Araceli L. Peretti¹, Nidia Patricia Cedeño Ortiz 2
¹ Speech-Language Pathologist, licaraceliperetti@gmail.com
2 Speech-Language Pathologist, Therapy Laser PG, ORCID 0000-0001-8325-6113, kattie456@yahoo.com
 

Abstract
The incorporation of emerging technologies into speech-language pathology has expanded diagnostic and therapeutic possibilities for patients with disorders affecting human communication. Among these technologies, photobiomodulation, electrical stimulation, therapeutic ultrasound, thermography, and instrumental tools for the functional assessment of swallowing have gained increasing clinical relevance.

The aim of this study was to describe the clinical application of these technologies in three patients with neurological disorders secondary to ischemic stroke, trigeminal neuralgia, and Guillain-Barré syndrome. A descriptive case series was conducted involving interventions based on orofacial myofunctional assessment, functional analysis, and the application of complementary technological resources.

Clinical outcomes demonstrated functional improvements in communication, swallowing, mastication, and social participation. These findings suggest that emerging technologies

may serve as valuable adjunctive resources when integrated into speech-language pathology interventions grounded in clinical reasoning and neurofunctional principles.

Keywords: photobiomodulation, orofacial myology, dysphagia, neurological rehabilitation, speech-language pathology, transcranial photobiomodulation.

 

Introduction
Human communication results from a complex interaction among neurological, muscular, sensory, and cognitive systems that enable the coordinated execution of functions such as feeding, swallowing, breathing, voice production, speech, and language. When these systems are compromised by neurological, neuromuscular, or pain-related disorders, significant functional limitations may arise, negatively affecting an individual's quality of life and social participation.

Over recent decades, speech-language pathology rehabilitation has evolved from approaches primarily focused on functional compensation toward models that seek to harness neuroplasticity and functional reorganization of the nervous system (Jiang et al., 2024; Leinweber et al., 2023). This conceptual shift has promoted the incorporation of emerging technologies designed to complement traditional diagnostic and therapeutic procedures, enabling interventions targeting both peripheral structures of the stomatognathic system and neural networks involved in the motor and sensory control of communication.

Among these innovations, photobiomodulation (PBM), also known as low-level laser therapy (LLLT), has attracted increasing attention due to its ability to modulate cellular processes without producing significant thermal effects. PBM employs red or near- infrared light to interact with intracellular chromophores, particularly mitochondrial cytochrome c oxidase, enhancing adenosine triphosphate (ATP) production, reducing oxidative stress, modulating inflammatory mediators, and activating tissue repair mechanisms (Nairuz et al., 2024).

Current evidence suggests that PBM may promote neuroprotection, neurogenesis, angiogenesis, and neuroplasticity, all of which may contribute to functional recovery in neurological disorders (Shivappa et al., 2025). Furthermore, transcranial photobiomodulation has demonstrated effects on cerebral perfusion, tissue oxygenation, and neuronal metabolic activity, factors considered essential in recovery processes following acquired brain injury (Lin et al., 2024).
Transcranial PBM has been investigated in several clinical conditions, including stroke, traumatic brain injury, cognitive impairment, Parkinson’s disease, and other neurological disorders associated with motor and cognitive dysfunction (Ren et al., 2026). Reported mechanisms include enhanced mitochondrial respiration, increased cerebral blood flow, reduced neuroinflammation, and facilitation of adaptive neuroplastic processes (Tang et al., 2025).

From the perspective of orofacial myology, these technological advances are particularly relevant because stomatognathic functions depend on the integrated activity of peripheral musculature and distributed cortical and subcortical neural networks. Mastication, swallowing, and speech should not be understood as exclusively muscular phenomena but rather as highly specialized neuromotor processes requiring temporal precision, synchrony, sensory integration, and efficient motor control.
In patients with stroke, trigeminal neuralgia, and Guillain-Barré syndrome, disruption of these networks often results in functional deficits affecting feeding and communication. Therefore, it is necessary to investigate therapeutic strategies capable of simultaneously addressing both peripheral and central components involved in functional performance.

Within this context, the integration of photobiomodulation, functional electrical stimulation, therapeutic ultrasound, clinical thermography, and acoustic swallowing analysis represents an innovative approach within contemporary speech-language pathology rehabilitation programs.

The objective of this study was to describe the clinical application of these technologies in three patients with neurological disorders, analyzing functional changes observed in feeding, communication, and social participation.
 

