Name: assessment of audio-tactile sensory substitution training in participants with profound deafness using the event-related potential technique
Uploaded: 2022-09-07T13:40:00
Description: Watch this Scientific Journal Video about Assessment of Audio-Tactile Sensory Substitution Training in Participants with Profound Deafness Using the Event-Related Potential Technique at JoVE.com

We thank all the participants and their families, as well as the institutions that made this work possible, in particular, Asociaci&#243;n de Sordos de Jalisco, Asociaci&#243;n Deportiva, Cultural y Recreativa de Silentes de Jalisco, Educaci&#243;n Incluyente, A.C., and Preparatoria No. 7. We also thank Sandra M&#225;rquez for her contribution to this project. This work was funded by GRANT SEP-CONACYT-221809, GRANT SEP-PRODEP 511-6/2020-8586-UDG-PTC-1594, and the Neuroscience Institute (Universidad de Guadalajara, Mexico).

The study was reviewed and approved by the Neuroscience Institute&#39;s Ethics Committee (ET062010-88, Universidad de Guadalajara), ensuring all procedures were conducted in accordance with the Declaration of Helsinki. All participants agreed to participate voluntarily and gave written informed consent (when underaged, parents signed consent forms).
1. Experimental design
<ol>
	<li>Stimulus preparation
	<ol>
		<li>Search in Creative Commons licensed sound databases to select...

<ol>
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J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Components+in+the+P300:+Don't+forget+the+Novelty+P3.">Components in the P300: Don't forget the Novelty P3.</a> Psychophysiology. 57 (7), 13371 (2020).</li><li>Polich, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=P300+clinical+utility+and+control+of+variability.">P300 clinical utility and control of variability.</a> Journal of Clinical Neurophysiology. 15 (1), 14-33 (1998).</li><li>Polich, J., Criado, J. 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D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Decision+making,+the+P3,+and+the+locus+coeruleus--norepinephrine+system.">Decision making, the P3, and the locus coeruleus--norepinephrine system.</a> Psychological Bulletin. 131 (4), 510 (2005).</li><li>Luck, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> An Introduction to the Event-Related Potential Technique. , (2014).</li><li>Kappenman, E. S., Luck, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Best+practices+for+event-related+potential+research+in+clinical+populations.">Best practices for event-related potential research in clinical populations.</a> Biological Psychiatry: Cognitive Neuroscience and Neuroimaging. 1 (2), 110-115 (2016).</li><li>Rac-Lubashevsky, R., Kessler, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Revisiting+the+relationship+between+the+P3b+and+working+memory+updating.">Revisiting the relationship between the P3b and working memory updating.</a> Biological Psychology. 148, 107769 (2019).</li><li>Twomey, D. M., Murphy, P. R., Kelly, S. P., O'Connell, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+classic+P300+encodes+a+build-to-threshold+decision+variable.">The classic P300 encodes a build-to-threshold decision variable.</a> European Journal of Neuroscience. 42 (1), 1636-1643 (2015).</li><li>Boudewyn, M. A., Luck, S. J., Farrens, J. L., Kappenman, E. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+many+trials+does+it+take+to+get+a+significant+ERP+effect?+It+depends.">How many trials does it take to get a significant ERP effect? It depends.</a> Psychophysiology. 55 (6), 13049 (2018).</li><li>Cohen, J., Polich, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+number+of+trials+needed+for+P300.">On the number of trials needed for P300.</a> International Journal ofPsychophysiology. 25 (3), 249-255 (1997).</li><li>Duncan, C. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Event-related+potentials+in+clinical+research:+guidelines+for+eliciting,+recording,+and+quantifying+mismatch+negativity,+P300,+and+N400.">Event-related potentials in clinical research: guidelines for eliciting, recording, and quantifying mismatch negativity, P300, and N400.</a> Clinical Neurophysiology. 120 (11), 1883-1908 (2009).</li><li>Thigpen, N. N., Kappenman, E. S., Keil, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessing+the+internal+consistency+of+the+event-related+potential:+An+example+analysis.">Assessing the internal consistency of the event-related potential: An example analysis.</a> Psychophysiology. 54 (1), 123-138 (2017).</li><li>Huffmeijer, R., Bakermans-Kranenburg, M. J., Alink, L. R., Van IJzendoorn, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reliability+of+event-related+potentials:+the+influence+of+number+of+trials+and+electrodes.">Reliability of event-related potentials: the influence of number of trials and electrodes.</a> Physiology &amp; Behavior. 130, 13-22 (2014).</li><li>Rietdijk, W. J., Franken, I. H., Thurik, A. 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Using ERP tools, we designed a protocol to observe and evaluate the gradual development of vibrotactile discrimination skills for distinguishing vibrotactile representations of different pure tones. Our prior work has demonstrated that vibrotactile stimulation is a viable alternative sound perception method for profoundly deaf individuals. However, because of the complexity of natural sounds compared to pure tones, the potential for language sound discrimination warrants a separate exploration.
<p class="jove_content...

