The Role of Hyperbaric Oxygen Therapy in Neuroregeneration and Neuroprotection: A Review.

Neurogenesis is a high energy-demanding process, which is why blood vessels are an active part of the neurogenic niche since they allow the much-needed oxygenation of progenitor cells. In this regard, although neglected for a long time, the "oxygen niche" should be considered an important intervenient in adult neurogenesis. One possible hypothesis for the failure of numerous neuroprotective trials is that they relied on compounds that target a highly specific neuroprotective pathway. This approach may be too limited, given the complexity of the processes that lead to cell death. Therefore, research should adopt a more multifactorial approach. Among the limited range of agents with multimodal neuromodulatory capabilities, hyperbaric oxygen therapy has demonstrated effectiveness in reducing secondary brain damage in various brain injury models. This therapy functions not only as a neuroprotective mechanism but also as a powerful neuroregenerative mechanism.

Combining neuromodulation strategies in spinal cord injury gait rehabilitation: A proof of concept, randomized, crossover trial.

OBJECTIVE: To evaluate if acute intermittent hypoxia (AIH) coupled with transcutaneous spinal cord stimulation (tSCS) enhance task-specific training and lead to superior and more sustained gait improvements as compared to each of these strategies used in isolation in persons with chronic, incomplete spinal cord injury (SCI). DESIGN: Proof of concept, randomized crossover trial SETTING: Outpatient, rehabilitation hospital INTERVENTIONS: Ten participants completed 3 intervention arms: 1) AIH, tSCS, and gait training (AIH + tSCS), 2) tSCS plus gait training (SHAM AIH + tSCS), and 3) gait training alone (SHAM + SHAM). Each arm consisted of 5 consecutive days of intervention with a minimum of a 4-week washout between arms. The order of arms was randomized. The study took place from December 3, 2020 to January 4, 2023. MAIN OUTCOME MEASURES: 10-meter walk test (10MWT) at self-selected velocity (SSV) and fast velocity (FV), 6-minute walk test (6MWT), Timed Up and Go (TUG) SECONDARY OUTCOME MEASURES: Isometric ankle plantarflexion and dorsiflexion torque RESULTS: TUG improvements were 3.44 seconds (95% CI: 1.24-5.65) significantly greater in the AIH + tSCS arm than the SHAM AIH + tSCS arm at post-intervention (POST) and 3.31 seconds (95% CI: 1.03-5.58) greater than the SHAM + SHAM arm at 1-week follow up. SSV was 0.08 m/s (95% CI: 0.02-0.14) significantly greater following the AIH + tSCS arm than the SHAM AIH + tSCS at POST. Although not significant, the AIH + tSCS arm also demonstrated the greatest average improvements compared to the other two arms at POST and 1WK for the 6MWT, FV, and ankle plantarflexion torque. CONCLUSIONS: This pilot study is the first to demonstrate that combining these three neuromodulation strategies leads to superior improvements in the TUG and SSV for individuals with chronic incomplete SCI and warrants further investigation.

Repetitive transcranial magnetic stimulation promotes motor function recovery in mice after spinal cord injury via regulation of the Cx43-autophagy loop.

