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Reader AT, Coppi S, Trifonova VS, Ehrsson HH. No reduction in motor-evoked potential amplitude during the rubber hand illusion. Brain Behav 2023; 13:e3211. [PMID: 37548563 PMCID: PMC10570491 DOI: 10.1002/brb3.3211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 07/03/2023] [Accepted: 07/26/2023] [Indexed: 08/08/2023] Open
Abstract
INTRODUCTION In the rubber hand illusion (RHI), touches are applied to a fake hand at the same time as touches are applied to a participant's real hand that is hidden in a congruent position. Synchronous (but not asynchronous) tactile stimulation of the two hands may induce the sensation that the fake hand is the participant's own. As such, the illusion is commonly used to examine the sense of body ownership. Some studies indicate that in addition to the subjective experience of limb ownership reported by participants, the RHI can also reduce corticospinal excitability (e.g., as reflected in motor-evoked potential [MEP] amplitude) and alter parietal-motor cortical connectivity in passive participants. These findings have been taken to support a link between motor cortical processing and the subjective experience of body ownership. METHODS In this study, we tried to replicate the reduction in MEP amplitude associated with the RHI and uncover the components of the illusion that might explain these changes. As such, we used single-pulse transcranial magnetic stimulation to probe the excitability of the corticospinal motor system as participants experienced the RHI. RESULTS Despite participants reporting the presence of the illusion and showing shifts in perceived real hand position towards the fake limb supporting its elicitation, we did not observe any associated reduction in MEP amplitude. CONCLUSION We conclude that a reduction in MEP amplitude is not a reliable outcome of the RHI and argue that if such effects do occur, they are unlikely to be large or functionally relevant.
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Affiliation(s)
- Arran T. Reader
- Department of PsychologyFaculty of Natural SciencesUniversity of StirlingStirlingUK
- Department of NeuroscienceKarolinska InstitutetStockholmSweden
| | - Sara Coppi
- Department of NeuroscienceKarolinska InstitutetStockholmSweden
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Gogulski J, Ross JM, Talbot A, Cline CC, Donati FL, Munot S, Kim N, Gibbs C, Bastin N, Yang J, Minasi C, Sarkar M, Truong J, Keller CJ. Personalized Repetitive Transcranial Magnetic Stimulation for Depression. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2023; 8:351-360. [PMID: 36792455 DOI: 10.1016/j.bpsc.2022.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 10/20/2022] [Accepted: 10/23/2022] [Indexed: 11/06/2022]
Abstract
Personalized treatments are gaining momentum across all fields of medicine. Precision medicine can be applied to neuromodulatory techniques, in which focused brain stimulation treatments such as repetitive transcranial magnetic stimulation (rTMS) modulate brain circuits and alleviate clinical symptoms. rTMS is well tolerated and clinically effective for treatment-resistant depression and other neuropsychiatric disorders. Despite its wide stimulation parameter space (location, angle, pattern, frequency, and intensity can be adjusted), rTMS is currently applied in a one-size-fits-all manner, potentially contributing to its suboptimal clinical response (∼50%). In this review, we examine components of rTMS that can be optimized to account for interindividual variability in neural function and anatomy. We discuss current treatment options for treatment-resistant depression, the neural mechanisms thought to underlie treatment, targeting strategies, stimulation parameter selection, and adaptive closed-loop treatment. We conclude that a better understanding of the wide and modifiable parameter space of rTMS will greatly improve the clinical outcome.
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Affiliation(s)
- Juha Gogulski
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; HUS Diagnostic Center, Clinical Neurophysiology, Clinical Neurosciences, Helsinki University Hospital and University of Helsinki, Helsinki, Finland
| | - Jessica M Ross
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California
| | - Austin Talbot
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California
| | - Christopher C Cline
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California
| | - Francesco L Donati
- Department of Health Sciences, San Paolo Hospital, University of Milan, Milan, Italy
| | - Saachi Munot
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California
| | - Naryeong Kim
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California
| | - Ciara Gibbs
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Nikita Bastin
- Department of Radiology and Orthopedics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jessica Yang
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California
| | - Christopher Minasi
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California
| | - Manjima Sarkar
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California
| | - Jade Truong
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California
| | - Corey J Keller
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California; Veterans Affairs Palo Alto Healthcare System, and the Sierra Pacific Mental Illness, Research, Education, and Clinical Center (MIRECC), Palo Alto, California.