Early profound deafness is a sensory deficit that strongly impacts oral language acquisition and the perception of environmental sounds that play an essential role in navigating everyday life for those with normal hearing. A preserved and functional auditory sensory pathway allows us to hear footsteps when someone is approaching out of visual range, react to oncoming traffic, ambulance sirens, and security alarms, and respond to our own name when someone needs our attention. Audition is, therefore, a vital sense for speech, communication, cognitive development, and timely interaction with the environment, including the perception of potential threats in one&#39;s surroundings. For decades, the viability of audio-tactile substitution as an alternative sound perception method with the potential to complement and facilitate language development in severely hearing-impaired individuals has been explored with limited results1,2,3. Sensory substitution aims to provide users with environmental information through a human sensory channel different from the one normally used; it has been demonstrated to be possible across different sensory systems4,5. Specifically, audio-tactile sensory substitution is achieved when skin mechanoreceptors can transduce the physical energy of soundwaves that compose auditory information into neuronal excitation patterns that can be perceived and integrated with the somatosensory pathways and higher order somatosensory cortical areas6.
Several studies have demonstrated that profoundly deaf individuals can distinguish musical timbre solely through vibrotactile perception7 and discriminate between same-sex speakers using spectral cues of complex vibrotactile stimuli8. More recent findings have shown that deaf individuals concretely benefitted from a brief, well-structured audio-tactile perception training program, as they significantly improved their ability to discriminate between different pure-tone frequencies9 and between pure-tones with different temporal duration10. These experiments used event-related potentials (ERPs), graph connectivity methods, and quantitative electroencephalogram (EEG) measurements to depict and analyze functional brain mechanisms. However, the neural activity associated with the discrimination of complex environmental sounds has not been examined prior to this paper.
ERPs have proven useful for studying time-locked processes, with incredible time resolution in the order of milliseconds, while performing behavioral tasks that involve attention allocation, working memory, and response selection11. As described by Luck, Woodman, and Vogel12, ERPs are intrinsically multidimensional processing measures and are therefore well suited to separately measure the subcomponents of cognition. In an ERP experiment, the continuous ERP waveform elicited by the presentation of a stimulus can be used to directly observe neural activity that is interposed between the stimulus and the behavioral response. Other advantages of the technique, such as its cost-effectiveness and non-invasive nature, make it a perfect fit to study the precise time course of cognitive processes in clinical populations. Furthermore, ERP tools applied in a repeated-measures design, in which patients&#39; electrical brain activity is recorded more than once to study changes in electrical activity after a training program or intervention, provide further insight into neural changes over time.
The P3 component, being the most extensively researched cognitive potential13, is currently recognized to respond to all kinds of stimuli, most apparently to stimuli of low probability, or of high intensity or significance, or ones that require some behavioral or cognitive response14. This component has also proven extremely useful in evaluating general cognitive efficiency in clinical models15,16. A clear advantage of assessing changes in the P3 waveform is that it is an easily observable neural response because of its greater amplitude compared to other smaller components; it has a characteristic centroparietal topographical distribution and is also relatively easy to elicit using the appropriate experimental design17,18,19.
In this context, the aim of this study is to explore the learning-related electrophysiological changes in patients with profound deafness after training for a short period in vibrotactile sound discrimination. In addition, ERP tools are applied to depict the functional brain dynamic underlying the temporary engagement of the cognitive resources demanded by the task.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Audacity</td>
			<td>Audacity team</td>
			<td>audacityteam.org</td>
			<td>Free, open source, cross-platform audio editing software</td>
		</tr>
		<tr>
			<td>Audiometer</td>
			<td>Resonance</td>
			<td>r17a</td>
			<td></td>
		</tr>
		<tr>
			<td>EEG analysis Software</td>
			<td>Neuronic&#160;, S.A.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>EEG recording Software</td>
			<td>Neuronic&#160;, S.A.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Electro-Cap&#160;</td>
			<td>Electro-cap International, Inc.</td>
			<td>E1-M</td>
			<td>Cap with 19 active electrodes, adjustable straps and chest harness.&#160;</td>
		</tr>
		<tr>
			<td>Electro-gel</td>
			<td>Electro-cap International, Inc.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>External computer speakers</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Freesound&#160;</td>
			<td>Music technology group</td>
			<td>freesound.org</td>
			<td>Database of Creative Commons Licensed sounds</td>
		</tr>
		<tr>
			<td>Hook and loop fastner</td>
			<td>Velcro</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>IBM SPSS (Statistical Package for th Social Sciences)</td>
			<td>IBM</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Individual electrodes&#160;</td>
			<td>Cadwell</td>
			<td></td>
			<td>Gold Cup, 60 in</td>
		</tr>
		<tr>
			<td>MEDICID-5</td>
			<td>Neuronic, S.A.</td>
			<td></td>
			<td>EEG recording equipment (includes amplifier and computer).</td>
		</tr>
		<tr>
			<td>Nuprep</td>
			<td>Weaver and company</td>
			<td></td>
			<td>ECG &#38; EEG abrasive skin prepping gel</td>
		</tr>
		<tr>
			<td>Portable computer with touch screen</td>
			<td>Dell</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>SEVITAC-D</td>
			<td>Centro Camac, Argentina. Patented by Luis Campos (2002).</td>
			<td>http://sevitac-d.com.ar/</td>
			<td>Portable stimulator system is worn on the index-finger tip and it consists of a tiny flexible plastic membrane with a 78.5 mm2 surface area that vibrates in response to sound pressure waves via analog transmission. It has a sound frequency range from 10 Hz to 10 kHz.&#160;</td>
		</tr>
		<tr>
			<td>Stimulus presentation Software Mindtracer</td>
			<td>Neuronics, S.A.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Stimulation computer monitor and keyboard</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Tablet computer</td>
			<td>Lenovo</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Ten20 Conductive Neurodiagnostic Electrode paste</td>
			<td>weaver and company</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