Spinal cord injury (SCI) is a severe condition with an extremely high disability rate. It is mainly manifested as the loss of motor, sensory and autonomic nerve functions below the injury site. High-frequency transcranial magnetic stimulation, a recently developed neuromodulation method, can increase motor function in mice with spinal cord injury. This study aimed to explore the possible mechanism by which transcranial magnetic stimulation (TMS) restores motor function after SCI. A complete T8 transection model of the spinal cord was established in mice, and the mice were treated daily with 15 Hz high-frequency transcranial magnetic stimulation. The BMS was used to evaluate the motor function of the mice after SCI. Western blotting and immunofluorescence were used to detect the expression of Connexin43 (CX43) and autophagy-related proteins in vivo and in vitro, and correlation analysis was performed to study the relationships among autophagy, CX43 and motor function recovery after SCI in mice. Western blotting was used to observe the effect of magnetic stimulation on the expression of mTOR pathway members. In the control group, the expression of CX43 was significantly decreased, and the expression of microtubule-associated protein 1 A/1b light chain 3 (LC3II) and P62 was significantly increased after 4 weeks of spinal cord transection. After high-frequency magnetic stimulation, the level of CX43 decreased, and the levels of LC3II and P62 increased in primary astrocytes. The BMS of the magnetic stimulation group was greater than that of the control group. High-frequency magnetic stimulation can inhibit the expression of CX43, which negatively regulates autophagic flux. HF-rTMS increased the expression levels of mTOR, p-mTOR and p-S6. Our experiments showed that rTMS can restore hindlimb motor function in mice after spinal cord injury via regulation of the Cx43-autophagy loop and activation of the mTOR signalling pathway.

The comparison of DBS and RNS for adult drug-resistant epilepsy: a systematic review and meta-analysis.

Objective: Neuromodulation has been proven to be a promising alternative treatment for adult patients with drug-resistant epilepsy (DRE). Deep brain stimulation (DBS) and responsive neurostimulation (RNS) were approved by many countries for the treatment of DRE. However, there is a lack of systematic studies illustrating the differences between them. This meta-analysis is performed to assess the efficacy and clinical characteristics of DBS and RNS in adult patients with DRE. Methods: PubMed, Web of Science, and Embase were retrieved to obtain related studies including adult DRE patients who accepted DBS or RNS. The clinical characteristics of these patients were compiled for the following statistical analysis. Results: A total of 55 studies (32 of DBS and 23 of RNS) involving 1,568 adult patients with DRE were included in this meta-analysis. There was no significant difference in seizure reduction and responder rate between DBS and RNS for DRE. The seizure reduction of DBS and RNS were 56% (95% CI 50-62%, p > 0.05) and 61% (95% CI 54-68%, p > 0.05). The responder rate of DBS and RNS were 67% (95% CI 58-76%, p > 0.05) and 71% (95% CI 64-78%, p > 0.05). Different targets of DBS did not show significant effect on seizure reduction (p > 0.05). Patients with DRE who accepted DBS were younger than those of RNS (32.9 years old vs. 37.8 years old, p < 0.01). The mean follow-up time was 47.3 months for DBS and 39.5 months for RNS (p > 0.05). Conclusion: Both DBS and RNS are beneficial and alternative therapies for adult DRE patients who are not eligible to accept resection surgery. Further and larger studies are needed to clarify the characteristics of different targets and provide tailored treatment for patients with DRE.

Current state of clinical ultrasound neuromodulation.

Unmatched by other non-invasive brain stimulation techniques, transcranial ultrasound (TUS) offers highly focal stimulation not only on the cortical surface but also in deep brain structures. These unique attributes are invaluable in both basic and clinical research and might open new avenues for treating neurological and psychiatric diseases. Here, we provide a concise overview of the expanding volume of clinical investigations in recent years and upcoming research initiatives concerning focused ultrasound neuromodulation. Currently, clinical TUS research addresses a variety of neuropsychiatric conditions, such as pain, dementia, movement disorders, psychiatric conditions, epilepsy, disorders of consciousness, and developmental disorders. As demonstrated in sham-controlled randomized studies, TUS neuromodulation improved cognitive functions and mood, and alleviated symptoms in schizophrenia and autism. Further, preliminary uncontrolled evidence suggests relieved anxiety, enhanced motor functions in movement disorders, reduced epileptic seizure frequency, improved responsiveness in patients with minimally conscious state, as well as pain reduction after neuromodulatory TUS. While constrained by the relatively modest number of investigations, primarily consisting of uncontrolled feasibility trials with small sample sizes, TUS holds encouraging prospects for treating neuropsychiatric disorders. Larger sham-controlled randomized trials, alongside further basic research into the mechanisms of action and optimal sonication parameters, are inevitably needed to unfold the full potential of TUS neuromodulation.

