Portable Intermodal Preferential Looking (IPL): Investigating Language Comprehension in Typically Developing Toddlers and Young Children with Autism
A reliable home-based way to assess the language comprehension of very young typically developing children, as well as those with autism, is described. The method analyzes children's eye gaze while viewing side-by-side images but hearing an audio that matches only one image. Stimuli are designed with young participants in mind.
Eye tracking has long been used to study gaze patterns in typically-developing individuals, but recent technological advancements have made its use with clinical populations, including autism, more feasible. While eye-tracking young children with autism can offer insight into early symptom manifestations, it involves methodological challenges. Suggestions for best practices are provided.
Neuroimaging techniques, such as functional MRI and Diffusion Tensor Imaging have become increasingly useful in characterizing the cognitive and neural deficits in autism. An examination of brain connectivity in autism at a network level along with adaptations for scanning children with developmental disabilities is presented.
Combining Computer Game-Based Behavioural Experiments With High-Density EEG and Infrared Gaze Tracking
1Department of Human Development, Cornell University, 2Social Sciences Division, University of Chicago, 3National Brain Research Centre, Manesar, India
Procedures for recording high-density EEG and gaze data during computer game-based cognitive tasks are described. Using a video game to present cognitive tasks enhances ecological validity without sacrificing experimental control.
1Centre of Excellence in Neuromics, CHUM Research Center and the Department of Medicine, Universite de Montreal, 2Center of Excellence in Neuromics, CHU Sainte Justine and CHUM Notre-Dame Research Centers, Universite de Montreal, 3Department of Medicine, Universite de Montreal
Molecular genetic strategy for finding de novo mutations causing common disorders such as autism and schizophrenia.
TMS: Using the Theta-Burst Protocol to Explore Mechasnism of Plasticity in Individuals with Fragile X Syndrome and Autism
In this article, we examine the effects of Theta-Burst TMS stimulation on cortical plasticity in individuals suffering from Fragile X syndrome and individuals on the autistic spectrum.
Investigating Social Cognition in Infants and Adults Using Dense Array Electroencephalography (dEEG)
Dense array electroencephalography is being used increasingly to study social cognitive functions in infants and adults. Here we present an established methodology that represents a significant improvement on conventional methodologies for studying EEG in infants and adults.
A simple method to record extracellular field potentials in the larval zebrafish forebrain is described. The method provides a robust in vivo read-out of seizure-like activity. This technique can be used with genetically modified zebrafish larvae carrying epilepsy-related genes or seizures evoked by administration of convulsant drugs.
Assessment of Cerebral Lateralization in Children using Functional Transcranial Doppler Ultrasound (fTCD)
Functional transcranial Doppler sonography (fTCD) is a simple and non-invasive ultrasound technique which can be used to assess the lateralization of cognitive functions, especially language, and is suitable for use with children.
1Department of Computing Science, University of Alberta, 2Department of Psychology, University of Illinois, 3Centre for Neuroscience, University of Alberta, 4Department of Psychology, University of Alberta, 5Department of Marketing, Business Economics, and Law, University of Alberta, 6Neuroscience Program, University of Illinois at Urbana-Champaign, 7Beckman Institute, University of Illinois at Urbana-Champaign
This article demonstrates an experimental design in which whole-body animated characters are used in conjunction with functional magnetic resonance imaging (fMRI) to investigate the neural correlates of observing virtual social interactions.
Until recently, expression studies on human brain were limited to quantification of RNA or protein. With the chromatin immunoprecipitation techniques described in this paper, it will be possible to map histone methylation and other epigenetic regulators of gene expression in postmortem brain.
1Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 2Toronto Centre for Phenogenomics, Mount Sinai Hospital, 3Department of Medical Biophysics, University of Toronto, 4Department of Psychology, University of Toronto, 5Department of Psychiatry, University of Toronto
Here we describe a detailed protocol for examination of sociability in mice by using Crawley's sociability and preference for social novelty test. We describe the advantages and possible applications for this procedure, including critical details important for correct interpretation of the results.
A Practical Approach to Genetic Inducible Fate Mapping: A Visual Guide to Mark and Track Cells In Vivo
Genetic Inducible Fate Mapping (GIFM) marks and tracks cells with fine spatial and temporal control in vivo and elucidates how cells from a specific genetic lineage contribute to developing and adult tissues. Demonstrated here are the techniques required to fate map E12.5 mouse embryos for epifluorescent and explant analysis.
