Cortical brain regions engaged by masked emotional faces in adolescents and adults: an fMRI study

Face-emotion processing has shown signs of developmental change during adolescence. Functional magnetic resonance imaging (fMRI) was used on 10 adolescents and 10 adults to contrast brain regions engaged by a masked emotional-face task (viewing a fixation cross and a series of masked happy and masked fearful faces), while blood oxygen level dependent signal was monitored by a 1.5-T MRI scanner. Brain regions differentially engaged in the 2 age groups were mapped by using statistical parametric mapping. Summed across groups, the contrast of masked face versus fixation-cross viewing generated activations in occipital-temporal regions previously activated in passive face-viewing tasks. Adolescents showed higher maxima for activations in posterior association cortex for 3 of the 4 statistical contrasts. Adolescents and adults differed in the degree to which posterior hemisphere brain areas were engaged by viewing masked facial displays of emotion.     

Giving cognition a helping hand: The effect of congruent gestures on object name retrieval

The gestures that accompany speech are more than just arbitrary hand movements or communicative devices. They are simulated actions that can both prime and facilitate speech and cognition. This study measured participants’ reaction times for naming degraded images of objects when simultaneously adopting a gesture that was either congruent with the target object, incongruent with it, and when not making any hand gesture. A within‐subjects design was used, with participants (N= 122) naming 10 objects under each condition. Participants named the objects significantly faster when adopting a congruent gesture than when not gesturing at all. Adopting an incongruent gesture resulted in significantly slower naming times. The findings are discussed in the context of the intrapersonal cognitive and facilitatory effects of gestures and underline the relatedness between language, action, and cognition.     

Why computational models are better than verbal theories: the case of nonword repetition

Tests of nonword repetition (NWR) have often been used to examine children's phonological knowledge and word learning abilities. However, theories of NWR primarily explain performance either in terms of phonological working memory or long‐term knowledge, with little consideration of how these processes interact. One theoretical account that focuses specifically on the interaction between short‐term and long‐term memory is the chunking hypothesis. Chunking occurs because of repeated exposure to meaningful stimulus items, resulting in the items becoming grouped (or chunked); once chunked, the items can be represented in short‐term memory using one chunk rather than one chunk per item. We tested several predictions of the chunking hypothesis by presenting 5–6‐year‐old children with three tests of NWR that were either high, medium, or low in wordlikeness. The results did not show strong support for the chunking hypothesis, suggesting that chunking fails to fully explain children's NWR behavior. However, simulations using a computational implementation of chunking (namely CLASSIC, or Chunking Lexical And Sub‐lexical Sequences In Children) show that, when the linguistic input to 5–6‐year‐old children is estimated in a reasonable way, the children's data are matched across all three NWR tests. These results have three implications for the field: (a) a chunking account can explain key NWR phenomena in 5–6‐year‐old children; (b) tests of chunking accounts require a detailed specification both of the chunking mechanism itself and of the input on which the chunking mechanism operates; and (c) verbal theories emphasizing the role of long‐term knowledge (such as chunking) are not precise enough to make detailed predictions about experimental data, but computational implementations of the theories can bridge the gap.     

ArduiPod Box: A low-cost and open-source Skinner box using an iPod Touch and an Arduino microcontroller

This article introduces the ArduiPod Box, an open-source device built using two main components (i.e., an iPod Touch and an Arduino microcontroller), developed as a low-cost alternative to the standard operant conditioning chamber, or “Skinner box.” Because of its affordability, the ArduiPod Box provides an opportunity for educational institutions with small budgets seeking to set up animal laboratories for research and instructional purposes. A pilot experiment is also presented, which shows that the ArduiPod Box, in spite of its extraordinary simplicity, can be effectively used to study animal learning and behavior.     

Predictors of Sleep-Problem Trajectories Across Adolescence

Research on Child and Adolescent Psychopathology - Stress and sleep problems are significantly correlated in adolescents. Few longitudinal studies, however, have evaluated possible correlates and...     

A developmental neuroimaging investigation of the change paradigm

This neuroimaging study examines the development of cognitive flexibility using the Change task in a sample of youths and adults. The Change task requires subjects to inhibit a prepotent response and substitute an alternative response, and the task incorporates an algorithm that adjusts task difficulty in response to subject performance. Data from both groups combined show a network of prefrontal and parietal areas that are active during the task. For adults vs. youths, a distributed network was more active for successful change trials versus go, baseline, or unsuccessful change trials. This network included areas involved in rule representation, retrieval (lateral PFC), and switching (medial PFC and parietal regions). These results are consistent with data from previous task-switching experiments and inform developmental understandings of cognitive flexibility.     

