Previous reports of cognitive functioning in children with the 22q11 Deletion Syndrome have reported marked variability in IQ and achievement subtest scores. Studies have begun to explore neuropsychological function in 22q11 DS however results are inconsistent and the profile incomplete. We assessed 40 children ages 5-12 with 22q11 DS. Consistent with past results, visual-spatial memory was significantly lower than verbal memory. Differentially lowered scores were found only in visual attention, working memory and motor function. Contrary with some past results quantitative, verbal ability, and visual spatial memory scores were within 1 SD from the standardization sample mean. Motor behavior, not typically discussed with regard to 22q11 DS school-age children, may be critical to incorporate in neurocognitive studies of children with 22q11 DS. Implications of these findings are considered with regard to past results.

The 22q11 chromosomal deletion syndrome (22q11 DS) is associated with learning disabilities and a complex neuropsychological profile. Previous findings have suggested that executive attention deficits might underlie other neurocognitive anomalies. We administered the child Attention Network Test (ANT) to 52 children ages 5.0 to 11.5, 32 22q11 DS children (19 girls) and 20 controls (13 girls) and assessed the efficiency of segregated executive, orienting, and alerting networks. We hypothesized that 22q11 DS children have impaired executive network efficiency as compared to control siblings. The internal validity of the child ANT was confirmed for this population. Analysis of variance results showed significant main effects for flanker and cue types and no interaction effect in either 22q11 DS children or control siblings. Compared to control siblings, 22q11 DS children had significantly larger (less efficient) executive network scores, significantly increased errors on only incongruent trials, and a significant correlation between executive network scores and accuracy. The implications of these findings for future neurocognitive studies of 22q11 DS children are considered.The 22q11 deletion syndrome (22q11 DS) results from a meiotic deletion of DNA at the q11.2 site on chromosome 22 and its estimated prevalence is 1:4,000 (du Montcel, Mendizabal, Ayme, Sevy, & Philip, 1996). In over 90% of cases the deletion is not transmitted (Morrow et al., 1995). Congenital anomalies of widely varying severity can be associated with this condition and might include heart defects, immunologic deficits, craniofacial dysmorphologies, and velopharyngeal defects such as overt or submucous cleft palate (e.g., Ryan et al., 1997). Prior to identification of a single associated deletion, different clinical labels were used to indicate a given child's congenital anomalies, including DiGeorge Syndrome (primary immunologic deficit), Velo-Cardio-Facial-Syndrome (VCFS; velopharyngeal, heart, and facial anomalies), and Conotruncal Anomaly Face Syndrome (primary heart defect with facial dysmorphologies). Whereas the physical phenotype is heterogeneous, the neurocognitive profile is far more consistent. Researchers have estimated that 90% to 100% of 22q11 DS children are learning disabled (e.g., Lipson et al., 1991;Shprintzen, Goldberg, Young, & Walford, 1981) and hypotonic, with gross and fine motor dyscoordination, associated expressive language delays, attention impairment, and behavioral anomalies . Frank mental retardation is relatively rare and may be associated with prolonged anoxia during early cardiac failure. Of urgent concern, approximately 25% of 22q11 DS children are estimated to develop early adulthood schizophrenia (Murphy & Owen, 1996; Pulver et al., Copyright © 2004 The neurocognitive performance of 22q11 DS children is notably complex however and visuospatial memory deficits alone are unlikely to fully explain their profiles. In fact when a broader complement of abilities was examined additional areas of deficit were revea...

Innovative problem solving, repeated innovation, learning, and inhibitory control are cognitive abilities commonly regarded as important components of behaviorally flexible species. Animals exhibiting these cognitive abilities may be more likely to adapt to the unique demands of living in novel and rapidly changing environments, such as urbanized landscapes. Raccoons (Procyon lotor) are an abundant, generalist species frequently found in urban habitats, and are capable of innovative problem solving, which makes them an ideal species to assess their behavioral flexibility. We gave 20 captive raccoons a multi-access puzzle box to investigate which behavioral and cognitive mechanisms enable the generation of innovative and flexible behaviors in this species. Over two-thirds of raccoons tested were not only capable of innovative problem solving, but displayed repeated innovation by solving more than one solution on the multi-access puzzle box and demonstrated that they learned multiple solutions to a novel problem. Although we found no relationship between our measure of inhibitory control and a raccoon's ability to exhibit repeated innovations, we did find a positive relationship between the diversity of behaviors that an individual exhibited when interacting with the problem and the number of solution types that they solved. We identified other predictors of problem-solving performance, including neophobia and persistence. Finally, we examine the implications of our results in the context of the cognitive-buffer hypothesis and consider whether the widespread success of an adaptive generalist carnivore could be due in part to having these cognitive and behavioral traits.

With rates of psychiatric illnesses such as depression continuing to rise, additional preclinical models are needed to facilitate translational neuroscience research. In the current study, the raccoon (Procyon lotor) was investigated due to its similarities with primate brains, including comparable proportional neuronal densities, cortical magnification of the forepaw area, and cortical gyrification. Specifically, we report on the cytoarchitectural characteristics of raccoons profiled as high, intermediate, or low solvers in a multiaccess problem-solving task. Isotropic fractionation indicated that high-solvers had significantly more cells in the hippocampus (HC) than the other solving groups; further, a nonsignificant trend suggested that this increase in cell profile density was due to increased nonneuronal (e.g., glial) cells. Group differences were not observed in the cellular density of the somatosensory cortex. Thionin-based staining confirmed the presence of von Economo neurons (VENs) in the frontoinsular cortex, although no impact of solving ability on VEN cell profile density levels was observed. Elongated fusiform cells were quantified in the HC dentate gyrus where high-solvers were observed to have higher levels of this cell type than the other solving groups. In sum, the current findings suggest that varying cytoarchitectural phenotypes contribute to cognitive flexibility. Additional research is necessary to determine the translational value of cytoarchitectural distribution patterns on adaptive behavioral outcomes associated with cognitive performance and mental health.

No abstract

This field experiment examined whether the well-documented benefit of spaced over massed training for humans and other animals generalizes to horses. Twenty-nine randomly selected horses (Equus ferus caballus) repeatedly encountered a novel obstacle-crossing task while under saddle. Horses were randomly assigned to the spaced-training condition (2 min work, 2 min rest, 2 min work, 2 min rest) or the massed-training condition (4 min work, 4 min rest). Total training time per session and total rest per session were held constant. Days between sessions (M = 3) were held as consistent as possible given the constraints of conducting research on a working ranch and safety–threatening weather conditions. During each training session, the same hypothesis-naïve rider shaped horses to cross a novel obstacle. Fifteen of 16 horses in the spaced-training condition reached performance criterion (94% success) while only 5 of 13 horses in the massed-training condition reached performance criterion (39% success). Horses in the spaced-training condition also initiated their first obstacle-crossing faster than horses in the massed-training condition and were faster at completing eight crossings than horses in the massed-training condition. Overall, task acquisition was higher for horses undergoing spaced training despite both groups experiencing the same total work and rest time per session. These findings generalize the learning-performance benefit observed in human spaced practice to horses and offer applied benefit to equine training.

No abstract