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Olvera, R.

Publications and source records attributed to Olvera, R..

2 recordsLinked to original sources

GO, NO-GO: A SENSITIVE PERIOD FOR DEVELOPING SEX-SPECIFIC VISUALLY-GUIDED PREY PURSUIT-PREDATOR AVOIDANCE TRADE-OFF STRATEGIES

In natural environments, animals face a trade-off between foraging and staying vigilant against predators, a conflict known to shape sensory processing and behavior through natural selection. Even within a species, this trade-off may be resolved differently depending on age, sex, or life history. To identify the neural mechanisms underlying visually-guided pursuit-avoidance trade-offs, we studied how mice responded to a sudden overhead threat while pursuing a moving, prey-like target near the ground. This paradigm let us quantify orienting decisions in adolescent and adult mice of both sexes. We found that adolescence is a key period when male and female mice begin to diverge in how they resolve this conflict. Manipulating the value of the pursued target during adolescence versus adulthood revealed that adolescence is also a sensitive period for shaping adult escape-to-shelter versus continue to approach target behavior. Notably, hunting experience gained specifically during adolescence caused males, but not females, to shift strategy: experienced adolescent males tended to uniquely shift towards a "no-go" (stay-near-Prey) strategy. All the other groups instead favored an active "go" strategy, repeatedly shifting between approaching target and running to shelter. All mice showed this oscillation between approaching target and escaping to a shelter to some degree, but hunting experience during adolescence most significantly shifted this balance between approach and escape for males.

neuroscience↗

Do Candidate Genes Affect the Brain’s White Matter Microstructure? Large-Scale Evaluation of 6,165 Diffusion MRI Scans

AbstractSusceptibility genes for psychiatric and neurological disorders - including APOE, BDNF, CLU,CNTNAP2, COMT, DISC1, DTNBP1, ErbB4, HFE, NRG1, NTKR3, and ZNF804A - have been reported to affect white matter (WM) microstructure in the healthy human brain, as assessed through diffusion tensor imaging (DTI). However, effects of single nucleotide polymorphisms (SNPs) in these genes explain only a small fraction of the overall variance and are challenging to detect reliably in single cohort studies. To date, few studies have evaluated the reproducibility of these results. As part of the ENIGMA-DTI consortium, we pooled regional fractional anisotropy (FA) measures for 6,165 subjects (CEU ancestry N=4,458) from 11 cohorts worldwide to evaluate effects of 15 candidate SNPs by examining their associations with WM microstructure. Additive association tests were conducted for each SNP. We used several meta-analytic and mega-analytic designs, and we evaluated regions of interest at multiple granularity levels. The ENIGMA-DTI protocol was able to detect single-cohort findings as originally reported. Even so, in this very large sample, no significant associations remained after multiple-testing correction for the 15 SNPs investigated. Suggestive associations (1.3x10-4 < p < 0.05, uncorrected) were found for BDNF, COMT, and ZNF804A in specific tracts. Meta-and mega-analyses revealed similar findings. Regardless of the approach, the previously reported candidate SNPs did not show significant associations with WM microstructure in this largest genetic study of DTI to date; the negative findings are likely not due to insufficient power. Genome-wide studies, involving large-scale meta-analyses, may help to discover SNPs robustly influencing WM microstructure.

neuroscience↗