Name: Forfatter Spotlight: Undersøgelse af vokal informationsrepræsentation hos små primater og dens ændring af psykiatriske lidelser ved hjælp af ikke-invasivt EEG
Uploaded: 2024-07-26T14:15:00
Description: Vocal communication plays a crucial role in the social interactions of primates, particularly in survival and social organization. Humans have developed a ...

Dette arbejde blev støttet af Hakubi-projektet fra Kyoto Universitet, Grant-in-Aid for Challenging Research (Pioneering) (No.22K18644), Grant-in-Aid for Scientific Research (C) (No. 22K12745), Grant-in-Aid for Scientific Research (B) (No. 21H02851) og Grant-in-Aid for Scientific Research (A) (No. 19H01039). Vi vil gerne takke Editage (www.editage.jp) for engelsksproget redigering.

Alle forsøg blev godkendt af EHUB's dyreforsøgskomité (nr. 2022-003, 2023-104) og udført i overensstemmelse med vejledningen for pleje og brug af laboratorieprimater udgivet af EHUB. Ni almindelige silkeaber (Callithrix jacchus, seks hanner og tre hunner, 2-12 år gamle, der vejede 330-490 g) blev brugt til forsøget.
1. Dyr
<ol><li>Huse silkeaberne i enkeltbure udstyret med redekasser, træpinde og andre berigelsesanordninger.</li>
	<li>Hold rummene under en 12...

Ikke-invasivt EEG til sammenlignende undersøgelser af vokal opfattelse hos silkeaber

Punkter at bemærke om anæstesi Både ketamin- og xylazinadministration er blevet forsøgt, og selvom disse er smertestillende og derfor velegnede til lange smertefulde opgaver, har silkeaber en tendens til at opleve fald i blodets iltniveauer uden iltindånding44. Kort sagt er alfaxalon nok bedst egnet til smertefri opgaver såsom barbering eller maskefremstilling. Derudover ville inhalationsanæstesi være den bedst egnede til barbering-, som kun tager 10-15 minutter. Isoflu...