Transcranial Direct Current Stimulation for Food Craving in Women Affected by Overweight and Obesity: A Randomized Controlled Trial.

INTRODUCTION: Craving is a multifactorial behavior caused by central circuit imbalance. The proposed treatments involve exercise and reduced food intake. However, the treatments frequently fail. This study aimed to investigate the effect of 10 consecutive sessions of anodal transcranial direct current stimulation over the right dorsolateral prefrontal cortex on food craving and eating consumption of women affected by overweight and obesity. METHODS: A randomized double-blind controlled trial with 50 volunteers was divided into two groups (active-tDCS: n = 25 and sham-tDCS: n = 25). There were a total of 10 consecutive tDCS sessions (2 mA, for 20 min) with an F4 anodal-F3 cathodal montage. We evaluated the effects on eating behavior (food craving, uncontrolled eating, emotional eating, and cognitive restriction), food consumption (calories and macronutrients), and anthropometric and body composition variables (weight, body mass index, waist circumference, and body fat percentage). RESULTS: There were no statistically significant results between groups at the baseline regarding sociodemographic and clinical characteristics. Also, there was no significant interaction between time versus group for any of the variables studied. Treatment with tDCS was well tolerated and there were no serious adverse effects. CONCLUSIONS: In women affected by overweight and obesity with food cravings, 10 sessions of F4 (anodal) and F3 (cathodal) tDCS did not produce changes in eating behavior, food consumption, and anthropometric and body composition.

Surgical outcomes of patients with genetically refractory epilepsy: A systematic review and meta-analysis.

OBJECTIVE: To summarize the surgical outcomes of genetically refractory epilepsy and identify prognostic factors for these outcomes. METHODS: A literature search of the PubMed, Web of Science, and Embase databases for relevant studies, published between January 1, 2002 and December 31, 2023, was performed using specific search terms. All studies addressing surgical outcomes and follow-up of genetically refractory epilepsy were included. All statistical analyses were performed using STATA software (StataCorp LLC, College Station, TX, USA). This review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, 2020 (i.e., "PRISMA") reporting guidelines. RESULTS: Of the 3833 studies retrieved, 55 fulfilled the inclusion criteria. Eight studies were eligible for meta-analysis at the study level. Pooled outcomes revealed that 74 % of patients who underwent resective surgery (95 % confidence interval [CI] 0.55-0.89; z = 9.47, p < 0.05) achieved Engel I status at the last follow-up. In the study level analysis, pooled outcomes revealed that 9 % of patients who underwent vagus nerve stimulation achieved seizure-free status (95 % CI 0.00-0.31; z = 1.74, p < 0.05), and 61 % (95 % CI 0.55-0.89; z = 11.96, p < 0.05) achieved a 50 % reduction in seizure frequency at the last follow-up. Fifty-three studies comprising 249 patients were included in an individual-level analysis. Among patients who underwent lesion resection or lobectomy/multilobar resection, 65 % (100/153) achieved Engel I status at the last follow-up. Univariate analysis indicated that female sex, somatic mutations, and presenting with focal seizure symptoms were associated with better prognosis (p < 0.05). Additionally, 75 % (21/28) of patients who underwent hemispherectomy/hemispherotomy achieved Engel I status at the last follow-up. In the individual-level analysis, among patients treated with vagus nerve stimulation, 21 % (10/47) were seizure-free and 64 % (30/47) experienced >50 % reduction in seizure frequency compared with baseline. CONCLUSION: Meticulous presurgical evaluation and selection of appropriate surgical procedures can, to a certain extent, effectively control seizures. Therefore, various surgical procedures should be considered when treating patients with genetically refractory epilepsy.

Neurosurgical therapy possibilities in treatment of Huntington disease: An update.

