The N400 component of the event-related brain potential iswidely used in research on language and semantic memory,but the cognitive functions underlying N400 amplitudes arestill unclear and actively debated. Recent simulations with aneural network model of word meaning suggest that N400amplitudes might reflect implicit semantic prediction error.Here, we extend these simulations to sentencecomprehension, using a neural network model of sentenceprocessing to simulate a number of N400 effects obtained inempirical research. In the model, sequentially incoming wordsupdate a representation capturing probabilities of elements ofsentence meaning, not only reflecting the constituentspresented so far, but also the model’s best guess at all featuresof the sentence meaning based on the statistical regularities inthe model’s environment internalized in its connectionweights. Simulating influences of semantic congruity, clozeprobability, a word’s position in the sentence, reversalanomalies, semantic and associative priming, categoricallyrelated incongruities, lexical frequency, repetition, andinteractions between repetition and semantic congruity, wefound that the update of the predictive representation ofsentence meaning consistently patterned with N400amplitudes. These results are in line with the idea that N400amplitudes reflect semantic surprise, defined as the change inthe probability distribution over semantic features in anintegrated representation of meaning occasioned by the arrivalof each successive constituent of a sentence.

As described in the ISP proposal, female sex workers in Tijuana’s Zona Norte are subject to significant social and health disparities which lead to high risk sexual behaviors such as drug use, unprotected sex, and sex with multiple partners. As a result, this population has a high incidence of unintended pregnancy and sexually transmitted infections. Previous studies have shown that contraception is severely under-utilized in this population. While condoms are necessary to prevent sexually transmitted infections and education regarding its use continues to be important, given the high rates of unintended pregnancies it is also valuable for this population to learn about other forms of contraception in order to prevent pregnancy.

Black Beauty, National Velvet, My Friend Flicka, Ann Romney’s Olympic dressage horse Rafalca, infamous race horses such as Barbaro and Seabiscuit, and, of course, My Little Pony. What does a three-ounce plastic figurine vaguely recognizable as a “pony” have in common with 1,200 pounds of flesh-and-blood horse? What stories help us narrate our relationships to these very different types of beings? What is the draw toward such figurative and material instantiations of animality? What explains the fact that there are over 9 million horses in the United States 150 years after the industrial revolution mechanized transportation and labor, rendering our dependence on horsepower a relic of our past? The sensual and emotional glories of mud, sweat, tears, and triumph are all very real aspects of contemporary horse-human partnerships, but there is something more that inhabits this horse-crazy love.