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Toward A Multimodal Computer-Aided Diagnostic Tool For Alzheimer’S Disease Conversion, Danilo Pena, Jessika Suescun, Mya Schiess, Timothy M. Ellmore, Luca Giancardo, Alzheimer’S Disease Neuroimaging Initiative Jan 2022

Toward A Multimodal Computer-Aided Diagnostic Tool For Alzheimer’S Disease Conversion, Danilo Pena, Jessika Suescun, Mya Schiess, Timothy M. Ellmore, Luca Giancardo, Alzheimer’S Disease Neuroimaging Initiative

Publications and Research

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder. It is one of the leading sources of morbidity and mortality in the aging population AD cardinal symptoms include memory and executive function impairment that profoundly alters a patient’s ability to perform activities of daily living. People with mild cognitive impairment (MCI) exhibit many of the early clinical symptoms of patients with AD and have a high chance of converting to AD in their lifetime. Diagnostic criteria rely on clinical assessment and brain magnetic resonance imaging (MRI). Many groups are working to help automate this process to improve the clinical workflow. Current …


Inter-Subject Correlation While Listening To Minimalist Music: A Study Of Electrophysiological And Behavioral Responses To Steve Reich’S Piano Phase, Tysen Dauer, Duc T. Nguyen, Nick Gang, Jacek P. Dmochowski, Jonathan Berger, Blair Kaneshiro Dec 2021

Inter-Subject Correlation While Listening To Minimalist Music: A Study Of Electrophysiological And Behavioral Responses To Steve Reich’S Piano Phase, Tysen Dauer, Duc T. Nguyen, Nick Gang, Jacek P. Dmochowski, Jonathan Berger, Blair Kaneshiro

Publications and Research

Musical minimalism utilizes the temporal manipulation of restricted collections of rhythmic, melodic, and/or harmonic materials. One example, Steve Reich’s Piano Phase, offers listeners readily audible formal structure with unpredictable events at the local level. For example, pattern recurrences may generate strong expectations which are violated by small temporal and pitch deviations. A hyper-detailed listening strategy prompted by these minute deviations stands in contrast to the type of listening engagement typically cultivated around functional tonal Western music. Recent research has suggested that the inter-subject correlation (ISC) of electroencephalographic (EEG) responses to natural audio-visual stimuli objectively indexes a state of “engagement,” demonstrating …


Acute Effect Of High‑Definition And Conventional Tdcs On Exercise Performance And Psychophysiological Responses In Endurance Athletes: A Randomized Controlled Trial, Daniel Gomes Da Silva Machado, Marom Bikson, Abhishek Datta, Egas Caparelli‑Dáquer, Gozde Unal, Abrahão F. Baptista, Edilson Serpeloni Cyrino, Li Min Li, Edgard Morya, Alexandre Moreira, Alexandre Hideki Okano Jul 2021

Acute Effect Of High‑Definition And Conventional Tdcs On Exercise Performance And Psychophysiological Responses In Endurance Athletes: A Randomized Controlled Trial, Daniel Gomes Da Silva Machado, Marom Bikson, Abhishek Datta, Egas Caparelli‑Dáquer, Gozde Unal, Abrahão F. Baptista, Edilson Serpeloni Cyrino, Li Min Li, Edgard Morya, Alexandre Moreira, Alexandre Hideki Okano

Publications and Research

Transcranial direct current stimulation (tDCS) has been used aiming to boost exercise performance and inconsistent findings have been reported. One possible explanation is related to the limitations of the so-called “conventional” tDCS, which uses large rectangular electrodes, resulting in a diffuse electric field. A new tDCS technique called high-definition tDCS (HD-tDCS) has been recently developed. HD-tDCS uses small ring electrodes and produces improved focality and greater magnitude of its aftereffects. This study tested whether HD-tDCS would improve exercise performance to a greater extent than conventional tDCS. Twelve endurance athletes (29.4 ± 7.3 years; 60.15 ± 5.09 ml kg− 1 min− …