INTRODUCTION: Huntington's disease (HD) is a hereditary condition caused by the expansion of the CAG trinucleotide in the huntingtin gene on chromosome 4, resulting in motor, cognitive, and psychiatric disorders that significantly impact patients' quality of life. Despite the lack of effective treatments for the disease, various surgical strategies have been explored to alleviate symptoms and slow its progression. METHODOLOGY: A comprehensive systematic literature review was conducted, including MeSH terms, yielding only 38 articles that were categorized based on the surgical procedure. The study aimed to describe the types of surgeries performed and their efficacy in HD patients. RESULTS: Deep brain stimulation (DBS) involved 41 predominantly male patients with bilateral implantation in the globus pallidus, showing a preoperative Unified Huntington's Disease Rating Scale (UHDRS) score of 60.25 ± 16.13 and a marked postoperative value of 48.54 ± 13.93 with a p < 0.018 at one year and p < 0.040 at three years. Patients experienced improvement in hyperkinesia but worsening of bradykinesia. Additionally, cell transplantation in 119 patients resulted in a lower preoperative UHDRS score of 34.61 ± 14.61 and a significant postoperative difference of 32.93 ± 15.87 (p < 0.016), respectively, in the first to third years of following. Some now, less used procedures were crucial for understanding brain function, such as pallidotomies in 3 patients, showing only a 25 % difference from their baseline. CONCLUSION: Despite advancements in technology, there is still no curative treatment, only palliative options. Promising treatments like trophic factor implantation offer new prospects for the future.

Functional nanotransducer-mediated wireless neural modulation techniques.

Functional nanomaterials have emerged as versatile nanotransducers for wireless neural modulation because of their minimal invasion and high spatiotemporal resolution. The nanotransducers can convert external excitation sources (e.g., NIR light, X-rays, and magnetic fields) to visible light (or local heat) to activate optogenetic opsins and thermosensitive ion channels for neuromodulation. The present review provides insights into the fundamentals of the mostly used functional nanomaterials in wireless neuromodulation including upconversion nanoparticles, nanoscintillators, and magnetic nanoparticles. We further discussed the recent developments in design strategies of functional nanomaterials with enhanced energy conversion performance that have greatly expanded the field of neuromodulation. We summarized the applications of functional nanomaterials-mediated wireless neuromodulation techniques, including exciting/silencing neurons, modulating brain activity, controlling motor behaviors, and regulating peripheral organ function in mice. Finally, we discussed some key considerations in functional nanotransducer-mediated wireless neuromodulation along with the current challenges and future directions.

Effects of high-definition transcranial direct current stimulation combined with inspiratory muscle training for treating respiratory sequelae of long COVID: A case series.

INTRODUCTION: Long COVID occurs when numerous symptoms begin 3 weeks after acute infection and last for 12 months or more. High-definition transcranial direct current stimulation (HD-tDCS) has been tested in patients with COVID-19; however, previous studies did not investigate the HD-tDCS use combined with inspiratory muscle training (IMT) for respiratory sequelae of long COVID. CASE PRESENTATION: Six individuals (four women and two men) aged between 29 and 71 years and presenting with respiratory sequelae of long COVID were included. They were submitted to an intervention that comprised HD-tDCS combined with IMT twice a week for 5 weeks. Lung function and respiratory muscle assessments were performed at baseline and after 5 weeks of intervention. IMPLICATIONS ON PHYSIOTHERAPY PRACTICE: HD-tDCS may enhance the IMT effects by increasing respiratory muscle strength, efficiency, and lung function of individuals with long COVID.

Scalp acupuncture guidance for identifying the optimal site for transcranial electrical stimulation of the hand.

