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Gkalitsiou Z, Byrd C. Differences in auditory verbal working memory between adults who do and do not stutter on an N-back task. JOURNAL OF FLUENCY DISORDERS 2023; 77:105998. [PMID: 37531866 DOI: 10.1016/j.jfludis.2023.105998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 07/13/2023] [Accepted: 07/25/2023] [Indexed: 08/04/2023]
Abstract
PURPOSE The purpose of this study was to investigate auditory verbal working memory in adults who do (AWS) and do not (AWNS) stutter using a highly demanding linguistic N-back task. METHODS Fifteen AWS and 15 AWNS matched in age, gender and educational level were asked to hear series of words and respond by pressing a "yes" button if the word they just heard was the same as the word one, two, or three trials back. Words were either phonologically similar (i.e., Phonological Linguistic Condition) or phonologically dissimilar (i.e., Neutral Linguistic Condition). Accuracy and false alarms rates as well as reaction time on correct target trials, missed target trials and false alarms were collected and analyzed. RESULTS Differences were not found between AWS and AWNS in accuracy. Both groups were more accurate and significantly faster in 1- followed by 2- followed by 3-back trials. However, AWS were significantly slower than AWNS in the 2-back level, regardless of linguistic condition. Furthermore, AWS demonstrated more false alarms compared to AWNS. CONCLUSION Results revealed differences in auditory verbal working memory and interference control between AWS and AWNS when processing highly linguistically demanding stimuli.
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Affiliation(s)
- Zoi Gkalitsiou
- The University of Texas at Austin, Department of Speech, Language, and Hearing Sciences, USA.
| | - Courtney Byrd
- The University of Texas at Austin, Department of Speech, Language, and Hearing Sciences, USA; Arthur M. Blank Center for Stuttering Education and Research, Department of Speech, Language, and Hearing Sciences, The University of Texas at Austin, USA
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Bakhtiar M, Eggers K. Exogenous verbal response inhibition in adults who do and do not stutter. JOURNAL OF FLUENCY DISORDERS 2023; 75:105957. [PMID: 36565523 DOI: 10.1016/j.jfludis.2022.105957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 12/06/2022] [Accepted: 12/11/2022] [Indexed: 06/17/2023]
Abstract
INTRODUCTION Behavioral and questionnaire-based studies suggest that children who stutter (CWS) exhibit poorer response inhibition than children who do not stutter (CWNS). However, the behavioral findings in adults who stutter (AWS) are less unequivocal and mainly based on manual response inhibition. Further study is therefore needed, especially given the lack of studies on verbal response inhibition among these groups. METHODS Thirteen AWS and 14 adults who do not stutter (AWNS) participated in a verbal stop signal task (SST) in which they were asked to read aloud six Chinese characters as fast as possible during the go-signal and ignore-signal trials and refrain from naming them during the stop-signal trials. RESULTS The two groups showed a comparable response reaction time in the go-signal and ignore-signal trial conditions. Furthermore, there were no significant differences in terms of the stop-signal reaction time (SSRT) and accuracy. However, a significant positive correlation was found between SSRT and the frequency of stuttering in conversation but not in reading. CONCLUSION Current findings seem to provide additional support that exogenously triggered response inhibition among AWS does not differ from AWNS. The association between stuttering frequency and SSRT seems to suggest that individuals with more severe stuttering in conversational speech have reduced exogenous response inhibition. However, this finding needs to be further explored in future studies using different measures of stuttering severity.
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Affiliation(s)
- Mehdi Bakhtiar
- Unit of Human Communication, Development, and Information Sciences, The University of Hong Kong, Hong Kong Special Administrative Region.
| | - Kurt Eggers
- Department of Rehabilitation Sciences, Ghent University, Ghent, Belgium; Department of Speech-Language Pathology, Thomas More University College, Belgium; Department of Psychology and Speech-Language Pathology, University of Turku, Finland
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G D, B H S, Gajbe U, Singh BR, Sawal A, Balwir T. The Role of Basal Ganglia and Its Neuronal Connections in the Development of Stuttering: A Review Article. Cureus 2022; 14:e28653. [PMID: 36196326 PMCID: PMC9525748 DOI: 10.7759/cureus.28653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 08/31/2022] [Indexed: 11/05/2022] Open
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Assaneo MF, Ripollés P, Tichenor SE, Yaruss JS, Jackson ES. The Relationship Between Auditory-Motor Integration, Interoceptive Awareness, and Self-Reported Stuttering Severity. Front Integr Neurosci 2022; 16:869571. [PMID: 35600224 PMCID: PMC9120354 DOI: 10.3389/fnint.2022.869571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 04/13/2022] [Indexed: 11/13/2022] Open
Abstract
Stuttering is a neurodevelopmental speech disorder associated with motor timing that differs from non-stutterers. While neurodevelopmental disorders impacted by timing are associated with compromised auditory-motor integration and interoception, the interplay between those abilities and stuttering remains unexplored. Here, we studied the relationships between speech auditory-motor synchronization (a proxy for auditory-motor integration), interoceptive awareness, and self-reported stuttering severity using remotely delivered assessments. Results indicate that in general, stutterers and non-stutterers exhibit similar auditory-motor integration and interoceptive abilities. However, while speech auditory-motor synchrony (i.e., integration) and interoceptive awareness were not related, speech synchrony was inversely related to the speaker’s perception of stuttering severity as perceived by others, and interoceptive awareness was inversely related to self-reported stuttering impact. These findings support claims that stuttering is a heterogeneous, multi-faceted disorder such that uncorrelated auditory-motor integration and interoception measurements predicted different aspects of stuttering, suggesting two unrelated sources of timing differences associated with the disorder.