Monolingual And Bilingual Language Networks In Healthy Subjects Using Functional Mri And Graph Theory, Qiongge Li, Luca Pasquini, Gino Del Ferraro, Madeleine Gene, Kyung K. Peck, Hernán A. Makse, Andrei I. Holodny May 2021

Monolingual And Bilingual Language Networks In Healthy Subjects Using Functional Mri And Graph Theory, Qiongge Li, Luca Pasquini, Gino Del Ferraro, Madeleine Gene, Kyung K. Peck, Hernán A. Makse, Andrei I. Holodny

Publications and Research

Bilingualism requires control of multiple language systems, and may lead to architectural differences in language networks obtained from clinical fMRI tasks. Emerging connectivity metrics such as k-core may capture these differences, highlighting crucial network components based on resiliency. We investigated the influence of bilingualism on clinical fMRI language tasks and characterized bilingual networks using connectivity metrics to provide a patient care benchmark. Sixteen right-handed subjects (mean age 42-years; nine males) without neurological history were included: eight native English-speaking monolinguals and eight native Spanish-speaking (L1) bilinguals with acquired English (L2). All subjects underwent fMRI with gold-standard clinical language tasks. Starting from …


Semester Schedule For Cognitive And Behavioral Neuroscience, Megan V. Caldwell Apr 2021

Semester Schedule For Cognitive And Behavioral Neuroscience, Megan V. Caldwell

Open Educational Resources

This course schedule has been created for an asynchronous 15-week, 4 credit Cognitive and Behavioral Neuroscience course. It is a comprehensive schedule including a week-by-week breakdown of lecture topics, reading material, assignments, and exam schedule. The course covers topics related to cognition and neuroscience including the action potential, neurotransmitters, cell gradients, sensation (vision, hearing, and pain/somatosensation), neuroplasticity, memory, and movement systems. The schedule is intended to be accompanied by a syllabus.


Network-Level Mechanisms Underlying Effects Of Transcranial Direct Current Stimulation (Tdcs) On Visuomotor Learning, Pejman Sehatpour, Clément Dondé, Matthew J. Hoptman, Johanna Kreither, Devin Adair, Elisa Dias, Blair Vail, Stephanie Rohrig, Gail Silipo, Javier Lopez-Calderon, Antigona Martinez, Daniel C. Javitt Dec 2020

Network-Level Mechanisms Underlying Effects Of Transcranial Direct Current Stimulation (Tdcs) On Visuomotor Learning, Pejman Sehatpour, Clément Dondé, Matthew J. Hoptman, Johanna Kreither, Devin Adair, Elisa Dias, Blair Vail, Stephanie Rohrig, Gail Silipo, Javier Lopez-Calderon, Antigona Martinez, Daniel C. Javitt

Publications and Research

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation approach in which low level currents are administered over the scalp to influence underlying brain function. Prevailing theories of tDCS focus on modulation of excitation-inhibition balance at the local stimulation location. However, network level effects are reported as well, and appear to depend upon differential underlying mechanisms. Here, we evaluated potential network-level effects of tDCS during the Serial Reaction Time Task (SRTT) using convergent EEG- and fMRI-based connectivity approaches. Motor learning manifested as a significant (p <.0001) shift from slow to fast responses and corresponded to a significant increase in beta-coherence (p <.0001) and fMRI connectivity (p <.01) particularly within the visual-motor pathway. Differential patterns of tDCS effect were observed within different parametric task versions, consistent with network models. Overall, these findings demonstrate objective physiological effects of tDCS at the network level that result in effective behavioral modulation when tDCS parameters are matched to network-level requirements of the underlying task.


