Reducing self-control by weakening belief in free will

Believing in free will may arise from a biological need for control. People induced to disbelieve in free will show impulsive and antisocial tendencies, suggesting a reduction of the willingness to exert self-control. We investigated whether undermining free will affects two aspects of self-control: intentional inhibition and perceived self-control. We exposed participants either to anti-free will or to neutral messages. The two groups (no-free will and control) then performed a task that required self-control to inhibit a prepotent response. No-free will participants showed less intentional inhibitions than controls, suggesting a reduction of self-control. We assessed perceived self-control by asking participants whether the response resulted from a deliberate intention or from an impulsive reaction. Perceived self-control was lower in the no-free will group than in control group. Our findings show that undermining free will can degrade self-control and provide insights into how disbelieving in free will leads to antisocial tendencies.     

Understanding of Genetic Inheritance among Xhosa-Speaking Caretakers of Children with Hemophilia

Hemophilia A and B are X-linked recessive inherited bleeding disorders that have a profound impact on the family of affected individuals. Education is vital to enable women to appreciate the implications of being a carrier and the implications for a prospective child. Prior research has shown that cultural, socio-economic and linguistic issues in South Africa are major barriers to communication for first-language Xhosa-speakers. This exploratory study aimed to investigate the basic knowledge of genetic inheritance among this cultural group in order to promote culturally-sensitive, effective genetic counseling. Ten in-depth interviews were conducted with Xhosa-speaking mothers or caregivers of boys with hemophilia. Results suggest that the participants had a very limited understanding of the clinical management, genetic consequences and cause of hemophilia. While treatment and care by health care service providers was fully accepted, several participants believed that traditional methods would provide them with more satisfactory explanations. These findings suggest that there is a critical need for socio-culturally tailored, language-specific education for families with hemophilia.     

Presymptomatic Testing for Neurogenetic Diseases in Brazil: Assessing Who Seeks and Who Follows through with Testing

Diagnostic tests are available to detect several mutations related to adult-onset, autosomal dominant, neurodegenerative diseases. We aimed to describe our experience in a presymptomatic testing program run by the Brazilian Public Health System from 1999 to 2009. A total of 184 individuals were eligible for presymptomatic testing due to a risk for spinocerebellar ataxia (SCA) - SCA3 (80%), Huntington’s disease (11.9%), familial amyloidotic neuropathy (4.3%), SCA1, SCA2, SCA6, or SCA7. Most were women (70%), married (54%), and had children prior to presymptomatic testing (67%). Their mean age at entrance was 34 (SD = 11 years). Educational level was above the average Brazilian standard. After receipt of genetic counseling, 100 individuals (54%) decided to undergo testing; of these, 51 were carriers. Since no individual returned for post-test psychological evaluation, we conducted a subsequent survey, unrelated to test disclosures. We contacted 57 individuals of whom 31 agreed to participate (24 had been tested, 7 had not). Several ascertainment concerns relating to these numerous losses prevented us from generalizing our results from this second survey. We concluded that: decision-making regarding presymptomatic testing seems to be genuinely autonomous, since after genetic counseling half the individuals who asked for presymptomatic testing decided in favor and half decided against it; general characteristics of Brazilians who sought presymptomatic testing were similar to many European samples studied previously; and individuals at risk for SCA3 may be at greater risk of depression. Although no clear-cut reason emerged for rejection of follow-up psychological sessions after presymptomatic testing, this finding suggests adjustments to our presymptomatic testing program are necessary.     

Is academic buoyancy anything more than adaptive coping?

