depressive) in 1,514 Spanish non-referred children (8–12 years old) to investigate the predictive ability of psychopathological and socio-demographic characteristics, and identify which of these were possible correlates for clinical obsessive-compulsive disorder (OCD) and subclinical OCD. At one year later, 562 subjects (risk group and without risk group) were re-assessed and we established the OCD diagnoses or the subclinical OCD diagnoses. We found that 20 participants presented clinical OCD and 46 participants presented subclinical OCD. Somatic and separation anxiety symptomatology were good predictors for clinical OCD, and obsessive concern was a predictor for subclinical OCD. Clinical OCD was associated with order/checking/pollution symptoms and with a lower socioeconomic status (SES). Subclinical OCD was associated with hyperactive and impulsive manifestations, obsessive concern, and superstition/mental compulsion. An early detection and the follow-up of anxiety or obsessive symptoms in children may be important for preventing the course of OCD.     

The impact of COVID-19 concerns on perceiving others' faces

Unlike most infectious diseases, COVID-19 is characterised by an absence of facial disease-signalling cues. Yet, it is still unclear whether it has influenced face perception. Understanding this may help clarify if and how our motivation toward social interactions is conditional on situational pathogen threats. The present study investigated if priming disease concerns about COVID-19 would change people's perception of neutral faces on perceived disease, social discomfort and arousal elicited by such faces; this condition was compared with other infectious/non-infectious diseases and a non-disease priming condition. One-hundred sixty-six participants recruited nationally performed the online task. When compared with the non-disease condition, participants primed for COVID-19 perceived faces as sicker and tended to view them as eliciting more social discomfort; no difference occurred in arousal. No other difference was found between conditions. These findings suggest that the pandemic context can shape how we perceive others' apparent sickness. Overall, these might reflect adaptations intertwined with the behavioural immune system's defence mechanisms.     

Psychological problems and associated factors at 6 years of age: differences between sexes

In a non-clinical group of 130 children (65 boys and 65 girls), we evaluated the relationships between psychological problems using the Child Behavior Checklist (CBCL) reported by parents, the Inattention Overactivity With Aggression (IOWA) scale reported by teachers, individual factors (Intellectual quotient [IQ], temperament and heart rate) and environmental factors (stress events, mother's profession and being or not being an only child). We found no differences between the sexes in the prevalence of total psychological problems in the clinical range, but girls had significantly more borderline total problems than boys. Girls tended to have more externalizing problems than boys. In boys, there were more links between individual and environmental factors and psychological problems, especially externalizing problems. A high score in psychological problems assessed by the CBCL affected the school performance of boys and the social performance of girls. For boys, IQ was significantly lower when the score for total behavioral problems was higher, and for girls IQ was significantly lower when the score for externalizing problems was higher. Understanding the different levels of vulnerability of the sexes at different periods of development may help to improve the treatment children in this age group receive.     

Doing without representing?

Connectionism and classicism, it generally appears, have at least this much in common: both place some notion of internal representation at the heart of a scientific study of mind. In recent years, however, a much more radical view has gained increasing popularity. This view calls into question the commitment to internal representation itself. More strikingly still, this new wave of anti-representationalism is rooted not in armchair theorizing but in practical attempts to model and understand intelligent, adaptive behavior. In this paper we first present, and then critically assess, a variety of recent anti-representationalist treatments. We suggest that so far, at least, the sceptical rhetoric outpaces both evidence and argument. Some probable causes of this premature scepticism are isolated. Nonetheless, the anti-representationalist challenge is shown to be both important and progressive insofar as it forces us to see beyond the bare representational/non-representational dichotomy and to recognize instead a rich continuum of degrees and types of representationality.     

Adaptive memory: survival processing enhances retention

The authors investigated the idea that memory systems might have evolved to help us remember fitness-relevant information--specifically, information relevant to survival. In 4 incidental learning experiments, people were asked to rate common nouns for their survival relevance (e.g., in securing food, water, or protection from predators); in control conditions, the same words were rated for pleasantness, relevance to moving to a foreign land, or personal relevance. In surprise retention tests, participants consistently showed the best memory when words were rated for survival; the survival advantage held across recall, recognition, and for both within-subject and between-subjects designs. These findings suggest that memory systems are "tuned" to remember information that is processed for fitness, perhaps as a result of survival advantages accrued in the past.     

Dialectical behaviour therapy skills training compared to standard group therapy in borderline personality disorder: A 3-month randomised controlled clinical trial

Dialectical behaviour therapy (DBT) has proven to be an effective treatment in borderline personality disorder (BPD). However, the effectiveness in BPD of DBT skills training (DBT-ST) alone is not known. This study aimed at comparing the efficacy of DBT-ST and standard group therapy (SGT) for outpatients with BPD. Sixty patients meeting the DSM-IV diagnostic criteria for BPD, as assessed by two semi-structured diagnostic interviews, were included in a 3-month, single-blind randomised controlled trial. A total of 13 weekly group psychotherapy sessions of 120 min of either SGT or DBT-ST were conducted. Assessments were carried out every 2 weeks by two blinded evaluators. Observer-rater, self-report scales and behavioural reports were used as outcome measures. DBT-ST was associated with lower dropout rates, 34.5% compared to 63.4% with SGT. It was superior to SGT in improving several mood and emotion areas, such as: depression, anxiety, irritability, anger and affect instability. A reduction in general psychiatric symptoms was also observed. Three-months weekly DBT-ST proved useful. This therapy was associated with greater clinical improvements and lower dropout rates than SGT. DBT-ST seems to play a role in the overall improvement of BPD seen with standard DBT intervention. It allows straightforward implementation in a wide range of mental health settings and provides the additional advantage that it is cost effective.