Reduced tactile acuity in chronic low back pain is linked with structural neuroplasticity in primary somatosensory cortex and is modulated by acupuncture therapy.

Prior studies have shown that patients suffering from chronic Low Back Pain (cLBP) have impaired somatosensory processing including reduced tactile acuity, i.e. reduced ability to resolve fine spatial details with the perception of touch. The central mechanism(s) underlying reduced tactile acuity are unknown but may include changes in specific brain circuitries (e.g. neuroplasticity in the primary somatosensory cortex, S1). Furthermore, little is known about the linkage between changes in tactile acuity and the amelioration of cLBP by somatically-directed therapeutic interventions, such as acupuncture. In this longitudinal neuroimaging study, we evaluated healthy control adults (HC, N â€‹= â€‹50) and a large sample of cLBP patients (N â€‹= â€‹102) with structural brain imaging (T1-weighted MRI for Voxel-Based Morphometry, VBM; Diffusion Tensor Imaging, DTI) and tactile acuity testing using two-point discrimination threshold (2PDT) over the lower back (site of pain) and finger (control) locations. Patients were evaluated at baseline and following a 4-week course of acupuncture, with patients randomized to either verum acupuncture, two different forms of sham acupuncture (designed with or without somatosensory afference), or no-intervention usual care control. At baseline, cLBP patients demonstrated reduced acuity (greater 2PDT, P â€‹= â€‹0.01) over the low back, but not finger (P â€‹= â€‹0.29) locations compared to HC, suggesting that chronic pain affects tactile acuity specifically at body regions encoding the experience of clinical pain. At baseline, Gray Matter Volume (GMV) was elevated and Fractional Anisotropy (FA) was reduced, respectively, in the S1-back region of cLBP patients compared to controls (P â€‹< â€‹0.05). GMV in cLBP correlated with greater 2PDT-back scores (ρ â€‹= â€‹0.27, P â€‹= â€‹0.02). Following verum acupuncture, tactile acuity over the back was improved (reduced 2PDT) and greater improvements were associated with reduced S1-back GMV (ρ â€‹= â€‹0.52, P â€‹= â€‹0.03) and increased S1-back adjacent white matter FA (ρ â€‹= â€‹-0.56, P â€‹= â€‹0.01). These associations were not seen for non-verum control interventions. Thus, S1 neuroplasticity in cLBP is linked with deficits in tactile acuity and, following acupuncture therapy, may represent early mechanistic changes in somatosensory processing that track with improved tactile acuity.

Effects of an antiadhesive agent on functional recovery of the greater auricular nerve after parotidectomy: a double-blind randomized controlled trial.

PURPOSE: Periauricular sensory deficit occurs frequently after parotidectomy even in cases with preservation of the greater auricular nerve (GAN). This study was performed to evaluate the effects of antiadhesive agent in functional recovery of the GAN after parotidectomy. METHODS: Ninety-eight patients undergoing partial parotidectomy for benign parotid tumors were prospectively enrolled in this multicenter, double-blind randomized controlled study and randomly assigned to either the study or control group. Antiadhesive agent was applied in the study group. The results of sensory tests (tactile, heat, and cold sensitivity) and a questionnaire on quality of life (QoL) were acquired at postoperative 1, 8, and 24 weeks after surgery. Clinical parameters, and the results of the sensory tests and the questionnaire, were compared between the two groups. RESULTS: A total of 80 patients were finally enrolled. On sensory evaluation, tactile sensation and warm sensation in the ear lobule, and warm sensation in the mastoid area, showed significant improvement at 24 weeks postoperatively in the study group. There were no significant differences between the two groups on any questions in the QoL questionnaire, at any follow-up time point. CONCLUSIONS: Antiadhesive agents have some positive effects on functional recovery of the GAN after parotidectomy. Therefore, applying antiadhesive agents after parotidectomy can reduce discomfort in patients.

Visual agnosia and focal brain injury.

