Seizure outcome trajectories in a well-defined cohort of newly diagnosed juvenile myoclonic epilepsy patients.

OBJECTIVE: To investigate the temporal course of medication response and associated prognostic factors in a cohort of juvenile myoclonic epilepsy (JME) patients over a long-term follow-up. MATERIALS AND METHODS: Data from 113 JME patients diagnosed according to recently proposed class II criteria were retrospectively reviewed. Early sustained remission was defined as 4-year seizure remission starting within 2 years from the first antiseizure medication (ASM) intake, as opposed to delayed sustained remission. Spontaneous relapse rate (ie, not related to ASM withdrawal) was also investigated, along with factors associated with seizure relapse. RESULTS: Four-year seizure remission was obtained by 76/113 (67.3%) subjects. Early sustained remission was achieved by 45/76 (59.2%) patients. Absence seizures were significantly associated with no-remission at multivariable multinomial logistic regression analysis. Catamenial seizures and earlier age at epilepsy onset significantly predicted delayed sustained remission. Spontaneous seizure relapse after 4-year remission occurred in 15.7% of patients with early sustained remission and in 35.5% of those with delayed sustained remission (p = 0.045). The most common concomitant factors for a spontaneous relapse were irregular lifestyle habits and pregnancy-related switch from valproate to another ASM. Patients with a history of catamenial seizures were more likely to experience a spontaneous generalized tonic-clonic seizure relapse after 4-year remission at univariable analysis. SIGNIFICANCE: Our data support the prognostic relevance of early medication response in JME patients. Furthermore, the prognostic significance of catamenial seizures and the impact of valproate switch on seizure relapse after a prolonged remission account for the challenging therapeutic management of women with childbearing potential.

Persistent treatment resistance in genetic generalized epilepsy: A long-term outcome study in a tertiary epilepsy center.

OBJECTIVE: To assess prognostic patterns and investigate clinical and electroencephalography (EEG) variables associated with persistent treatment resistance in a population of genetic generalized epilepsy (GGE) patients with a long-term follow-up. METHODS: Data from GGE patients followed from 1975 to 2019 were reviewed retrospectively. Subjects with a follow-up >10 years, starting from epilepsy diagnosis, were included. Persistent treatment resistance was defined as the absence of any period of remission ≥1 year despite treatment with two appropriate and adequate antiepileptic drugs (AEDs). RESULTS: One hundred ninety-nine patients were included. The median age was 39.5 years (interquartile range [IQR] 30-49) and the median follow-up was 27 years (IQR 18-35). The most common syndrome was juvenile myoclonic epilepsy (JME), diagnosed in 44.2% of patients. During follow-up, 163 subjects (81.9%) experienced 3-year remission from any seizure type, whereas 5- and 10-year remission occurred in 141 (70.8%) and 92 (46.2%) cases, respectively. The most common prognostic pattern was a relapsing-remitting course, observed in 80 patients (40.2%), whereas 29 (14.6%) displayed persistent treatment resistance. According to multivariable logistic regression analysis, febrile seizures (FS), specific EEG patterns (namely generalized paroxysmal fast activity, GPFA) and valproate (VPA) resistance were the only variables significantly associated with persistent treatment resistance. JME was the only epilepsy syndrome statistically associated with persistent treatment resistance in univariable logistic regression analysis. SIGNIFICANCE: Persistent treatment resistance was observed in almost 15% of GGE patients followed in a tertiary epilepsy center. A worse outcome was associated with specific clinical variables (JME, FS) and EEG patterns (GPFA).

Doing without valproate in women of childbearing potential with idiopathic generalized epilepsy: Implications on seizure outcome.