Primater bruger artsspecifikke vokaliseringer til at formidle biologisk vigtig information, såsom opkalderens følelsesmæssige tilstand eller hensigt om at opretholde sociale bånd, tilstedeværelsen af rovdyr eller andre farlige situationer. Undersøgelse af de neurale mekanismer, der ligger til grund for opfattelsen af vokalisering hos vokalrige ikke-menneskelige primater, kan give os kritiske ledetråde til bedre at forstå den evolutionære oprindelse af menneskeligt sprog.
Silkeaber er små primater, der er hjemmehørende i Sydamerika. I de senere år er silkeaber i stigende grad blevet brugt som modeldyr sammen med makakaber på grund af deres høje reproduktivitet, brugervenlighed på grund af deres lille størrelse og udviklingen af nyttige transgene teknikker 1,2,3. Ud over deres anvendelighed som sygdomsmodeller er rig vokal kommunikation inden for grupper en anden unik egenskab ved denne art 4,5,6,7. Silkeaber udveksler rutinemæssigt vokale signaler for at kommunikere med usynlige artsfæller i skoven. Ved at undersøge hjerneaktiviteten involveret i vokal opfattelse og produktion hos silkeaber, kan vi bestemme, hvordan de behandler den auditive information af deres egne eller konspecifikke kald i hjernen og identificere, hvilke neurale kredsløb der er involveret. Tidligere undersøgelser har vist neural aktivitet i den primære auditive cortex 8,9,10,11,12 og frontal cortex 13,14 involveret i vokalproduktion hos silkeaber. Desuden blev disse exciterede og undertrykte neuronale responser moduleret af auditive-vokale interaktioner i den primære auditive cortex 8,10. Disse undersøgelser gav detaljerede neurale aktivitetsdata på enkeltneuronniveau ved hjælp af invasive optagelsesmetoder. Talrige undersøgelser har yderligere undersøgt den neurale aktivitet, der er involveret i silkeabens vokalproduktion; vokal opfattelse er dog stadig dårligt forstået15,16.
Adskillige ikke-invasive hjernebilleddannelsesundersøgelser har belyst de neurale mekanismer for vokalbehandling hos silkeaber 17,18,19; Deres høje rumlige opløsning er en fordel, men at holde dyr i vågen tilstand under scanning kræver avancerede teknikker. Men for nylig identificerede Jafari et al. frontotemporale regioner involveret i vokal opfattelse hos vågne silkeaber ved hjælp af funktionel magnetisk resonansbilleddannelse (fMRI)19. Næsten alle eksperimenter til at belyse hjernefunktionerne involveret i vokal opfattelse og produktion hos mennesker er blevet udført ved hjælp af ikke-invasive metoder, såsom hovedbundselektroencefalografi (EEG), magnetoencefalografi (MEG) 20,21 og fMRI 22,23,24. Talrige undersøgelser på mennesker har undersøgt hjerneaktivitet relateret til vokal opfattelse ved hjælp af EEG. De fleste af disse undersøgelser har fokuseret på følelsesmæssig information 25,26,27 og fremtrædende følelser28, hvor resultaterne afslører ændringer i begivenhedsrelaterede potentialer under vokal perception29. Elektrokortikografi (ECoG) og enkeltneuronoptagelser ved hjælp af intrakranielt implanterede elektroder hos mennesker er kun blevet udført i et begrænset antal eksperimenter med patienter, der gennemgår neurokirurgisk behandling 30,31.
Et evolutionært perspektiv, der sammenligner mennesker med aber, er vigtigt, når man skal forstå de unikke neurale mekanismer, der ligger til grund for vokal opfattelse og produktion, der har udviklet sig hos mennesker. For direkte at sammenligne de neurale mekanismer, der er involveret i taleopfattelse og vokalisering hos vokalrige ikke-menneskelige primater, såsom silkeaben, med mennesker, er det vigtigt at sammenligne data mellem de to arter ved hjælp af samme metode. Funktionel MR tillader billeddannelse af hele hjernen og har en høj rumlig opløsning. Det har den fordel, at det registrerer aktivitet vinkelret på kraniet eller i dybe områder, der er vanskelige at registrere med EEG eller MEG. MR-maskinen er dog dyr at installere og vedligeholde, og der er mange begrænsninger for de stimuli, der kan præsenteres på grund af enhedens art. Til sammenligning har EEG, hændelsesrelaterede potentialer (ERP'er) og MEG en høj tidsmæssig opløsning, hvilket gør dem nyttige til at analysere tidsserier vokalbehandling. Især EEG har fordelene ved høj mobilitet og evnen til at blive brugt i en række eksperimentelle omgivelser, relativt lave omkostninger og kravet om kun en enkelt operatør.