Multimodal Computational Modeling Of Visual Object Recognition Deficits But Intact Repetition Priming In Schizophrenia, Pejman Sehatpour, Anahita Bassir Nia, Devin Adair, Zhishun Wang, Heloise M. Debaun, Gail Silipo, Antigona Martinez, Daniel C. Javitt Nov 2020

Multimodal Computational Modeling Of Visual Object Recognition Deficits But Intact Repetition Priming In Schizophrenia, Pejman Sehatpour, Anahita Bassir Nia, Devin Adair, Zhishun Wang, Heloise M. Debaun, Gail Silipo, Antigona Martinez, Daniel C. Javitt

Publications and Research

The term perceptual closure refers to the neural processes responsible for “filling-in” missing information in the visual image under highly adverse viewing conditions such as fog or camouflage. Here we used a closure task that required the participants to identify barely recognizable fragmented line-drawings of common objects. Patients with schizophrenia have been shown to perform poorly on this task. Following priming, controls and importantly patients can complete the line-drawings at greater levels of fragmentation behaviorally, suggesting an improvement in their ability to performthe task. Closure phenomena have been shown to involve a distributed network of cortical regions, notably the lateral …


Olfaction Modulates Inter-Subject Correlation Of Neural Responses, Paul Deguzman, Anshul Jain, Matthias H. Tabert, Lucas C. Parra Jul 2020

Olfaction Modulates Inter-Subject Correlation Of Neural Responses, Paul Deguzman, Anshul Jain, Matthias H. Tabert, Lucas C. Parra

Publications and Research

Odors can be powerful stimulants. It is well-established that odors provide strong cues for recall of locations, people and events. The effects of specific scents on other cognitive functions are less well-established. We hypothesized that scents with different odor qualities will have a different effect on attention. To assess attention, we used Inter-Subject Correlation of the EEG because this metric is strongly modulated by attentional engagement with natural audiovisual stimuli.We predicted that scents known to be “energizing” would increase Inter-Subject Correlation during watching of videos as compared to “calming” scents. In a first experiment, we confirmed this for eucalyptol and …


Two Nights Of Recovery Sleep Restores Hippocampal Connectivity But Not Episodic Memory After Total Sleep Deprivation, Ya Chai, Zhuo Fang, Fan Nils Yang, Sihua Xu, Yao Deng, Andrew Raine, Jieqiong Wang, Meichen Yu, Mathias Basner, Namni Goel, Junghoon J. Kim, David A. Wolk, John A. Detre, David F. Dinges, Hengyi Rao May 2020

Two Nights Of Recovery Sleep Restores Hippocampal Connectivity But Not Episodic Memory After Total Sleep Deprivation, Ya Chai, Zhuo Fang, Fan Nils Yang, Sihua Xu, Yao Deng, Andrew Raine, Jieqiong Wang, Meichen Yu, Mathias Basner, Namni Goel, Junghoon J. Kim, David A. Wolk, John A. Detre, David F. Dinges, Hengyi Rao

Publications and Research

Sleep deprivation significantly impairs a range of cognitive and brain function, particularly episodic memory and the underlying hippocampal function. However, it remains controversial whether one or two nights of recovery sleep following sleep deprivation fully restores brain and cognitive function. In this study, we used functional magnetic resonance imaging (fMRI) and examined the effects of two consecutive nights (20-hour time-in-bed) of recovery sleep on resting-state hippocampal connectivity and episodic memory deficits following one night of total sleep deprivation (TSD) in 39 healthy adults in a controlled in-laboratory protocol. TSD significantly reduced memory performance in a scene recognition task, impaired hippocampal …


Barrels Xxxii Meeting Report: Whiskers In The Windy City, Giuseppe Cataldo, Chia-Chien Chen, Alicia C. Barrientos, Joshua C. Brumberg Jan 2020

Barrels Xxxii Meeting Report: Whiskers In The Windy City, Giuseppe Cataldo, Chia-Chien Chen, Alicia C. Barrientos, Joshua C. Brumberg

Publications and Research

The 32nd Annual Barrels meeting was hosted at the Northwestern University Feinberg School of Medicine in Chicago, Illinois on October 17th and 18th, 2019. The annual meeting brings together researchers who utilize the rodent whisker-to-barrel system as a means to understand cortical function and development. This year’s meeting focused on social behaviors, development and cerebellar functions within the barrel system and beyond.