OBJECTIVE: Valproate (VPA) use in women with idiopathic generalized epilepsy (IGE) who are of reproductive age has been a matter of concern and debate, which eventually led to the recent restrictions by regulatory agencies. The aim of our study was to investigate the relationship between VPA avoidance/switch and seizure outcome in women of childbearing potential. METHODS: We retrospectively reviewed data from female patients with IGE, 13-50 years of age, followed since 1980. We evaluated the prescription habits, and the rate of VPA switch for other antiepileptic drugs (AEDs) and its prognostic implications. Seizure remission (SR) was defined as the absence of any seizure type more than 18 months before the last medical observation. The main aim of the study was to assess (a) possible changes in seizure outcome related to VPA switch for other AEDs, especially in patients planning a pregnancy; and (b) possible differences in SR based on the presence/absence of VPA at last observation. RESULTS: One hundred ninety-eight patients were included in the study. Overall SR at last medical observation was 62.7%. SR significantly differed between subjects taking and those not taking VPA (P < .001) at last visit. Multiple regression models showed that taking VPA at last medical observation was strongly associated with SR in both the general population (P < .001) and the juvenile myoclonic epilepsy (JME) group (P < .001). Thirty-six (70.6%) of 51 patients who switched from VPA during follow-up experienced a clinical worsening. Switching back to VPA was more frequently associated with SR at last observation (P < .001). In those patients who substituted VPA in view of a pregnancy, SR and drug burden (monotherapy vs polytherapy) differed significantly before and after the switch. SIGNIFICANCE: Our study suggests that VPA avoidance/switch might be associated with unsatisfactory seizure control in women with IGE who are of childbearing potential. Our findings further highlight the complexity of the therapeutic management of female patients of reproductive age.

Anxiety as the only manifestation of focal non-convulsive status epilepticus: case report and review of the literature.

Psychiatric disorders represent common comorbidities in epileptic patients. Sometimes anxiety is part of the ictal semiology, especially during seizures arising from/involving frontal or temporal lobes. We describe a patient with focal epilepsy and recurrent hyperkinetic seizures who also presented prolonged episodes characterized by massive anxiety, alarm and fear. A Video-Electroencephalographic monitoring performed during one of these attacks revealed a continuous epileptiform activity over the right frontal regions, consistent with a focal non-convulsive status epilepticus accounting for the patient's psychiatric symptoms. Our case confirms the complex relationship between epilepsy and anxiety. A review of the literature is also included.

Ictal epileptic headache in adult life: Electroclinical patterns and spectrum of related syndromes.

OBJECTIVES: Both headache and epilepsy are frequent paroxysmal disorders that often co-occur or are related in numerous ways. Although ictal epileptic headache has become the focus of several studies, this remains a very rare and not well-known phenomenon. Electroclinical features, pathophysiology, and syndromic context are heterogeneous. We investigated the electroclinical and neuroimaging findings in a population of adult patients with ictal epileptic headache. METHODS: We retrospectively examined 8800 EEG recordings of almost 4800 patients admitted to our video-EEG laboratory from 2010 to 2013 with a history of well-documented epilepsy. We selected patients who reported headache closely related to a seizure documented by video-EEG or 24-hour ambulatory EEG. We analyzed ictal electroclinical features of headache, and we defined the related epileptic syndromes. RESULTS: We identified five patients with ictal epileptic headache. Two patients described tension headache during an epileptic seizure. In three patients, the headache was accompanied by other "minor" neurological symptoms mimicking a migrainous aura. In all cases, the headache stopped with the end of the epileptic activity. Three patients had a history of partial symptomatic epilepsy with cerebral lesions (low grade glioma, astrocytoma, porencephalic cyst) in the left posterior regions, whereas two patients were affected by idiopathic generalized epilepsy. CONCLUSION: This study confirms the rarity of ictal epileptic headache. To date, well-documented video-EEG cases remain as exceptional reports, especially in cases of idiopathic generalized epilepsies. Moreover, we confirm the main involvement of posterior regions in patients with ictal epileptic headache affected by partial symptomatic epilepsies.

Cryptogenic focal epilepsy and "hidden" celiac disease in adulthood: a causal or accidental link?