Da en stor mængde EEG-data allerede er opnået hos mennesker, er EEG-målemetoder ved hjælp af ikke-invasive paradigmer nødvendige for ikke-menneskelige primater. Vores forskningsgruppe udviklede en unik ikke-invasiv EEG-registreringsmetode ved hjælp af rør32 til makaker og silkeaber. Her rapporterer vi flere nye resultater vedrørende auditiv behandling hos ikke-menneskelige primater 33,34,35,36,37. For at karakterisere hjerneaktivitet som reaktion på artsspecifikke vokaliseringer i silkeaber konstruerede vi et eksperimentelt system til ikke-invasivt at registrere hjerneaktivitet ved hjælp af elektroder placeret på hovedbunden. I dette studie beskriver vi EEG-målemetoden for silkeaber.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
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			<td>Alfaxalone</td>
			<td>Meiji Animal Health</td>
			<td>Alfaxan</td>
			<td></td>
		</tr>
		<tr>
			<td>Amplifier</td>
			<td>Brain Products</td>
			<td>BrainAmp</td>
			<td></td>
		</tr>
		<tr>
			<td>Atropine</td>
			<td>Fuso Pharmaceutical Industries</td>
			<td>Atropine Sulfate Injection</td>
			<td></td>
		</tr>
		<tr>
			<td>Audio editor</td>
			<td>Adobe</td>
			<td>Adobe Audition</td>
			<td></td>
		</tr>
		<tr>
			<td>Data processing software</td>
			<td>MathWorks</td>
			<td>MATLAB</td>
			<td>version R2023a</td>
		</tr>
		<tr>
			<td>Data processing toolbox</td>
			<td>University of California-SanDiego</td>
			<td>EEGLAB</td>
			<td></td>
		</tr>
		<tr>
			<td>Data processing toolbox</td>
			<td>University of California-Davis</td>
			<td>ERPLAB</td>
			<td></td>
		</tr>
		<tr>
			<td>Electric shaver</td>
			<td>Panasonic</td>
			<td>ER803PPA</td>
			<td></td>
		</tr>
		<tr>
			<td>Electrode</td>
			<td>Unique Medical</td>
			<td>UL-3010</td>
			<td>AgCl coated (custom)</td>
		</tr>
		<tr>
			<td>Electrode gel</td>
			<td>Neurospec AG</td>
			<td>V16 SuperVisc</td>
			<td></td>
		</tr>
		<tr>
			<td>Electrode input box</td>
			<td>Brain Products</td>
			<td>EIB64-DUO</td>
			<td>64ch</td>
		</tr>
		<tr>
			<td>Glue</td>
			<td>3M</td>
			<td>Scotch 7005S</td>
			<td></td>
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		<tr>
			<td>Hair removering cream</td>
			<td>Kracie</td>
			<td>epilat for sensitive skin</td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>Bussan Animal Health</td>
			<td>ds isoflurane</td>
			<td></td>
		</tr>
		<tr>
			<td>Liquid gum</td>
			<td>San-ei Yakuhin Boeki</td>
			<td>Arabic Call SS</td>
			<td>Gum arabic+water</td>
		</tr>
		<tr>
			<td>Liquid nutrition</td>
			<td>Nestl&#233; Health Science Company</td>
			<td>Isocal 1.0 Junior</td>
			<td>Polymeric formula</td>
		</tr>
		<tr>
			<td>Maropitant</td>
			<td>Zoetis&#160;</td>
			<td>Cerenia injectable solution</td>
			<td></td>
		</tr>
		<tr>
			<td>Monitor Camera</td>
			<td>Intel</td>
			<td>RealSense LiDAR Camera L515</td>
			<td></td>
		</tr>
		<tr>
			<td>Monkey pellets</td>
			<td>Oriental Yeast</td>
			<td>SPS</td>
			<td></td>
		</tr>
		<tr>
			<td>Primate chair</td>
			<td>Natsume Seisakusho</td>
			<td>Order made</td>
			<td></td>
		</tr>
		<tr>
			<td>Pulse oximeters</td>
			<td>Covident</td>
			<td>Nellcor</td>
			<td>PM10N</td>
		</tr>
		<tr>
			<td>Skin prepping pasta&#160;</td>
			<td>Mammendorfer Institut f&#252;r Physik und Medizin</td>
			<td>NeuPrep</td>
			<td></td>
		</tr>
		<tr>
			<td>Slicon tube</td>
			<td>AsONE</td>
			<td>&#934;4 x 7mm</td>
			<td></td>
		</tr>
		<tr>
			<td>Speaker</td>
			<td>Fostex</td>
			<td>PM0.3</td>
			<td></td>
		</tr>
		<tr>
			<td>Synchronization device</td>
			<td>Brain Vision</td>
			<td>StimTrak</td>
			<td></td>
		</tr>
		<tr>
			<td>Thermoplastic mask</td>
			<td>CIVCO</td>
			<td>MTAPU Type Uniframe Thermoplastic Mask 2.4mm</td>
			<td></td>
		</tr>
	</tbody>
</table>