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Affiliation(s)
- M. Florencia Assaneo
- Institute of Neurobiology, National Autonomous University of Mexico, Querétaro, Mexico
- *Correspondence: M. Florencia Assaneo Eric S. Jackson
| | - Pablo Ripollés
- Department of Psychology, New York University, New York, NY, United States
- Music and Audio Research Lab, New York University, New York, NY, United States
- Center for Music, Language and Emotion, New York University, New York, NY, United States
| | - Seth E. Tichenor
- Department of Speech-Language Pathology, Duquesne University, Pittsburgh, PA, United States
| | - J. Scott Yaruss
- Department of Communicative Sciences and Disorders, Michigan State University, East Lansing, MI, United States
| | - Eric S. Jackson
- Department of Communicative Sciences and Disorders, New York University, New York, NY, United States
- *Correspondence: M. Florencia Assaneo Eric S. Jackson
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Neef NE, Korzeczek A, Primaßin A, Wolff von Gudenberg A, Dechent P, Riedel CH, Paulus W, Sommer M. White matter tract strength correlates with therapy outcome in persistent developmental stuttering. Hum Brain Mapp 2022; 43:3357-3374. [PMID: 35415866 PMCID: PMC9248304 DOI: 10.1002/hbm.25853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/22/2022] [Accepted: 03/22/2022] [Indexed: 11/11/2022] Open
Abstract
Persistent stuttering is a prevalent neurodevelopmental speech disorder, which presents with involuntary speech blocks, sound and syllable repetitions, and sound prolongations. Affected individuals often struggle with negative feelings, elevated anxiety, and low self-esteem. Neuroimaging studies frequently link persistent stuttering with cortical alterations and dysfunctional cortico-basal ganglia-thalamocortical loops; dMRI data also point toward connectivity changes of the superior longitudinal fasciculus (SLF) and the frontal aslant tract (FAT). Both tracts are involved in speech and language functions, and the FAT also supports inhibitory control and conflict monitoring. Whether the two tracts are involved in therapy-associated improvements and how they relate to therapeutic outcomes is currently unknown. Here, we analyzed dMRI data of 22 patients who participated in a fluency-shaping program, 18 patients not participating in therapy, and 27 fluent control participants, measured 1 year apart. We used diffusion tractography to segment the SLF and FAT bilaterally and to quantify their microstructural properties before and after a fluency-shaping program. Participants learned to speak with soft articulation, pitch, and voicing during a 2-week on-site boot camp and computer-assisted biofeedback-based daily training for 1 year. Therapy had no impact on the microstructural properties of the two tracts. Yet, after therapy, stuttering severity correlated positively with left SLF fractional anisotropy, whereas relief from the social-emotional burden to stutter correlated negatively with right FAT fractional anisotropy. Thus, posttreatment, speech motor performance relates to the left dorsal stream, while the experience of the adverse impact of stuttering relates to the structure recently associated with conflict monitoring and action inhibition.
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Affiliation(s)
- Nicole E Neef
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Göttingen, Göttingen, Germany.,Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany
| | - Alexandra Korzeczek
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany
| | - Annika Primaßin
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany.,Fachbereich Gesundheit, FH Münster University of Applied Sciences, Münster, Germany
| | | | - Peter Dechent
- Department of Cognitive Neurology, MR Research in Neurosciences, University Medical Center Göttingen, Göttingen, Germany
| | - Christian Heiner Riedel
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Göttingen, Göttingen, Germany
| | - Walter Paulus
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany
| | - Martin Sommer
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany.,Department of Neurology, University Medical Center Göttingen, Göttingen, Germany.,Department of Geriatrics, University Medical Center Göttingen, Göttingen, Germany
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Lescht E, Dickey MW, Stockbridge MD, Ratner NB. Adults Who Stutter Show Diminished Word Fluency, Regardless of Mode. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2022; 65:906-922. [PMID: 35133869 PMCID: PMC9150734 DOI: 10.1044/2021_jslhr-21-00344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 10/03/2021] [Accepted: 11/07/2021] [Indexed: 06/14/2023]
Abstract
PURPOSE Language abilities have long been thought to be weaker in adults who stutter (AWS) compared to adults who do not stutter (AWNS). However, it is unknown whether modality affects language performance by AWS in time pressure situations. This study aimed to examine lexical access and retrieval abilities of AWS in oral and typed modes. METHOD Fifteen AWS and 15 well-matched AWNS completed computer-administered letter fluency tasks. Adults were asked to orally produce words that began with one of two letter targets and type words that began with one of two alternate letters. Conditions were counterbalanced across participants. RESULTS Generalized linear mixed-effects models were evaluated to determine the effects of group (AWS/AWNS), mode (oral/typed), and expressive vocabulary on letter fluency performance. Group predicted letter fluency such that AWS generated fewer items on both the oral and typed letter fluency tasks. Mode did not impact letter fluency results. Expressive Vocabulary Test scores predicted letter fluency similarly in both AWS and AWNS. CONCLUSIONS AWS were not penalized by oral task demands. AWS generated fewer items on the letter fluency tasks regardless of response mode, suggesting that they have weaker lexical access abilities. Furthermore, better expressive vocabulary skills were associated with better letter fluency performance in both groups.