PURPOSE: Celiac disease (CD) is an immuno-mediated small bowel disease characterized by chronic inflammation due to a permanent intolerance to gliadin. Several neurological complications have been described, including epilepsy, whose evolution might often improve by adopting gluten-free diet (GFD). We studied a population of adult patients affected by posterior drug-resistant epilepsy of unknown cause by performing an accurate screening for CD. In the selected patients presenting the association of epilepsy and CD, we characterized the related electro-clinical features. MATERIALS AND METHODS: We consecutively identified 211 adult subjects affected by drug-resistant cryptogenic focal epilepsy with posterior seizures. All these patients underwent serological screening for CD. In 10 subjects positive serological tests allowed to perform a CD diagnosis (confirmed by duodenal biopsy). For each patient clinical and EEG data, neuroimaging studies, serological and histological findings were revised, as well as response to GFD, defined as an improvement in seizure outcome. RESULTS: A significant delay between diagnosis of epilepsy and CD was documented. Visual ictal manifestations were reported in half of subjects. In all cases, interictal EEG showed slow and epileptiform abnormalities over parietal-occipital and temporal regions; in three cases, FOS phenomenon was observed. Four patients had familiar history of CD and six cases showed clinical signs/symptoms of malabsorption. GFD led to a reduction of seizure frequency in half of patients. CONCLUSIONS: "Posterior" ictal semiology, peculiar EEG patterns and drug-resistance emerge as the most interesting characteristics. CD screening should be performed in epilepsy patients presenting such features.

Ictal epileptic headache revealing non convulsive status epilepticus in a case of eyelid myoclonia with absences.

Epileptic seizures and headache attacks are two common neurologic phenomena characterized by paroxysmal alteration of brain functions followed by complete restauration of the baseline condition. Headache and epilepsy are related in numerous ways, and they often co-occur. Although the link between these two diseases is not completely clear, several clinical, physiopathological and therapeutic features overlap. Headache is reported in association with epileptic seizures as a pre-ictal, ictal or post-ictal phenomenon. We present the case of a 40 year-old woman affected by eyelid myoclonia with absences (EMA) with a history of prolonged headache attacks. A video-EEG recording performed during one of these episodes showed subcontinuous epileptic activity consisting of generalized spike-and-wave discharges (GSWDs), clinically associated with tensive headache. Our work represents one of the few well EEG-documented cases of ictal epileptic headache in idiopathic generalized epilepsy (IGE).

Clinical experience with intravenous valproate as first-line treatment of status epilepticus and seizure clusters in selected populations.

OBJECTIVE: The aim of this study was to evaluate the efficacy and safety of intravenous valproate (i.v. VPA) as first-line treatment of status epilepticus (SE) and seizure clusters in selected patient populations. METHODS: We enrolled 23 patients (11 females and 12 males; mean age: 61 years) with SE who received i.v. VPA as first-line therapy (25 mg/kg in 100 mL saline infused over 15 min). ECG tracing was monitored before, during, and after infusion. Liver function and serum ammonia tests were conducted after 24 and 72 h of treatment. We evaluate the response of SE to i.v. therapy and short-term outcome. RESULTS: In 15 out of 23 patients (65%), i.v. VPA was effective. In our population, we retrospectively identified three different subgroups: patients with cardiorespiratory comorbidities discouraging the use of traditional SE first-line drugs, patients with specific epileptic subsyndromes (such as idiopathic generalized epilepsy), and patients affected by psycho-organic syndromes. No significant adverse effects were detected. DISCUSSION: Our study shows the clinical relevance of i.v. VPA as first-line therapy of SE in patients with medical conditions contraindicating the use of traditional first-line antiepileptic drugs for SE, and in those presenting with specific forms of SE.

The spectrum of epileptic syndromes with fixation off sensitivity persisting in adult life.