electroencephalography measurements in awake marmosets listening to conspecific vocalizations 

Vokal kommunikation spiller en afgørende rolle i primaters sociale interaktioner, især i overlevelse og social organisation. Mennesker har udviklet en unik og avanceret vokal kommunikationsstrategi i form af sprog. For at studere udviklingen af menneskeligt sprog er det nødvendigt at undersøge de neurale mekanismer, der ligger til grund for vokalbehandling hos mennesker, samt at forstå, hvordan hjernemekanismer har udviklet sig ved at sammenligne dem med dem hos ikke-menneskelige primater. Heri udviklede vi en metode til ikke-invasivt at måle elektroencefalografi (EEG) af vågne ikke-menneskelige primater. Denne registreringsmetode giver mulighed for langsigtede undersøgelser uden at skade dyrene, og vigtigst af alt giver os mulighed for direkte at sammenligne ikke-menneskelige primat-EEG-data med menneskelige data, hvilket giver indsigt i udviklingen af menneskeligt sprog. I den aktuelle undersøgelse brugte vi hovedbunds-EEG-registreringsmetoden til at undersøge hjerneaktivitet som reaktion på artsspecifikke vokaliseringer hos silkeaber. Denne undersøgelse giver ny indsigt ved at bruge hovedbunds-EEG til at fange udbredte neurale repræsentationer i silkeaber under vokal opfattelse og udfylde huller i eksisterende viden.

Primates use species-specific vocalizations to convey biologically important information, such as the caller&#39;s emotional state or intention to maintain social bonds, the presence of predators, or other dangerous situations. Investigation of the neural mechanisms underlying the perception of vocalization in vocal-rich nonhuman primates may provide us with critical clues to better understand the evolutionary origins of human language.
Common marmosets are small primates native to South America. In recent years, marmosets have been increasingly used as model animals, alongside macaque monkeys, because of their high reproductivity, ease of use owing to their small size, and the development of useful transgenic techniques1,2,3. In addition to their utility as disease models, rich vocal communication within groups is another unique characteristic of this species4,5,6,7. Marmosets routinely exchange vocal signals to communicate with invisible conspecifics in the forest. By examining the brain activity involved in vocal perception and production in marmosets, we can determine how they process the auditory information of their own or conspecific calls in the brain and identify which neural circuits are involved. Previous studies have demonstrated neural activity in the primary auditory cortex8,9,10,11,12 and frontal cortex13,14 involved in vocal production in marmosets. Furthermore, these excited and suppressed neuronal responses were modulated by auditory-vocal interactions in the primary auditory cortex8,10. These studies provided detailed neural activity data at the single-neuron level using invasive recording methods. Numerous studies have further examined the neural activity involved in marmoset vocal production; however, vocal perception remains poorly understood15,16.
Several noninvasive brain imaging studies have elucidated the neural mechanisms of vocal processing in marmosets17,18,19; their high spatial resolution is an advantage, however, keeping animals in the awake state during scanning requires advanced techniques. However, more recently, Jafari et al. identified frontotemporal regions involved in vocal perception in awake marmosets using functional magnetic resonance imaging (fMRI)19. Almost all experiments to elucidate the brain functions involved in vocal perception and production in humans have been conducted using noninvasive methods, such as scalp electroencephalography (EEG), magnetoencephalography (MEG)20,21, and fMRI22,23,24. Numerous studies in humans have investigated brain activity related to vocal perception using EEG. Most of these studies have focused on emotional information25,26,27 and the saliency of emotional words28, with the results revealing changes in event-related potentials during vocal perception29. Electrocorticography (ECoG) and single-neuron recordings using intracranially implanted electrodes in humans have only been conducted in a limited number of experiments in patients undergoing neurosurgical treatment30,31.
An evolutionary perspective comparing humans with monkeys is important when understanding the unique neural mechanisms underlying vocal perception and production that have developed in humans. To directly compare the neural mechanisms involved in speech perception and vocalization in vocal-rich nonhuman primates, such as the marmoset, with humans, it is important to compare data between the two species using the same method. Functional MRI allows whole-brain imaging and has a high spatial resolution. It has the advantage of recording activity perpendicular to the skull or in deep regions that are difficult to record with EEG or MEG. However, the MRI machine is expensive to install and maintain, and there are many restrictions on the stimuli that can be presented due to the nature of the device. In comparison, EEG, event-related potentials (ERPs), and MEG have a high temporal resolution, making them useful for analyzing time-series vocal processing. In particular, EEG has the advantages of high mobility and the ability to be used in a variety of experimental settings, relatively low cost, and the requirement for just a single operator.
Since a large amount of EEG data has already been obtained in humans, EEG measurement methods using non-invasive paradigms are needed for non-human primates. Our research group developed a unique noninvasive EEG recording method using tubes32 for macaques and marmosets. Here, we report several novel findings regarding auditory processing in nonhuman primates33,34,35,36,37. To characterize brain activity in response to species-specific vocalizations in marmosets, we constructed an experimental system to noninvasively record brain activity using electrodes placed on the scalp. In this study, we describe the EEG measurement method for marmosets.