Visual agnosia encompasses all disorders of visual recognition within a selective visual modality not due to an impairment of elementary visual processing or other cognitive deficit. Based on a sequential dichotomy between the perceptual and memory systems, two different categories of visual object agnosia are usually considered: 'apperceptive agnosia' and 'associative agnosia'. Impaired visual recognition within a single category of stimuli is also reported in: (i) visual object agnosia of the ventral pathway, such as prosopagnosia (for faces), pure alexia (for words), or topographagnosia (for landmarks); (ii) visual spatial agnosia of the dorsal pathway, such as cerebral akinetopsia (for movement), or orientation agnosia (for the placement of objects in space). Focal brain injuries provide a unique opportunity to better understand regional brain function, particularly with the use of effective statistical approaches such as voxel-based lesion-symptom mapping (VLSM). The aim of the present work was twofold: (i) to review the various agnosia categories according to the traditional visual dual-pathway model; and (ii) to better assess the anatomical network underlying visual recognition through lesion-mapping studies correlating neuroanatomical and clinical outcomes.

[Geriatric psychiatric home counseling for people with dementia and anosognosia : Results of a model project]. / Gerontopsychiatrische Hausbesuche bei Menschen mit Demenz und Anosognosie : Ergebnisse eines Modellprojekts.

BACKGROUND: Lack of awareness of an illness (anosognosia) is a common symptom in dementia and has a significant impact on the course of the disease. It is associated with dysfunctional interaction with caregivers. Due to unawareness patients are not able to accept diagnostic procedures or medical treatment and refuse any kind of support. Thus, they are not integrated into psychosocial networks and medical support. This has a significant impact on patient-centered care in a domestic environment. In this article a model project with home visits to patients with dementia and anosognosia is described. METHOD: A total of 55 home visits were carried out. The aim of this project was the integration into the existing healthcare services in order to safeguard the domestic environment. These visits focused on advice and information for the patients and their caregivers initiating the visits. Sociodemographic data of the patient cohort and the satisfaction of the caregiving relatives and general practitioners are presented. RESULTS: Subjects with dementia were found to be in advanced stages of the disease, caring situations were complex and required assistance. Caregivers showed a substantial burden in accordance with previous reports. CONCLUSION: New strategies are required to cope with anosognosia in patients with dementia and their caregivers. Even single home visits seem to be sufficient to initiate support for subjects with dementia and their relatives.

Olfactory functions scale with circuit restoration in a rapidly reversible Alzheimer's disease model.

Neural circuits maintain a precise organization that is vital for normal brain functions and behaviors, but become disrupted during neurological disease. Understanding the connection between wiring accuracy and function to measure disease progression or recovery has been difficult because of the complexity of behavioral circuits. The olfactory system maintains well-defined neural connections that regenerate throughout life. We previously established a reversible in vivo model of Alzheimer's disease by overexpressing a humanized mutated amyloid precursor protein (hAPP) in olfactory sensory neurons (OSNs). Using this model, we currently show that hAPP is present in the OSN axons of mutant mice, which exhibit strong caspase3 signal and reduced synaptic protein expression by 3 weeks of age. In the olfactory bulb, we show that glomerular structure is distorted and OSN axonal convergence is lost. In vivo functional imaging experiments further demonstrate disruption of the glomerular circuitry, and behavioral assays reveal that olfactory function is significantly impaired. Because OSNs regenerate, we also tested if the system could recover from hAPP-induced disruption. We found that after 1 or 3 weeks of shutting-off hAPP expression, the glomerular circuit was partially restored both anatomically and functionally, with behavioral deficits similarly reversed. Interestingly, the degree of functional recovery tracked directly with circuit restoration. Together, these data demonstrate that hAPP-induced circuit disruption and subsequent recovery can occur rapidly and that behavior can provide a measure of circuit organization. Thus, olfaction may serve as a useful biomarker to both follow disease progression and gauge potential recovery.

Effect of high- and low-frequency repetitive transcranial magnetic stimulation on visuospatial neglect in patients with acute stroke: a double-blind, sham-controlled trial.