PURPOSE: The term "fixation off sensitivity" (FOS) was proposed by Panayiotopoulos to describe epilepsy/electroencephalography (EEG) changes evoked by the suppression of central vision and fixation. The EEG pattern usually consists of spike/polyspike and waves localized in occipital regions. FOS occurs mainly in children with idiopathic occipital partial epilepsies and rarely in adults. In this retrospective study we evaluated the clinical data, EEG, and magnetic resonance imaging (MRI) findings of patients with epilepsy and FOS persisting in adult life to better define the spectrum of syndromes. METHODS: We selected 15 consecutive patients (12 female/3 male; age range 19-59 years). The main inclusion criterion was the diagnosis of epilepsy with FOS persisting in adult life. We retrospectively analyzed clinical EEG and neuroimaging data. KEY FINDINGS: We observed a female prevalence (F/M = 12/3). Eight patients presented both simple and complex partial seizures, whereas seven had only complex partial seizures. Partial seizures evolved into generalized seizures/hemiconvulsions in nine cases. The FOS pattern consisted of spike-and-wave and slow-wave abnormalities with posterior localization (bilateral in eight/monolateral in seven). We recorded seizures in 10/15 patients. All showed a posterior onset (bilateral in 2/left in 2/right in 6). FOS was prevalent in symptomatic epilepsy (cortical malformations in 7; celiac disease in 3; calcified vascular malformation in 1). One patient presented cryptogenic epilepsy and only three idiopathic epilepsy (Gastaut syndrome). SIGNIFICANCE: FOS can be observed in adult life in idiopathic epilepsy, representing the "prolongation" of the same phenomenon arisen during childhood. Nevertheless, it often represents the EEG expression of symptomatic epilepsies (cortical malformations/celiac disease).

Ictal epileptic headache as "subtle" symptom in generalized idiopathic epilepsy.

Epilepsy and migraine are common neurologic chronic disorders with episodic manifestations characterized by recurrent attacks and a return to baseline conditions between attacks. Epilepsy and migraine are frequently observed in comorbidity, with the occurrence of one disorder increasing the probability of the other: Migraine occurs in about one-fourth of patients with epilepsy, whereas epilepsy is present in 8-15% of patients with migraine. The link between headache and seizures is controversial and multifactorial. In epilepsy, headache can be seen as a preictal, ictal, or postictal phenomenon. In this report, we describe a case of a 37-year-old patient, affected by both drug-resistant generalized idiopathic epilepsy and headache, who displayed the sudden onset of a headache attack referred during a 24-h electroencephalography (EEG). The EEG tracing during this event revealed the activation of subcontinuous epileptic activity consisting of generalized spike-wave discharges (GSWDs) and generalized polyspike and wave discharges (GPSWDs) that persisted for 60 min, that is, until the disappearance of the headache. The case we describe appears to be original in that it represents one of the few EEG-documented ictal epileptic headaches in generalized idiopathic epilepsy.

Blockage of A2A and A3 adenosine receptors decreases the desensitization of human GABA(A) receptors microtransplanted to Xenopus oocytes.

We previously found that the endogenous anticonvulsant adenosine, acting through A(2A) and A(3) adenosine receptors (ARs), alters the stability of currents (I(GABA)) generated by GABA(A) receptors expressed in the epileptic human mesial temporal lobe (MTLE). Here we examined whether ARs alter the stability (desensitization) of I(GABA) expressed in focal cortical dysplasia (FCD) and in periglioma epileptic tissues. The experiments were performed with tissues from 23 patients, using voltage-clamp recordings in Xenopus oocytes microinjected with membranes isolated from human MTLE and FCD tissues or using patch-clamp recordings of pyramidal neurons in epileptic tissue slices. On repetitive activation, the epileptic GABA(A) receptors revealed instability, manifested by a large I(GABA) rundown, which in most of the oocytes (approximately 70%) was obviously impaired by the new A(2A) antagonists ANR82, ANR94, and ANR152. In most MTLE tissue-microtransplanted oocytes, a new A(3) receptor antagonist (ANR235) significantly improved I(GABA) stability. Moreover, patch-clamped pyramidal neurons from human neocortical slices of periglioma epileptic tissues exhibited altered I(GABA) rundown on ANR94 treatment. Our findings indicate that antagonizing A(2A) and A(3) receptors increases the I(GABA) stability in different epileptic tissues and suggest that adenosine derivatives may offer therapeutic opportunities in various forms of human epilepsy.