Materials and Methods
Study Design
A descriptive case series was conducted involving three patients receiving specialized speech-language pathology intervention in both hospital-based and outpatient settings.
 

Participants
Three patients presenting neurological disorders with associated impairments in communication and feeding functions were included:
• Case 1: A 67-year-old male diagnosed with ischemic stroke involving the left middle cerebral artery.
• Case 2: A 77-year-old female diagnosed with trigeminal neuralgia and masticatory dysfunction.
• Case 3: A 77-year-old male diagnosed with Guillain-Barré syndrome presenting with dysphagia, tracheostomy, and gastrostomy.
 

Clinical Assessment
All participants underwent a comprehensive assessment protocol that included:
• Speech-language pathology evaluation.
• Orofacial myofunctional assessment.
• Analysis of laryngeal fixation patterns.
• Functional evaluation of the stomatognathic system.
• Clinical observation of communication and feeding functions.
• Acoustic swallowing analysis when clinical conditions permitted.
 

Intervention Protocol
Interventions were individualized according to each patient's functional impairments and therapeutic goals. Treatment combined:
• Targeted photobiomodulation.
• Transcranial photobiomodulation.
• Orofacial myology techniques.
• Functional re-education strategies.
• Electrical stimulation when clinically indicated.
• Therapeutic ultrasound in specific cases.
Table 1
Photobiomodulation Protocol Parameters Used During Intervention

Note. Treatment parameters were adjusted according to individual functional needs and rehabilitation goals.
Targeted photobiomodulation was delivered using an F3WW Low-Level Laser Therapy Light device operating at 650 nm with a power output of 200 mW. Transcranial photobiomodulation combined wavelengths of 650 nm and 850 nm delivered at frequencies of 10 Hz and 40 Hz for five minutes per frequency.

Table 2
Neurofunctional Areas Targeted Through Transcranial Photobiomodulation
Note. Neurofunctional areas were selected according to the clinical presentation and functional impairments observed in each patient.
 

Results
Case 1: Ischemic Stroke
The patient presented with expressive aphasia, dysphagia, hypogeusia, and anosmia. Clinical assessment revealed functional alterations of the stomatognathic system and a laryngeal fixation pattern characterized by a low, posteriorized laryngeal position with rightward rotation.
Following 12 treatment sessions, progressive improvements were observed in oral communication and feeding abilities. At follow-up, the patient had resumed occupational activities and maintained functional independence.

Case 2: Trigeminal Neuralgia
The patient sought treatment due to severe facial pain associated with masticatory dysfunction. Following eight treatment sessions, a progressive reduction in pain intensity
was observed, accompanied by improved mandibular mobility and restoration of chewing efficiency.
The patient was able to resume comfortable oral feeding and reported improved participation in family and social activities.

Case 3: Guillain-Barré Syndrome
The patient presented with severe dysphagia requiring tracheostomy and gastrostomy.
Following an intervention program consisting of transcranial photobiomodulation, orofacial myofunctional therapy, and reorganization of laryngeal fixation patterns, progressive improvement in swallowing function was observed.
After five treatment sessions, oral feeding was re-established, the tracheostomy cannula was removed, and gastrostomy feeding was discontinued, resulting in increased functional independence.

Table 3
Clinical Outcomes Observed Following Intervention
Note. Outcomes correspond to clinical observations documented throughout the rehabilitation process and follow-up period.
 

Discussion
The findings of this case series suggest that the integration of emerging technologies, particularly photobiomodulation, within speech-language pathology rehabilitation programs may provide meaningful support for functional recovery in patients presenting with neurological and neuromuscular disorders. Across the three cases, improvements were observed in swallowing, communication, mastication, and functional independence, supporting the potential clinical value of combining neurofunctional rehabilitation strategies with technology-assisted interventions.

From a physiological perspective, these outcomes may be associated with the biological mechanisms described for photobiomodulation therapy. Current evidence indicates that light energy absorbed by mitochondrial chromophores enhances ATP production and triggers a cascade of cellular responses involving oxidative stress regulation, anti-inflammatory effects, angiogenesis, and tissue repair (Nairuz et al., 2024; Shivappa et al., 2025). These mechanisms have been proposed as key contributors to neurological recovery and functional restoration following injury to the central or peripheral nervous system.
In the patient with ischemic stroke of the left middle cerebral artery, improvements in communication and swallowing function may be explained by the interaction between conventional rehabilitation and neuroplastic processes potentially facilitated by transcranial photobiomodulation. Previous studies have reported that transcranial PBM may positively influence cerebral perfusion, neuronal metabolism, and adaptive reorganization of neural networks involved in cognitive and motor recovery (Tang et al., 2025; Ren et al., 2026). Considering that language and swallowing involve distributed sensorimotor networks, interventions targeting both peripheral and central mechanisms may have contributed to the functional gains observed in this case.