OBJECTIVE: To compare the therapeutic effect of low- and high-frequency repetitive transcranial magnetic stimulation (rTMS) of the posterior parietal cortex (PPC) in patients with acute stroke with visuospatial neglect. DESIGN: This study was a prospective, double-blind, sham-controlled trial. Data are presented from 27 patients (15 men, 12 women; mean age, 67.0y) randomly assigned to receive 10 sessions of low-frequency (1Hz) rTMS over the nonlesioned PPC, high-frequency (10Hz) rTMS over the lesioned PPC, or sham stimulation. SETTING: National university hospital. PARTICIPANTS: Patients (N=27) diagnosed with visuospatial neglect after stroke. INTERVENTION: Ten sessions of rTMS over a 2-week period. MAIN OUTCOME MEASURES: The severity of visuospatial neglect was assessed pre- and posttreatment using the Motor-Free Visual Perception Test, line bisection test, star cancellation test, and Catherine Bergego Scale. RESULTS: When comparing the differences in the Motor-Free Visual Perception Test, line bisection test, star cancellation test, Catherine Bergego Scale, and Korean-Modified Barthel Index (K-MBI) scores before and after treatment according to group, we found that changes in the line bisection test and K-MBI scores were significantly different between 3 groups. In the post hoc analysis, the improvement in the line bisection test score in the high-frequency rTMS group was statistically significant compared with that in the sham stimulation group (high vs sham P=.03, low vs sham P=.09, high vs low P=.58), and the improvements in the K-MBI scores of the 2 rTMS groups were statistically significant compared with those in the sham stimulation group (high vs sham P<.01, low vs sham P=.02, high vs low P=.75). CONCLUSIONS: These results indicate that high-frequency rTMS is effective in the treatment of visuospatial neglect in patients with acute stroke.

Mirror agnosia and the mirrored-self misidentification delusion: a hypnotic analogue.

INTRODUCTION: Mirrored-self misidentification is the delusional belief that one's reflection in the mirror is a stranger. Current theories suggest that one pathway to the delusion is mirror agnosia (a deficit in which patients are unable to use mirror knowledge when interacting with mirrors). This study examined whether a hypnotic suggestion for mirror agnosia can recreate features of the delusion. METHOD: Ten high hypnotisable participants were given either a suggestion to not understand mirrors or to see the mirror as a window. Participants were asked to look into a mirror and describe what they saw. Participants were tested on their understanding of mirrors and received a series of challenges. Participants then received a detailed postexperimental inquiry. RESULTS: Three of five participants given the suggestion to not understand mirrors reported seeing a stranger and maintained this belief when challenged. These participants also showed signs of mirror agnosia. No participants given the suggestion to see a window reported seeing a stranger. CONCLUSION: Results indicate that a hypnotic suggestion for mirror agnosia can be used to recreate the mirrored-self misidentification delusion. Factors influencing the effectiveness of hypnotic analogues of psychopathology, such as participants' expectations and interpretations, are discussed.

Anosognosia and neglect respond differently to the same treatments.

Different techniques, such as optokinetic stimulation, adaptation to prismatic shift of the visual field to the right, or transcutaneous electrical nerve stimulation (TENS), have been shown to alleviate neglect, at least temporarily. We assessed the effect of these techniques on anosognosia and whether their therapeutic effect, if any, matches that on neglect. The effect of the three types of treatment on anosognosia and neglect was investigated in five patients presenting with both severe anosognosia and neglect. Patient 1 was treatment responsive to anosognosia but not to neglect, whereas patients 4 and 5 showed the reverse pattern, i.e., they were treatment responsive to neglect but not to anosognosia. This "treatment response bias" proved to be a valid means to investigate different effects of treatments in the same patient.

Perceptual post-effects of left neck muscle vibration with visuo-haptic feedback in healthy individuals: A potential approach for treating spatial neglect.

Among the techniques used to reduce spatial neglect's symptoms, left neck muscle vibration (NMV) is alluring because it does not require the patient's attentional co-operation. The aim of this study was to determine the type of NMV-associated feedback that induced the most intense and longest-lasting egocentric post-effects. Eighty-seven healthy individuals were randomly assigned to four intervention groups: "neck muscle vibration, blindfolded" (NMV), "neck muscle vibration with vision" (NMV + V), "neck muscle vibration and visual finger-pointing" (NMV + P), and "visual finger-pointing" (P). An eyes-closed finger-pointing subjective straight-ahead (SSA) test was carried out before the intervention, immediately afterwards, and 30 min afterwards. The results showed that only the NMV + P intervention induced a lasting leftward bias of SSA. In addition, the deviation reported in this intervention group differed significantly from those observed in the other interventions. The combination of visuo-haptic feedback and neck-somatosensory stimulation may enable a full, lasting intermodal recalibration, which could be potentiated by the attention level engaged during voluntary pointing. These outcomes highlighted that the NMV technique could easily integrate into routine occupational therapy sessions for treating various aspects of neglect disorders.