Olfactory impairment in autoimmune encephalitis: another piece of the puzzle.

BACKGROUND: Despite being long neglected, olfaction has recently become a focus of intense research in neuroscience, as smell impairment has been consistently documented in both neurodegenerative and neuroinflammatory diseases. Considering the close anatomo-functional correlations between the limbic system and the central olfactory structures, we investigated olfaction in a population of patients with autoimmune encephalitis (AE). METHODS: Nineteen adult subjects (14 males, median age 64 years) diagnosed with definite (14/19) or possible (5/19) AE and followed for ≥ 6 months were enrolled. The Brief Smell Identification Test (B-SIT), a 12-item, forced-choice, scratch-and-sniff measure, was used to assess the patients' olfactory function in comparison with a group of sex- and age-matched healthy controls (HC). According to the B-SIT score, subjects were classified as anosmic (< 6), hyposmic (6-8) and normal (≥ 9). Electro-clinical, laboratory and neuroimaging findings were reviewed. RESULTS: Smell impairment was revealed in 15/19 patients (9 hyposmic, 6 anosmic), compared with 5/19 HC (p = 0.0029). Age, gender and smoking habits did not affect the participants' performance at B-SIT. Olfactory dysfunction appeared more common among patients with definite AE (p = 0.0374), regardless of autoantibody status. Subjects with higher modified Rankin Scale (mRS) scores at AE onset more likely presented hyposmia/anosmia (p = 0.033), and so did those with bilateral ictal/interictal EEG abnormalities (p = 0.006). CONCLUSIONS: We found olfaction to be impaired in a significantly large proportion of AE cases. Smell deficits appeared more common in subjects with severe AE (as indicated by both definite diagnosis and higher mRS score), and might represent an additional feature of immune-mediated encephalitis.

High rates of early remission pattern in adult-onset compared with earlier-onset idiopathic generalized epilepsy: A long-term follow-up study.

OBJECTIVE: To investigate electroclinical characteristics and prognostic patterns of adult-onset vs. younger-onset idiopathic generalized epilepsy (IGE) patients during long-term follow-up. METHODS: In this single-center retrospective cohort comparative study, adult-onset IGE was defined as onset after 20 years of age. Patients with a follow-up duration between 10 and 30 years from epilepsy diagnosis were enrolled. Maximum follow-up duration was limited to 30 years to ensure a better comparison of prognostic data between adult-onset and younger-onset patients. The Benjamini-Hochberg false discovery rate (FDR) method was applied to obtain FDR-adjusted p-values. RESULTS: A total of 177 IGE patients were recruited and 27 adult-onset IGE patients were identified (15.3%). Follow-up duration was similar between younger- and adult-onset IGE patients and 74% of subjects performed at least one 24-hour EEG recording. Of adult-onset IGE patients, 8/27 were diagnosed with juvenile myoclonic epilepsy, while 19/27 were diagnosed with generalized tonic-clonic seizures (GTCS) only. EEG photosensitivity and absence seizures were significantly less frequent among adult-onset IGE patients as compared with younger subjects. When considering prognostic patterns, an early remission pattern was significantly higher among adult-onset IGE patients as compared with younger-onset IGE patients (55.6% vs. 24%, adjusted p value = 0.007). Antiseizure medication withdrawal was attempted in 3/27 adult-onset patients, and all had GTCS relapses. CONCLUSION: Our study contributes to better defining the electroclinical characteristics and long-term follow-up of adult-onset IGE patients. A favorable long-term seizure outcome was found in adult-onset IGE patients, as evidenced by the high rates of early remission pattern when compared with younger onset patients.

Late-onset seizures and epilepsy: Electroclinical features suggestive of autoimmune etiology.