Visual Modulation Of Resting State Α Oscillations, Kelly Webster, Tony Ro Dec 2019

Visual Modulation Of Resting State Α Oscillations, Kelly Webster, Tony Ro

Publications and Research

Once thought to simply reflect passive cortical idling, recent studies have demonstrated that α oscillations play a causal role in cognition and perception. However, whether and how cognitive or sensory processes modulate various components of the α rhythm is poorly understood. Sensory input and resting states were manipulated in human subjects while electroencephalography (EEG) activity was recorded in three conditions: eyes-open fixating on a visual stimulus, eyes-open without visual input (darkness), and eyes-closed without visual input (darkness). We show that α power and peak frequency increase when visual input is reduced compared to the eyes open, fixating condition. These results …


Neural Correlates Of Decision Making Related To Information Security: Self-Control And Moral Potency, Robert West, Emily Budde, Qing Hu Sep 2019

Neural Correlates Of Decision Making Related To Information Security: Self-Control And Moral Potency, Robert West, Emily Budde, Qing Hu

Publications and Research

Security breaches of digital information represent a significant threat to the wellbeing of individuals, corporations, and governments in the digital era. Roughly 50% of breaches of information security result from the actions of individuals inside organizations (i.e., insider threat), and some evidence indicates that common deterrence programs may not lessen the insiders’ intention to violate information security. This had led researchers to investigate contextual and individual difference variables that influence the intention to violate information security policies. The current research builds upon previous studies and explores the relationship between individual differences in self-control and moral potency and the neural correlates …


Alpha Oscillations And Feedback Processing In Visual Cortex For Conscious Perception, Tony Ro Jul 2019

Alpha Oscillations And Feedback Processing In Visual Cortex For Conscious Perception, Tony Ro

Publications and Research

Variability in perception between individuals may be a consequence of different inherent neural processing speeds. To assess whether alpha oscillations systematically reflect a feedback pacing mechanism for cortical processing during visual perception, comparisons were made between alpha oscillations, visual suppression from TMS, visual evoked responses, and metacontrast masking. Peak alpha oscillation frequencies, measured through scalp EEG recordings, significantly correlated with the optimum latencies for visual suppression from TMS of early visual cortex. Individuals with shorter alpha periods (i.e., higher peak alpha frequencies) processed visual information faster than those with longer alpha periods (i.e., lower peak alpha frequencies). Moreover, peak alpha …


Sensory Perception, Adrian Rodriguez-Contreras May 2019

Sensory Perception, Adrian Rodriguez-Contreras

Open Educational Resources

Different types of sensory systems with their functional modalities will be presented. The biological bases for how these functions are generated and modified will then be described. As vision is the principal means of perception, we will focus in this course most on visual processing. Scientific data will be integrated into the lectures, such that students develop critical skills in analyzing data and proposing hypotheses.


Neural And Behavioral Correlates Of Attentional Inhibition Training And Perceptual Discrimination Training In A Visual Flanker Task, Robert D. Melara, Shalini Singh, Denise A. Hien May 2018

Neural And Behavioral Correlates Of Attentional Inhibition Training And Perceptual Discrimination Training In A Visual Flanker Task, Robert D. Melara, Shalini Singh, Denise A. Hien

Publications and Research

Two groups of healthy young adults were exposed to 3 weeks of cognitive training in a modified version of the visual flanker task, one group trained to discriminate the target (discrimination training) and the other group to ignore the flankers (inhibition training). Inhibition training, but not discrimination training, led to significant reductions in both Garner interference, indicating improved selective attention, and in Stroop interference, indicating more efficient resolution of stimulus conflict. The behavioral gains from training were greatest in participants who showed the poorest selective attention at pretest. Electrophysiological recordings revealed that inhibition training increased the magnitude of Rejection Positivity …


Working Memory And Consciousness: The Current State Of Play, Marjan Persuh, Eric Larock, Jacob Berger Mar 2018

Working Memory And Consciousness: The Current State Of Play, Marjan Persuh, Eric Larock, Jacob Berger

Publications and Research

Working memory (WM), an important posit in cognitive science, allows one to temporarily store and manipulate information in the service of ongoing tasks. WM has been traditionally classified as an explicit memory system—that is, as operating on and maintaining only consciously perceived information. Recently, however, several studies have questioned this assumption, purporting to provide evidence for unconscious WM. In this article, we focus on visual working memory (VWM) and critically examine these studies as well as studies of unconscious perception that seem to provide indirect evidence for unconscious WM. Our analysis indicates that current evidence does not support an unconscious …


