The effect of spatial frequency information and visual similarity in threat detection

In the current research, we sought to examine the role of spatial frequency on the detection of threat using a speeded visual search paradigm. Participants searched for threat-relevant (snakes or spiders) or non-threat-relevant (frogs or cockroaches) targets in an array of neutral (flowers or mushrooms) distracters, and we measured search performance with images filtered to contain different levels (high and low) of spatial frequency information. The results replicate previous work demonstrating more rapid detection of threatening versus non-threatening stimuli [e.g. LoBue, V. & DeLoache, J. S. (2008). Detecting the snake in the grass: Attention to fear-relevant stimuli by adults and young children. Psychological Science, 19, 284–289. doi:10.1111/j.1467-9280.2008.02081.x]. Most importantly, the results suggest that low spatial frequency or relatively coarse levels of visual information is sufficient for the rapid and accurate detection of threatening stimuli. Furthermore, the results also suggest that visual similarity between the stimuli used in the search tasks plays a significant role in speeded detection. The results are discussed in terms of the theoretical implications for the rapid detection of threat and methodological implications for properly accounting for similarity between the stimuli in visual search studies.     

Sleep deprivation in adolescents and adults: changes in affect

The present study investigated the impact of sleep deprivation on several aspects of affective functioning in healthy participants selected from three different developmental periods: early adolescence (ages 10-13), midadolescence (ages 13-16), and adulthood (ages 30-60). Participants completed an affective functioning battery under conditions of sleep deprivation (a maximum of 6.5 hours total sleep time on the first night followed by a maximum of 2 hours total sleep time on the second night) and rest (approximately 7-8 hours total sleep time each night for two consecutive nights). Less positive affect was observed in the sleep-deprived, compared to rested, condition. This effect held for 9 of the 12 positive affect items on the PANAS-C. Participants also reported a greater increase in anxiety during a catastrophizing task and rated the likelihood of potential catastrophes as higher when sleep deprived, relative to when rested. Early adolescents appraised their main worry as more threatening when sleep deprived, relative to when rested. These results support and extend previous research underscoring the adverse affective consequences of sleep deprivation.     

Context processing in schizotypal personality disorder: evidence of specificity of impairment to the schizophrenia spectrum

Working memory abnormalities, which are particularly pronounced on context processing tasks, appear relatively specific to schizophrenia spectrum illnesses compared with other psychotic disorders. However, the specificity of context processing deficits to schizotypal personality disorder (SPD), a prototype of schizophrenia, has not been studied. The authors administered 3 versions of the modified AX Continuous Performance Test and an N-back working memory test to 63 individuals with SPD and 25 with other personality disorders, as well as 42 healthy controls. For the AX Continuous Performance Test standard and degraded versions, there was a significant Trial Type x Delay x Group interaction, as SPDs made significantly more errors reflecting poor maintenance of context and fewer errors reflecting good maintenance of context. SPDs also demonstrated poor performance on the N-back, especially at the 2-back condition. Context processing errors and N-back accuracy scores were related to disorganization symptoms. These findings, which are quite similar to those previously reported in patients with schizophrenia, suggest that context processing deficits are specific to the schizophrenia spectrum and are not a reflection of overall psychopathology.     

Transdiagnostic emotion regulation processes in bipolar disorder and insomnia

Research and treatment have traditionally adopted a 'disorder-focused' approach by targeting one specific disorder, aiming to understanding its cause, maintenance and treatment. The aim of the present study was to contribute to the burgeoning interest in examining common, or 'transdiagnostic,' processes across disorders. Three candidate transdiagnostic processes involved in emotion regulation - rumination, worry, and automatic negative thoughts - were examined in euthymic bipolar I disorder (n=21) and insomnia (n=19), and a non-clinical control group (n=20). Rumination and worry were endorsed to a larger degree by the bipolar and insomnia groups compared to the control group. However, while the bipolar group had more negative automatic thoughts than the control group, there were no significant differences in negative automatic thoughts between the bipolar and insomnia groups or the insomnia and control groups. These results suggested that rumination and worry, but not negative automatic thoughts, might be common across bipolar disorder and insomnia. However, these findings no longer remained significant when current symptoms of anxiety and depression were controlled for. Prospective and experimental studies are needed to test the extent to which these processes contribute to the etiology or maintenance of insomnia and bipolar disorder.     

Behavioral consistency in a changed social context in Carolina chickadees

Stable personality-like influences on behavior have been documented in nonhuman animals (S. D. Gosling, 2001), but little is known about such influences within explicitly social contexts. The authors tested whether individuals of a socially complex avian species, Carolina chickadees (Poecile carolinensis), show consistent behavioral profiles when their social context changes. Consistency was tested using 7 groups of chickadees, each group comprising 2 female-male pairs. The 2 pairs from each group were isolated from one another until the male birds were switched between the pairs. The authors made several measures before and after the male switch, including measures of affiliative and agonistic behavior, self-maintenance behavior, and vocalizations. The authors observed strong behavioral consistency despite the major change in social context, suggesting that personality can influence this fundamental social relationship.     

Pharmacological Cognitive Enhancement in Schizophrenia

Cognitive impairments in schizophrenia are common and severe. These impairments are also related to functional disability in schizophrenia. As a result, efforts are underway to enhance cognition in schizophrenia through a variety of pharmacological mechanisms. As part of this effort, a designated research design has been developed for this process, through an extensive consensus and validation effort. This paper reviews the methods for pharmacological cognitive enhancement, as well as previous results of efforts in the pharmacological domains. These domains include cholinergic, noradrenergic, serotonergic, glutamatergic, and GABA-ergic mechanisms. While previous results have not been particularly encouraging, there are many challenges that need to be overcome and many of the reasons for past failures may be due to resolvable issues. It is likely that this will be an area of research that will be developing extensively over the next decade and expanding to other conditions as well.