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Aitolo-Akarnania prefecture, western Greece, is an area with strong earthquakes and large active fault systems. The most prominent are the Katouna sinistral strike slip fault and the Trichonis Lake normal fault system. Their proximity to large cities, and the lack of detailed information on their seismogenic potential, calls for multiparametric research. Since 2013, the area’s crustal deformation has been monitored by a dense GNSS Network (PPGNet), consisting of five stations, equipped with Leica and Septentrio receivers. The objective of this network is to define the rate of deformation across these two main fault systems. Data is recorded using two sampling frequencies, 1 Hz and 10Hz, producing hourly and daily files. Daily data is processed using Bernese GNSS Processing Software using final orbits of International GNSS Service. Double-difference solution is computed using phase measurements from the PPGNet network complemented by four stations from Athens’ National Observatory GNSS network and six stations from METRICA network. First results show a NNE movement at PVOG station of 12 mm/y and a similar movement at RETS station of about 9 mm/y. This means that the Trichonis Lake normal fault system, located between these two stations, depicts a slip rate of 3 mm/y. KTCH and RGNI stations move eastwards at a velocity of about 5 mm/y due to the Katouna-Stamna fault system. Data from PPGNet has provided important results on crustal deformation in the area, i.e. slip rates have been attributed to specific fault systems. The comparison and links of these data with broader geodynamic models is now possible and we expect, in a later phase that will provide a more detailed image of the associated seismic hazard for Aitolo-Akarnania. Doi: 10.28991/cej-2021-03091633 Full Text: PDF

Estimation of intracranial pressure (ICP) may be helpful in the management of neurological critically ill patients. It has been shown that ultrasonography of the optic nerve sheath diameter (ONSD) is a reliable tool for non-invasive estimation of increased intracranial pressure (ICP) at hospital admission or in intensive care. Less is known about the estimation of increased ICP and usefulness of ONSD in the prehospital setting. The aim of this review was to elucidate both prevailing and novel applications of ONSD for neurologists and critical care physicians. In this review, we discuss the technique and the novel approach of ONSD measurement, the clinical applications of ONSD in neurology and critical care patients. ONSD measurement is simple, easy to learn, and has diverse applications. ONSD has utility for ICP measurement in intracranial hemorrhage and ischemic stroke, meningitis and encephalitis, and idiopathic intracranial hypertension (IIH). It is also valuable for lesser known syndromes, where an increase of ICP is postulated, such as acute mountain sickness and posterior reversible encephalopathy syndrome. ONSD changes develop in inflammatory or ischemic optic neuropathies. Some papers demonstrate the usefulness of ONSD studies in symptomatic intracranial hypotension. ONSD is a safe and low-cost bedside tool with the potential of screening patients who need other neuroimaging and those who may need an invasive measurement of ICP.

It is unclear whether alterations in cerebral pH underlie Alzheimer's disease (AD) and other dementias. We performed proton spectroscopy after oral administration of histidine in healthy young and elderly persons and in patients with mild cognitive impairment and dementia (total N = 147). We measured cerebral tissue pH and ratios of common brain metabolites in relation to phosphocreatine and creatine (Cr) in spectra acquired from the hippocampus, the white matter (WM) of the centrum semiovale, and the cerebellum. Hippocampal pH was inversely associated with age in healthy participants but did not differ between patients and controls. WM pH was low in AD and, to a lesser extent, mild cognitive impairment but not in frontotemporal dementia spectrum disorders and pure vascular dementia. Furthermore, WM pH provided incremental diagnostic value in addition to N-acetylaspartate to Cr ratio. Our study suggests that in vivo assessment of pH may be a useful marker for the differentiation between AD and other types of dementia.