Depressive Symptoms Are Associated With Cognitive Function In The Elderly With Type 2 Diabetes, Elizabeth Guerrero-Berroa, Ramit Ravona-Springer, James Schmeidler, Anthony Heymann, Laili Soleimani, Mary Sano, Derek Leroith, Rachel Preiss, Ruth Zukran, Jeremy M. Silverman, Michal Schnaider Beeri Jan 2018

Depressive Symptoms Are Associated With Cognitive Function In The Elderly With Type 2 Diabetes, Elizabeth Guerrero-Berroa, Ramit Ravona-Springer, James Schmeidler, Anthony Heymann, Laili Soleimani, Mary Sano, Derek Leroith, Rachel Preiss, Ruth Zukran, Jeremy M. Silverman, Michal Schnaider Beeri

Publications and Research

Background: Type 2 diabetes (T2D) is a metabolic condition associated with poor clinical and cognitive outcomes including vascular disease, depressive symptoms, cognitive impairment, and dementia. In the general elderly population, depression has been consistently identified as a risk factor for cognitive impairment/decline. However, the association between depression and cognitive function in T2D has been understudied.

Objective: We investigated the association between depression and cognitive function in a large sample of cognitively normal elderly with T2D.

Methods: In this cross-sectional study, we examined 738 participants, aged 65–88 years old, enrolled in the Israel Diabetes and Cognitive Decline study. For each …


Language Experience With A Native-Language Phoneme Sequence Modulates The Effects Of Attention On Cortical Sensory Processing, Valerie L. Shafer, Monica Wagner, Jungmee Lee, Francesca Mingino, Colleen O'Brien, Adam Constantine, Mitchell Steinschneider Nov 2017

Language Experience With A Native-Language Phoneme Sequence Modulates The Effects Of Attention On Cortical Sensory Processing, Valerie L. Shafer, Monica Wagner, Jungmee Lee, Francesca Mingino, Colleen O'Brien, Adam Constantine, Mitchell Steinschneider

Publications and Research

Auditory evoked potentials (AEP) reflect spectro-temporal feature changes within the spoken word and are sufficiently reliable to probe deficits in auditory processing. The current research assessed whether attentional modulation would alter the morphology of these AEPs and whether native-language experience with phoneme sequences would influence the effects of attention. Native-English and native-Polish adults listened to nonsense word pairs that contained the phoneme sequence onsets /st/, /sət/, /pət/ that occur in both the Polish and English languages and the phoneme sequence onset /pt/ that occurs in the Polish language, but not the English language. Participants listened to word pairs within two …


Combined Mnemonic Strategy Training And High-Definition Transcranial Direct Current Stimulation For Memory Deficits In Mild Cognitive Impairment, Benjamin M. Hampstead, Krishnankutty Sathian, Marom Bikson, Anthony Y. Stringer Sep 2017

Combined Mnemonic Strategy Training And High-Definition Transcranial Direct Current Stimulation For Memory Deficits In Mild Cognitive Impairment, Benjamin M. Hampstead, Krishnankutty Sathian, Marom Bikson, Anthony Y. Stringer

Publications and Research

Introduction: Memory deficits characterize Alzheimer’s dementia and the clinical precursor stage known as mild cognitive impairment. Nonpharmacologic interventions hold promise for enhancing functioning in these patients, potentially delaying functional impairment that denotes transition to dementia. Previous findings revealed that mnemonic strategy training (MST) enhances long-term retention of trained stimuli and is accompanied by increased blood oxygen level–dependent signal in the lateral frontal and parietal cortices as well as in the hippocampus. The present study was designed to enhance MST generalization, and the range of patients who benefit, via concurrent delivery of transcranial direct current stimulation (tDCS).