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Recognition and Processing of Visual Information after Neuronavigated Transcranial Magnetic Stimulation Session. Brain Sci 2022; 12:brainsci12091241. [PMID: 36138979 PMCID: PMC9497193 DOI: 10.3390/brainsci12091241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 09/02/2022] [Accepted: 09/12/2022] [Indexed: 11/27/2022] Open
Abstract
Background: Transcranial magnetic stimulation (TMS) is a method of noninvasive and painless stimulation of the nervous system, which is based on Faraday’s law of electromagnetic induction. Over the past twenty years, the TMS technique has been deployed as a tool for the diagnosis and therapy of neurodegenerative diseases, as well as in the treatment of mental disorders (e.g., depression). Methods: We tested the inhibitory effects of repetitive TMS (rTMS) on reaction times to militarily relevant visual stimuli amidst distractors and on accompanying blood oxygenation level dependent (BOLD) signal functional magnetic resonance imaging (fMRI) in 20 healthy people. rTMS was applied over the visual cortices, V1, on both hemispheres with the inhibitory theta burst paradigm with the intensity of 70% of the active motor threshold fMRI in 20 healthy people. Results: Analysis of the reaction time to visual stimuli after using TMS to the V1 visual cortex revealed an increase in the number of incorrect recognitions, and the reaction time was from 843 to 910 ms. In the subgroup of participants (n = 15), after the stimulation, there were significant reductions of BOLD signal in blood flow within V1 cortices. Conclusions: The studies of reaction times after the rTMS revealed the inhibitory effect of rTMS on the reaction times and recognition performance of significant (military) objects in the visual field.
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McInnes AN, Nguyen AT, Carroll TJ, Lipp OV, Marinovic W. Engagement of the contralateral limb can enhance the facilitation of motor output by loud acoustic stimuli. J Neurophysiol 2022; 127:840-855. [PMID: 35264005 DOI: 10.1152/jn.00235.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
When intense sound is presented during light muscle contraction, inhibition of the corticomotoneuronal pathway is observed. During action preparation, this effect is reversed, with sound resulting in excitation of the corticomotoneuronal pathway. We investigated how combined maintenance of a muscle contraction during preparation for a ballistic action impacts the magnitude of the facilitation of motor output by a loud acoustic stimulus (LAS) - a phenomenon known as the StartReact effect. Participants executed ballistic wrist flexion movements and a LAS was presented simultaneously with the imperative signal in a subset of trials. We examined whether the force level or muscle used to maintain a contraction during preparation for the ballistic response impacted reaction time and/or the force of movements triggered by the LAS. These contractions were sustained either ipsilaterally or contralaterally to the ballistic response. The magnitude of facilitation by the LAS was greatest when low force flexion contractions were maintained in the limb contralateral to the ballistic response during preparation. There was little change in facilitation when contractions recruited the contralateral extensor muscle, or when they were sustained in the same limb that executed the ballistic response. We conclude that a larger network of neurons which may be engaged by a contralateral sustained contraction prior to initiation may be recruited by the LAS, further contributing to the motor output of the response. These findings may be particularly applicable in stroke rehabilitation where engagement of the contralesional side may increase the benefits of a LAS to the functional recovery of movement.
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Affiliation(s)
- Aaron N McInnes
- School of Population Health, Discipline of Psychology, Curtin University, Perth, Australia.,Department of Psychiatry and Behavioral Sciences, University of Minnesota, Minneapolis, MN, United States
| | - An T Nguyen
- School of Population Health, Discipline of Psychology, Curtin University, Perth, Australia
| | - Timothy John Carroll
- School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Ottmar V Lipp
- School of Psychology and Counselling, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Welber Marinovic
- School of Population Health, Discipline of Psychology, Curtin University, Perth, Australia
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Kallioniemi E, Awiszus F, Pitkänen M, Julkunen P. Fast acquisition of resting motor threshold with a stimulus-response curve - Possibility or hazard for transcranial magnetic stimulation applications? Clin Neurophysiol Pract 2022; 7:7-15. [PMID: 35024510 PMCID: PMC8733273 DOI: 10.1016/j.cnp.2021.10.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 09/15/2021] [Accepted: 10/05/2021] [Indexed: 11/24/2022] Open
Abstract
Objective Previous research has suggested that transcranial magnetic stimulation (TMS) related cortical excitability measures could be estimated quickly using stimulus-response curves with short interstimulus intervals (ISIs). Here we evaluated the resting motor threshold (rMT) estimated with these curves. Methods Stimulus-response curves were measured with three ISIs: 1.2-2 s, 2-3 s, and 3-4 s. Each curve was formed with 108 stimuli using stimulation intensities ranging from 0.75 to 1.25 times the rMTguess, which was estimated based on motor evoked potential (MEP) amplitudes of three scout responses. Results The ISI did not affect the rMT estimated from the curves (F = 0.235, p = 0.683) or single-trial MEP amplitudes at the group level (F = 0.90, p = 0.405), but a significant subject by ISI interaction (F = 3.64; p < 0.001) was detected in MEP amplitudes. No trend was observed which ISI was most excitable, as it varied between subjects. Conclusions At the group level, the stimulus-response curves are unaffected by the short ISI. At the individual level, these curves are highly affected by the ISI. Significance Estimating rMT using stimulus-response curves with short ISIs impacts the rMT estimate and should be avoided in clinical and research TMS applications.