Background Nutrition is an important modifiable risk factor in Alzheimer's disease. Previous trials of the multinutrient Fortasyn Connect showed benefits in mild Alzheimer's disease dementia. LipiDiDiet investigated the effects of Fortasyn Connect on cognition and related measures in prodromal Alzheimer's disease. Here, we report the 24-month results of the trial. Methods LipiDiDiet was a 24-month randomised, controlled, double-blind, parallel-group, multicentre trial (11 sites in Finland, Germany, the Netherlands, and Sweden), with optional 12-month double-blind extensions. The trial enrolled individuals with prodromal Alzheimer's disease, defined according to the International Working Group (IWG)-1 criteria. Participants were randomly assigned (1:1) to active product (125 mL once-a-day drink containing Fortasyn Connect) or control product. Randomisation was computer-generated centrally in blocks of four, stratified by site. All study personnel and participants were masked to treatment assignment. The primary endpoint was change in a neuropsychological test battery (NTB) score. Analysis was by modified intention to treat. Safety analyses included all participants who consumed at least one study product dose. This trial is registered with the Dutch Trial Register, number NTR1705. Findings Between April 20, 2009, and July 3, 2013, 311 of 382 participants screened were randomly assigned to the active group (n=153) or control group (n=158). Mean change in NTB primary endpoint was −0·028 (SD 0·453) in the active group and −0·108 (0·528) in the control group; estimated mean treatment difference was 0·098 (95% CI −0·041 to 0·237; p=0·166). The decline in the control group was less than the prestudy estimate of −0·4 during 24 months. 66 (21%) participants dropped out of the study. Serious adverse events occurred in 34 (22%) participants in the active group and 30 (19%) in control group (p=0·487), none of which were regarded as related to the study intervention. Interpretation The intervention had no significant effect on the NTB primary endpoint over 2 years in prodromal Alzheimer's disease. However, cognitive decline in this population was much lower than expected, rendering the primary endpoint inadequately powered. Group differences on secondary endpoints of disease progression measuring cognition and function and hippocampal atrophy were observed. Further study of nutritional approaches with larger sample sizes, longer duration, or a primary endpoint more sensitive in this pre-dementia population, is needed., published version, peerReviewed

The ability to recognize facial emotion expressions has been reported to be impaired in Parkinson's disease (PD), yet previous studies showed inconsistent findings. The aim of this study was to further investigate facial emotion recognition (FER) in PD patients and its association with demographic and clinical parameters (including motor and nonmotor symptoms).Thirty-four nondemented PD patients and 24 age- and sex-matched healthy controls (HC) underwent clinical neurological and neuropsychological assessment, standardized olfactory testing with Sniffin' Sticks, and the Ekman 60 Faces Emotion Recognition Test.PD patients had a significantly lower score on the total FER task than HC (p = .006), even after controlling for the potential confounding factors depression and apathy. The PD group had a specific impairment in the recognition of surprise (p = .007). The recognition of anger approached statistical significance (p = .07). Increasing chronological age and age at disease onset were associated with worse performance on the FER task in PD patients. Olfactory function along with PD diagnosis predicted worse FER performance within all study participants.Facial emotion recognition and especially the recognition of surprise are significantly impaired in PD patients compared with age- and sex-matched HC. The association of FER with age and olfactory function is endorsed by common structures that undergo neurodegeneration in PD. The relevance of FER in social interaction stresses the clinical relevance and the need for further investigation in this field. Future studies should also determine whether impaired FER is already present in premotor stages of PD.

It is unclear whether alterations in cerebral pH underlie Alzheimer's disease (AD) and other dementias. We performed proton spectroscopy after oral administration of histidine in healthy young and elderly persons and in patients with mild cognitive impairment and dementia (total N = 147). We measured cerebral tissue pH and ratios of common brain metabolites in relation to phosphocreatine and creatine (Cr) in spectra acquired from the hippocampus, the white matter (WM) of the centrum semiovale, and the cerebellum. Hippocampal pH was inversely associated with age in healthy participants but did not differ between patients and controls. WM pH was low in AD and, to a lesser extent, mild cognitive impairment but not in frontotemporal dementia spectrum disorders and pure vascular dementia. Furthermore, WM pH provided incremental diagnostic value in addition to N-acetylaspartate to Cr ratio. Our study suggests that in vivo assessment of pH may be a useful marker for the differentiation between AD and other types of dementia.