assessment of audio-tactile sensory substitution training in participants with profound deafness using the event-related potential technique

This paper examines the application of electroencephalogram-based methods to assess the effects of audio-tactile substitution training in young, profoundly deaf (PD) participants, with the aim of analyzing the neural mechanisms associated with vibrotactile complex sound discrimination. Electrical brain activity reflects dynamic neural changes, and the temporal precision of event-related potentials (ERPs) has proven to be key in studying time-locked processes while performing behavioral tasks that involve attention and working memory. 
The current protocol was designed to study electrophysiological activity in PD subjects while they performed a continuous performance task (CPT) using complex-sound stimuli, consisting of five different animal sounds delivered through a portable stimulator system worn on the right index finger. As a repeated-measures design, electroencephalogram (EEG) recordings in standard conditions were performed before and after a brief training program (five 1 h sessions over 15 days), followed by offline artifact correction and epoch averaging, to obtain individual and grand-mean waveforms. Behavioral results show a significant improvement in discrimination and a more robust P3-like centroparietal positive waveform for the target stimuli after training. In this protocol, ERPs contribute to the further understanding of learning-related neural changes in PD subjects associated with audio-tactile discrimination of complex sounds.

To illustrate how the effect of the audio-tactile sensory substitution discrimination training in PD individuals can be assessed by evaluating changes in P3 in a group of 17 PD individuals (mean age = 18.5 years; SD = 7.2 years; eight females and 11 males), we created several figures to portray the ERP waveforms. The results shown in the ERP plots reveal changes in a P3-like centroparietal positive waveform which is more robust for the target stimuli after training. In the pre-training condition, ERPs suggest that the T ...

Watch this Scientific Journal Video about Assessment of Audio-Tactile Sensory Substitution Training in Participants with Profound Deafness Using the Event-Related Potential Technique at JoVE.com

Assessment of Audio-Tactile Sensory Substitution Training in Participants with Profound Deafness Using the Event-Related Potential Technique

This protocol is designed to explore underlying learning-related electrophysiological changes in subjects with profound deafness after a short training period in audio-tactile sensory substitution by applying the event-related potential technique.

This paper examines the application of electroencephalogram-based methods to assess the effects of audio-tactile substitution training in young, ...

