Linking brain-wide multivoxel activation patterns to behaviour: Examples from language and math

A key goal of cognitive neuroscience is to find simple and direct connections between brain and behaviour. However, fMRI analysis typically involves choices between many possible options, with each choice potentially biasing any brain-behaviour correlations that emerge. Standard methods of fMRI analysis assess each voxel individually, but then face the problem of selection bias when combining those voxels into a region-of-interest, or ROI. Multivariate pattern-based fMRI analysis methods use classifiers to analyse multiple voxels together, but can also introduce selection bias via data-reduction steps as feature selection of voxels, pre-selecting activated regions, or principal components analysis. We show here that strong brain-behaviour links can be revealed without any voxel selection or data reduction, using just plain linear regression as a classifier applied to the whole brain at once, i.e. treating each entire brain volume as a single multi-voxel pattern. The brain-behaviour correlations emerged despite the fact that the classifier was not provided with any information at all about subjects\u27 behaviour, but instead was given only the neural data and its condition-labels. Surprisingly, more powerful classifiers such as a linear SVM and regularised logistic regression produce very similar results. We discuss some possible reasons why the very simple brain-wide linear regression model is able to find correlations with behaviour that are as strong as those obtained on the one hand from a specific ROI and on the other hand from more complex classifiers. In a manner which is unencumbered by arbitrary choices, our approach offers a method for investigating connections between brain and behaviour which is simple, rigorous and direct. © 2010 Elsevier Inc

Perception of American English /r/ and /U by Mandarin speakers: Influences of phonetic identification and category goodness

Abstract: This study examined Mandarin speakers' perception of American English /r/and ill. Eighteen /ra/ and ila'tokens were used that varied in F2 and F3 onset frequencies. Stimuli were identified as the lu/. /ml or /I/ of Mandarin, and were rated for goodness. The similarity of pairs of stimuli was also evaluated. Multi-dimensional scaling (MDS) analyses of similarit) ratings revealed that perception differed substantially from American speakers listening to the same stimuli, indicating the use of native-language representations in the perception of a non-native language. Young infants are able to discriminate phonemic contrasts of both their native language and non-native languages. With continued linguistic experience, sensitivity to non-native contrasts weakens, while sensitivity to native language contrasts is enhanced (1). Language-specific experience not only influences the perceptual organization at the boundaries between speech categories, but within categories as well The current study addressed the non-native perception of American English ir/ and ill by Mandarin speakers. The ill in American English is acoustically and phonetically similar to that of Mandarin. In contrast, ir/ is not a phoneme in Mandarin. Therefore, Mandarin speakers were expected to rely on representations of phonemes in their native language to perceive this non-native sound. The nature of these representations, and whether perception of /I/ is similar to that of Americans, remained questions for the research to answer, thereby providing an example of the perceptual impact of linguistic experience. METHOD Stimuli were 18 synthetic /ra/ and /la/ tokens from Ameiican English which varied in F2 and F3 onset frequencies in 200-me1 steps. Twenty-one native speakers of Mandarin, students in Taiwan, participated in two sessions. In the first session, the initial phoneme of each token was identified and rated for goodness on a 7-point scale. Pilot work revealed that Mandarin speakers classified the tokens as Mandarin /la/, /ua/, and /ma/, so identification was restricted to these phonemes. In the second session, participants rated the similarity of paired tokens on a 7-point scale. Similarity ratings were submitted to MDS to create a perceptual map where the distance between any two tokens corresponded to perceived similarity. [For additional details about procedures and stimuli, see Iverson and Kuhl(5).] RESULTS AND DISCUSSION Identification performance and goodness ratings (top), as well as MDS solutions (bottom), are summarized in The right panel of 206

Event-Related Potentials to an English/Spanish Syllabic Contrast in Mexican 10–13-Month-Old Infants

We report brain electrophysiological responses from 10- to 13-month-old Mexican infants while listening to native and foreign CV-syllable contrasts differing in Voice Onset Time (VOT). All infants showed normal auditory event-related potential (ERP) components. Our analyses showed ERP evidence that Mexican infants are capable of discriminating their native sounds as well as the acoustically salient (aspiration) foreign contrast. The study showed that experience with native language influences VOT perception in Spanish learning infants. The acoustic salience of aspiration is perceived by both Spanish and English learning infants, but exposure provides additional phonetic status to this native-language feature for English learning infants. The effects of early experience and neural commitment as well as the impact of acoustic salience are further discussed

Brain Responses to Words in 2-Year-Olds with Autism Predict Developmental Outcomes at Age 6

Autism Spectrum Disorder (ASD) is a developmental disability that affects social behavior and language acquisition. ASD exhibits great variability in outcomes, with some individuals remaining nonverbal and others exhibiting average or above average function. Cognitive ability contributes to heterogeneity in autism and serves as a modest predictor of later function. We show that a brain measure (event-related potentials, ERPs) of word processing in children with ASD, assessed at the age of 2 years (N = 24), is a broad and robust predictor of receptive language, cognitive ability, and adaptive behavior at ages 4 and 6 years, regardless of the form of intensive clinical treatment during the intervening years. The predictive strength of this brain measure increases over time, and exceeds the predictive strength of a measure of cognitive ability, used here for comparison. These findings have theoretical implications and may eventually lead to neural measures that allow early prediction of developmental outcomes as well as more individually tailored clinical interventions, with the potential for greater effectiveness in treating children with ASD

Shared heritability and functional enrichment across six solid cancers

Correction: Nature Communications 10 (2019): art. 4386 DOI: 10.1038/s41467-019-12095-8Quantifying the genetic correlation between cancers can provide important insights into the mechanisms driving cancer etiology. Using genome-wide association study summary statistics across six cancer types based on a total of 296,215 cases and 301,319 controls of European ancestry, here we estimate the pair-wise genetic correlations between breast, colorectal, head/neck, lung, ovary and prostate cancer, and between cancers and 38 other diseases. We observed statistically significant genetic correlations between lung and head/neck cancer (r(g) = 0.57, p = 4.6 x 10(-8)), breast and ovarian cancer (r(g) = 0.24, p = 7 x 10(-5)), breast and lung cancer (r(g) = 0.18, p = 1.5 x 10(-6)) and breast and colorectal cancer (r(g) = 0.15, p = 1.1 x 10(-4)). We also found that multiple cancers are genetically correlated with non-cancer traits including smoking, psychiatric diseases and metabolic characteristics. Functional enrichment analysis revealed a significant excess contribution of conserved and regulatory regions to cancer heritability. Our comprehensive analysis of cross-cancer heritability suggests that solid tumors arising across tissues share in part a common germline genetic basis.Peer reviewe