Research has recently focused on cognitive dysfunction in multiple sclerosis (MS). Cognitive deficits are frequently encountered in patients and account for important impairment in quality of life, therefore posing a major therapeutic challenge for the disease. We presently review studies on cognitive effects of pharmacological treatments in MS. There is evidence for a possible beneficial effect of immunomodulatory treatments, particularly of interferons, and also of acetylcholinesterase inhibitors on cognition in MS, which, however, requires evaluation in larger, multi-centre, longitudinal studies. Methodological issues and future prospects regarding the investigation of this issue are also discussed.

In the present study, we examined relationships between neuropsychological functions and brain single photon emission computed tomography (SPECT) regional cerebral blood flow (rCBF) observed at presurgical evaluation for deep brain stimulation (DBS) of the subthalamic nucleus (STN) in advanced Parkinson’s disease (PD) patients. Twenty advanced non-demented PD patients, candidates for DBS surgery, underwent perfusion brain SPECT study and neuropsychological assessment prior to surgery (range: 30–50 days). Patients were further assessed using the Unified Parkinson’s Disease Rating Scale (UPDRS) and Hoehn and Yahr (H&Y) scale. During all assessments patients were “on” standard medication. NeuroGam software, which permits voxel by voxel analysis, was used to compare the brain perfusion of PD patients with a normal database adjusted for sex and age. Neuropsychological scores were compared to age, education and sex-adjusted normative databases. Our results indicated that the distribution of rCBF showed significant differences when compared to an age- and sex-adjusted normative database. We found impaired blood flow in 17 (85%) of our patients in the left prefrontal lobe, in 14 (70%) in the right prefrontal lobe and in 11 (55%) in the left frontal and right parietal lobes. Neuropsychological testing revealed that 18 (90%) of our patients had significant impairments in measures of executive functions (set-shifting) and 15 (75%) in response inhibition. Furthermore, we found significant correlations between measures of visual attention, executive functions and the right frontal lobe region. The presence of widespread blood flow reduction was observed mainly in the frontal lobes of dementia-free patients with advanced PD. Furthermore, performance on specific cognitive measures was highly related to perfusion brain SPECT findings.

Alzheimer's disease (AD) is characterized by a progressive decline of cognitive functions and represents the most common form of dementia and a major cause of morbidity and mortality in the modern, westernized societies. There is accumulating evidence to support the hypothesis that a primary cerebral vascular dysfunction initiates a cascade of events that lead to neuronal injury in Alzheimer's dementia. The endothelium, in specific, constitutes a part of the blood brain barrier, the dysfunction of which is thought to play an important role to disturbed amyloid-β homeostasis and infiltration of the brain parenchyma with circulating toxic molecules in the disease. Furthermore, the endothelium itself is under certain conditions capable of producing neurotoxic and inflammatory factors, whereas common growth factors regulate the development and maintenance of both neurons and blood vessels. Reliance of both endothelial and neuronal cells on mitochondrial integrity and common molecular pathways for apoptosis also imply that there is a link between vascular pathology and neurodegeneration. The present article intends to review available evidence on molecular players implicated in the above mechanisms with the potential to develop biomarkers or novel therapeutic targets.