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Key Words
- APB, abductor pollicis brevis
- EMG, electromyography
- ISI, interstimulus interval
- Interstimulus interval
- MEP, motor evoked potential
- MRI, magnetic resonance imaging
- MSO, maximum stimulator output
- Motor evoked potential
- Motor threshold
- SI, stimulation intensity
- Stimulus-response curve
- TMS, transcranial magnetic stimulation
- rMT, resting motor threshold
- rMTRR, resting motor threshold estimated with the Rossini-Rothwell method
- rMTestimate, resting motor threshold estimated with stimulus–response curves
- rMTguess, resting motor threshold estimated with prior information and three scout pulses
- rMTthreshold, resting motor threshold estimated with the threshold-hunting method
- rMTtrue, true resting motor threshold in simulations
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Affiliation(s)
- Elisa Kallioniemi
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX, United States
| | - Friedemann Awiszus
- Neuromuscular Research Group at the Department of Orthopaedics, Otto-von-Guericke University, Magdeburg, Germany
| | - Minna Pitkänen
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland
| | - Petro Julkunen
- Department of Applied Physics, University of Eastern Finland, Kuopio, Finland.,Department of Clinical Neurophysiology, Kuopio University Hospital, Kuopio, Finland
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Startling Acoustic Stimulation Has Task-Specific Effects on Intracortical Facilitation and Inhibition at Rest and During Visually Guided Isometric Elbow Flexion in Healthy Individuals. Motor Control 2022; 27:96-111. [DOI: 10.1123/mc.2022-0014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 10/03/2022] [Accepted: 10/03/2022] [Indexed: 11/20/2022]
Abstract
Startling acoustic stimulation (SAS) causes a transient effect on the primary motor cortex (M1) nonreflexively. It reduces the cortical excitability at rest, but not during voluntary contraction. However, the effect of SAS on intracortical activity is not clear. The purpose of this study was to investigate the SAS effect on short-interval intracortical inhibition and intracortical facilitation using transcranial magnetic stimulation (TMS). Eleven healthy individuals performed isometric elbow flexion at 10% of maximum voluntary contraction on the dominant side with a real-time visual target (i.e., M1 preactivation) or at rest. TMS was delivered to the M1 ipsilateral to elbow flexion without or with SAS delivered 90 ms prior to TMS. There were three TMS delivery conditions: (a) single pulse, (b) short-interval intracortical inhibition, and (c) intracortical facilitation. TMS-induced motor-evoked potential (MEP) was compared between predetermined TMS and SAS conditions at rest and during ipsilateral voluntary contraction. We confirmed that SAS decreased the MEP amplitude at rest, but not during M1 preactivation. SAS caused task-specific effects on intracortical excitability. Specifically, SAS increased intracortical facilitation at rest and during voluntary contraction. However, SAS decreased short-interval intracortical inhibition only during M1 preactivation. Collectively, our results suggest that SAS transiently influences the motor cortex excitability, possibly via its activation of higher centers, to achieve a visually guided goal-directed task.
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Jang S, Cho M. Delayed activation of leg somatotopic fibers of an injured corticospinal tract in a patient with cerebral infarction. Neural Regen Res 2022; 17:2551-2552. [PMID: 35535910 PMCID: PMC9120684 DOI: 10.4103/1673-5374.339013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Turi Z, Normann C, Domschke K, Vlachos A. Transcranial Magnetic Stimulation in Psychiatry: Is There a Need for Electric Field Standardization? Front Hum Neurosci 2021; 15:639640. [PMID: 33767616 PMCID: PMC7985083 DOI: 10.3389/fnhum.2021.639640] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 02/16/2021] [Indexed: 01/29/2023] Open
Abstract
Single-pulse and repetitive transcranial magnetic stimulation (rTMS) are used in clinical practice for diagnostic and therapeutic purposes. However, rTMS-based therapies that lead to a significant and sustained reduction in neuropsychiatric symptoms remain scarce. While it is generally accepted that the stimulation frequency plays a crucial role in producing the therapeutic effects of rTMS, less attention has been dedicated to determining the role of the electric field strength. Conventional threshold-based intensity selection approaches, such as the resting motor threshold, produce variable stimulation intensities and electric fields across participants and cortical regions. Insufficient standardization of electric field strength may contribute to the variability of rTMS effects and thus therapeutic success. Computational approaches that can prospectively optimize the electric field and standardize it across patients and cortical targets may overcome some of these limitations. Here, we discuss these approaches and propose that electric field standardization will be instrumental for translational science frameworks (e.g., multiscale modeling and basic science approaches) aimed at deciphering the subcellular, cellular, and network mechanisms of rTMS. Advances in understanding these mechanisms will be important for optimizing rTMS-based therapies in psychiatry.