Osmotic Avoidance in Caenorhabditis elegans: Synaptic Function of Two Genes, Orthologues of Human NRXN1 and NLGN1, as Candidates for Autism
Neurexins and neuroligins are membrane-neuron adhesion proteins which perform essential roles in synaptic differentiation and transmission. Neuroligin deficient mutants of C. elegans are defective in detecting osmotic strength, but when they also contain a mutation in the gene coding neurexin, they recover the wild type phenotype.
In this article, we examine the methodology and considerations relevant to the combination of TMS and fMRI to examine the effects of brain stimulation on the default network.
Ex utero Electroporation and Whole Hemisphere Explants: A Simple Experimental Method for Studies of Early Cortical Development
This protocol describes an improved explant procedure that involves ex utero electroporation, dissection and culture of entire cerebral hemispheres from the embryonic mouse. The preparation facilitates pharmacological studies and assays of gene function during early cortical development.
We use the patch-clamp technique to measure GABA-activated single-channel currents (GABAA channels, GABAA receptors) and the synaptic and tonic currents they generate in neurons. Activation of the channels decreases neuronal excitability in health and disease 1,2,3,4.
Voice disorders are debilitating in aging and Parkinson disease. The ultrasonic vocalizations of rats, also affected by these conditions, can be used to study these voice disorders, their neural substrates, and the nature of functional recovery with behavioral intervention.
Mosaic Analysis of Gene Function in Postnatal Mouse Brain Development by Using Virus-based Cre Recombination
1Neuroscience Graduate Program, Keck School of Medicine, University of Southern California, 2Zilkha Neurogenetic Institute, University of Southern California, 3Department of Cell and Neurobiology, Neuroscience Graduate Program, Keck School of Medicine, University of Southern California
An in vivo method to test gene function in postnatal brain is described. Recombinant AAVs expressing Cre and/or a fluorescent protein are injected into neonatal mouse brain. Mosaic gene inactivation and sparse neuronal labeling are achieved, allowing rapid analysis of gene function in processes critical to neural circuit development.
Numerous recent studies have identified mutations in synaptic proteins associated with brain pathologies. Primary cultured cortical neurons offer great flexibility in examining the effects of these disease-associated proteins on dendritic spine morphology and motility.
1NICN, Aix Marseille University, 2LNPM, Aix Marseille University, 3ENT Department, Aix Marseille University, 4Gene expression Laboratory, The Salk Institute for Biological Studies, 5Laboratory of Speech and Language, Aix Marseille University, 6Centre d'Investigations Cliniques en Biothérapie, Aix Marseille University
We describe here a method for biopsying olfactory mucosa from rat and human nasal cavities. These biopsies can be used for either identifying molecular anomalies in brain diseases or isolating multipotent adult stem cells that can be utilized for cell transplantation in animal models of brain trauma/disease.
T-maze Forced Alternation and Left-right Discrimination Tasks for Assessing Working and Reference Memory in Mice
1Division of Systems Medical Science, Institute for Comprehensive Medical Science, Fujita Health University, 2Japan Science and Technology Agency, Core Research for Evolutionary Science and Technology (CREST), 3Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, National Institutes of Natural Sciences
This article presents the protocol of T-maze tests using a modified automated apparatus for assessing the learning and memory functions in mice.
We describe a protocol for using bone morphogenetic protein-7 (BMP-7) or Matrigel to selectively induce dendritic growth in primary sympathetic neurons dissociated from the superior cervical ganglia (SCG) of perinatal rats.
Habituation and prepulse inhibition of startle are operational measures of sensory gating. Sensory gating is disrupted in schizophrenia, and some other mental disorders and neurodegenerative diseases. We here describe a standard protocol to assess short-term and long-term habituation as well as prepulse inhibition of acoustic startle responses in rats and mice.
1Center for the Neural Basis of Cognition, 2Department of Psychology, University of Pittsburgh, 3Department of Psychology, Carnegie Mellon University, 4Department of Bioengineering, University of Pittsburgh
We describe a novel approach for simultaneous analysis of brain function and structure using magnetic resonance imaging (MRI). We assess brain structure with high-resolution diffusion-weighted imaging and white-matter fiber tractography. Unlike standard structural MRI, these techniques allow us to directly relate anatomical connectivity to functional properties of brain networks.
How to Measure Cortical Folding from MR Images: a Step-by-Step Tutorial to Compute Local Gyrification Index
1Department of Psychiatry, University of Geneva School of Medicine, 2Signal Processing Laboratory, École Polytechnique Fédérale de Lausanne, 3Department of Radiology, University Hospital Center and University of Lausanne, 4Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital
Measuring gyrification (cortical folding) at any age represents a window into early brain development. Hence, we previously developed an algorithm to measure local gyrification at thousands of points over the hemisphere1. In this paper, we detail the computation of this local gyrification index.