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Affiliation(s)
- Erica Lescht
- Department of Communication Science and Disorders, University of Pittsburgh, PA
| | - Michael Walsh Dickey
- Department of Communication Science and Disorders, University of Pittsburgh, PA
- Geriatric Research Education and Clinical Center, VA Pittsburgh Healthcare System, PA
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Maxfield ND. Cognitive control of action naming in adults who stutter. JOURNAL OF FLUENCY DISORDERS 2021; 70:105841. [PMID: 33667938 PMCID: PMC8390602 DOI: 10.1016/j.jfludis.2021.105841] [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: 08/31/2020] [Revised: 02/22/2021] [Accepted: 02/23/2021] [Indexed: 06/12/2023]
Abstract
PURPOSE Based on previous evidence that cognitive control of lexical selection in object (noun) naming operates differently in adults who stutter (AWS) versus typically-fluent adults (TFA), the aim was to investigate cognitive control of lexical selection in action (verb) naming in AWS. METHOD 12 AWS and 12 TFA named line drawings depicting actions using verbs. Half of the pictures had high-agreement action names and the other half low-agreement action names. Naming accuracy and reaction times (RT), and event-related potentials (ERPs) time-locked to picture onset, were compared between groups. RESULTS Naming RTs were slower for low- versus high-agreement trials, and the magnitude of this effect was larger in AWS versus TFA. Delta-plot analysis of naming RTs revealed that individual differences in selective inhibition were associated with the agreement effect on naming RTs in AWS but not TFA. Action naming elicited frontal-central N2 activity in both agreement conditions in TFA but not AWS. Additionally, a later, posterior P3b component was affected by agreement in TFA only. In AWS, low-agreement action naming elicited frontal P3a activation. CONCLUSIONS Results suggest that cognitive control of action name selection was qualitatively different between groups. In TFA, cognitive control of lexical selection in action naming involved nonselective inhibition, as well as more efficient working memory updating on high- versus low-agreement trials. In AWS, cognitive control of low-agreement action naming involved increased focal attention. Individual differences in selective inhibition may have moderated cognitive control of action naming in AWS.
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Affiliation(s)
- Nathan D Maxfield
- University of South Florida, Department of Communication Sciences & Disorders, 4202 East Fowler Avenue, PCD1017, Tampa, FL, 33620, United States.
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Ofoe LC, Anderson JD. Complex nonverbal response inhibition and stopping impulsivity in childhood stuttering. JOURNAL OF FLUENCY DISORDERS 2021; 70:105877. [PMID: 34534900 PMCID: PMC8629930 DOI: 10.1016/j.jfludis.2021.105877] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 08/11/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
PURPOSE The primary purpose of this study was to examine complex nonverbal response inhibition and stopping impulsivity in children who do (CWS) and do not stutter (CWNS). METHOD A total of 30 CWS and 30 CWNS between the ages of 3;1 and 6;0 (years; months) performed the Peg-Tapping Task (PTT; Diamond & Taylor, 1996; Luria, 1966), in which children were required to tap a dowel once when an examiner taps twice and vice versa. The main dependent variables were the number of practice trials, response accuracy, response latency for accurate responses, and the number of extra taps (i.e., tapping more than two times). RESULTS The CWS were less accurate and slower on the PTT than the CWNS, with no differences in the number of practice trials. Furthermore, the CWS, especially boys, produced more extra taps than the CWNS. CONCLUSIONS Findings revealed that preschool CWS have weaknesses in complex response inhibition and stopping impulsivity in the nonverbal domain compared to CWNS. Taken together, these findings along with those of previous studies indicate that CWS may have weaknesses in inhibition and impulsivity in the nonverbal domain as well as the verbal domain, suggesting a domain-general weakness.
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Affiliation(s)
- Levi C Ofoe
- Department of Speech and Hearing Sciences, Indiana University, Bloomington, United States.
| | - Julie D Anderson
- Department of Speech and Hearing Sciences, Indiana University, Bloomington, United States
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Treleaven SB, Coalson GA. Verbal Response Inhibition in Adults Who Stutter. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2021; 64:3382-3397. [PMID: 34403265 PMCID: PMC8642087 DOI: 10.1044/2021_jslhr-20-00739] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 04/01/2021] [Accepted: 05/09/2021] [Indexed: 05/30/2023]
Abstract
Purpose Adults who stutter (AWS) often attempt, with varying degrees of success, to suppress their stuttered speech. The ability to effectively suppress motoric behavior after initiation relies on executive functions such as nonselective inhibition. Although previous studies found that AWS were slower to inhibit manual, button-press response than adults who do not stutter (AWNS), research has yet to confirm a consistent relationship between manual and verbal inhibition. No study has examined verbal inhibition ability in AWS. The purpose of this study, therefore, is to compare verbal response inhibition between AWS and AWNS, and compare verbal response inhibition to both the overt stuttering and the lived experience of stuttering. Method Thirty-four adults (17 AWNS, 17 AWS) completed one manual and three verbal stop-signal tasks. AWS were assessed for stuttering severity (Stuttering Severity Instrument-Fourth Edition: SSI-4) and experience with stuttering (Overall Assessment of the Speaker's Experience With Stuttering [OASES]). Results Results indicate no correlation between manual and verbal inhibition for either group. Generalized linear mixed-model analyses suggested no significant group differences in manual or verbal inhibition. Manual and verbal inhibition did not predict SSI-4 in AWS. However, verbal inhibition was uniquely associated with OASES scores. Conclusion Although underlying manual and verbal inhibition was comparable between AWS and AWNS, verbal inhibition may be linked to the adverse experience of stuttering rather than the overt symptoms of stuttering severity. Supplemental Material https://doi.org/10.23641/asha.15145185.