Anosognosia: clinical and ethical considerations.

PURPOSE OF REVIEW: This review considers recent findings on classical forms of anosognosia and less dramatic disturbances in self-awareness observed in various brain disorders. It also addresses issues of clinical management and ethical treatment. RECENT FINDINGS: The study of anosognosia for hemiplegia, Anton's syndrome, and less dramatic disturbances in self-awareness in conditions such as Alzheimer's disease, mild cognitive impairment, and severe traumatic brain injury suggests its 'multifactorial' nature. Lesions in various regions of the brain may contribute to different forms of anosognosia. Animal and human studies suggest that the insular cortex plays an important role in subjective awareness of feeling states, and may be implicated in various forms of anosognosia. Also, right frontal lobe lesions have been implicated, but typically in patients who have bilateral cerebral dysfunction. These patients require careful clinical management in light of their reduced awareness of their neurological and neuropsychological functions that impact daily activities. SUMMARY: The study of anosognosia and disorders of self-awareness has expanded greatly over the past 20 years. Various patient groups may show different levels of impaired awareness or anosognosia. Guidelines for the clinical management and ethical treatment of these patients are needed, but beginning efforts have been made.

Self-observation reinstates motor awareness in anosognosia for hemiplegia.

We report a patient with severe anosognosia for hemiplegia, who recovered instantly and permanently when viewing herself in a video replay. We believe the observed dramatic reinstatement of the patient's awareness related to her self-observation 'from the outside' (3rd person perspective) and 'off-line' (at a time later than the actual attempt to execute a movement); her anosognosia had been unaltered when she observed her plegic arm in her ipsilateral visual field (self-observation from a 1st-person perspective and 'on-line'). To our knowledge, the role of self-observation in videos or mirrors has not being assessed in AHP to date. Our study provides preliminary evidence that, when right hemisphere damage impairs the ability to update one's body representation, judgements relying on 3rd-person and off-line self-observation may be spared in some patients and may facilitate 1st person awareness.

The effect of olfactory training on odor identification in patients with traumatic anosmia.

BACKGROUND: This study investigates the effect of olfactory training on odor identification in patients with traumatic anosmia. METHODS: Patients with a clear history of loss of smell after head injury, and whose phenyl ethyl alcohol (PEA) odor detection thresholds remained at -1 after steroid and zinc treatment, were included in this study between July 2016 and July 2018. They were randomly divided into 2 groups, with patients in the 4-odorant group given 4 bottles of PEA, lemon, eucalyptus, and clove oils and those in the PEA group given a bottle of PEA for 6-month olfactory training. After 3-month and 6-month training, the olfactory function was evaluated by both the PEA threshold test and the traditional Chinese version of the University of Pennsylvania Smell Identification Test (UPSIT-TC). Magnetic resonance imaging was performed to measure the volume of olfactory bulbs after training. RESULTS: There were 45 patients completing 4-odorant training and another 45 completing PEA training. The birhinal PEA threshold decreased significantly in both groups after 6-month training, but the decrease was not significantly different between the 2 groups. The UPSIT-TC score increased significantly in the PEA group but not in the 4-odorant group. The volume of olfactory bulbs was not significantly different between these 2 groups. CONCLUSION: Our results show that olfactory training can slightly improve odor threshold levels in patients with traumatic anosmia, but did not improve the odor identification ability. Nevertheless, clinical improvement or benefit in quality of life from olfactory training needs further investigation.

You or me? Disentangling perspectival, perceptual, and integrative mechanisms in heterotopagnosia.

