Eka Chkonia

Prof. Eka Chkonia


Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 May 2018 in Scientific Reports
Verified
Journal Article
Open access
PDF file
ASAlbulena Shaqiri
Albulena Shaqiri
MRMaya Roinishvili
Maya Roinishvili
LGLukasz Grzeczkowski
Lukasz Grzeczkowski
ECEka Chkonia
Eka Chkonia
KPKarin Pilz
Karin Pilz
MHMichael H. Herzog
Michael H. Herzog
Despite well-established sex differences for cognition, audition, and somatosensation, few studies have investigated whether there are also sex differences in visual perception. We report the results of fifteen perceptual measures (such as visual acuity, visual backward masking, contrast detection threshold or motion detection) for a cohort of over 800 participants. On six of the fifteen tests, males significantly outperformed females. On no test did females significantly outperform males. Given this heterogeneity of the sex effects, it is unlikely that the sex differences are due to any single mechanism. A practical consequence of the results is that it is important to control for sex in vision research, and that findings of sex differences for cognitive measures using visually based tasks should confirm that their results cannot be explained by baseline sex differences in visual perception.

1 September 2015 in Schizophrenia Research: Cognition
Verified
Journal Article
Open access
MTMiralena I. Tomescu
Miralena I. Tomescu
TRTonia A. Rihs
Tonia A. Rihs
MRMaya Roinishvili
Maya Roinishvili
FKF. Isik Karahanoglu
F. Isik Karahanoglu
MSMaude Schneider
Maude Schneider
CCCéline Cappe
Céline Cappe
Schizophrenia is a complex psychiatric disorder and many of the factors contributing to its pathogenesis are poorly understood. In addition, identifying reliable neurophysiological markers would improve diagnosis and early identification of this disease. The 22q11.2 deletion syndrome (22q11DS) is one major risk factor for schizophrenia. Here, we show further evidence that deviant temporal dynamics of EEG microstates are a potential neurophysiological marker by showing that the resting state patterns of 22q11DS are similar to those found in schizophrenia patients. The EEG microstates are recurrent topographic distributions of the ongoing scalp potential fields with temporal stability of around 80 ms that are mapping the fast reconfiguration of resting state networks. Five minutes of high-density EEG recordings was analysed from 27 adult chronic schizophrenia patients, 27 adult controls, 30 adolescents with 22q11DS, and 28 adolescent controls. In both patient groups we found increased class C, but decreased class D presence and high transition probabilities towards the class C microstates. Moreover, these aberrant temporal dynamics in the two patient groups were also expressed by perturbations of the long-range dependency of the EEG microstates. These findings point to a deficient function of the salience and attention resting state networks in schizophrenia and 22q11DS as class C and class D microstates were previously associated with these networks, respectively. These findings elucidate similarities between individuals at risk and schizophrenia patients and support the notion that abnormal temporal patterns of EEG microstates might constitute a marker for developing schizophrenia.

24 August 2020 in European Psychiatry
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Journal Article
Open access
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DWDanuta Wasserman
Danuta Wasserman
GAGisèle Apter
Gisèle Apter
CBChris Baeken
Chris Baeken
SBS. Bailey
S. Bailey
JBJudit Balazs
Judit Balazs
SVS. Vahip
S. Vahip
Background.: Compulsory admission procedures of patients with mental disorders vary between countries in Europe. The Ethics Committee of the European Psychiatric Association (EPA) launched a survey on involuntary admission procedures of patients with mental disorders in 40 countries to gather information from all National Psychiatric Associations that are members of the EPA to develop recommendations for improving involuntary admission processes and promote voluntary care.Methods.: The survey focused on legislation of involuntary admissions and key actors involved in the admission procedure as well as most common reasons for involuntary admissions.Results.: We analyzed the survey categorical data in themes, which highlight that both medical and legal actors are involved in involuntary admission procedures.Conclusions.: We conclude that legal reasons for compulsory admission should be reworded in order to remove stigmatization of the patient, that raising awareness about involuntary admission procedures and patient rights with both patients and family advocacy groups is paramount, that communication about procedures should be widely available in lay-language for the general population, and that training sessions and guidance should be available for legal and medical practitioners. Finally, people working in the field need to be constantly aware about the ethical challenges surrounding compulsory admissions.

