How the brain does face recognition

  This is a beautiful result. IIUC, these neuroscientists use the terminology “face axis” instead of (machine learning terminology) variation along an eigenface vector or feature vector. Scientific American: …using a combination of brain imaging and single-neuron recording in macaques, biologist Doris Tsao and her colleagues at Caltech have finally cracked the neural code for …

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Walter Pitts and Neural Nets

Pitts is one of the least studied geniuses of the early information age. See also Wikipedia, Nautil.us. Cabinet Magazine: There are no biographies of Walter Pitts, and any honest discussion of him resists conventional biography. Pitts was among the original participants in the mid-century cybernetics conferences, though he began his association with that group of …

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74 SNP hits from SSGAC GWAS

The SSGAC discovery of 74 SNP hits on educational attainment (EA) is finally published in Nature. Nature News article. EA was used in order to assemble as large a sample as possible (~300k individuals). Specific cognitive scores are only available for a much smaller number of individuals. But SNPs associated with EA are likely to …

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Genetic ancestry and brain morphology

Population structure — i.e., distribution of gene variants by ancestral group — is reflected in brain morphology, as measured using MRI. Brain morphology measurements can be used to predict ancestry. Strictly speaking, the data only show correlation, not genetic causation, but the most plausible interpretation is that genetic differences are causing morphological differences. One could …

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IQ prediction from structural MRI

These authors use machine learning techniques to build sparse predictors based on grey/white matter volumes of specific regions. Correlations obtained are ~ 0.7 (see figure). I predict that genomic estimators of this kind will be available once ~ 1 million genomes and cognitive scores are available for analysis. See also Myths, Sisyphus and g. MRI-Based …

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The Fourth Law of Behavior Genetics?

I believe the law stated below almost follows from the observation that humans brains are complex machines: hence the DNA blueprint has many components, and variance is spread over these components  :^) However, note the evidence for discrete genetic modules of large effect in other species: Discrete genetic modules can control complex behavior (burrowing behavior in …

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Metabolic costs of human brain development

This paper quantifies the unusually high energetic cost of brain development in humans. Brain energy requirements and body-weight growth rate are anti-correlated in childhood. Given these results it would be surprising if nutritional limitations that prevented individuals from achieving their genetic potential in height didn’t also lead to sub-optimal cognitive development. Nutritional deprivation likely stunts …

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