Our protocol demonstrates how ERPs can be applied to explore learning-related neural changes in subjects with profound deafness after a short training period in vibrotactile discrimination of complex natural sounds. The main advantage of the ERP technique is that it allows the study of the precise temporal dynamics of electrical brain activity that underlies cognitive processing during audio-tactile sensory substitution. The implications of this technique could extend towards speech production therapy because audio-tactile sensory feedback could definitely facilitate early oral language development in patients with severe auditory deficits.The current method contributes to the global search for alternatives to treat the specific sensory deficits and provides insights into a more in-depth understanding of the neural basis of sensory transduction. Visual demonstration of this protocol is critical to guarantee replication because so far, the experimentally employed vibrotactile simulation all have distinct approaches in methodology and instrumentation. Demonstrating the procedure will be Geisa, Assistant Professor, Ricardo, master student, Eduardo, student research assistant, and Deborah, MSL interpreter and student research assistant from our lab.Recruit potential participants with profound bilateral sensorineural hearing loss diagnosis and collect demographic data including age, sex, hand preference, and educational history. Conduct semi-structured clinical interviews to screen participants for personal or family history to deafness clinical history. Conduct audiological tests using an audiometer to confirm the severity of hearing loss.In a sound attenuated room, sit directly in front of the participant and properly place headphones on them. Instruct the participants to raise their dominant hand to signal whenever they can hear the tone being presented through the headphones. Ranging from 20 decibels to 110 decibels intensity levels, present a pure tone at six octaves in the ascending order, 250, 500, 1, 000, 2, 000, 4, 000 and 8, 000 hertz, starting with the left ear and repeating for the right ear.Calculate the patient's pure tone average by averaging the hearing thresholds at 500, 1, 000, 2, 000, and 4, 000 hertz for each ear. To prepare the participant, verify that the participant have come to the recording session with clean and dry hair, having not used any hair products that affect electrode impedance. Ask the participant to sit in a comfortable position approximately 60 centimeters away from the stimulus screen and use the tablet device to play the MSL video clip with the preparation steps.Clean the areas where reference and EOG electrodes will be placed. First, wipe the skin with an alcohol swab and then apply EEG abrasive prepping gel gently with a cotton swab to exfoliate dead skin cells on the surface. Fill the electrode gold cup with conductive electrode paste and place an electrode on each reference site.Repeat the steps to place at least one vertical EOG at the outer canthus and one horizontal EOG at the infraocular orbital ridge to monitor oculomotor activity. Hold the single electrodes in place with a piece of one micropore tape. Ask the participants to hold their arms straight horizontally and then fit the body harness tightly but comfortably around the chest under the armpits with the snaps in the middle of the chest.Use a measuring tape to check the participant's head circumference to ensure you use the proper cap size. Place the EEG commercial electro cap with 19 silver chloride electrodes topographically arranged according to the international 10-20 system. Align the front midline electrode with the nose and then measure the distance from the nasion to the inion so that the central midline electrode falls precisely in the middle.Button the adjustable straps on the sides of the cap to the body harness so that the electro cap is firmly tightened. Place the gel-filled blunt needle syringe inside the electrode, circle the needle to remove hair, and then gently abrade the scalp region under the electrode before applying the conductive gel. Don't apply too much gel to avoid electrical bridging with neighboring electrode sites.Then allow the EEG conductive gel to dry at room temperature. Then calibrate the EEG system. Then connect the electro cap to the amplifier set at a bandpass of 0.05 to 30 hertz, a 60 hertz notch filter, and a 200 hertz sampling rate equal to a five millisecond sampling period.Check that the impedance is below five kiloohm in all electrode sites and check on the monitor that all channels are smoothly registering the electrical signals. Then to run the experimental task, position the participant in front of the computer monitor and place the keyboard at a comfortable distance. Connect the cable of the portable stimulator device to the computer system speakers outlet and set the speaker volume to the maximum intensity level.Adjust the portable stimulator system on the participant's right index fingertip and test. Using the tablet device, play the experiment instructions and execute a practice trial to familiarize the subject. Repeat the MSL instructions and verify comprehension.Remind the participant to respond to the dog bark stimulus by pressing the left control key with their left index finger only upon target stimulus detection and to withhold the response when any of the other four animal sounds are perceived. Start recording the EEG signal and click on the communication icon in the interface before starting the CPT task to check that the event synchronization between the cognitive stimulation computer and the EEG recording computer is working properly. Upon clicking, the event synchronized pulses appear at the bottom of the EEG recording screen.Run the experimental task and carefully observe the participant and monitor alertness, response execution, and excessive movement or blinking. Pause and allow the participant a short break in the middle of the experiment to allow them to blink, relax, and move around if needed. Then finish running the experiment.For pre-processing EEG raw signal, define and select epochs of 1, 100 milliseconds in the continuous EEG data without additional digital filters using stimulus onset as the initial time instant and including 100 millisecond pre-stimulus used for baseline correction. During artifact rejection, exclude epochs of data on all channels when the voltage in a given recording epoch exceeds 100 microvolts on any channel, also reject artifacts by visual inspection. Then select an equal number of artifact-free epochs for each stimulus in both the pre and post-training conditions.Do this for each EEG record. Click on the Operations menu and select the EEG window averaging option to average individual ERPs. First, select the independent average option to average target trials only.Then select the other four non-target stimuli and click on the average together option to average. Repeat these steps for pre-training and post-training conditions. Open any individual EP average, then go to the Operations menu and select Grand Mean Averaging option.Select the participants'individual averages to be included in the group average. Choose all pre-training target averages from the dropdown list, then click the Average button, type the desired filename and press the Return key to save. For ERP visualization and analyses, select the Operations menu to see the list of saved grand means.Then click on the group averages that you wish to plot. Next, click the Montage button to select the channels you want to plot. Go to the Tools menu, then click on Visualize Options to select each waveform's color and line width.Then click on the Signal menu, check the DC correction box, type in the desired baseline stimulus interval, then press the Return key. Carefully inspect the plotted grand mean waveforms to identify the components of interest and their corresponding time windows. The pre-training grand averages and post-training grand averages portrayed the main results of this investigation evaluating changes in P3 in a group of 17 profoundly deaf individuals.The ERP waveforms were modified when plotted using a lowpass digital filter at five hertz. The ERP plots revealed changes in a P3-like central parietal positive waveform which was more robust for the target stimuli after training. In the pre-training condition, ERPs suggested that the target and non-target conditions were not as clearly distinguishable as in the post-training condition.The most crucial step is to properly instruct the profoundly deaf participants and to adequately select the artifact-free EEG epochs for each condition before window averaging. Quantitative EEG and functional connectivity could be used to further analyze and interpret the data to describe the neurofunctional changes related to an alternative sensory stimulation training program.