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Towards real-world generalizability of a circuit for action-stopping. Nat Rev Neurosci 2021; 22:538-552. [PMID: 34326532 PMCID: PMC8972073 DOI: 10.1038/s41583-021-00485-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/04/2021] [Indexed: 02/07/2023]
Abstract
Two decades of cross-species neuroscience research on rapid action-stopping in the laboratory has provided motivation for an underlying prefrontal-basal ganglia circuit. Here we provide an update of key studies from the past few years. We conclude that this basic neural circuit is on increasingly firm ground, and we move on to consider whether the action-stopping function implemented by this circuit applies beyond the simple laboratory stop signal task. We advance through a series of studies of increasing 'real-worldness', starting with laboratory tests of stopping of speech, gait and bodily functions, and then going beyond the laboratory to consider neural recordings and stimulation during moments of control presumably required in everyday activities such as walking and driving. We end by asking whether stopping research has clinical relevance, focusing on movement disorders such as stuttering, tics and freezing of gait. Overall, we conclude there are hints that the prefrontal-basal ganglia action-stopping circuit that is engaged by the basic stop signal task is recruited in myriad scenarios; however, truly proving this for real-world scenarios requires a new generation of studies that will need to overcome substantial technical and inferential challenges.
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Maxfield ND. Inhibitory Control of Lexical Selection in Adults who Stutter. JOURNAL OF FLUENCY DISORDERS 2020; 66:105780. [PMID: 32950028 PMCID: PMC7704578 DOI: 10.1016/j.jfludis.2020.105780] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 08/05/2020] [Accepted: 08/07/2020] [Indexed: 06/01/2023]
Abstract
PURPOSE Based on previous evidence that lexical selection may operate differently in adults who stutter (AWS) versus typically-fluent adults (TFA), and that atypical attentional processing may be a contributing factor, the purpose of this study was to investigate inhibitory control of lexical selection in AWS. METHOD 12 AWS and 12 TFA completed two tasks. One was a picture naming task featuring High and Low Agreement object naming. Naming accuracy and reaction times (RT), and event-related potentials (ERPs) time-locked to picture onset, were recorded. Second was a flanker task featuring Congruent and Incongruent arrow arrays. Push-button accuracy and RTs, and ERPs time-locked to arrow array onset, were recorded. RESULTS Low Agreement pictures were named less accurately and slower than High Agreement pictures in both Groups. The magnitude of the Agreement effect on naming RTs was larger in AWS versus TFA. Delta-plot analysis revealed that the Agreement effect was positively correlated with individual differences in inhibition in TFA but not in AWS. Moreover, Low Agreement pictures elicited negative-going ERP activity relative to High Agreement pictures in both Groups. However, the scalp topography of this effect was markedly reduced in AWS versus TFA. For the Flanker task, Congruency affected push-button accuracy and RTs, and N2 amplitudes, similarly between groups. CONCLUSIONS Results point to a selective deficit in inhibitory control of lexical selection in AWS. Potential pathways between diminished inhibitory control of lexical selection, speech motor control and stuttering are discussed.
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Affiliation(s)
- Nathan D Maxfield
- University of South Florida, Department of Communication Sciences & Disorders, 4202 East Fowler Avenue, PCD1017, Tampa, FL, 33620, United States.
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12
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Treleaven SB, Coalson GA. Manual response inhibition and quality of life in adults who stutter. JOURNAL OF COMMUNICATION DISORDERS 2020; 88:106053. [PMID: 33065458 PMCID: PMC7736488 DOI: 10.1016/j.jcomdis.2020.106053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 06/23/2020] [Accepted: 08/24/2020] [Indexed: 06/01/2023]
Abstract
BACKGROUND A considerable amount of research has identified inhibition differences, including slower inhibition of manual responses, in people who stutter. Recent investigations have failed to link slowed motor inhibition with overt stuttering severity. This study investigated the potential relationship between slowed manual response inhibition and the negative impact of stuttering upon individual lives of adults who stutter (AWS). METHODS Thirty-four adults (AWS, n = 17; AWNS, n = 17) matched by nonverbal IQ completed a manual stop-signal task and provided a conversational speech sample. Motor inhibition latency for AWS and AWNS were compared. For AWS, motor inhibition latency was compared to the four subsections of the Overall Assessment of the Speaker's Experience with Stuttering (OASES; Yaruss & Quesal, 2006; General Information, Reactions to Stuttering, Communication in Daily Situations, Quality of Life). RESULTS Similar to previous studies, AWS were significantly slower to inhibit inaccurate manual responses than AWNS. Quality of Life subtest of the OASES was found to significantly predict inhibition latency. CONCLUSION These data replicate findings that indicate that AWS exhibit slower manual inhibition latency, and suggest that these inhibition differences may be associated with an individual's negative experience with stuttering rather than stuttering severity.