Parkinson’s disease (PD) is a chronic progressive neurodegenerative disorder, characterized by motor and non-motor signs. It was Charcot, who first in 1875 pointed out that ‘psychic faculties are definitely impaired’ and that ‘the mind becomes clouded and the memory is lost’. Most patients with PD experience some degree of cognitive impairment, ranging from mild selective deficits to Parkinson’s disease dementia (Dubois & Pillon, 1997). PD patients may also spend several years in a transition state called Mild Cognitive Impairment (MCI), which is now recognized as one of the cardinal non-motor manifestations of PD. It is a major cause of disability, and has been shown to be an important predictor for quality of life (Karlsen et al., 1998). Recent studies have reported a 21% prevalence rate of MCI in a large PD population and consider MCI as a risk factor for developing Parkinson’s disease Dementia (PDD) (Caviness et al., 2007; Janvin et al., 2006; Levin et al., 1992). The neuropathophysiological basis of cognitive deficits in PD is complicated and includes degeneration of dopaminergic neurons mainly of the nigrostriatal pathway and to a lesser degree the mesocortical and mesolimbic pathways. The striatum is closely interrelated to cortical areas mainly to the frontal lobes. The neuropathophysiological puzzle is further complicated by multiple neurotransmitter deficits including noradrenalin, serotonin and acetylcholine pathway as well as Lewy bodytype degeneration in cortical and limbic structures (Mandir & Vaughan, 2000). The direct dopaminergic connections between the ventral tegmental area and the prefrontal cortex may also influence changes in cognition (Cools 2006; Mattay et al., 2002). The pattern of cognitive impairment seen even in early PD mainly resembles that produced by frontal lobe damage, as the basal ganglia and prefrontal cortex are closely interrelated through anatomofunctional circuits (Alexander et al., 1986; Bondi et al., 1993) and include deficits mainly in cognitive flexibility, planning, working memory and learning. Perfusion brain single photon emission computed tomography (SPECT) provides a wellestablished means of studying regional cerebral blood flow (rCBF) which is known to reflect cortical function. On the other hand Dopamine Transporter (DAT) SPECT imaging can be used as a marker for the degree of loss of dopaminergic nerve endings. It is well known that SPECT Neuroimaging can assist in the differential diagnosis of parkinsonian and dementia

Patients with end-stage renal insufficiency undergoing hemodialysis show important psychiatric morbidity, particularly increased depression and anxiety. Obsessive-compulsive symptoms, however, are much less frequently investigated. The purpose of the present study was thus to assess obsessive-compulsive symptoms in hemodialysis patients.Patients treated at an outpatient hospital hemodialysis unit (July 2007) were compared with controls on scores on the Maudsley Obsessional-Compulsive Inventory (MOCI) and its checking, cleaning, slowness, and doubting components as well as on measures of emotional (Beck Depression Inventory-Fast Screen), anxiety (Beck Anxiety Inventory), and cognitive (Trail Making Test) status. Student t tests, analyses of covariance, or nonparametric tests were used. Correlations were applied between behavioral outcomes and demographic, clinical, and laboratory data of patients.Patients showed more obsessive traits than controls on the MOCI total score (P.001) and on the checking, cleaning, and doubting subscales. Significant differences between groups occurred also in Beck Depression and Anxiety Inventories (P ≤ .001). The MOCI total score did not correlate with marital status, education level, duration of hemodialysis, or the other psychological instrument scores in patients. By contrast, the MOCI total score was associated with the level of creatinine, and it showed an inverse correlation with the urea reduction ratio in patients (P.05).Obsessive-compulsive symptoms may constitute an important aspect of the psychiatric profile of patients undergoing hemodialysis. Potential interpretation involves disease- and treatment-associated factors or adaptive responses to emergence of otherwise uncontrollable stress.

Patients with multiple sclerosis (MS) have a substantial risk of cognitive dysfunction, even in the earliest stages of the disease, where there is minimum physical disability. Despite the high prevalence rates and the significant impact of cognitive dysfunction on quality of life in this population, cognitive functions are not routinely assessed due to the high cost and time consumption. This article provides an overview of the current state of knowledge related to cognition in MS and on the optimal approach to neuropsychological assessment of this population. It then focuses on the pharmacological and other treatment options available for MS patients with, or at risk for developing, cognitive impairment. The available immune-modulating agents may reduce the development of new lesions and therefore prevent or minimize the progression of cognitive decline. However, there is currently insufficient evidence concerning the efficiency of symptomatic treatment in MS. There is also currently no optimal non-pharmacological treatment strategy for cognitive decline in MS, as the studies published to date report heterogeneous results. Nevertheless, non-pharmacological treatments such as cognitive rehabilitation may benefit some MS patients. As cognition is increasingly recognized as a major feature of MS, its assessment and rehabilitation will become a greater priority.