Academic buoyancy refers to a positive, constructive, and adaptive response to the types of challenges and setbacks experienced in a typical and everyday academic setting. In this project we examined whether academic buoyancy explained any additional variance in test anxiety over and above that explained by coping. Two hundred and ninety-eight students in their final two years of compulsory schooling completed self-report measures of academic buoyancy, coping, and test anxiety. Results suggested that buoyancy was inversely related to test anxiety and unrelated to coping. With the exception of test-irrelevant thoughts, test anxiety was positively related to avoidance coping and social support. Test-irrelevant thoughts were inversely related to task focus, unrelated to social support, and positively related to avoidance. A hierarchical regression analysis showed that academic buoyancy explained a significant additional proportion of variance in test anxiety when the variance for coping had already been accounted for. These findings suggest that academic buoyancy can be considered as a distinct construct from that of adaptive coping.     

Smaller holistic processing of faces associated with face drawing experience

The type of experience involved with an object category has been regarded as one important factor in shaping of the human object recognition system. Laboratory training studies have shown that different kinds of learning experience with the same set of novel objects resulted in different perceptual and neural changes. Whether this applies to natural real-world objects remains to be seen. We compared two groups of observers who had different learning experiences with faces, using holistic processing as a dependent measure. We found that, while ordinary observers had extensive individuation experience with faces and displayed typical holistic face processing, art students who had acquired additional experience in drawing faces, and thus in attending to parts of a face, showed less holistic processing than did ordinary observers. These results converge with laboratory training studies on the role of type of experience in the development of different perceptual markers for different object categories. It is thus insufficient to categorize expertise simply in terms of object domains (e.g., expertise with faces). Instead, perceptual expertise should be classified in terms of the underlying process or task demand.     

An associative model of adaptive inference for learning word-referent mappings

People can learn word–referent pairs over a short series of individually ambiguous situations containing multiple words and referents (Yu & Smith, 2007, Cognition 106: 1558–1568). Cross-situational statistical learning relies on the repeated co-occurrence of words with their intended referents, but simple co-occurrence counts cannot explain the findings. Mutual exclusivity (ME: an assumption of one-to-one mappings) can reduce ambiguity by leveraging prior experience to restrict the number of word–referent pairings considered but can also block learning of non-one-to-one mappings. The present study first trained learners on one-to-one mappings with varying numbers of repetitions. In late training, a new set of word–referent pairs were introduced alongside pretrained pairs; each pretrained pair consistently appeared with a new pair. Results indicate that (1) learners quickly infer new pairs in late training on the basis of their knowledge of pretrained pairs, exhibiting ME; and (2) learners also adaptively relax the ME bias and learn two-to-two mappings involving both pretrained and new words and objects. We present an associative model that accounts for both results using competing familiarity and uncertainty biases.     

Geometric orientation by humans: angles weigh in

Human participants were trained to navigate to two geometrically equivalent corners of a parallelogram-shaped virtual environment. The unique shape of the environment combined three distinct types of geometric information that could be used in combination or in isolation to orient and locate the goals: the angular amplitudes of the corners, the relative wall length relationships, and the principal axis of symmetry. In testing, participants were placed in manipulated versions of the training environment that tested which types of geometry they had encoded and how angular information weighed in against the other two geometric properties. The test environments were (a) a rectangular environment that removed the angular information, (b) a rhombic environment that removed wall length information and drastically reduced the principal axis, and (c) a reverse-parallelogram-shaped environment that placed angular information against both wall length and principal axis information. Participants chose accurately in the rectangular and rhombus environments, despite the removal of one of the cues. In the conflict test, participants preferred corners with the correct angular amplitudes over corners that were correct according to both wall length relationships and the principal axis. These results are comparable to recent findings with pigeons and suggest that angles are a salient orientation cue for humans.     