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Affiliation(s)
- Shanley B Treleaven
- Louisiana State University, Department of Communication Sciences and Disorders, 68 Hatcher Hall, Field House Drive, Baton Rouge, LA 70803, United States.
| | - Geoffrey A Coalson
- Louisiana State University, Department of Communication Sciences and Disorders, 68 Hatcher Hall, Field House Drive, Baton Rouge, LA 70803, United States
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Doneva SP. Adult stuttering and attentional ability: A meta-analytic review. INTERNATIONAL JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2020; 22:444-453. [PMID: 31590580 DOI: 10.1080/17549507.2019.1665710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Purpose: The study presents the first review in which the link between attentional ability and developmental stuttering is explored. The review aimed to summarise the published research literature and provide a more conclusive understanding as to the relationship between stuttering and attention.Method: To be included in this review, the studies had to compare the attentional performance of adult people who stutter (PWS) and people who do not stutter (PWNS) over the age of 18 years with a validated psychometric instrument for measuring attentional ability. Articles were searched in four electronic databases where each of the following search terms (attention, vigilance, inhibitory, inhibition, interference, executive and processing) was cross-referenced with each of the following terms (stutter, stammer, speech disfluency and speech dysfluency). A total of 21 studies met the inclusion criteria to be submitted into a meta-analysis.Result: The results of the main meta-analysis, which included all selected studies, demonstrated that PWS had a significantly worse attentional performance as compared to PWNS. Two further meta-analyses on selective attention and dual tasking performance confirmed the latter finding. Importantly, however, the effect was not present in all studies.Conclusion: Our findings should be taken as an indication that stuttering sometimes (but not always) manifests together with poorer attentional ability, such that the identified link does not affect all PWS. These results provide support for the notion that there is a close association between stuttering and attentional ability in a subgroup of PWS, highlighting potential practical implications for stuttering treatment.
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Affiliation(s)
- Silviya P Doneva
- Department of Health Sciences, University of Suffolk, Ipswich, United Kingdom of Great Britain and Northern Ireland
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Gkalitsiou Z, Byrd C, Griffin Z. Executive Control in Adults Who Stutter: The Antisaccade Task. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2020; 63:1688-1699. [PMID: 32437256 DOI: 10.1044/2020_jslhr-19-00045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Purpose The purpose of this study was to investigate executive control in adults who stutter (AWS) and adults who do not stutter (AWNS) via a nonspeech paradigm, wherein eye movements were monitored (i.e., antisaccade task). Processes involved in an antisaccade task include working memory, attention, and voluntary motor control, but the task primarily provides insight into inhibitory control. Method Seventeen AWS (14 men, three women; M = 23.41 years) and 17 AWNS (M = 23.29 years) were presented with a combination of prosaccade (i.e., looking toward a target) and antisaccade (i.e., suppress a reflexive saccade toward the target and look in the opposite direction) trials. The distance of the target from the center of the screen was also manipulated (i.e., 5.5o = short distance and 10.8o = long distance). Data for accuracy and reaction time of the first accurate saccade were collected and analyzed. Results No difference was found between AWS and AWNS in accuracy or in reaction time. Both groups were more accurate in the prosaccade than the antisaccade trials and in the long compared to the short distance trials. Furthermore, both groups demonstrated longer saccade latencies for long compared to short distances and for antisaccade compared to prosaccade trials. Conclusions Preliminary results do not support deficits in inhibition in AWS during a motorically simple, non-speech-related oculomotor task, but additional research is warranted.
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Affiliation(s)
- Zoi Gkalitsiou
- Department of Communication Sciences and Disorders, The University of Texas at Austin
| | - Courtney Byrd
- Department of Communication Sciences and Disorders, The University of Texas at Austin
| | - Zenzi Griffin
- Department of Psychology, The University of Texas at Austin
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Sengupta R, Yaruss JS, Loucks TM, Gracco VL, Pelczarski K, Nasir SM. Theta Modulated Neural Phase Coherence Facilitates Speech Fluency in Adults Who Stutter. Front Hum Neurosci 2019; 13:394. [PMID: 31798431 PMCID: PMC6878001 DOI: 10.3389/fnhum.2019.00394] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 10/22/2019] [Indexed: 12/03/2022] Open
Abstract
Adults who stutter (AWS) display altered patterns of neural phase coherence within the speech motor system preceding disfluencies. These altered patterns may distinguish fluent speech episodes from disfluent ones. Phase coherence is relevant to the study of stuttering because it reflects neural communication within brain networks. In this follow-up study, the oscillatory cortical dynamics preceding fluent speech in AWS and adults who do not stutter (AWNS) were examined during a single-word delayed reading task using electroencephalographic (EEG) techniques. Compared to AWNS, fluent speech preparation in AWS was characterized by a decrease in theta-gamma phase coherence and a corresponding increase in theta-beta coherence level. Higher spectral powers in the beta and gamma bands were also observed preceding fluent utterances by AWS. Overall, there was altered neural communication during speech planning in AWS that provides novel evidence for atypical allocation of feedforward control by AWS even before fluent utterances.