Transcranial electrical stimulation (tES) often targets the EEG-guided C3/C4 area that may not accurately represent M1 for hand muscles. This study aimed to determine if the neuroanatomy-based scalp acupuncture-guided site (AC) was a more effective spot than the C3 site for neuromodulation. Fifteen healthy subjects received one 20-minute session of high-definition transcranial alternating current stimulation (HD-tACS) intervention (20 Hz at 2 mA) at the AC or C3 sites randomly with a 1-week washout period. Subjects performed ball-squeezing exercises with the dominant hand during the HD-tACS intervention. The AC site was indiscernible from the finger flexor hotspot detected by TMS. At the baseline, the MEP amplitude from finger flexors was greater with less variability at the AC site than at the C3 site. HD-tACS intervention at the AC site significantly increased the MEP amplitude. However, no significant changes were observed after tACS was applied to the C3 site. Our results provide evidence that HD-tACS at the AC site produces better neuromodulation effects on the flexor digitorum superficialis (FDS) muscle compared to the C3 site. The AC localization approach can be used for future tES studies.

Dopamine and deep brain stimulation accelerate the neural dynamics of volitional action in Parkinson's disease.

The ability to initiate volitional action is fundamental to human behaviour. Loss of dopaminergic neurons in Parkinson's disease is associated with impaired action initiation, also termed akinesia. Both dopamine and subthalamic deep brain stimulation (DBS) can alleviate akinesia, but the underlying mechanisms are unknown. An important question is whether dopamine and DBS facilitate de novo build-up of neural dynamics for motor execution or accelerate existing cortical movement initiation signals through shared modulatory circuit effects. Answering these questions can provide the foundation for new closed-loop neurotherapies with adaptive DBS, but the objectification of neural processing delays prior to performance of volitional action remains a significant challenge. To overcome this challenge, we studied readiness potentials and trained brain signal decoders on invasive neurophysiology signals in 25 DBS patients (12 female) with Parkinson's disease during performance of self-initiated movements. Combined sensorimotor cortex electrocorticography (ECoG) and subthalamic local field potential (LFP) recordings were performed OFF therapy (N = 22), ON dopaminergic medication (N = 18) and ON subthalamic deep brain stimulation (N = 8). This allowed us to compare their therapeutic effects on neural latencies between the earliest cortical representation of movement intention as decoded by linear discriminant analysis classifiers and onset of muscle activation recorded with electromyography (EMG). In the hypodopaminergic OFF state, we observed long latencies between motor intention and motor execution for readiness potentials and machine learning classifications. Both, dopamine and DBS significantly shortened these latencies, hinting towards a shared therapeutic mechanism for alleviation of akinesia. To investigate this further, we analysed directional cortico-subthalamic oscillatory communication with multivariate granger causality. Strikingly, we found that both therapies independently shifted cortico-subthalamic oscillatory information flow from antikinetic beta (13-35 Hz) to prokinetic theta (4-10 Hz) rhythms, which was correlated with latencies in motor execution. Our study reveals a shared brain network modulation pattern of dopamine and DBS that may underlie the acceleration of neural dynamics for augmentation of movement initiation in Parkinson's disease. Instead of producing or increasing preparatory brain signals, both therapies modulate oscillatory communication. These insights provide a link between the pathophysiology of akinesia and its' therapeutic alleviation with oscillatory network changes in other non-motor and motor domains, e.g. related to hyperkinesia or effort and reward perception. In the future, our study may inspire the development of clinical brain computer interfaces based on brain signal decoders to provide temporally precise support for action initiation in patients with brain disorders.

Long-term outcomes of sacral neuromodulation for low anterior resection syndrome after rectal cancer surgery.