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Affiliation(s)
- Zsolt Turi
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Claus Normann
- Department of Psychiatry and Psychotherapy, Medical Center—Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Katharina Domschke
- Department of Psychiatry and Psychotherapy, Medical Center—Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Andreas Vlachos
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center Brain Links Brain Tools, University of Freiburg, Freiburg, Germany
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Sivaramakrishnan A, Madhavan S. Stimulus Intensity Affects Variability of Motor Evoked Responses of the Non-Paretic, but Not Paretic Tibialis Anterior Muscle in Stroke. Brain Sci 2020; 10:brainsci10050297. [PMID: 32429115 PMCID: PMC7287783 DOI: 10.3390/brainsci10050297] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/08/2020] [Accepted: 05/13/2020] [Indexed: 11/16/2022] Open
Abstract
Background: Transcranial magnetic stimulus induced motor evoked potentials (MEPs) are quantified either with a single suprathreshold stimulus or using a stimulus response curve. Here, we explored variability in MEPs influenced by different stimulus intensities for the tibialis anterior muscle in stroke. Methods: MEPs for the paretic and non-paretic tibialis anterior (TA) muscle representations were collected from 26 participants with stroke at seven intensities. Variability of MEP parameters was examined with coefficients of variation (CV). Results: CV for the non-paretic TA MEP amplitude and area was significantly lower at 130% and 140% active motor threshold (AMT). CV for the paretic TA MEP amplitude and area did not vary with intensity. CV of MEP latency decreased with higher intensities for both muscles. CV of the silent period decreased with higher intensity for the non-paretic TA, but was in reverse for the paretic TA. Conclusion: We recommend a stimulus intensity of greater than 130% AMT to reduce variability for the non-paretic TA. The stimulus intensity did not affect the MEP variability of the paretic TA. Variability of MEPs is affected by intensity and side tested (paretic and non-paretic), suggesting careful selection of experimental parameters for testing.
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Affiliation(s)
- Anjali Sivaramakrishnan
- Brain Plasticity Lab, Department of Physical Therapy, College of Applied Health Sciences, University of Illinois at Chicago (UIC), Chicago, IL 60612, USA;
- Graduate Program in Rehabilitation Sciences, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Sangeetha Madhavan
- Brain Plasticity Lab, Department of Physical Therapy, College of Applied Health Sciences, University of Illinois at Chicago (UIC), Chicago, IL 60612, USA;
- Correspondence: ; Tel.: +1-312-355-2517; Fax: +1-312-996-4583
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The effects of conditioning startling acoustic stimulation (SAS) on the corticospinal motor system: a SAS-TMS study. Exp Brain Res 2019; 237:1973-1980. [PMID: 31143970 DOI: 10.1007/s00221-019-05569-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 05/27/2019] [Indexed: 12/25/2022]
Abstract
A startling acoustic stimulus (SAS) could cause transient effects on the primary motor cortex and its descending tracts after habituation of reflex responses. In the literature, there is evidence that the effects of SAS depend on the status of M1 excitability and delivery time of SAS. In this study, we aimed to comprehensively investigate the effects of SAS on the excitability of primary motor cortex. Eleven healthy subjects participated in this study. Transcranial magnetic stimulation (TMS) was delivered to the hot spot for left biceps at rest and during isometric right elbow flexion (10, 30, and 60% of their maximum voluntary contraction, MVC). There were three SAS conditions: (1) No SAS; (2) SAS was delivered 50 ms prior to TMS (SAS50); (3) SAS 90 ms prior to TMS (SAS90). For each subject, the induced MEP amplitude was normalized to the largest response at rest with No SAS. Two-way ANOVAs (4 force levels × 3 SAS conditions) with repeated measures were used to determine the differences under different conditions. For the MEP amplitude, there were significant force level effect and FORCE LEVEL × SAS interactions. Specifically, the MEP amplitude increased with force level. Furthermore, post hoc analysis showed that the MEP amplitude reduced during SAS50 and SAS90 compared to No SAS only at rest. Our results provide evidence that a conditioning SAS causes a transient suppression of the corticospinal excitability at rest when it is delivered 50 ms and 90 ms prior to TMS. However, a conditioning SAS has no effect when the corticospinal excitability is already elevated with an external visual target.
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