Similarly, the outcomes obtained in the patient with trigeminal neuralgia are consistent with previous reports describing analgesic and anti-inflammatory effects of low-level laser therapy. Photobiomodulation has been associated with modulation of neuronal excitability, reduction of peripheral sensitization, and improvement of neuromuscular function, factors that may contribute to pain reduction and restoration of oral functions (Korada et al., 2023; González-Muñoz et al., 2023). In the present case, pain reduction was accompanied by progressive recovery of masticatory efficiency, ultimately improving nutritional intake and quality of life.

The patient with Guillain-Barré syndrome demonstrated a notable recovery of swallowing function and feeding autonomy. Although the pathophysiological mechanisms underlying this recovery cannot be directly attributed to photobiomodulation, emerging evidence suggests that PBM may support neuroprotection, tissue regeneration, and peripheral
nerve recovery processes (Sprenger-Svačina et al., 2024). The combination of transcranial photobiomodulation, orofacial myofunctional therapy, and intervention targeting laryngeal fixation patterns may have acted synergistically to facilitate functional restoration.

An important aspect of this clinical experience is the conceptualization of communication, swallowing, and mastication as functions arising from integrated neurofunctional systems rather than isolated anatomical structures. Contemporary neurophysiological models emphasize that swallowing is supported by distributed cortical, subcortical, cerebellar, and brainstem networks that operate in a highly coordinated manner (Humbert & Robbins, 2019). Therefore, interventions addressing both muscular performance and neural regulation may be particularly relevant in patients with neurological impairment.

Furthermore, the present study highlights the importance of comprehensive functional assessment in guiding therapeutic decision-making. The incorporation of technologies such as photobiomodulation, acoustic swallowing analysis, thermography, electrical stimulation, and therapeutic ultrasound should not be viewed as a substitute for clinical reasoning. Instead, these resources should be understood as complementary tools capable of enhancing diagnostic precision, treatment planning, and individualized rehabilitation strategies.

To facilitate the interpretation of the clinical findings and their relationship with the interventions performed, Table 4 summarizes the associations observed between functional impairments, therapeutic objectives, technological resources employed, and clinical outcomes."

Table 4
Relationship Between Clinical Findings, Technological Intervention, and Functional Outcomes
Note. Because of the descriptive design of this case series, findings should not be interpreted as evidence of causality. Nevertheless, they provide clinically relevant information for future controlled investigations.

Another clinically relevant finding is the potential contribution of transcranial photobiomodulation to interventions focusing on functional neural circuits. Recent literature has increasingly described the role of PBM in modulating large-scale brain networks involved in cognition, attention, motor planning, and sensory integration (Gaggi et al., 2025; Hamblin et al., 2024). Such effects may be particularly important in speech-language pathology, where communication and feeding functions depend upon the coordinated interaction of multiple cortical and subcortical systems."

Despite these promising observations, several limitations must be acknowledged. First, this study is based on a small descriptive case series, which limits the generalizability of the findings. Second, the absence of control groups and objective quantitative outcome measures prevents any conclusions regarding causality. Third, the multimodal nature of the interventions makes it difficult to determine the individual contribution of each therapeutic component.

Future research should focus on prospective controlled studies evaluating the effectiveness of photobiomodulation and other emerging technologies in speech-language pathology rehabilitation. Standardized treatment parameters, objective functional outcome measures, and larger patient samples will be necessary to establish evidence-based protocols and determine the true clinical impact of these interventions.

Table 5
Relationship Between the Main Findings of the Present Case Series and Current Scientific Evidence
Note. The proposed mechanisms are based on evidence reported in the literature and should not be interpreted as direct causal explanations for the outcomes observed in this case series.

Overall, the present cases provide preliminary clinical evidence suggesting that the integration of emerging technologies with neurofunctional and orofacial myology-based rehabilitation approaches may represent a promising avenue for the management of neurological disorders affecting communication and feeding functions. Continued investigation is warranted to further clarify the mechanisms involved and to support their incorporation into evidence-based clinical practice.
 

