Developmental changes of sleep spindles and their impact on sleep‐dependent memory consolidation and general cognitive abilities: A longitudinal approach

Sleep spindles are related to sleep‐dependent memory consolidation and general cognitive abilities. However, they undergo drastic maturational changes during adolescence. Here we used a longitudinal approach (across 7 years) to explore whether developmental changes in sleep spindle density can explain individual differences in sleep‐dependent memory consolidation and general cognitive abilities. Ambulatory polysomnography was recorded during four nights in 34 healthy subjects (24 female) with two nights (baseline and experimental) at initial recording (age range 8–11 years) and two nights at follow‐up recording (age range 14–18 years). For declarative learning, participants encoded word pairs with a subsequent recall before and after sleep. General cognitive abilities were measured by the Wechsler Intelligence Scale. Higher slow (11–13 Hz) than fast (13–15 Hz) spindle density at frontal, central, and parietal sites during initial recordings, followed by a shift to higher fast than slow spindle density at central and parietal sites during follow‐up recordings, suggest that mature spindle topography develops throughout adolescence. Fast spindle density increases from baseline to experimental night were positively related to sleep‐dependent memory consolidation. In addition, we found that the development of fast spindles predicted the improvement in memory consolidation across the two longitudinal measurements, a finding that underlines a crucial role for mature fast spindles for sleep‐dependent memory consolidation. Furthermore, slow spindle changes across adolescence were related to general cognitive abilities, a relationship that could indicate the maturation of frontal networks relevant for efficient cognitive processing. A video abstract of this article can be viewed at: https://www.youtube.com/watch?v=7NXJzm8HbIw and https://www.youtube.com/watch?v=iuMQY1OIJ0s     

“Weak,Sad, and Lazy Fatties”: Adolescents’ Explicit and Implicit Weight Bias Following Exposure to Weight Loss Reality TV Shows

Weight loss reality TV shows, which portray obese individuals and their struggle to lose weight, are highly popular. However, the shows often contain negative and stereotypical portrayals of obese individuals that can contribute to the formation of weight bias among viewers. In particular, adolescents might be highly susceptible to such portrayals, since physical appearance and body image play an important role during adolescence. In our experimental study, we investigated the priming effects of exposure to weight loss reality TV shows on implicit and explicit attitudes toward obese individuals among 353 adolescents. We exposed a treatment group (n = 173) to video clips of a weight loss reality TV show and a control group (n = 180) to video clips of an information-based TV magazine. Results indicated that for individuals who expressed a fear of being obese, exposure to the weight loss reality TV show reinforced negative explicit attitudes toward obese individuals by activating a perception of weight controllability. Exposure to the weight loss reality TV show also enhanced negative implicit attitudes toward obese individuals among all adolescents, irrespective of their fear of being obese. Altogether, our findings underscore the role of media in perpetuating weight bias.     

Inhibitory and facilitatory location priming in patients with left-sided visual hemi-neglect

In visual search for pop-out targets, reaction times are facilitated when the target on the current trial appears at a previous target location, and inhibited when it appears at a previous distractor location, relative to when it appears at a previously empty (neutral) location (Maljkovic and Nakayama, Perception and Psychophysics 58:977–991, 1996). However, while normal subjects are able to positively/negatively tag selected target/rejected distractor locations to guide search on the next trial, patients with visual hemi-neglect may have a (uni- or bilateral) deficit in these functions that may contribute to their disturbed visual scanning behavior. To examine this, using a pop-out search task, the present study assessed cross-trial facilitatory and inhibitory priming in 14 patients with left-sided visual hemi-neglect and in 14 age-, education-, and IQ-matched control subjects. The group of neglect patients did show significant facilitatory and inhibitory priming. However, while control subjects exhibited balanced effects of facilitation and inhibition, inhibition was relatively reduced in magnitude in neglect patients. In particular, inhibition was virtually absent in two patients with lesions affecting superior regions of the frontal cortex, putatively encroaching on the frontal eye field of the right hemisphere. These findings provide neuropsychological evidence that facilitatory and inhibitory priming effects are based on dissociable mechanisms, consistent with Geyer et al. (Journal of Experimental Psychology: Human Perception and Performance 33:788–797, 2007).     

Brain correlates of early auditory processing are attenuated by expectations for time and pitch

The present study investigated how auditory processing is modulated by expectations for time and pitch by analyzing reaction times and event-related potentials (ERPs). In two experiments, tone sequences were presented to the participants, who had to discriminate whether the last tone of the sequence contained a short gap or was continuous (Experiment 1: go/nogo, Experiment 2: choice reaction). Expectations were induced by varying the temporal and pitch regularity of the sequence. Results were consistent across both experiments. Expectations for both time and pitch were associated with faster responding. Both temporal and pitch expectations led to an attenuation of the auditory N1, thus indicating a modulation of early, perceptual processing by temporal and pitch expectations. Effects of temporal expectations were also evident in a P300-like deflection, suggesting that temporal expectations also affect decision- or response-related processing stages.     