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Affiliation(s)
- Ranit Sengupta
- Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL, United States
| | - J Scott Yaruss
- Department of Communicative Sciences and Disorders, Michigan State University, East Lansing, MI, United States
| | - Torrey M Loucks
- Department of Communication Sciences and Disorders, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, AB, Canada.,Institute for Stuttering Treatment and Research, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, AB, Canada
| | | | - Kristin Pelczarski
- School of Family Studies and Human Services, Kansas State University, Manhattan, KS, United States
| | - Sazzad M Nasir
- Haskins Laboratories, New Haven, CT, United States.,Indiana Academy, Ball State University, Muncie, IN, United States
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16
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Anderson JD, Ofoe LC. The Role of Executive Function in Developmental Stuttering. Semin Speech Lang 2019; 40:305-319. [PMID: 31311055 DOI: 10.1055/s-0039-1692965] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Developmental stuttering is a complex disorder and children who stutter form a heterogeneous group. Most contemporary researchers would agree that multiple factors, including those associated with linguistic, motor, sensory, and emotional processes, are likely involved in its development and/or maintenance. There is growing evidence, however, that cognitive processes also play a role. In this article, we briefly review behavioral and parent-report studies of executive function in children who stutter, the findings of which have generally suggested that these skills may be challenging for at least some children who stutter. We then consider how deficits in executive function could provide an explanatory account for not only the multifactorial nature of developmental stuttering but also the considerable amount of variability that exists among individuals who stutter.
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Affiliation(s)
- Julie D Anderson
- Department of Speech and Hearing Sciences, Indiana University, Bloomington, Indiana
| | - Levi C Ofoe
- Department of Speech and Hearing Sciences, Indiana University, Bloomington, Indiana
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17
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Montag C, Bleek B, Reuter M, Müller T, Weber B, Faber J, Markett S. Ventral striatum and stuttering: Robust evidence from a case-control study applying DARTEL. Neuroimage Clin 2019; 23:101890. [PMID: 31255948 PMCID: PMC6606830 DOI: 10.1016/j.nicl.2019.101890] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 05/30/2019] [Accepted: 06/04/2019] [Indexed: 10/26/2022]
Abstract
A prominent theory of developmental stuttering highlights (dys-)function of the basal ganglia (and in particular the ventral striatum) as a main neural mechanism behind this speech disorder. Although the theory is intriguing, studies on gray matter volume differences in the basal ganglia between people who stutter and control persons have reported heterogeneous findings, either showing more or less gray matter volume of the aforementioned brain structure across the brain's hemispheres. Moreover, some studies did not observe any differences at all. From today's perspective several of the earlier studies are rather underpowered and also used less powerful statistical approaches to investigate differences in brain structure between people who stutter and controls. Therefore, the present study contrasted a comparably larger sample of n = 36 people who stutter with n = 34 control persons and applied the state of the art DARTEL algorithm (Diffeomorphic Anatomical Registration Through Exponentiated Lie algebra) to analyze the available brain data. In the present data set stuttering was associated with higher gray matter volume of the right caudate and putamen region of the basal ganglia in patients. Our observation strongly supports a recent finding reporting a larger nucleus accumbens in the right hemisphere in people who stutter when compared to control persons. The present findings are discussed in the context of both compensatory effects of the brain and putative therapeutic effects due to treatment of stuttering.
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Affiliation(s)
- Christian Montag
- Department of Molecular Psychology, Institute of Psychology and Education, Ulm University, Germany.
| | - Benjamin Bleek
- Department of Psychology, University of Bonn, Bonn, Germany
| | - Martin Reuter
- Department of Psychology, University of Bonn, Bonn, Germany; Center for Economics and Neuroscience (CENs), University of Bonn, Bonn, Germany
| | - Thilo Müller
- Department for the Treatment of Stuttering, LVR Clinic Bonn, Bonn, Germany
| | - Bernd Weber
- Center for Economics and Neuroscience (CENs), University of Bonn, Bonn, Germany; Department for NeuroCognition, Life & Brain Center, Germany; Institute of Experimental Epileptology and Cognition Research, University Hospital of Bonn, Germany
| | - Jennifer Faber
- Department of Neurology, University Hospital Bonn, Bonn, Germany; German Center for Neurodegenerative Diseases, Bonn, Germany
| | - Sebastian Markett
- Department of Psychology, Humboldt Universität zu Berlin, Berlin, Germany.
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18
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Sares AG, Deroche MLD, Shiller DM, Gracco VL. Adults who stutter and metronome synchronization: evidence for a nonspeech timing deficit. Ann N Y Acad Sci 2019; 1449:56-69. [PMID: 31144336 DOI: 10.1111/nyas.14117] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 04/16/2019] [Accepted: 04/21/2019] [Indexed: 12/30/2022]
Abstract
Speech timing deficits have been proposed as a causal factor in the disorder of stuttering. The question of whether individuals who stutter have deficits in nonspeech timing is one that has been revisited often, with conflicting results. Here, we uncover subtle differences in a manual metronome synchronization task that included tempo changes with adults who stutter and fluent speakers. We used sensitive circular statistics to examine both asynchrony and consistency in motor production. While both groups displayed a classic negative mean asynchrony (tapping before the beat), individuals who stutter anticipated the beat even more than their fluent peers, and their consistency was particularly affected at slow tempi. Surprisingly, individuals who stutter did not have problems with interval correction at tempo changes. We also examined the influence of music experience on synchronization behavior in both groups. While music perception and training were related to synchronization behavior in fluent participants, these correlations were not present for the stuttering group; however, one measure of stuttering severity (self-rated severity) was negatively correlated with music training. Overall, we found subtle differences in paced auditory-motor synchronization in individuals who stutter, consistent with a timing problem extending to nonspeech.