Research

JoVE Journal

Neuroscience

High Density Event-related Potential  Data Acquisition in Cognitive Neuroscience

Functional magnetic resonance imaging (fMRI) is currently the standard method of evaluating brain function in the field of Cognitive Neuroscience, in part ...

Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy

When considering human neuroimaging data, an appreciation of signal variability represents a fundamental innovation in the way we think about brain ...

Assessment of Vascular Regeneration in the CNS Using the Mouse Retina

The rodent retina is perhaps the most accessible mammalian system in which to investigate neurovascular interplay within the central nervous system (CNS). ...

Somatosensory Event-related Potentials from Orofacial Skin Stretch Stimulation

Cortical processing associated with orofacial somatosensory function in speech has received limited experimental attention due to the difficulty of ...

Olfactory Behaviors Assayed by Computer Tracking Of Drosophila in a Four-quadrant Olfactometer

Olfactory Behaviors Assayed by Computer Tracking Of Drosophila in a Four-quadrant Olfactometer

A key challenge in neurobiology is to understand how neural circuits function to guide appropriate animal behaviors. Drosophila melanogaster is an ...

Physiological Preparation of Hair Cells from the Sacculus of the American Bullfrog (Rana catesbeiana)

Physiological Preparation of Hair Cells from the Sacculus of the American Bullfrog Rana catesbeiana

The study of hearing and balance rests upon insights drawn from biophysical studies of model systems. One such model, the sacculus of the American ...

How to Find Effects of Stimulus Processing on Event Related Brain Potentials of Close Others when Hyperscanning Partners

The partners of each pair must be able to pass the McGill Friendship Questionnaire without communicating. Each partner is then seated in front of a screen ...

The Power of Interstimulus Interval for the Assessment of Temporal Processing in Rodents

Temporal processing deficits have been implicated as a potential elemental dimension of higher-level cognitive processes, commonly observed in ...

Stimulus-specific Cortical Visual Evoked Potential Morphological Patterns

This paper presents a methodology for the recording and analysis of cortical visual evoked potentials (CVEPs) in response to various visual stimuli using ...