Methods: This protocol describes …


Engaging Narratives Evoke Similar Neural Activity And Lead To Similar Time Perception, Samantha S. Cohen, Simon Henin, Lucas C. Parra Jul 2017

Engaging Narratives Evoke Similar Neural Activity And Lead To Similar Time Perception, Samantha S. Cohen, Simon Henin, Lucas C. Parra

Publications and Research

It is said that we lose track of time - that “time flies” - when we are engrossed in a story. How does engagement with the story cause this distorted perception of time, and what are its neural correlates? People commit both time and attentional resources to an engaging stimulus. For narrative videos, attentional engagement can be represented as the level of similarity between the electroencephalographic responses of different viewers. Here we show that this measure of neural engagement predicted the duration of time that viewers were willing to commit to narrative videos. Contrary to popular wisdom, engagement did not …


Label-Free Fluorescence Spectroscopy For Detecting Key Biomolecules In Brain Tissue From A Mouse Model Of Alzheimer’S Disease, Lingyan Shi, Luyao Lu, George Harvey, Thomas Harvey, Adrián Rodríguez-Contreras, Robert R. Alfano Jun 2017

Label-Free Fluorescence Spectroscopy For Detecting Key Biomolecules In Brain Tissue From A Mouse Model Of Alzheimer’S Disease, Lingyan Shi, Luyao Lu, George Harvey, Thomas Harvey, Adrián Rodríguez-Contreras, Robert R. Alfano

Publications and Research

In this study, label-free fluorescence spectroscopy was used for the first time to determine spectral profiles of tryptophan, reduced nicotinamide adenine dinucleotide (NADH), and flavin denine dinucleotide (FAD) in fresh brain samples of a mouse model of Alzheimer’s disease (AD). Our results showed that the emission spectral profile levels of tryptophan and NADH were higher in AD samples than normal samples. The intensity ratio of tryptophan to NADH and the change rate of fluorescence intensity with respect to wavelength also increased in AD brain. These results yield an optical method for detecting early stage of AD by comparing spectral profiles …


The Healthy Brain Network Serial Scanning Initiative: A Resource For Evaluating Inter-Individual Differences And Their Reliabilities Across Scan Conditions And Sessions, David O'Connor, Natan Vega Potler, Meagan Kovacs, Ting Xu, Lei Ai, John Pellman, Tamara Vanderwal, Lucas C. Parra, Samantha Cohen, Satrajit Ghosh, Jasmine Escalera, Natalie Grant-Villegas, Yael Osman, Anastasia Bui, R. Cameron Craddock, Michael P. Milham Jan 2017

The Healthy Brain Network Serial Scanning Initiative: A Resource For Evaluating Inter-Individual Differences And Their Reliabilities Across Scan Conditions And Sessions, David O'Connor, Natan Vega Potler, Meagan Kovacs, Ting Xu, Lei Ai, John Pellman, Tamara Vanderwal, Lucas C. Parra, Samantha Cohen, Satrajit Ghosh, Jasmine Escalera, Natalie Grant-Villegas, Yael Osman, Anastasia Bui, R. Cameron Craddock, Michael P. Milham

Publications and Research

Background: Although typically measured during the resting state, a growing literature is illustrating the ability to map intrinsic connectivity with functional MRI during task and naturalistic viewing conditions. These paradigms are drawing excitement due to their greater tolerability in clinical and developing populations and because they enable a wider range of analyses (e.g., inter-subject correlations). To be clinically useful, the test-retest reliability of connectivity measured during these paradigms needs to be established. This resource provides data for evaluating test-retest reliability for full-brain connectivity patterns detected during each of four scan conditions that differ with respect to level of engagement (rest, …


Error Rate On The Director’S Task Is Influenced By The Need To Take Another’S Perspective But Not The Type Of Perspective, Edward W. Legg, Laure Olivier, Steven Samuel, Robert Lurz, Nicola S. Clayton Jan 2017

Error Rate On The Director’S Task Is Influenced By The Need To Take Another’S Perspective But Not The Type Of Perspective, Edward W. Legg, Laure Olivier, Steven Samuel, Robert Lurz, Nicola S. Clayton