Forfatter Spotlight: Undersøgelse af vokal informationsrepræsentation hos små primater og dens ændring af psykiatriske lidelser ved hjælp af ikke-invasivt EEG

Elektroencefalografimålinger hos vågne silkeaber, der lytter til konspecifikke vokaliseringer 

We would like to know how vocal information is represented in the brain of small primates which are rich in vocal communications. We would like to illustrate how the representation will be altered by psychiatric disorders such as schizophrenia in the future. We compared non-invasive EEGs across four primate species, and found that the latency of auditory cortex to respond to sounds is longer in humans than in other primates.This would have a significant impact on the perception of complex sounds, such as calls and speech sounds. Few experimental methods allow direct comparison of brain activity obtained from human and animals. We hope to quantify the process of human language evolution by direct comparison, or directly comparing data among various animal species using the non-invasive measurement method.We hope to address this challenge with our protocol.

Først plottede vi de gennemsnitlige begivenhedsrelaterede potentialer (ERP'er) for hver auditiv stimulus i silkeaberne (figur 2). Det auditive fremkaldte potentiale (AEP) var fremtrædende i støjtilstanden , hvilket afspejlede den klare begyndelse af stimuli (se figur 1D). For at sammenligne de gennemsnitlige ERP'er mellem opkaldstyper og støjstimuli anvendte vi en envejsanalyse af varians (ANOVA) med stimuli som mellem-forsøgsperson-faktoren i Cz-r...

For at studere sprogets udvikling er det vigtigt at sammenligne hjernemekanismer hos mennesker med dem hos ikke-menneskelige primater. Vi udviklede en metode til ikke-invasivt at måle elektroencefalografi (EEG) hos vågne dyr. Det giver os mulighed for direkte at sammenligne EEG-data mellem mennesker og dyr på lang sigt uden at skade dem.

Vocal communication plays a crucial role in the social interactions of primates, particularly in survival and social organization. Humans have developed a ...

electroencephalography-measurements-awake-marmosets-listening-to

Research

JoVE Journal

Neuroscience

Electroencephalography Measurements in Awake Marmosets Listening to Conspecific Vocalizations 

Vocal communication plays a crucial role in the social interactions of primates, particularly in survival and social organization. Humans have developed a unique and advanced vocal communication strategy in the form of language. To study the evolution of human language, it is necessary to investigate the neural mechanisms underlying vocal processing in humans, as well as to understand how brain mechanisms have evolved by comparing them with those in nonhuman primates. Herein, we developed a method to noninvasively measure the electroencephalography (EEG) of awake nonhuman primates. This recording method allows for long-term studies without harming the animals, and, importantly, allows us to directly compare nonhuman primate EEG data with human data, providing insights into the evolution of human language. In the current study, we used the scalp EEG recording method to investigate brain activity in response to species-specific vocalizations in marmosets. This study provides novel insights by using scalp EEG to capture widespread neural representations in marmosets during vocal perception, filling gaps in existing knowledge.

To study the evolution of language, comparing brain mechanisms in humans with those in nonhuman primates is important. We developed a method to noninvasively measure the electroencephalography (EEG) of awake animals. It allows us to directly compare EEG data between humans and animals for the long term without harming them.