18 January 2012 in Schizophrenia Bulletin
Verified
Journal Article
Open access
PDF file
GPGijs Plomp
Gijs Plomp
MRMaya Roinishvili
Maya Roinishvili
ECEka Chkonia
Eka Chkonia
GKGeorge Kapanadze
George Kapanadze
MKMaia Kereselidze
Maia Kereselidze
MHMichael H. Herzog
Michael H. Herzog
Schizophrenic patients suffer from many deficits including visual, attentional, and cognitive ones. Visual deficits are of particular interest because they are at the fore-end of information processing and can provide clear examples of interactions between sensory, perceptual, and higher cognitive functions. Visual deficits in schizophrenic patients are often attributed to impairments in the dorsal (where) rather than the ventral (what) stream of visual processing. We used a visual-masking paradigm in which patients and matched controls discriminated small vernier offsets. We analyzed the evoked electroencephalography (EEG) responses and applied distributed electrical source imaging techniques to estimate activity differences between conditions and groups throughout the brain. Compared with controls, patients showed strongly reduced discrimination accuracy, confirming previous work. The behavioral deficits corresponded to pronounced decreases in the evoked EEG response at around 200 ms after stimulus onset. At this latency, patients showed decreased activity for targets in left parietal cortex (dorsal stream), but the decrease was most pronounced in lateral occipital cortex (in the ventral stream). These deficiencies occurred at latencies that reflect object processing and fine shape discriminations. We relate the reduced ventral stream activity to deficient top-down processing of target stimuli and provide a framework for relating the commonly observed dorsal stream deficiencies with the currently observed ventral stream deficiencies.

1 December 2018 in Psychiatry Research
Verified
Journal Article
Closed access
LGLukasz Grzeczkowski
Lukasz Grzeczkowski
MRMaya Roinishvili
Maya Roinishvili
ECEka Chkonia
Eka Chkonia
ABAndreas Brand
Andreas Brand
FMFred W. Mast
Fred W. Mast
ASAlbulena Shaqiri
Albulena Shaqiri

9 June 2021 in European Psychiatry
Verified
Journal Article
Open access
PDF file
MKMartina Rojnic Kuzman
Martina Rojnic Kuzman
SVSimavi Vahip
Simavi Vahip
Andrea FiorilloAndrea Fiorillo
Andrea Fiorillo
JBJulian Beezhold
Julian Beezhold
MCMariana Pinto da Costa
Mariana Pinto da Costa
Philip PAM GORWOODPhilip PAM GORWOOD
Philip PAM GORWOOD
Background: The COVID-19 pandemic caused an unprecedented worldwide crisis affecting several sectors, including health, social care, economy and society at large. The World Health Organisation has emphasized that mental health care should be considered as one of the core sectors within the overall COVID-19 health response. By March 2020, recommendations for the organization of mental health services across Europe have been developed by several national and international mental health professional associations. Methods: The European Psychiatric Association (EPA) surveyed a large European sample of psychiatrists, namely the “EPA Ambassadors”, on their clinical experience of the impact of COVID-19 pandemic on the treatment of psychiatric patients during the month of April 2020 in order to: a) identify and report the views and experiences of European psychiatrists; and b) represent and share these results with mental health policy makers at European level. Based on the recommendations issued by national psychiatric associations and on the results of our survey, we identified important organisational aspects of mental health care during the peak of the first wave of the COVID-19. Results: While most of the recommendations followed the same principles, significant differences between countries emerged in service delivery, mainly relating to referrals to outpatients and for inpatient admission, assessments and treatment for people with mental disorders. Compared to previous months, the mean number of patients treated by psychiatrists in outpatient settings halved in April 2020. In the same period, the number of mentally ill patients tested for, or developing, COVID-19 was low. In most of countries, traditional face-to-face visits were replaced by online remote consultations. Conclusions: Based on our findings we recommend: 1) to implement professional guidelines into practice and harmonize psychiatric clinical practice across Europe; 2) to monitor the treatment outcomes of patients with COVID-19 and pre-existing mental disorders; 3) to keep psychiatric services active by using all available options (for example telepsychiatry); 4) to increase communication and cooperation between different health care providers.