Publications and Research

Adults are prone to responding erroneously to another’s instructions based on what they themselves see and not what the other person sees. Previous studies have indicated that in instruction-following tasks participants make more errors when required to infer another’s perspective than when following a rule. These inference-induced errors may occur because the inference process itself is error-prone or because they are a side effect of the inference process. Crucially, if the inference process is error-prone, then higher error rates should be found when the perspective to be inferred is more complex. Here, we found that participants were no more error …


Rules And Mechanisms For Efficient Two-Stage Learning In Neural Circuits, Tiberiu Teşileanu, Bence Ölveczky, Vijay Balasubramanian Jan 2017

Rules And Mechanisms For Efficient Two-Stage Learning In Neural Circuits, Tiberiu Teşileanu, Bence Ölveczky, Vijay Balasubramanian

Publications and Research

Trial-and-error learning requires evaluating variable actions and reinforcing successful variants. In songbirds, vocal exploration is induced by LMAN, the output of a basal ganglia-related circuit that also contributes a corrective bias to the vocal output. This bias is gradually consolidated in RA, a motor cortex analogue downstream of LMAN. We develop a new model of such two-stage learning. Using stochastic gradient descent, we derive how the activity in ‘tutor’ circuits (e.g., LMAN) should match plasticity mechanisms in ‘student’ circuits (e.g., RA) to achieve efficient learning. We further describe a reinforcement learning framework through which the tutor can build its teaching …


Rapid And Objective Assessment Of Neural Function In Autism Spectrum Disorder Using Transient Visual Evoked Potentials, Paige M. Siper, Vance Zemon, James Gordon, Julia George-Jones, Stacey Lurie, Jessica Zweifach, Teresa Tavassoli, A. Ting Wang, Jesslyn Jamison, Joseph D. Buxbaum, Alexander Kolevzon Oct 2016

Rapid And Objective Assessment Of Neural Function In Autism Spectrum Disorder Using Transient Visual Evoked Potentials, Paige M. Siper, Vance Zemon, James Gordon, Julia George-Jones, Stacey Lurie, Jessica Zweifach, Teresa Tavassoli, A. Ting Wang, Jesslyn Jamison, Joseph D. Buxbaum, Alexander Kolevzon

Publications and Research

Objective There is a critical need to identify biomarkers and objective outcome measures that can be used to understand underlying neural mechanisms in autism spectrum disorder (ASD). Visual evoked potentials (VEPs) offer a noninvasive technique to evaluate the functional integrity of neural mechanisms, specifically visual pathways, while probing for disease pathophysiology.

Methods Transient VEPs (tVEPs) were obtained from 96 unmedicated children, including 37 children with ASD, 36 typically developing (TD) children, and 23 unaffected siblings (SIBS). A conventional contrast-reversing checkerboard condition was compared to a novel short-duration condition, which was developed to enable objective data collection from severely affected populations …


Does Cognitive Impairment Affect Rehabilitation Outcome In Parkinson’S Disease?, Davide Ferrazzoli, Paola Ortelli, Roberto Maestri, Rossana Bera, Nir Giladi, Maria Felice Ghilardi, Gianni Pezzoli, Giusseppe Frazzitta Aug 2016

Does Cognitive Impairment Affect Rehabilitation Outcome In Parkinson’S Disease?, Davide Ferrazzoli, Paola Ortelli, Roberto Maestri, Rossana Bera, Nir Giladi, Maria Felice Ghilardi, Gianni Pezzoli, Giusseppe Frazzitta

Publications and Research

Background: The cognitive status is generally considered as a major determinant of rehabilitation outcome in Parkinson’s disease (PD). No studies about the effect of cognitive impairment on motor rehabilitation outcomes in PD have been performed before.

Objective: This study is aimed to evaluate the impact of cognitive decline on rehabilitation outcomes in patients with PD.