Conclusions
The integration of emerging technologies into speech-language pathology rehabilitation may expand therapeutic options for patients with neurological disorders affecting communication and feeding functions. In this case series, the combined use of
photobiomodulation, electrical stimulation, therapeutic ultrasound, and orofacial myology interventions was associated with improvements in swallowing, mastication, communication, and functional independence.
The findings support a neurofunctional approach in which communication and feeding are understood as the result of interactions among peripheral musculature, sensorimotor systems, and distributed neural networks. Emerging technologies may represent valuable adjunctive tools when incorporated into individualized rehabilitation programs guided by comprehensive assessment and evidence-informed clinical reasoning.
Further controlled studies with larger samples and standardized outcome measures are required to establish the effectiveness, safety, and clinical applicability of these interventions in neurological rehabilitation and speech-language pathology practice.
 

Limitations
This study presents several limitations that should be considered when interpreting the findings.
First, the report is based on a small case series involving only three patients with different neurological conditions. Consequently, the observed outcomes cannot be generalized to broader clinical populations.

Second, the absence of a control group prevents the establishment of causal relationships between the interventions and the functional improvements observed. The clinical gains reported may have been influenced by multiple factors, including spontaneous recovery, conventional rehabilitation, individual biological variability, and the interaction of different therapeutic approaches.

Third, the intervention protocol combined several treatment modalities, including transcranial photobiomodulation, targeted photobiomodulation, orofacial myofunctional therapy, electrical stimulation, and therapeutic ultrasound. Therefore, it was not possible to determine the isolated contribution of each intervention to the outcomes achieved.

Another limitation is the predominance of clinically observed outcomes. Although functional improvements were documented throughout the rehabilitation process, the incorporation of standardized quantitative measures and instrumental assessments would strengthen future investigations and improve reproducibility.

Furthermore, treatment parameters were individualized according to each patient's clinical presentation and rehabilitation goals. While this reflects real-world clinical practice, it may limit direct comparison with other studies and complicate the development of standardized intervention protocols.

Despite these limitations, the present case series provides clinically relevant observations regarding the integration of emerging technologies into speech-language pathology rehabilitation and may serve as a foundation for future controlled studies investigating the role of photobiomodulation and neurofunctional interventions in communication and swallowing disorders.
 

Ethical Considerations
This study consists of a descriptive case series developed within the context of routine speech-language pathology clinical practice. All interventions were performed in accordance with the ethical principles outlined in the Declaration of Helsinki and with applicable national and international regulations governing healthcare practice.

Patients and/or their legal representatives were informed about the therapeutic procedures, intervention objectives, and the academic use of the clinical information collected during treatment. Confidentiality was ensured through the anonymization of all patient data included in this manuscript.

The authors declare that the principles of beneficence, non-maleficence, autonomy, and justice were respected throughout the clinical care process.

Informed Consent
Written informed consent was obtained from all patients and/or their legal representatives for the therapeutic procedures described in this study and for the use of anonymized clinical information for scientific and academic publication purposes. Patient privacy and confidentiality were maintained at all stages of manuscript preparation.

Funding
This research received no specific grant from public funding agencies, commercial organizations, governmental institutions, or non-profit entities. The study was conducted using the authors' own resources.
 

Conflict of Interest Statement
The authors declare that there are no financial, academic, professional, or personal conflicts of interest that could have influenced the design of the study, data interpretation, manuscript preparation, or publication of the findings reported herein.
 

Artificial Intelligence Disclosure
Microsoft 365 Copilot was used during manuscript preparation as a support tool for language refinement, content organization, and assistance in academic writing. The authors critically reviewed, verified, edited, and approved all content generated or assisted by this tool and assume full responsibility for the scientific accuracy, interpretation of findings, conclusions, and final version of the manuscript.

Artificial intelligence did not participate in clinical decision-making, data collection, data analysis, interpretation of results, or manuscript authorship. The tool does not meet the criteria for authorship and should not be considered an author of this work.
 

Author Contributions
Nidia Patricia Cedeño Ortiz: Conceptualization, methodology development, clinical assessment supervision, therapeutic intervention design, data interpretation, manuscript drafting, scientific review, and final approval of the manuscript.
Araceli L. Peretti: Clinical intervention, methodological review, data analysis, critical revision of the manuscript, and final approval of the submitted version.

Both authors contributed substantially to the conception and development of the study and agree to be accountable for all aspects of the work.

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