Development and Implementation of Noninvasive EEG Recording Methods for Auditory Processing Studies in Marmosets

After anesthetizing the marmoset, monitor the vitals with a pulse oximeter. If necessary, administer an oxygen air mixture. Maintain the room temperature above 27 degrees Celsius, and wrap a warming cloth around the body of the marmoset to prevent hypothermia.Using an electric shaver, shave the head. Apply hair removal cream for sensitive skin. After five minutes, wipe off the cream with wet gauze.Drill four screw holes into the protruding back portion of the mask to align with the vertical length of the chair. Next place the anesthetized marmoset on the primate chair. Secure the animal on the chair using neck and waist plates.Place the thermoplastic mask plate in hot water to soften it to fit the head of the marmoset. Remove the mask plate from the water and allow it to cool before placing it on the subject's head. After hardening, remove the mask from the marmoset head.Cut out the top of the head and ear parts of the mask to expose the area for the electrode setting. Habituate the marmoset to the chair under awake conditions and reward it for approximately 30 minutes. Connect a 64 channel electrode input box to the amplifier.Arrange the speaker near the amplifier and control the sound level at 65 to 75 decibels to deliver auditory stimuli. Place the camera in front of the subject to monitor their condition during the EEG recording. Then arrange the primate chair in front of the camera.Attach a transfer cage to a small window of the home cage and allow the marmoset to move to the transfer cage. Cover the carrying cage with a cloth and transfer it to the experimental room. Hold the mart using protective gloves and place it on the primate chair.Put the previously prepared mask on the mart's head. Pass the screws attached to the chair through the hole in the mask and fix it using thumb screws. Use the nasion, inion, and ear lobes as anatomical landmarks to determine the location of the electrodes according to the international 10:20 method.Measure the distance between the nasion and inion in the midline with a tape. Define the location of Cz in the middle of the distance. Position the other electrodes with 20%of the inion/nasion length as the electrode spacing.Mark the electrode positions on the scalp using an oil-based dermatograph. Rub the marked area with a thin cotton swab dipped in alcohol to remove dirt and sebum from the scalp. Using a tube cutter, cut a piece of silicon tubing into a length of approximately seven to nine millimeters.Apply adhesive to the edges of the cut tube and adhere it to the scalp. Using a syringe with a non-pointed needle, fill the inside of the tube with EEG gel. Connect the reference electrode to PZ and the ground electrodes to F4 or F3.Insert electrodes into the tube and connect the electrode cable to the input box.Launch the EEG recording application. Adjust the parameters to ensure all electrodes are below five kilo-Ohms and measure the electrode impedance. During head immobilization and between task sessions, administer one to three milliliters of liquid reward using a syringe.Specify the file to be saved on the EEG recording software and press the start recording button. Immediately run the script for stimulus presentation. When the stimulus presentation script execution is completed, press the stop button to end all recordings.Then remove the electrodes and head mask from the marmoset. Capture the animal and place it back in the carrying cage. Record simple and compound calls from marmoset that are not used in subsequent EEG recordings.Extract three species-specific simple and compound calls from the recorded files. Next, create white noise using a function in the programming software and use that as a stimulus. To follow this, use three auditory files of marmoset calls in the experiment.Control the task using a custom script. In each sound stimulus file, the right channel contains the marmoset call or noise data, and the left channel contains the trigger signal for the onset of the stimulus. Send the trigger signal to the EEG system via a synchronization device and record it as event time.The auditory evoked potential was prominent in the noise condition reflecting the clear onset of the stimuli. The time frequency analysis showed that event related spectral power increased at a lower frequency immediately after stimulus onset. The CZ region showed a decrease in gamma range power lasting for one second post stimulus onset in younger subjects.The initial transient responses in the FZ region revealed significant main effects of stimulus, type, and age with no significant interaction. Sustained responses in CZ showed a significant effect of stimulus type, but no effect of age or interaction.