Faculty of Education - Research Publications

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    Differential effects of motor cortical excitability and plasticity in young and old individuals: a Transcranial Magnetic Stimulation (TMS) study
    Bashir, S ; Perez, JM ; Horvath, JC ; Pena-Gomez, C ; Vernet, M ; Capia, A ; Alonso-Alonso, M ; Pascual-Leone, A (FRONTIERS MEDIA SA, 2014-06-10)
    Aging is associated with changes in the motor system that, over time, can lead to functional impairments and contribute negatively to the ability to recover after brain damage. Unfortunately, there are still many questions surrounding the physiological mechanisms underlying these impairments. We examined cortico-spinal excitability and plasticity in a young cohort (age range: 19-31) and an elderly cohort (age range: 47-73) of healthy right-handed individuals using navigated transcranial magnetic stimulation (nTMS). Subjects were evaluated with a combination of physiological [motor evoked potentials (MEPs), motor threshold (MT), intracortical inhibition (ICI), intracortical facilitation (ICF), and silent period (SP)] and behavioral [reaction time (RT), pinch force, 9 hole peg task (HPT)] measures at baseline and following one session of low-frequency (1 Hz) navigated repetitive TMS (rTMS) to the right (non-dominant) hemisphere. In the young cohort, the inhibitory effect of 1 Hz rTMS was significantly in the right hemisphere and a significant facilitatory effect was noted in the unstimulated hemisphere. Conversely, in the elderly cohort, we report only a trend toward a facilitatory effect in the unstimulated hemisphere, suggesting reduced cortical plasticity and interhemispheric communication. To this effect, we show that significant differences in hemispheric cortico-spinal excitability were present in the elderly cohort at baseline, with significantly reduced cortico-spinal excitability in the right hemisphere as compared to the left hemisphere. A correlation analysis revealed no significant relationship between cortical thickness of the selected region of interest (ROI) and MEPs in either young or old subjects prior to and following rTMS. When combined with our preliminary results, further research into this topic could lead to the development of neurophysiological markers pertinent to the diagnosis, prognosis, and treatment of neurological diseases characterized by monohemispheric damage and lateralized motor deficits.
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    A Bridge Too Far - Revisited: Reframing Bruer's Neuroeducation Argument for Modern Science of Learning Practitioners
    Horvath, JC ; Donoghue, GM (FRONTIERS MEDIA SA, 2016-03-16)
    In Education and the Brain: A Bridge Too Far, John Bruer argues that, although current neuroscientific findings must filter through cognitive psychology in order to be applicable to the classroom, with increased knowledge the neuroscience/education bridge can someday be built. Here, we suggest that translation cannot be understood as a single process: rather, we demonstrate that at least four different 'bridges' can conceivably be built between these two fields. Following this, we demonstrate that, far from being a matter of information lack, a prescriptive neuroscience/education bridge (the one most relevant to Bruer's argument) is a practical and philosophical impossibility due to incommensurability between non-adjacent compositional levels-of-organization: a limitation inherent in all sciences. After defining this concept in the context of biology, we apply this concept to the learning sciences and demonstrate why all brain research must be behaviorally translated before prescriptive educational applicability can be elucidated. We conclude by exploring examples of how explicating different forms of translation and adopting a levels-of-organization framework can be used to contextualize and beneficially guide research and practice across all learning sciences.
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    On the Irrelevance of Neuromyths to Teacher Effectiveness: Comparing Neuro-Literacy Levels Amongst Award-Winning and Non-award Winning Teachers
    Horvath, JC ; Donoghue, GM ; Horton, AJ ; Lodge, JM ; Hattie, JAC (FRONTIERS MEDIA SA, 2018-09-11)
    A number of studies have recently demonstrated a high level of belief in 'neuromyths' (fallacious arguments about the brain) amongst trainee and non-award winning educators. The authors of these studies infer this to mean that acceptance of these neuromyths has a negative impact on teaching effectiveness. In this study, we explored this assumption by assessing the prevalence of neuromyth acceptance amongst a group of internationally recognized, award-winning teachers and comparing this to previously published data with trainee and non-award winning teacher populations. Results revealed the acceptance of neuromyths to be nearly identical between these two groups, with the only difference occurring on 2 (out of 15) items. These findings suggest that one cannot make simple, unqualified arguments concerning the relationship between belief in neuromyths and teacher effectiveness. In fact, the idea that neuromyths negatively impact upon teaching might, itself, be a neuromyth.
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    Transcranial direct current stimulation: five important issues we aren't discussing (but probably should be)
    Horvath, JC ; Carter, O ; Forte, JD (FRONTIERS MEDIA SA, 2014)
    Transcranial Direct Current Stimulation (tDCS) is a neuromodulatory device often publicized for its ability to enhance cognitive and behavioral performance. These enhancement claims, however, are predicated upon electrophysiological evidence and descriptions which are far from conclusive. In fact, a review of the literature reveals a number of important experimental and technical issues inherent with this device that are simply not being discussed in any meaningful manner. In this paper, we will consider five of these topics. The first, inter-subject variability, explores the extensive between- and within-group differences found within the tDCS literature and highlights the need to properly examine stimulatory response at the individual level. The second, intra-subject reliability, reviews the lack of data concerning tDCS response reliability over time and emphasizes the importance of this knowledge for appropriate stimulatory application. The third, sham stimulation and blinding, draws attention to the importance (yet relative lack) of proper control and blinding practices in the tDCS literature. The fourth, motor and cognitive interference, highlights the often overlooked body of research that suggests typical behaviors and cognitions undertaken during or following tDCS can impair or abolish the effects of stimulation. Finally, the fifth, electric current influences, underscores several largely ignored variables (such as hair thickness and electrode attachments methods) influential to tDCS electric current density and flow. Through this paper, we hope to increase awareness and start an ongoing dialog of these important issues which speak to the efficacy, reliability, and mechanistic foundations of tDCS.