Heterotopagnosia-without-Autotopagnosia (HwA) is characterized by the incapacity to point to body parts on others, but not on one's own body. This has been classically interpreted as related to a self-other distinction, with impaired visual representations of other bodies seen in third person perspective (3PP), besides spared own body somatosensory representations in 1PP. However, HwA could be impacted by a deficit in the integration of visual and somatosensory information in space, that are spatially congruent in the case of one's own body, but not for others' body. Here, we test this hypothesis in a rare neurological patient with HwA, H+, as well as in a control patient with a comparable neuropsychological profile, but without HwA, and in age-matched healthy controls, in two experiments. First, we assessed body part recognition in a new task where somatosensory information from the participant's body and visual information from the target body shown in virtual reality was never aligned in space. Results show that, differently from the flawless performance in controls, H+ committed errors for not only the body of others in 3PP, but for all conditions where the information related to the real and the target body was not spatially congruent. Then, we tested whether the integration between these multisensory bodily cues in space, as during visuo-tactile stimulation in the full-body illusion, improves the patient's performance. Data show that after the stimulation prompting visuo-tactile integration, but not in control conditions, the patient's abilities to process body parts improved up to normal level, thus confirming and extending the first findings. Altogether, these results support a new interpretation of HwA as linked to the matching between somatosensory inputs from one's body and visual information from a body seen at a distance, and encourage the application of multisensory stimulation and virtual reality for the treatment of body-related disorders.

Transcranial magnetic stimulation improves naming in Alzheimer disease patients at different stages of cognitive decline.

OBJECTIVE: Word-finding difficulty (anomia) is commonly observed in Alzheimer's dementia (AD). The aim of this study was to assess the effect of repetitive transcranial magnetic stimulation (rTMS) applied to the dorso-lateral prefrontal cortex (dlPFC) on picture naming in 24 probable AD patients with different degrees of cognitive decline. METHODS: High-frequency rTMS was applied to the left and right dlPFC during object and action naming in AD patients. A sham stimulation was used as a control condition. RESULTS: Whilst, as previously reported, stimulation to both the left and the right dlPFC improved action, but not object naming in the mild AD group; an improved naming accuracy for both classes of stimuli was found in the moderate to severe group. CONCLUSIONS: Repetitive transcranial magnetic stimulation applied to the dlPFC improves naming performance also in the advanced stages of AD. Moreover, in the severe group the effect is not specific for action naming, as in the case of the mild AD group. These findings suggest that rTMS can affect the intrinsic ability of the brain to restore or compensate for damaged function and may represent an useful new tool for cognitive rehabilitation.

Verbal auditory agnosia in a patient with traumatic brain injury: A case report.

RATIONALE: Verbal auditory agnosia is the selective inability to recognize verbal sounds. Patients with this disorder lose the ability to understand language, write from dictation, and repeat words with reserved ability to identify nonverbal sounds. However, to the best of our knowledge, there was no report about verbal auditory agnosia in adult patient with traumatic brain injury. PATIENT CONCERNS: He was able to clearly distinguish between language and nonverbal sounds, and he did not have any difficulty in identifying the environmental sounds. However, he did not follow oral commands and could not repeat and dictate words. On the other hand, he had fluent and comprehensible speech, and was able to read and understand written words and sentences. DIAGNOSIS: Verbal auditory agnosia INTERVENTION:: He received speech therapy and cognitive rehabilitation during his hospitalization, and he practiced understanding of verbal language by providing written sentences together. OUTCOMES: Two months after hospitalization, he regained his ability to understand some verbal words. Six months after hospitalization, his ability to understand verbal language was improved to an understandable level when speaking slowly in front of his eyes, but his comprehension of verbal sound language was still word level, not sentence level. LESSONS: This case gives us the lesson that the evaluation of auditory functions as well as cognition and language functions important for accurate diagnosis and appropriate treatment, because the verbal auditory agnosia tends to be easily misdiagnosed as hearing impairment, cognitive dysfunction and sensory aphasia.

Vestibular stimulation improves insight into illness in schizophrenia spectrum disorders.