Introduction: Late-onset epilepsy (LOE) has recently become a topic of intense research. Besides stroke, tumors, and dementia, autoimmune encephalitis (AE) has emerged as another possible cause of recurrent seizures in the elderly, and may account for a proportion of cases of LOE of unknown origin (LOEUO). This 24-h ambulatory electroencephalography (AEEG)-based study compared patients with LOEUO and AE to identify features suggestive of immune-mediated seizures in the elderly. Materials and methods: We retrospectively reviewed 232 AEEG examinations performed in patients over 55 years with ≥6-month follow-up, and selected 21 subjects with AE and 25 subjects with LOEUO. Clinical charts and AEEG recordings were carefully analyzed. Results: Twenty-five patients with LOEUO (12 women, mean age at onset 67.9 years) and 21 AE subjects (8 women, mean age at onset 65.7 years) were enrolled. High-frequency seizures were reported in 20/21 AE and 7/25 LOEUO cases (p < 0.00001). Focal aware seizures were more common in AE (14/21 vs. 6/25, p = 0.00058), whereas "isolated" focal-to-bilateral tonic-clonic seizures occurred in 5/25 patients with LOEUO only (p = 0.053). AE subjects reported ictal autonomic manifestations more frequently (p = 0.0033). Three-hundred-seventy and 24 seizures were recorded in 13/21 patients with AE and 3/25 patients with LOEUO, respectively (p = 0.0006). Interictal epileptiform discharges were observed in 70% of both groups, but their sleep activation was more common in AE (p = 0.06). Conclusion: Our study shows that high-frequency focal seizures with autonomic manifestations should raise the suspicion of AE in the elderly with new-onset seizures. It also highlights the relevant contribution of AEEG, which might reduce the diagnostic delay and provide useful clues to recognize AE.

Scintigraphic, neuroradiological and clinical comparison in two patients with primary sporadic and two with secondary Fahr's disease.

Bilateral striopallidodentate calcification, usually termed Fahr's disease, can give rise to various clinical manifestations including hyperkinetic movement disorders or a hypokinetic Parkinsonian syndrome, behavioural and mood changes, cognitive deficits and even frank dementia. We describe four patients all of whom underwent a detailed scintigraphic, neuroradiological and clinical work-up: two had primary, sporadic Fahr's disease and two had Fahr's disease secondary to hypoparathyroidism. The neuroradiological and clinical studies disclosed similar anatomical and pathological changes in the four patients but variable and sometimes unexpected clinical manifestations. Both patients with primary forms had hypokinetic Parkinsonian syndrome, both patients with secondary forms had hyperkinetic movements. Dopamine autotransporter scan brain scintigraphy disclosed an unexpected unilateral putamen involvement despite substantially symmetric calcifications.

Adenosine receptor antagonists alter the stability of human epileptic GABAA receptors.

We examined how the endogenous anticonvulsant adenosine might influence gamma-aminobutyric acid type A (GABA(A)) receptor stability and which adenosine receptors (ARs) were involved. Upon repetitive activation (GABA 500 microM), GABA(A) receptors, microtransplanted into Xenopus oocytes from neurosurgically resected epileptic human nervous tissues, exhibited an obvious GABA(A)-current (I(GABA)) run-down, which was consistently and significantly reduced by treatment with the nonselective adenosine receptor antagonist CGS15943 (100 nM) or with adenosine deaminase (ADA) (1 units/ml), that inactivates adenosine. It was also found that selective antagonists of A2B (MRS1706, 10 nM) or A3 (MRS1334, 30 nM) receptors reduced I(GABA) run-down, whereas treatment with the specific A1 receptor antagonist DPCPX (10 nM) was ineffective. The selective A2A receptor antagonist SCH58261 (10 nM) reduced or potentiated I(GABA) run-down in approximately 40% and approximately 20% of tested oocytes, respectively. The ADA-resistant, AR agonist 2-chloroadenosine (2-CA) (10 microM) potentiated I(GABA) run-down but only in approximately 20% of tested oocytes. CGS15943 administration again decreased I(GABA) run-down in patch-clamped neurons from either human or rat neocortex slices. I(GABA) run-down in pyramidal neurons was equivalent in A1 receptor-deficient and wt neurons but much larger in neurons from A2A receptor-deficient mice, indicating that, in mouse cortex, GABA(A)-receptor stability is tonically influenced by A2A but not by A1 receptors. I(GABA) run-down from wt mice was not affected by 2-CA, suggesting maximal ARs activity by endogenous adenosine. Our findings strongly suggest that cortical A2-A3 receptors alter the stability of GABA(A) receptors, which could offer therapeutic opportunities.

