Brainstem reflexes in neuro-Behçet disease.

We hypothesized that brainstem responses may allow detection of functional brainstem changes in patients with neuro-Behçet Disease (NBD). Thus, we recorded electrically-induced blink reflex (eBR), auditory blink reflex (aBR) and electrically-induced masseter inhibitory reflex (eMIR) in 16patients with NBD. However, these neurophysiological tests proved to have a poor overall sensitivity compared to neuroimaging for the diagnosis of brainstem lesions. They also showed low sensitivity for the differential diagnosis of focal pontine lesion versus diffuse brainstem disease in NBD.

Startle responses after different stimulus modalities differ in stroke.

OBJECTIVES: The auditory startle reaction (ASR) and startle reflex to somatosensory inputs (SSS) are stereotypical responses to sudden and unexpected stimuli, which are generated in the caudal brainstem reticular formation. Changes of ASR are relatively well known in stroke. Here, we aimed to investigate central pathways of SSS and plasticity changes of SSS circuits in different stages and localizations of stroke, by comparing with ASR. METHODS: We prospectively included 39 patients with stroke between June 2009 and June 2013, and 23 age and gender-matched healthy subjects. ASR and SSS were recorded over orbicularis oculi, sternocleidomastoid, biceps brachii (BB), and abductor policis brevis muscles (APB) using surface electrodes. RESULTS: There were supratentorial and infratentorial lesions in both acute and chronic stages. Overall, ASR probability was similar between groups (P=0.981). However, ASR probability was increased for BB and APB recordings on symptomatic sides of stroke patients with high amplitudes and long durations, most prominently on symptomatic sides of pontine strokes. Latencies and presence rates of SSS did not differ between any subgroups of stroke and healthy subjects. CONCLUSION: ASR is facilitated in arm and hand muscles on symptomatic sides of stroke patients, whereas SSS did not show any significant changes according to stroke.

Mentalis muscle related reflexes.

The mentalis muscle (MM) arises from the incisive fossa of the mandible, raises and protrudes the lower lip. Here, we aim to characterize responses obtained from MM by supraorbital and median electrical as well as auditory stimuli in a group of 16 healthy volunteers who did not have clinical palmomental reflex. Reflex activities were recorded from the MM and orbicularis oculi (O.oc) after supraorbital and median electrical as well as auditory stimuli. Response rates over MM were consistent after each stimulus, however, mean latencies of MM response were longer than O.oc responses by all stimulation modalities. Shapes and amplitudes of responses from O.oc and MM were similar. Based on our findings, we may say that MM motoneurons have connections with trigeminal, vestibulocochlear and lemniscal pathways similar to other facial muscles and electrophysiological recording of MM responses after electrical and auditory stimulation is possible in healthy subjects.

Auditory evoked blink reflex in peripheral facial paresis.

PURPOSE: The auditory blink reflex (ABR) is a teleceptive reflex consisting of an early brief muscle contraction of the orbicularis oculi in response to sound stimuli. Constriction of the orbicularis oculi in response to auditory stimulation is accepted as a part of the startle reaction. The blink reflex and ABR might share a final common pathway, consisting of facial nerve nuclei and the facial nerve and may have common premotor neurons. METHODS: In this study, the authors evaluated the value of the ABR in patients with peripheral facial palsy (PFP), cross-checking the results with commonly used blink reflex changes. RESULTS: In total, 83 subjects with PFP and 34 age-matched healthy volunteers were included. Auditory blink reflex was elicited in all control subjects and in 36 PFP cases on the paralytic sides (43.3%), whereas it was asymmetric in 30.1% of the patients. Auditory blink reflex positivity was significantly lower in PFP cases with increasing severity. Blink reflex results were largely correlated with ABR positivity. CONCLUSIONS: Auditory blink reflex is a useful readily elicited and sensitive test in PFP cases, providing parallel results to blink reflex and being affected by disease severity.

Brainstem and spinal reflex studies in patients with primary progressive freezing of gait.

Our aim was to investigate the extent and pattern of involved pathways using brainstem and spinal reflexes by comparing primary progressive freezing of gait (PPFOG) progressive supranuclear palsy (PSP) with FOG. Seven patients with PPFOG and age and sex matched seven PSP patients and 16 healthy subjects were included in the study. All subjects underwent blink reflex (BR), trigemino-cervical reflex (TCR), auditory startle reflex (ASR) and long latency flexor reflex (LLFR) investigations under the same conditions. All three groups had normal BR latencies. ASR probability was lowest in the PSP group and was highest in PPFOG (p=0.005). The presence rate of TCR was lowest in PSP and it was highest in PPFOG (p=0.007 for SC and p=0.023 for SCM). The presence rate and amplitude of LLFR (R II) were decreased in the PSP group (p=0.010 and p=0.031, respectively) whereas it was in a continuous pattern in some of PPFOG patients. ASR, TCR and LLFR were all inhibited in PSP and we suggest that suppression of all three reflexes is probably related to degeneration of brainstem reticular formation and basal ganglia connections. However, interestingly, in PPFOG, excitabilities of ASR and TCR circuits are increased suggesting loss of pathways mediating suprasegmental control.