PURPOSE: This study assessed the long-term outcomes and quality of life in patients who underwent sacral neuromodulation (SNM) due to low anterior resection syndrome (LARS). METHODS: This single-center retrospective study, conducted from 2005 to 2021, included 30 patients (21 men; median age, 70 years) who had undergone total mesorectal excision with stoma closure and had no recurrence at inclusion. All patients were diagnosed with LARS refractory to conservative treatment. We evaluated clinical and quality-of-life outcomes after SNM through a stool diary, Wexner score, LARS score, the Fecal Incontinence Quality of Life (FIQL) questionnaire, and EuroQol-5D (EQ-5D) questionnaire. RESULTS: Peripheral nerve stimulation was successful in all but one patient. Of the 29 patients who underwent percutaneous nerve evaluation, 17 (58.62%) responded well to SNM and received permanent implants. The median follow-up period was 48 months (range, 18-153 months). The number of days per week with fecal incontinence episodes decreased from a median of 7 (range, 2-7) to 0.38 (range, 0-1). The median number of bowel movements recorded in patient diaries fell from 5 (range, 4-12) to 2 (range, 1-6). The median Wexner score decreased from 18 (range, 13-20) to 6 (range, 0-16), while the LARS score declined from 38.5 (range, 37-42) to 19 (range, 4-28). The FIQL and EQ-5D questionnaires demonstrated enhanced quality of life. CONCLUSION: SNM may benefit patients diagnosed with LARS following rectal cancer surgery when conservative options have failed, and the treatment outcomes may possess long-term sustainability.

Brain-machine interactive neuromodulation research tool with edge AI computing.

Closed-loop neuromodulation with intelligence methods has shown great potentials in providing novel neuro-technology for treating neurological and psychiatric diseases. Development of brain-machine interactive neuromodulation strategies could lead to breakthroughs in precision and personalized electronic medicine. The neuromodulation research tool integrating artificial intelligent computing and performing neural sensing and stimulation in real-time could accelerate the development of closed-loop neuromodulation strategies and translational research into clinical application. In this study, we developed a brain-machine interactive neuromodulation research tool (BMINT), which has capabilities of neurophysiological signals sensing, computing with mainstream machine learning algorithms and delivering electrical stimulation pulse by pulse in real-time. The BMINT research tool achieved system time delay under 3 ms, and computing capabilities in feasible computation cost, efficient deployment of machine learning algorithms and acceleration process. Intelligent computing framework embedded in the BMINT enable real-time closed-loop neuromodulation developed with mainstream AI ecosystem resources. The BMINT could provide timely contribution to accelerate the translational research of intelligent neuromodulation by integrating neural sensing, edge AI computing and stimulation with AI ecosystems.

Lumbar Sympathetic Block Leading to Increased Arterial Diameter and Blood Flow: A Mechanism of Therapeutic Benefit.

Lumbar sympathetic blocks (LSBs) have long been used for the treatment of chronic lower extremity pain and for conditions such as complex regional pain syndrome (CRPS). With a better understanding of the autonomic nervous system and its function, these blocks have grown in their utility. Through this growth, however, our understanding of sympathetic-mediated pain is still vaguely understood. Here, we present a case of a patient who underwent a point-of-care ultrasound (POCUS) before and after an LSB, and we were able to show significant dilation of the posterior tibial artery (PTA) following the block. We propose that this arterial dilation plays a mechanistic role in providing pain relief to patients who undergo LSB. This increased blood flow can not only enhance healing properties to surrounding tissues but also allow for nitric oxide to play potential regulatory roles in pain pathways. Here, we also review potential mechanisms of the amelioration of sympathetic-mediated pain as well as the potential utilization of LSBs and neuromodulation in treating visceral pathologies through a better understanding of visceral somatic relationships.

Identifying SCS Trial Responders Immediately After Postoperative Programming with ECAP Dose-Controlled Closed-Loop Therapy.

