Papers for the month of November 2014

Wright, A., Troxel, W., Ferrell, R., Flory, J., Manuck, S.

"OXTR polymorphism predicts social relationships through its effects on social temperament"
SCAN, online before print:n/a

Mouse over here for a brief summary or click to open article in a new tab.We show for the first time that OXTR variation plays a significant role not only in the promotion of social affiliative behavior, but also in the creation of social environments. OXTR variation associates with two temperament constructs, negative affectivity and inhibited sociality, which in turn predict levels of individuals’ social support and social network characteristics.

Ashok Litwin-Kumar

"Formation and maintenance of neuronal assemblies through synaptic plasticity"
Nature Communications, 5:5319

Mouse over here for a brief summary or click to open article in a new tab.Our paper presents a large-scale cortical network model with realistic synaptic plasticity rules coupled with homeostatic mechanisms that supports the formation of neuronal assemblies that reflect previously experienced stimuli. Further, reverberation of past evoked states in spontaneous spiking activity stabilizes, rather than erases, this learned architecture. Spontaneous and evoked spiking activity contains a signature of learned assembly structures, leading to testable predictions about the effect of recent sensory experience on spike train statistics.

Vladimir L. Cherkassky, Augusto Buchweitz, Timothy A. Keller, Tom Mitchell

"Identifying Autism from Neural Representations of Social Interactions: Neurocognitive Markers of Autism"
PLoS ONE, 9(12):e1-22

Mouse over here for a brief summary or click to open article in a new tab.This study determined how the neural representations and meanings of social concepts (such as to insult) are altered in autism. A second goal was to determine whether these alterations can serve as neurocognitive markers of autism. The approach is based on previous advances in fMRI analysis methods that permit (a) the identification of a concept, such as the thought of a physical object, from its fMRI pattern [1], and (b) the ability to assess the semantic content of a concept from its fMRI pattern [2, 3]. These factor analysis and machine learning methods were applied to the fMRI activation patterns of 17 adults with high-functioning autism and matched controls, scanned while thinking about 16 social interactions. One prominent neural representation factor that emerged (manifested mainly in posterior midline regions) was related to self-representation, but this factor was present only for the control participants, and was near-absent in the autism group. Moreover, machine learning algorithms classified individuals as autistic or control with 97% accuracy from their fMRI neurocognitive markers.

Strum, J., Nguyen, T.

"Development of intrinsic connectivity in the central nucleus of the mouse inferior colliculus."
The Journal of Neuroscience, 34:15032

Mouse over here for a brief summary or click to open article in a new tab.The inferior colliculus (IC) in the mammalian midbrain is the major subcortical auditory integration center but its synaptic organization is poorly understood. In this study we used laser-scanning photostimulation with caged glutamate to provide the first characterization of the spatial distribution, strength, and refinement of local synaptic connections in the IC of developing and young adult mice.

Leila Wehbe, Brian Murphy, Partha Talukdar, Alona Fyshe, Aaditya Ramdas

"Simultaneously uncovering the patterns of brain regions involved in different story reading subprocesses"
PLOS ONE, 9(11):e112575

Mouse over here for a brief summary or click to open article in a new tab.This paper uses fMRI to reveal how different regions in the brain are processing different types of information when reading a real story in a naturalistic setting. The results include a brain map of the regions which our model suggests are responsible for processing visual, semantic, syntactic and narrative information.

Murphy, M.C. and Kim, S.G.

"Neuronal and Physiological Correlation to Hemodynamic Resting-State Fluctuations in Health and Disease"
Brain Connectivity, 4:727-740

Mouse over here for a brief summary or click to open article in a new tab.This work explored the degree with which hemodynamic connectivity is associated with neuronal, metabolic, and vascular connectivity measures. In summary, we found that measures of node-to-node hemodynamic connectivity are highly correlated with like measures of neuronal connectivity, such that hemodynamic connectivity as measured by blood oxygenation measurements (like fMRI) is a valuable surrogate for the underlying neuronal connectivity.