Avoidance of emotional facial expressions in social anxiety: The Approach-Avoidance Task

The Approach–Avoidance Task (AAT) was employed to indirectly investigate avoidance reactions to stimuli of potential social threat. Forty-three highly socially anxious individuals (HSAs) and 43 non-anxious controls (NACs) reacted to pictures of emotional facial expressions (angry, neutral, or smiling) or to control pictures (puzzles) by pulling a joystick towards themselves (approach) versus pushing it away from themselves (avoidance). HSAs showed stronger avoidance tendencies than NACs for smiling as well as angry faces, whereas no group differences were found for neutral faces and puzzles. In contrast, valence ratings of the emotional facial expressions did not differ between groups. A critical discrepancy between direct and indirect measures was observed for smiling faces: HSAs evaluated them positively, but reacted to them with avoidance.     

A review of applicant faking in selection interviews

Interviews are commonly used for selection but research on interview faking only gained momentum relatively recently. We review both theoretical and empirical work on prevalence, antecedents, processes, and effects of interview faking. Most applicants fake at least to some degree. Personality (e.g., Conscientiousness, Honesty‐humility, the Dark Triad) and attitudes toward faking substantially correlate with faking behaviors. Research concerning applicants' ability, interview structure components, or contextual factors is limited. Furthermore, the impact of faking on interview ratings is mixed and effects on criterion‐related validity are not consistently negative. Finally, the detection of faking seems hardly possible and there are limited options available to reduce interview faking. Throughout our review, we describe important gaps and derive suggestions and propositions for future research.     

Themes of Self‐Regulation and Self‐Exploration in the Life Stories of Religious American Conservatives and Liberals

A sample of 128 highly religious (Christian) midlife American adults completed a series of attitudinal and personality trait measures and narrated 12 important autobiographical scenes in their life stories. Individuals high on self‐reported political conservatism tended to accentuate the theme of self‐regulation in their life stories, repeatedly describing important autobiographical scenes wherein they struggled to control, discipline, manage, restrain, protect, or preserve the self. By contrast, individuals high on political liberalism tended to emphasize the theme of self‐exploration, telling stories about expanding, discovering, articulating, or fulfilling the self. Demographics and dispositional traits (especially openness to experience) showed significant associations with conservatism‐liberalism, as well, but these variables did not mitigate the robust relationship between life‐narrative themes and political orientation. The results are discussed in terms of a broadened understanding of personality that conceives of dispositional traits and narrative identity as comprising distinct layers and complementary features of psychological individuality, both implicated in political lives.     

Inhibition of return is unimpressed by emotional cues

Inhibition of return (IOR) is a phenomenon observed when a target unexpectedly appears in the place of a preceding cue: With long cue–target stimulus onset asynchronies, reaction times are longer than for targets that appear in an alternative location. Cognitive theories of anxiety suppose that the IOR effect diminishes with threatening, biologically relevant cues because these catch and hold attention. To test this hypothesis, we conducted three experiments, in which emotional valence of cues (animals or facial expressions) had no influence on the strength of the IOR effect, neither in an unselected sample of students nor in highly spider-fearful or socially anxious participants. Inhibition of return appears to be a robust effect, blind to cue valence.     

Adult but not juvenile Barbary macaques spontaneously recognize group members from pictures

For group-living animals, it is crucial to distinguish one’s own group members from those of other groups. Studies applying operant conditioning revealed that monkeys living in relatively small groups are able to recognize their own group members when tested with photographs of group members and other conspecifics. Employing a simple looking time paradigm, we here show that Barbary macaques living in two social groups comprising 46 and 57 individuals, respectively, at the enclosure ‘La Forêt des Singes’ at Rocamadour are able to spontaneously distinguish photographs of members of their own group from those depicting animals that belong to another group. This ability appears to develop with age, as juveniles did not discriminate between members of their own group and another group, although they showed generally more interest in the pictures than did adults. Juveniles frequently displayed picture directed behaviours such as lip-smacking, touching and sniffing in both conditions, indicating that the stimuli were highly salient to them. In conclusion, it appears that at least adult monkeys are able to memorize the faces of a large number of individuals. Whether the difference in behaviour is based on individual recognition of one’s own group members or simply the discrimination based on familiarity remains unresolved. However, both mechanisms would be sufficient for group membership identification.