Rationale Methadone and buprenorphine are among the most widely employed pharmacological treatments currently available for opioid addiction. Cognitive effects of buprenorphine in abstinent heroin abusers are nevertheless far from being understood. Methods Neuropsychological performance of 18 buprenorphine-maintained patients (BMP) was evaluated relative to that of 32 currently abstinent heroin abusers on naltrexone hydrochloride therapy (FHAN), and 34 non-drug dependent controls. The three groups were demographically balanced. Clinical groups reported histories of similar patterns of drug use and had increased periods of abstinence from any illicit substance use including heroin. Results The BMP group performed poorer than controls on the RAVLT (encoding and delayed recall of verbal information), CTT (conceptual flexibility, executive functions) and the RBANS figure copy (visual perception) and delayed recall of visual information. There were no significant differences in any of the cognitive measures between the BMP and FHAN groups or between the FHAN group and controls. Furthermore, the non-differing percentage of abnormal cases between the two patient groups led us to infer that treatment with either BPM or FHAN is not accompanied by qualitative differences in the cognitive profiles of these patients. Conclusion Overall, results suggest that treatment with naltrexone in abstinent heroin abusers may result in less impairment of cognitive functions compared to treatment with buprenorphine. These findings are relevant for improved prognosis and treatment strategies in opioid dependence. Copyright © 2009 John Wiley & Sons, Ltd.

We examined relationships between demographic variables and Benton Visual Retention Test performance in 352 healthy Greek adults, aged 18-84 years. We derived norms for BVRT total number correct and error scores adjusted for variables that contributed significantly to the variance. We also investigated BVRT performance in 28 acute stroke patients M = 6.14 days after insult. Age, education, and IQ, but not gender, were significantly associated with BVRT performance in healthy participants. However, only age contributed significantly to BVRT performance in acute stroke patients. Test-retest reliability was moderate (.782) for number correct and low for number error (.596) scores. Practice effects were noted only for number correct score. The test appears to discriminate adequately between acute stroke patients and matched healthy controls.

Parkinson's disease (PD) comprises a range of motor andcognitive disturbances, a portion of which respond little,if at all, to levodopa treatment and are therefore consid-ered to be due to nondopaminergic lesions [1,2]. Moresevere cognitive impairments and higher risk for develop-ing dementia have been associated with the clinical man-ifestations of postural instability and gait disorder whichare characterized by refractoriness to levodopa [2,3].

There is increasing interest in the therapeutic potential of cannabis-based medicinal extracts in multiple sclerosis. Cognitive deficits that have been attributed to long-term heavy recreational use of cannabis are not necessarily extended to controlled pharmaceutical use of cannabis-based medicinal extracts. Available data indicate that after relatively short-term administration of cannabis-based medicinal extracts no significant cognitive decline occurs. Due to the absence of large scale long-term systematic clinical trials of cannabis-based medicinal extracts in multiple sclerosis therapeutics, however, many issues remain unresolved, including the possible adverse effects of cannabis-based medicinal extracts on cognition. This article critically reviews the current literature and considers the potential for cognitive adverse effects of long-term cannabinoid use in multiple sclerosis therapeutics.

In the frame of current treatment options for multiple sclerosis (MS) and recommendations for early intervention, we investigated the practice and attitudes of neurologists towards MS-diagnosis communication in Greece. We constructed and sent out a 22-item questionnaire to neurologists practising in different employment settings and geographic regions in Greece. Overall, 217 (37.41 %) of 580 neurologists replied. The vast majority (94.9 %) informs the patient of a definite MS diagnosis, and 73.6 % do so immediately, but only 41.7 % use the term multiple sclerosis. Furthermore, neurologists strongly agreed that timing of diagnosis communication depends to a large extent on the individual patient’s personality (62.5 %) and mental state (52.3 %). Most neurologists (78.7 %) inform relatives about the diagnosis, but only in the presence of the patient. In cases where disclosure was delayed, 59.5 % noted that they did not observe any changes as regards the trust or confidence of their patients towards them. Most neurologists also noted that education level (72 %) and mental state (51.9 %), at the time of disclosure influenced patients who did not fully understand the meaning of their diagnosis. This survey provided some useful new findings with respect to MS diagnosis communication; however, the questions of how and possibly how much to communicate warrant further cross-cultural investigation.