Impaired insight into illness (IMP-INS) is common among individuals with schizophrenia spectrum disorders (SSD), contributing to medication nonadherence and poor clinical outcomes. Caloric vestibular simulation (CVS) is typically used to assess peripheral vestibular system function. Left cold CVS is also a transiently effective treatment for IMP-INS and hemineglect secondary to right brain hemisphere stroke, and possibly for IMP-INS and mood stabilization in patients with SSD. Participants with SSD and moderate-to-severe IMP-INS participated in an exploratory double blind, crossover, randomized controlled study of the effects of CVS on IMP-INS. Participants sequentially received all experimental conditions-left cold (4°C), right cold, and body temperature/sham CVS-in a random order. Repeated measures ANOVA were performed to compare changes in IMP-INS, mood and positive symptom severity pre and 30min post CVS. A significant interaction was found between CVS condition, time, and body temperature nystagmus peak slow phase velocity (PSPV) for IMP-INS, indicating that single session left cold CVS transiently improved IMP-INS while right cold CVS may have worsened IMP-INS, particularly in participants with greater vestibular reactivity (i.e. higher PSPV) to body temperature CVS. The procedure's effectiveness is attributed to stimulation of underactive right hemisphere circuits via vestibular nuclei projections to the contralateral hemisphere.

Consequences of Anosognosia on the Cost of Caregivers' Care in Alzheimer's Disease.

BACKGROUND: Anosognosia is common in patients with Alzheimer's disease (AD) and it is frequently related to an increase in time of care demand. OBJECTIVE: The aim of the study was to examine the effect of anosognosia on the total costs of informal care in patients with AD. METHODS: This was a prospective longitudinal study with community-dwelling AD patients. Anosognosia, time of informal care, and the use of support services (e.g., day care centers) were recorded at baseline and after 24 months. The cost of informal caregiving was calculated as 'market price'. RESULTS: At baseline, the prevalence of anosognosia was 54.3% (n = 221), and 43.9% were classified as mild-AD. The average time of care was 5 h/day±2.4 (IADL: 1.3 h/day±1.4 and BADL: 3.6 h/day±1.5). Thirty percent of the patients used home care services, and 25.1% attended a day care center. Patients with anosognosia received more time of care and were more likely to use support services than did their no-anosognosia peers, including institutionalization. The mean cost of support services was 490.4€ /month (SD = 413.1€; range = 25-2,212.38€), while the overall cost of care (support services plus informal care) was 1,787€ /month (SD = 972.4€), ranging from 834.1€ in mild-AD without anosognosia patients, to 2,424.8€ in severe-AD with incident anosognosia patients. CONCLUSIONS: Anosognosia was associated with an increased number of hours of informal care, and a greater use of support services, regardless of the severity of the dementia, which lead to an increase of the total family-care costs.

Speech discrimination and lip reading in patients with word deafness or auditory agnosia.

The purpose of this study was to assess the ability of four patients with word deafness or auditory agnosia to discriminate speech by reading lips. The patients were studied using nonsense monosyllables to test for speech discrimination, a lip reading test, the Token Test for auditory comprehension, and the Aphasia test. Our results show that patients with word deafness or auditory agnosia without aphasia can improve speech comprehension by reading lips in combination with listening, as compared with lip reading or listening alone. In conclusion, lip reading was shown to be useful for speech comprehension among these patients.

[Autotopagnosia ameliorated by looking at the image reflected in a mirror].

A 52-year-old right-handed man presented progressive dystonia and apraxia of his right hand of five years' duration. He also suffered from parkinsonian features such as rigidity or impaired postural reflexes. Serial investigation of brain MRI revealed progressive cerebral atrophy, which started in the left parietal lobe, and subsequently extended to both hemispheres. He was clinically diagnosed as corticobasal degeneration. He could not point at any part of his own body in response to verbal or visual commands. On the other hand, he could point at every part of the examiner's body or of the illustrated body image. Deep sensations and linguistic functions were not involved. This cognitive impairment was regarded as autotopagnosia. In contrast with inability to recognize any part of the own body in response to the commands, he could name every part of his body as soon as the examiner touched there. Moreover, his symptoms of autotopagnosia were ameliorated by looking at himself in a mirror; he could point at any part of his own body. Disconnection between primary proprioceptive sensory area and the center of body schema was thought to be the mechanism of autotopagnosia in this patient, because the impairment improved with the aid of visual or tactile informations. We speculated the lesion was the left parietal lobe.