INTRODUCTION: Drawbacks of fixed-output spinal cord stimulation (SCS) screening trials may lead to compromised trial outcomes and poor predictability of long-term success. Evoked compound action potential (ECAP) dose-controlled closed-loop (CL) SCS allows objective confirmation of therapeutic neural activation and pulse-to-pulse stimulation adjustment. We report on the immediate patient-reported and neurophysiologic treatment response post-physiologic CL-SCS and feasibility of early SCS trial responder prediction. METHODS: Patient-reported pain relief, functional improvement, and willingness to proceed to permanent implant were compared between the day of the trial procedure (Day 0) and end of trial (EOT) for 132 participants in the ECAP Study undergoing a trial stimulation period. ECAP-based neurophysiologic measurements from Day 0 and EOT were compared between responder groups. RESULTS: A high positive predictive value (PPV) was achieved with 98.4% (60/61) of patients successful on the Day 0 evaluation also responding at EOT. The false-positive rate (FPR) was 5.6% (1/18). ECAP-based neurophysiologic measures were not different between patients who passed all Day 0 success criteria ("Day 0 successes") and those who did not ("needed longer to evaluate the therapy"). However, at EOT, responders had higher therapeutic usage and dose levels compared to non-responders. CONCLUSIONS: The high PPV and low FPR of the Day 0 evaluation provide confidence in predicting trial outcomes as early as the day of the procedure. Day 0 trials may be beneficial for reducing patient burden and complication rates associated with extended trials. ECAP dose-controlled CL-SCS therapy may provide objective data and rapid-onset pain relief to improve prognostic ability of SCS trials in predicting outcomes. TRIAL REGISTRATION: The ECAP Study is registered with ClinicalTrials.gov (NCT04319887).

A Visual and Narrative Timeline Review of Spinal Cord Stimulation Technology and US Food and Drug Administration Milestones.

OBJECTIVES: The aim of this study was to present key technologic and regulatory milestones in spinal cord stimulation (SCS) for managing chronic pain on a narrative timeline with visual representation, relying on original sources to the extent possible. MATERIALS AND METHODS: We identified technical advances in SCS that facilitated and enhanced treatment on the basis of scientific publications and approvals from the United States (US) Food and Drug Administration (FDA). We presented milestones limited to first use in key indications and in the context of new technology validation. We focused primarily on pain management, but other indications (eg, motor disorder in multiple sclerosis) were included when they affected technology development. RESULTS: We developed a comprehensive visual and narrative timeline of SCS technology and US FDA milestones. Since its conception in the 1960s, the science and technology of SCS neuromodulation have continuously evolved. Advances span lead design (from paddle-type to percutaneous, and increased electrode contacts) and stimulator technology (from wireless power to internally powered and rechargeable, with miniaturized components, and programmable multichannel devices), with expanding stimulation program flexibility (such as burst and kilohertz stimulation frequencies), as well as usage features (such as remote programming and magnetic resonance imaging conditional compatibility). CONCLUSIONS: This timeline represents the evolution of SCS technology alongside expanding FDA-approved indications for use.

HD-tDCS to the lateral occipital complex improves haptic object recognition.

High-definition transcranial direct current stimulation (HD-tDCS) is a non-invasive brain stimulation technique that has been shown to be safe and effective in modulating neuronal activity. The present study investigates the effect of anodal HD-tDCS on haptic object perception and memory through stimulation of the lateral occipital complex (LOC), a structure that has been shown to be involved in both visual and haptic object recognition. In this single-blind, sham-controlled, between-subjects study, blindfolded healthy, sighted participants used their right (dominant) hand to perform haptic discrimination and recognition tasks with 3D-printed, novel objects called "Greebles" while receiving 20 min of 2 milliamp (mA) anodal stimulation (or sham) to the left or right LOC. Compared to sham, those who received left LOC stimulation (contralateral to the hand used) showed an improvement in haptic object recognition but not discrimination-a finding that was evident from the start of the behavioral tasks. A second experiment showed that this effect was not observed with right LOC stimulation (ipsilateral to the hand used). These results suggest that HD-tDCS to the left LOC can improve recognition of objects perceived via touch. Overall, this work sheds light on the LOC as a multimodal structure that plays a key role in object recognition in both the visual and haptic modalities.