GABA, glutamate, dopamine and serotonin transporters expression on forgetting

Notwithstanding several neurotransmission systems are frequently related to memory formation; forgetting process and neurotransmission systems or their transporters; the role of γ-aminobutyric acid (GAT1), glutamate (EACC1), dopamine (DAT) and serotonin (SERT) is poorly understood. Hence, in this paper western-blot analysis was used to evaluate expression of GAT1, EAAC1, DAT and SERT during forgetting in trained and untrained rats treated with the selective serotonin transporter inhibitor fluoxetine, the amnesic drug d-methamphetamine (METH) and fluoxetine plus METH. Transporters expression was determined in the hippocampus (HIP), prefrontal cortex (PFC) and striatum (STR). Results indicated that forgetting of Pavlovian/instrumental autoshaping was associated to up-regulation of GAT1 (PFC and HIP) and DAT (PFC) while SERT (HIP) was down-regulated; no-changes were observed in striatum. Methamphetamine administration did not affect forgetting at 216 h post-training but up-regulated hippocampal DAT and EACC, prefrontal cortex DAT and striatal GAT1 or EACC1. Fluoxetine alone prevented forgetting, which was associated to striatal GAT1 and hippocampal DAT up-regulation, but prefrontal cortex GAT1 down-regulation. Fluoxetine plus METH administration was also able to prevent forgetting, which was associated to hippocampal DAT, prefrontal cortex SERT and striatal GAT1, DAT or SERT up-regulation, but prefrontal cortex GAT1 down-regulation. Together these data show that forgetting provokes primarily hippocampal and prefrontal cortex transporters changes; forgetting represent a behavioral process hardly modifiable and its prevention could causes different transporters expression patterns.     

Nitric oxide synthesis in the basolateral complex of the amygdala is required for the consolidation and expression of fear potentiated startle but not shock sensitization of the acoustic startle

Nitric oxide (NO) is synthesized as a result of N-methyl-d-asparate (NMDA) receptor activation, it acts as an retrograde neurotransmitter freely diffusing across cell membranes interacting with its targets in a non-synaptic manner. Consequently, NO has been described as an extension of NMDA receptor activation. The targets of NO include cellular components within the basolateral complex of the amygdala (BLA) that are necessary for the consolidation of conditioned fear as well as targets that can significantly modulate neurotransmission associated with its expression. Given that both are NMDA receptor associated processes, this implies that NO may be an important intermediary of NMDA receptor activation and both fear memory consolidation and expression. The current study sought to examine this using visual fear conditioning and fear potentiated startle. Three experiments were conducted, rats received intra-BLA microinfusions of the global nitric oxide synthase inhibitor l-NAME either prior to fear conditioning, or expression of learned fear. Furthermore, NO's ability to modulate a NMDA receptor independent fear process was assessed by microinfusing l-NAME into the BLA prior to examination of the shock sensitization of the acoustic startle affect. The results indicated that NO was, indeed, required for both the consolidation and expression of learned fear, whereas it was not required for NMDA independent shock enhanced startle responding. This study illustrates that NO plays a pivotal role in the examined NMDA associated fear processes.     

Eye tracking, strategies, and sex differences in virtual navigation

Reports of sex differences in wayfinding have typically used paradigms sensitive to the female advantage (navigation by landmarks) or sensitive to the male advantage (navigation by cardinal directions, Euclidian coordinates, environmental geometry, and absolute distances). The current virtual navigation paradigm allowed both men and women an equal advantage. We studied sex differences by systematically varying the number of landmarks. Eye tracking was used to quantify sex differences in landmark utilisation as participants solved an eight-arm radial maze task within different virtual environments. To solve the task, participants were required to remember the locations of target objects within environments containing 0, 2, 4, 6, or 8 landmarks. We found that, as the number of landmarks available in the environment increases, the proportion of time men and women spend looking at landmarks and the number of landmarks they use to find their way increases. Eye tracking confirmed that women rely more on landmarks to navigate, although landmark fixations were also associated with an increase in task completion time. Sex differences in navigational behaviour occurred only in environments devoid of landmarks and disappeared in environments containing multiple landmarks. Moreover, women showed sustained landmark-oriented gaze, while men's decreased over time. Finally, we found that men and women use spatial and response strategies to the same extent. Together, these results shed new light on the discrepancy in landmark utilisation between men and women and help explain the differences in navigational behaviour previously reported.