Understanding the features of posterior auricular muscle response in a facial nerve disease prototype.

OBJECTIVES: This study aims to compare and investigate the changes of posterior auricular muscle response (PAMR) following peripheral facial nerve palsy (PFP) with blink reflex (BR). PATIENTS AND METHODS: A total of 75 idiopathic PFP patients and age and sex-matched 38 healthy volunteers were included. Patients with PFP were classified into two groups including early (≤6 months) and late (>6 months) based on the duration of symptoms. Following clinical evaluation, PAMR and BR were recorded. A comparison was performed among the early PFP group (n=52), late PFP group (n=23) and healthy volunteers (n=38). RESULTS: We obtained PAMR in 78.9% (n=30) of healthy volunteers, in 60.9% (n=14) of late and in only 38.5% (n=20) of early PFP patients (p=0.001). No habituation was observed following repeated stimuli. The mean latencies were 9.1±1.6, 10.9±1.9 and 12.3±2.0 msec., respectively (p=0.000). R1 and R2 latencies were longer in the early PFP group, compared to other groups (p=0.000). CONCLUSION: Posterior auricular muscle response exhibits changes in a manner similar to R1 and R2 of BR in early and late PFP. The occurrence rate of PAMR seems to be lowest or its latency is prolonged in the early PFP.

Compulsive behaviors in patients with Parkinson's disease.

OBJECTIVE: Several impulse control disorders (ICDs) may develop in patients with Parkinson's disease (PD). We aimed to identify the frequency and phenomenology of ICDs in our PD population. METHODS: Among 554 PD patients examined in a 3-year period, we identified 33 patients with ICDs. Disease duration, gender, and age-matched 65 PD patients without ICDs were selected as controls. We noted age-at-onset, duration, and severity of PD, dose and types of dopaminergic treatment, as well as presence of motor complications in both groups. RESULTS: Of 554 patients, 33 (5.9%) had ICDs, of whom, 27 were men (81%), mean age-at onset of PD was 48 and disease duration 8 years. While all patients with ICDs were on dopamine agonist drugs (+/- an adjuvant), all but 2 of controls were on dopamine agonists. Punding was the most frequent behavioral problem (57%), 42% exhibited aggressive hypersexuality, 27% compulsive eating, 24% pathologic shopping, and 21% compulsive medication. Severity of PD, presence of l-Dopa-induced motor complications, l-Dopa equivalent doses of dopamine agonists administered were not statistically different between 2 groups. CONCLUSIONS: In this study performed in a tertiary clinic for movement disorders in Turkey, several ICDs occurred in a small group of PD patients, mostly in men with young-onset disease, similar to the previous reported series. However, in contrast to the Western series, the number of gamblers was quite low because gambling is illegal in our country. We did not find any association between ICDs and severity of PD as well as doses of dopaminergic agents.

Long term follow-up of Parkinson's disease patients with impulse control disorders.

OBJECTIVE: Impulse control disorders (ICDs) are mainly triggered by dopaminergic therapy in Parkinson's disease (PD). Previously, we failed to identify a relationship between the types of dopaminergic therapy and occurrence of ICDs in 33 PD patients. In this study, we aim to evaluate the outcome of ICD behaviors in the same patient group. PATIENTS AND METHODS: Among 33 patients with ICDs, 22 patients were included. Demographics, dopaminergic therapy and disease severity were compared between two time points (Time 1: time of diagnosis of ICD, Time 2: last visit) and between patients who recovered from ICDs and with ongoing ICDs. Types of antipsychotic and antidepressant medication were noted. RESULTS: Mean follow-up period was 43.2 months. At Time 2 mean dopamine agonist (DA) dose was significantly lower, levodopa dose and total UPDRS score was significantly higher. ICDs were dissolved in 16 patients (73%), but persisted in six (27%). In ICD(+) subgroup, DA doses in Time 1 was found significantly higher than ICD(-). However, age, PD severity, disease duration and levodopa dosage were similar. Fourteen patients were prescribed atypical antipsychotics and 13 antidepressants. In ICD(+) group, symptoms of ICDs were mainly increased libido and compulsive eating. CONCLUSIONS: Although we studied a small number of patients the recovery from compulsive behaviors may be associated with the decrease in DA dosage and increase in levodopa. Furthermore, majority were given antipsychotic and/or antidepressant drugs. It is difficult to speculate which strategy could be more effective on the improvement of ICDs in such a small group. In patients who were on high doses of DA, ICDs could be persistent.