Functional Gastrointestinal Disorders in Patients With Epilepsy: Reciprocal Influence and Impact on Seizure Occurrence.

Introduction: The complex relationship between the microbiota-gut-brain axis (MGBA) and epilepsy has been increasingly investigated in preclinical studies. Conversely, evidence from clinical studies is still scarce. In recent years, the pivotal role of MGBA dysregulation in the pathophysiology of functional gastrointestinal disorders (FGID) has been recognized. With this background, we aimed to investigate the prevalence of FGID in patients with epilepsy (PWE) and the possible impact of bowel movement abnormalities on seizure recurrence. Methods: A total of 120 PWE and 113 age-, sex-, and BMI-matched healthy subjects (HS) were consecutively enrolled. A questionnaire to evaluate the presence of FGID (according to Rome III diagnostic criteria) was administrated to all participants. In a subgroup of drug-resistant patients, we administered an ad-hoc questionnaire combining Bristol stool charts and seizure diaries to evaluate seizure trends and bowel movement changes. Results: A higher prevalence of FGID in PWE (62.5%) than in HS (39.8%) was found (p < 0.001). The most frequently observed disorder was constipation, which was significantly higher in PWE than in HS (43.3 vs. 21.2%, p < 0.001), and was not associated with anti-seizure medication intake according to multivariable analysis. In drug-resistant patients, most seizures occurred during periods of altered bowel movements, especially constipation. A significant weak negative correlation between the number of days with seizures and the number of days with normal bowel movements was observed (p = 0.04). According to multivariable logistic regression analysis, FGID was significantly associated with temporal lobe epilepsy as compared with other lobar localization (p = 0.03). Conclusions: Our clinical findings shed new light on the complex relationship between epilepsy and the MGBA, suggesting a bidirectional link between bowel movement abnormalities and seizure occurrence. However, larger studies are required to better address this important topic.

Metaplasticity of the human trigeminal blink reflex.

Although synaptic plasticity in the human cerebral cortex is governed by metaplasticity, whether a similar mechanism operates at brainstem level is unknown. In this study in healthy humans we examined the effects and interactions induced by pairing supraorbital nerve high-frequency electrical stimulation (HFS) protocols on the R2 component of the trigeminal blink reflex [Mao, J.B. & Evinger, C (2001) J Neurosci., 21:RC151(1-4)]. Changes in the R2 component were tested by pairing three different priming stimulation protocols inducing long-term potentiation (LTP)-like or long-term depression (LTD)-like effects (LTP-HFS and LTD-HFS), or no change (CONTROL-HFS) with a subsequent test LTP-HFS. Additionally, to examine changes in the R2 component induced by nonspecific factors, two CONTROL-HFS sessions were paired. Priming LTP-, LTD- or CONTROL-HFS potentiated, inhibited or left unchanged the area of the R2 component. Regardless of the type of priming LTP-, LTD- or CONTROL-HFS, the test LTP-HFS induced negligible differences in the R2 component. When two CONTROL-HFS sessions were paired, the test CONTROL-HFS increased the latency and markedly reduced the duration and area of the R2 component. The analysis of the normalized data across the first three experimental sessions, corrected for the inhibitory effects found in the fourth experiment, showed that the test LTP-HFS potentiated the R2 component area of the trigeminal blink reflex only when preceded by a priming LTD-HFS. We propose that homosynaptic metaplasticity might operate in the brainstem circuitry of the blink reflex.