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Affiliation(s)
- Anastasia G Sares
- Integrated Program in Neuroscience, Montréal, Quebec, Canada.,Centre for Research on Brain, Language and Music, McGill University, Montréal, Quebec, Canada
| | - Mickael L D Deroche
- School of Communication Sciences and Disorders, Montréal, Quebec, Canada.,Centre for Research on Brain, Language and Music, McGill University, Montréal, Quebec, Canada
| | - Douglas M Shiller
- Centre for Research on Brain, Language and Music, McGill University, Montréal, Quebec, Canada.,École d'orthophonie et d'audiologie, Université de Montréal, Montréal, Quebec, Canada
| | - Vincent L Gracco
- Integrated Program in Neuroscience, Montréal, Quebec, Canada.,School of Communication Sciences and Disorders, Montréal, Quebec, Canada.,Centre for Research on Brain, Language and Music, McGill University, Montréal, Quebec, Canada.,Haskins Laboratories, New Haven, Connecticut
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19
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Neef NE, Anwander A, Bütfering C, Schmidt-Samoa C, Friederici AD, Paulus W, Sommer M. Structural connectivity of right frontal hyperactive areas scales with stuttering severity. Brain 2019; 141:191-204. [PMID: 29228195 PMCID: PMC5837552 DOI: 10.1093/brain/awx316] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 10/11/2017] [Indexed: 11/14/2022] Open
Abstract
A neuronal sign of persistent developmental stuttering is the magnified coactivation of right frontal brain regions during speech production. Whether and how stuttering severity relates to the connection strength of these hyperactive right frontal areas to other brain areas is an open question. Scrutinizing such brain–behaviour and structure–function relationships aims at disentangling suspected underlying neuronal mechanisms of stuttering. Here, we acquired diffusion-weighted and functional images from 31 adults who stutter and 34 matched control participants. Using a newly developed structural connectivity measure, we calculated voxel-wise correlations between connection strength and stuttering severity within tract volumes that originated from functionally hyperactive right frontal regions. Correlation analyses revealed that with increasing speech motor deficits the connection strength increased in the right frontal aslant tract, the right anterior thalamic radiation, and in U-shaped projections underneath the right precentral sulcus. In contrast, with decreasing speech motor deficits connection strength increased in the right uncinate fasciculus. Additional group comparisons of whole-brain white matter skeletons replicated the previously reported reduction of fractional anisotropy in the left and right superior longitudinal fasciculus as well as at the junction of right frontal aslant tract and right superior longitudinal fasciculus in adults who stutter compared to control participants. Overall, our investigation suggests that right fronto-temporal networks play a compensatory role as a fluency enhancing mechanism. In contrast, the increased connection strength within subcortical-cortical pathways may be implied in an overly active global response suppression mechanism in stuttering. Altogether, this combined functional MRI–diffusion tensor imaging study disentangles different networks involved in the neuronal underpinnings of the speech motor deficit in persistent developmental stuttering.
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Affiliation(s)
- Nicole E Neef
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.,Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany
| | - Alfred Anwander
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Christoph Bütfering
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany
| | | | - Angela D Friederici
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Walter Paulus
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany
| | - Martin Sommer
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, Germany
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20
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Whillier A, Hommel S, Neef NE, Wolff von Gudenberg A, Paulus W, Sommer M. Adults who stutter lack the specialised pre-speech facilitation found in non-stutterers. PLoS One 2018; 13:e0202634. [PMID: 30303960 PMCID: PMC6179203 DOI: 10.1371/journal.pone.0202634] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 08/07/2018] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVES Persistent developmental stuttering is a speech fluency disorder defined by its symptoms, where the underlying neurophysiological causes remain uncertain. This study examined the underlying neurophysiological mechanisms of the speech planning process, using facilitation in the motor cortex during speech preparation as an analogue. METHODS transcranial magnetic stimulation (TMS) pulses induced motor evoked potentials (MEPs), which were recorded from the tongue. Eighteen adults who stutter (AWS) and 17 adults who do not stutter (ANS) completed three experiments, which involved reading a German prefix+verb utterance from a screen. Each experiment involved 120 trials with three distinct levels of speech production: immediate speech, delayed speech without pacing and delayed speech with predefined pacing. TMS was applied shortly before speech onset. Trial MEPs were normalised to average non-speech MEPs. MEP amplitude, MEP facilitation ratio (amplitude: pre-speech offset) and group difference were the outcomes of interest analysed by multiple regression, as well as speech reaction time analysed by correlation. RESULTS MEP values were 11·1%-23·4% lower in AWS than ANS (by standardised Beta), across all three experiments. MEP facilitation ratio slopes were also 4·9%-18·3% flatter in AWS than ANS across all three experiments. Reaction times for AWS were only significantly slower than for ANS in immediate speech and predefined pacing experiments. No stuttering was detected during the trials. The group difference in immediate speech was 100% and 101% greater than the other two experiments respectively. DISCUSSION While performance of both ANS and AWS worsens under disturbed speech conditions, greater disturbance conditions affected controls worse than AWS. Future research and therapy in stuttering should focus on non-disturbed speech.