Methods: We retrospectively identified 485 patients with PD hospitalized for a 4-week Multidisciplinary Intensive Rehabilitation Treatment (MIRT) between January 2014 and September 2015. According to Mini Mental State Examination (MMSE), patients were divided into: group 1—normal cognition (score 27–30), group 2—mild cognitive …


A Review On Locomotor Training After Spinal Cord Injury: Reorganization Of Spinal Neuronal Circuits And Recovery Of Motor Function, Andrew C. Smith, Maria Knikou Jan 2016

A Review On Locomotor Training After Spinal Cord Injury: Reorganization Of Spinal Neuronal Circuits And Recovery Of Motor Function, Andrew C. Smith, Maria Knikou

Publications and Research

Locomotor training is a classic rehabilitation approach utilized with the aim of improving sensorimotor function and walking ability in people with spinal cord injury (SCI). Recent studies have provided strong evidence that locomotor training of persons with clinically complete, motor complete, or motor incomplete SCI induces functional reorganization of spinal neuronal networks at multisegmental levels at rest and during assisted stepping. This neuronal reorganization coincides with improvements in motor function and decreased muscle cocontractions. In this review, we will discuss the manner in which spinal neuronal circuits are impaired and the evidence surrounding plasticity of neuronal activity after locomotor training …


Corticospinal And Reciprocal Inhibition Actions On Human Soleus Motoneuron Activity During Standing And Walking, Berthe Hanna-Boutros, Sina Sangari, Louis-Solal Giboin, Mohamed-Mounir El Mendili, Alexandra Lackmy-Vallée, Véronique Marchand-Pauvert, Maria Knikou Feb 2015

Corticospinal And Reciprocal Inhibition Actions On Human Soleus Motoneuron Activity During Standing And Walking, Berthe Hanna-Boutros, Sina Sangari, Louis-Solal Giboin, Mohamed-Mounir El Mendili, Alexandra Lackmy-Vallée, Véronique Marchand-Pauvert, Maria Knikou

Publications and Research

Reciprocal Ia inhibition constitutes a key segmental neuronal pathway for coordination of antagonist muscles. In this study, we investigated the soleus H-reflex and reciprocal inhibition exerted from flexor group Ia afferents on soleus motoneurons during standing and walking in 15 healthy subjects following transcranial magnetic stimulation (TMS). The effects of separate TMS or deep peroneal nerve (DPN) stimulation and the effects of combined (TMS + DPN) stimuli on the soleus H-reflex were assessed during standing and at mid- and late stance phases of walking. Subthreshold TMS induced short-latency facilitation on the soleus H-reflex that was present during standing and at …


A Principle Of Economy Predicts The Functional Architecture Of Grid Cells, Xue-Xin Wei, Jason Prentice, Vijay Balasubramanian Jan 2015

A Principle Of Economy Predicts The Functional Architecture Of Grid Cells, Xue-Xin Wei, Jason Prentice, Vijay Balasubramanian

Publications and Research

Grid cells in the brain respond when an animal occupies a periodic lattice of ‘grid fields’ during navigation. Grids are organized in modules with different periodicity. We propose that the grid system implements a hierarchical code for space that economizes the number of neurons required to encode location with a given resolution across a range equal to the largest period. This theory predicts that (i) grid fields should lie on a triangular lattice, (ii) grid scales should follow a geometric progression, (iii) the ratio between adjacent grid scales should be √e for idealized neurons, and lie between 1.4 and 1.7 …


Focal Cortical Thickness Correlates Of Exceptional Memory Training In Vedic Priests, Giridhar P. Kalamangalam, Timothy M. Ellmore Oct 2014

Focal Cortical Thickness Correlates Of Exceptional Memory Training In Vedic Priests, Giridhar P. Kalamangalam, Timothy M. Ellmore

Publications and Research

The capacity for semantic memory—the ability to acquire and store knowledge of the world—is highly developed in the human brain. In particular, semantic memory assimilated through an auditory route may be a uniquely human capacity. One method of obtaining neurobiological insight into memory mechanisms is through the study of experts. In this work, we study a group of Hindu Vedic priests, whose religious training requires the memorization of vast tracts of scriptural texts through an oral tradition, recalled spontaneously during a lifetime of subsequent spiritual practice. We demonstrate focal increases of cortical thickness in regions of the left prefrontal lobe …