Attention Biases to Threat Link Behavioral Inhibition to Social Withdrawal over Time in Very Young Children

Behaviorally inhibited children display a temperamental profile characterized by social withdrawal and anxious behaviors. Previous research, focused largely on adolescents, suggests that attention biases to threat may sustain high levels of behavioral inhibition (BI) over time, helping link early temperament to social outcomes. However, no prior studies examine the association between attention bias and BI before adolescence. The current study examined the interrelations among BI, attention biases to threat, and social withdrawal already manifest in early childhood. Children (N = 187, 83 Male, M _age  = 61.96 months) were characterized for BI in toddlerhood (24 & 36 months). At 5 years, they completed an attention bias task and concurrent social withdrawal was measured. As expected, BI in toddlerhood predicted high levels of social withdrawal in early childhood. However, this relation was moderated by attention bias. The BI-withdrawal association was only evident for children who displayed an attention bias toward threat. The data provide further support for models associating attention with socioemotional development and the later emergence of clinical anxiety.     

The development of abstract syntax: Evidence from structural priming and the lexical boost

Structural priming paradigms have been influential in shaping theories of adult sentence processing and theories of syntactic development. However, until recently there have been few attempts to provide an integrated account that explains both adult and developmental data. The aim of the present paper was to begin the process of integration by taking a developmental approach to structural priming. Using a dialog comprehension-to-production paradigm, we primed participants (3–4 year olds, 5–6 year olds and adults) with double object datives (Wendy gave Bob a dog) and prepositional datives (Wendy gave a dog to Bob). Half the participants heard the same verb in prime and target (e.g. gave–gave) and half heard a different verb (e.g. sent–gave). The results revealed substantial differences in the magnitude of priming across development. First, there was a small but significant abstract structural priming effect across all age groups, but this effect was larger in younger children than in older children and adults. Second, adding verb overlap between prime and target prompted a large, significant increase in the priming effect in adults (a lexical boost), a small, marginally significant increase in the older children and no increase in the youngest children. The results support the idea that abstract syntactic knowledge can develop independently of verb-specific frames. They also support the idea that different mechanisms may be needed to explain abstract structural priming and lexical priming, as predicted by the implicit learning account (Bock, K., & Griffin, Z. M. (2000). The persistence of structural priming: Transient activation or implicit learning? Journal of Experimental Psychology – General, 129(2), 177–192). Finally, the results illustrate the value of an integrative developmental approach to both theories of adult sentence processing and theories of syntax acquisition.     

Approach-withdrawal and the role of the striatum in the temperament of behavioral inhibition

Behavioral inhibition is a temperament characterized in infancy and early childhood by a tendency to withdraw from novel or unfamiliar stimuli. Children exhibiting this disposition, relative to children with other dispositions, are more socially reticent, less likely to initiate interaction with peers, and more likely to develop anxiety over time. Until recently, a dominant model attributed this disposition to reductions in the threshold for engaging the circuitry supporting fear learning, particularly the amygdala. Recent work, however, also has implicated striatal circuitry and other regions that constitute components of a presumed reward system. A series of studies found that behaviorally inhibited adolescents display heightened activation of striatal structures to cues indicating an opportunity to receive reward. This article reviews evidence implicating dual roles for fear and reward circuitry in the expression of behavioral inhibition.     

Flexible attention deployment in threatening contexts: An instructed fear conditioning study

Factors leading humans to shift attention away from danger cues remain poorly understood. Two laboratory experiments reported here show that context interacts with learning experiences to shape attention avoidance of mild danger cues. The first experiment exposed 18 participants to contextual threat of electric shock. Attention allocation to mild danger cues was then assessed with the dot-probe task. Results showed that contextual threat caused subjects to avert attention from danger cues. In the second experiment, 36 participants were conditioned to the same contextual threat used in Experiment 1. These subjects then were randomly assigned to either an experimental group, trained to shift attention toward danger cues, or a placebo group exposed to the same stimuli without the training component. As in Experiment 1, contextual threat again caused attention allocation away from danger in the control group. However, this did not occur in the experimental group. These experiments show that acute contextual threat and learning experiences interact to shape the deployment of attention away from danger cues. (PsycINFO Database Record (c) 2012 APA, all rights reserved).