Neurocognitive Functioning in Depressed Young People: A Systematic Review and Meta-Analysis

Background: Depression is among the most common mental health problems for young people. In adults, depression is associated with neurocognitive deficits that reduce the effectiveness of treatment and impair educational and vocational functioning. Compared to adults, less is known about the neurocognitive functioning of young people with depression, and existing research has reported inconsistent findings. Method: This systematic review and meta-analysis synthesized the literature on neurocognitive functioning in currently depressed youth aged 12–25 years in comparison to healthy controls. Results: Following a systematic review of the literature, 23 studies were included in the meta-analysis. Poorer performance in the domains of attention (SMD: .50, 95% CI: .18–.83, p?=?.002), verbal memory (SMD: .78, 95% CI: .50–1.0, p?<?.001), visual memory (SMD: .65, 95% CI: .30–.99, p?<?.001), verbal reasoning/knowledge (SMD: .46; 95% CI: .14–.79; p?<?0.001) and IQ (SMD: .32; 95% CI: .08–.56; p?=?0.01) were identified in depressed youth. Relative weaknesses in processing speed/reaction time and verbal learning were also evident, however, these findings disappeared when the quality of studies was controlled for. Moderator analysis showed a tendency for poorer set-shifting ability in younger depressed participants relative to controls (although non-significant; p?=?.05). Moderator analysis of medication status showed taking medication was associated with poorer attentional functioning compared to those not taking medication. Conclusion: The findings suggest that currently depressed young people display a range of neurocognitive weaknesses which may impact treatment engagement and outcome. The findings support the need to consider neurocognitive functioning when treating youth with depression.     

The City Infant Faces Database: A validated set of infant facial expressions

Adults need to be able to process infants’ emotional expressions accurately to respond appropriately and care for infants. However, research on processing of the emotional expressions of infant faces is hampered by the lack of validated stimuli. Although many sets of photographs of adult faces are available to researchers, there are no corresponding sets of photographs of infant faces. We therefore developed and validated a database of infant faces, which is available via e-mail request. Parents were recruited via social media and asked to send photographs of their infant (0–12 months of age) showing positive, negative, and neutral facial expressions. A total of 195 infant faces were obtained and validated. To validate the images, student midwives and nurses (n = 53) and members of the general public (n = 18) rated each image with respect to its facial expression, intensity of expression, clarity of expression, genuineness of expression, and valence. On the basis of these ratings, a total of 154 images with rating agreements of at least 75% were included in the final database. These comprise 60 photographs of positive infant faces, 54 photographs of negative infant faces, and 40 photographs of neutral infant faces. The images have high criterion validity and good test–retest reliability. This database is therefore a useful and valid tool for researchers.     

Fechner, information, and shape perception

How do retinal images lead to perceived environmental objects? Vision involves a series of spatial and material transformations—from environmental objects to retinal images, to neurophysiological patterns, and finally to perceptual experience and action. A rationale for understanding functional relations among these physically different systems occurred to Gustav Fechner: Differences in sensation correspond to differences in physical stimulation. The concept of information is similar: Relationships in one system may correspond to, and thus represent, those in another. Criteria for identifying and evaluating information include (a)?resolution, or the precision of correspondence; (b)?uncertainty about which input (output) produced a given output (input); and (c)?invariance, or the preservation of correspondence under transformations of input and output. We apply this framework to psychophysical evidence to identify visual information for perceiving surfaces. The elementary spatial structure shared by objects and images is the second-order differential structure of local surface shape. Experiments have shown that human vision is directly sensitive to this higher-order spatial information from interimage disparities (stereopsis and motion parallax), boundary contours, texture, shading, and combined variables. Psychophysical evidence contradicts other common ideas about retinal information for spatial vision and object perception.