The postural instability and gait difficulty (PIGD) motor subtype has been shown to represent a risk factor for development of dementia in Parkinson's disease. Whether this relationship extends to a more subtle cognitive dysfunction in patients is less clear. Therefore, we administered a battery of selected neuropsychological tests to two groups of non-demented patients with mild to moderate disease classified either as PIGD or as non-PIGD subtype and to a group of healthy controls. Groups were matched on potential confounders of neuropsychological performance. No significant differences were revealed between the two groups of patients in the performance of any of the administered neuropsychological tests. However, relative to controls there was a tendency towards a differential pattern of cognitive dysfunction. The PIGD group had slower performance in a test of psychomotor speed and cognitive flexibility, whilst the non-PIGD group performed worse in measures of verbal learning and visuo-spatial perception. In conclusion, the PIGD subtype was not associated with more severe cognitive deficits and may to a certain extent share common mechanisms of cognitive dysfunction with non-PIGD subtypes. Diverse pathological processes however may develop to account for unequal rates of dementia amongst different motor subtypes.

IntroductionThe issue of the association between depression and neurocognitive functions is of special interest due to the strong relation between primary depressive symptoms and cognitive impairments, but this relationship in PD is far from clear at present.ObjectivesTo examine the influence of depression on cognitive and speech performance in various stages of PD.MethodsForty four patients with PD were recruited from the neurology department, University Hospital of Patras in Greece. All patients satisfied PDSBB criteria and dementia was ruled out (MMSE < 24) in all cases. Patients were then divided into six groups, based on severity of PD symptoms and presence of depression. Stage of disease severity was determined using the Hoehn - Yahr Rating Scale. Presence and severity of depression was established using the Beck Depression Inventory and DSM -IV-TR diagnostic criteria for major depressive disorder and dysthymia. Patients were further assessed with a detailed neuropsychological battery and the dysarthria examination battery. All patients were receiving standard medications for their PD symptoms.ResultsDeficits in executive functions, prosody and speech intelligibility were most profound in the late stage depressed PD group. Phonetic impairments were most profound across all stages compared to articulatory and prosodic impairments.ConclusionsDepressed mood may exacerbate cognitive and speech impairments and affective variables should be an integral part in the treatment of PD in all stages of the disease process, but especially in the later stages.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective therapy for Parkinson’s disease (PD). Nevertheless, DBS has been associated with certain nonmotor, neuropsychiatric effects such as worsening of emotion recognition from facial expressions. In order to investigate facial emotion recognition (FER) after STN DBS, we conducted a literature search of the electronic databases MEDLINE and Web of science. In this review, we analyze studies assessing FER after STN DBS in PD patients and summarize the current knowledge of the effects of STN DBS on FER. The majority of studies, which had clinical and methodological heterogeneity, showed that FER is worsening after STN DBS in PD patients, particularly for negative emotions (sadness, fear, anger, and tendency for disgust). FER worsening after STN DBS can be attributed to the functional role of the STN in limbic circuits and the interference of STN stimulation with neural networks involved in FER, including the connections of the STN with the limbic part of the basal ganglia and pre- and frontal areas. These outcomes improve our understanding of the role of the STN in the integration of motor, cognitive, and emotional aspects of behaviour in the growing field of affective neuroscience. Further studies using standardized neuropsychological measures of FER assessment and including larger cohorts are needed, in order to draw definite conclusions about the effect of STN DBS on emotional recognition and its impact on patients’ quality of life.