Simulation,simplicity, and selection: an evolutionary perspective on high-level mindreading

In this paper, I argue that a natural selection-based perspective gives reasons for thinking that the core of the ability to mindread cognitively complex mental states is subserved by a simulationist process—that is, that it relies on non-specialised mechanisms in the attributer’s cognitive architecture whose primary function is the generation of her own decisions and inferences. In more detail, I try to establish three conclusions. First, I try to make clearer what the dispute between simulationist and non-simulationist theories of mindreading fundamentally is about. Second, I try to make more precise an argument that is sometimes hinted at in support of the former: this ‘argument from simplicity’ suggests that, since natural selection disfavours building extra cognitive systems where this can be avoided, simulationist theories of mindreading are more in line with natural selection than their competitors. As stated, though, this argument overlooks the fact that building extra cognitive systems can also yield benefits: in particular, it can allow for the parallel processing of multiple problems and it makes for the existence of backups for important elements of the organism’s mind. I therefore try to make this argument more precise by investigating whether these benefits also apply to the present case—and conclude negatively. My third aim in this paper is to use this discussion of mindreading as a means for exploring the promises and difficulties of evolutionary arguments in philosophy and psychology more generally.     

Predicting First Graders' Development of Calculation versus Word-Problem Performance: The Role of Dynamic Assessment

The purpose of this study was to assess the value of dynamic assessment (DA; degree of scaffolding required to learn unfamiliar mathematics content) for predicting 1(st)-grade calculations (CA) and word problems (WP) development, while controlling for the role of traditional assessments. Among 184 1(st) graders, predictors (DA, Quantity Discrimination, Test of Mathematics Ability, language, and reasoning) were assessed near the start of 1(st) grade. CA and WP were assessed near the end of 1(st) grade. Planned regression and commonality analyses indicated that for forecasting CA development, Quantity Discrimination, which accounted for 8.84% of explained variance, was the single most powerful predictor, followed by Test of Mathematics Ability and DA; language and reasoning were not uniquely predictive. By contrast, for predicting WP development, DA was the single most powerful predictor, which accounted for 12.01% of explained variance, with Test of Mathematics Ability, Quantity Discrimination, and language also uniquely predictive. Results suggest that different constellations of cognitive resources are required for CA versus WP development and that DA may be useful in predicting 1(st)-grade mathematics development, especially WP.     

Contributions of domain-general cognitive resources and different forms of arithmetic development to pre-algebraic knowledge

The purpose of this study was to investigate the contributions of domain-general cognitive resources and different forms of arithmetic development to individual differences in pre-algebraic knowledge. Children (n = 279, mean age = 7.59 years) were assessed on 7 domain-general cognitive resources as well as arithmetic calculations and word problems at start of 2nd grade and on calculations, word problems, and pre-algebraic knowledge at end of 3rd grade. Multilevel path analysis, controlling for instructional effects associated with the sequence of classrooms in which students were nested across Grades 2-3, indicated arithmetic calculations and word problems are foundational to pre-algebraic knowledge. Also, results revealed direct contributions of nonverbal reasoning and oral language to pre-algebraic knowledge, beyond indirect effects that are mediated via arithmetic calculations and word problems. By contrast, attentive behavior, phonological processing, and processing speed contributed to pre-algebraic knowledge only indirectly via arithmetic calculations and word problems. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Juvenile stress potentiates aversive 22-kHz ultrasonic vocalizations and freezing during auditory fear conditioning in adult male rats

Traumatic experiences that occur during adolescence can render individuals vulnerable to mood and anxiety disorders. A model in juvenile rats (age: 27-29 days) was developed previously to study the long-term effects of adolescent stress exposure on behaviour and physiology. This paradigm, termed juvenile stress, involves subjecting juvenile rats to different stressors on consecutive days over a 3-day period. Here, we investigated the effects of the juvenile stress paradigm on freezing behaviour and aversive 22-kHz ultrasonic vocalizations (USVs) during auditory fear conditioning in adult male rats (age: 68-90 days). We found that rats previously subjected to juvenile stress increased aversive 22-kHz USVs (total calls and time spent calling) compared with controls during fear-conditioning training. The acoustic USV parameters between control and juvenile stress rats were largely equivalent, including duration, peak frequency and amplitude. While rats did not differ in freezing behaviour during fear conditioning, juvenile stress rats exhibited greater cue-conditioned freezing upon testing 24 h later. Our results show that juvenile stress elicited different long-term changes in freezing and aversive USVs during fear conditioning. Furthermore, they highlight the importance of assessing USVs to detect experience-dependent differences between control and stress-exposed animals which are not detectable by measuring visible behaviour.     

13 Perspective: Suicide in Europe

In many European countries, suicidal behavior constitutes a major public and mental health problem. In most countries, the number of suicides is significantly higher than the number of deaths due to traffic accidents. According to official figures, the suicide rates among European countries differ widely; for example, Hungary has the highest rates. Suicide attempt rates, based on data from the WHO/Euro Multicentre project on Parasuicide, equally show variation; for example, the highest average rate of suicide attempts is for Helsinki, Finland. This paper outlines the epidemiological findings and then presents some hypotheses (e.g., age, ethnic difference) to explain the differences.