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Affiliation(s)
- Alexander Whillier
- Department of Clinical Neurophysiology, University Medical Centre Göttingen, Göttingen, Germany
| | - Sina Hommel
- Department of Clinical Neurophysiology, University Medical Centre Göttingen, Göttingen, Germany
| | - Nicole E. Neef
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Science, Leipzig, Germany
| | | | - Walter Paulus
- Department of Clinical Neurophysiology, University Medical Centre Göttingen, Göttingen, Germany
| | - Martin Sommer
- Department of Clinical Neurophysiology, University Medical Centre Göttingen, Göttingen, Germany
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21
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Eggers K, De Nil LF, Van den Bergh BRH. Exogenously triggered response inhibition in developmental stuttering. JOURNAL OF FLUENCY DISORDERS 2018; 56:33-44. [PMID: 29494965 DOI: 10.1016/j.jfludis.2018.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 11/08/2017] [Accepted: 02/16/2018] [Indexed: 06/08/2023]
Abstract
PURPOSE The purpose of the present study was to examine relations between children's exogenously triggered response inhibition and stuttering. METHOD Participants were 18 children who stutter (CWS; mean age = 9;01 years) and 18 children who not stutter (CWNS; mean age = 9;01 years). Participants were matched on age (±3 months) and gender. Response inhibition was assessed by a stop signal task (Verbruggen, Logan, & Stevens, 2008). RESULTS Results suggest that CWS, compared to CWNS, perform comparable to CWNS in a task where response control is externally triggered. CONCLUSIONS Our findings seem to indicate that previous questionnaire-based findings (Eggers, De Nil, & Van den Bergh, 2010) of a decreased efficiency of response inhibition cannot be generalized to all types of response inhibition.
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Affiliation(s)
- Kurt Eggers
- Dept. of Speech-Language Therapy, Thomas More University College, Belgium; Experimental Otorinolaryngology, Dept. of Neurosciences, University of Leuven, Belgium; Dept. of Psychology and Speech-Language Pathology, University of Turku, Finland.
| | - Luc F De Nil
- Experimental Otorinolaryngology, Dept. of Neurosciences, University of Leuven, Belgium; Dept. of Speech-Language Pathology, University of Toronto, Canada.
| | - Bea R H Van den Bergh
- Dept. of Psychology, Tilburg University, The Netherlands; Dept. of Psychology, University of Leuven, Belgium.
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22
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Johari K, Behroozmand R. Temporal predictive mechanisms modulate motor reaction time during initiation and inhibition of speech and hand movement. Hum Mov Sci 2017; 54:41-50. [DOI: 10.1016/j.humov.2017.03.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 01/20/2017] [Accepted: 03/22/2017] [Indexed: 11/28/2022]
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23
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Metzger FL, Auer T, Helms G, Paulus W, Frahm J, Sommer M, Neef NE. Shifted dynamic interactions between subcortical nuclei and inferior frontal gyri during response preparation in persistent developmental stuttering. Brain Struct Funct 2017; 223:165-182. [PMID: 28741037 PMCID: PMC5772149 DOI: 10.1007/s00429-017-1476-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 07/07/2017] [Indexed: 11/29/2022]
Abstract
Persistent developmental stuttering is associated with basal ganglia dysfunction or dopamine dysregulation. Here, we studied whole-brain functional connectivity to test how basal ganglia structures coordinate and reorganize sensorimotor brain networks in stuttering. To this end, adults who stutter and fluent speakers (control participants) performed a response anticipation paradigm in the MRI scanner. The preparation of a manual Go/No-Go response reliably produced activity in the basal ganglia and thalamus and particularly in the substantia nigra. Strikingly, in adults who stutter, substantia nigra activity correlated positively with stuttering severity. Furthermore, functional connectivity analyses yielded altered task-related network formations in adults who stutter compared to fluent speakers. Specifically, in adults who stutter, the globus pallidus and the thalamus showed increased network synchronization with the inferior frontal gyrus. This implies dynamic shifts in the response preparation-related network organization through the basal ganglia in the context of a non-speech motor task in stuttering. Here we discuss current findings in the traditional framework of how D1 and D2 receptor activity shapes focused movement selection, thereby suggesting a disproportional involvement of the direct and the indirect pathway in stuttering.
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Affiliation(s)
- F Luise Metzger
- Department of Clinical Neurophysiology, Georg August University, Göttingen, Germany
| | - Tibor Auer
- Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für Biophysikalische Chemie, Göttingen, Germany.,MRC Cognition and Brain Sciences Unit, Cambridge, UK.,Department of Psychology, Royal Holloway, University of London, Egham, UK
| | - Gunther Helms
- Department of Medical Radiation Physics, Lund University, Lund, Sweden
| | - Walter Paulus
- Department of Clinical Neurophysiology, Georg August University, Göttingen, Germany
| | - Jens Frahm
- Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für Biophysikalische Chemie, Göttingen, Germany
| | - Martin Sommer
- Department of Clinical Neurophysiology, Georg August University, Göttingen, Germany
| | - Nicole E Neef
- Department of Clinical Neurophysiology, Georg August University, Göttingen, Germany. .,Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstraße 1a, 04103, Leipzig, Germany.
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24
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Busan P, Battaglini P, Sommer M. Transcranial magnetic stimulation in developmental stuttering: Relations with previous neurophysiological research and future perspectives. Clin Neurophysiol 2017; 128:952-964. [DOI: 10.1016/j.clinph.2017.03.039] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 03/14/2017] [Accepted: 03/22/2017] [Indexed: 10/19/2022]
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