Nadejda Bocheva

Dr. Nadejda Bocheva

Institute of Neurobiology, Bulgarian Academy of Sciences, Sofia, Bulgaria
orcid

Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

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

Representative Publications

View All Publications
28 February 2018 in International Journal of Online and Biomedical Engineering (iJOE)
Verified
Journal Article
Open access
PDF file
Radoslava Stankova KralevaRadoslava Stankova Kraleva
Radoslava Stankova Kraleva
Velin Spasov KralevVelin Spasov Kralev
Velin Spasov Kralev
NSNina Sinyagina
Nina Sinyagina
Petia Koprinkova-HristovaPetia Koprinkova-Hristova
Petia Koprinkova-Hristova
NBNadejda Bocheva
Nadejda Bocheva
In this paper, the results of a comparative analysis between different approaches to experimental data storage and processing are presented. Several studies related to the problem and some methods for solving it have been discussed. Different types of databases, ways of using them and the areas of their application are analyzed. For the purposes of the study, a relational database for storing and analyzing a specific data from behavioral experiments was designed. The methodology and conditions for conducting the experiments are described. Three different indicators were analyzed, respectively: memory required to store the data, time to load the data from an external file into computer memory and iteration time across all records through one cycle. The obtained results show that for storing a large number of records (in the order of tens of millions of rows), either dynamic arrays (stored on external media in binary file format), or an approach based on a local or remote database management system can be used. Regarding the data loading time, the fastest approach was the one that uses dynamic arrays. It outperforms significantly the approaches based on a local or remote database. The obtained results show that the dynamic arrays and the local data sets approaches iterated much faster across all data records than the remote database approach. The paper concludes with proposal for further developments towards using of web services.

1 October 1993 in Vision Research
Verified
Journal Article
Closed access
PVPiet G. Vos
Piet G. Vos
NBNadejda Bocheva
Nadejda Bocheva
NYNaum Yakimoff
Naum Yakimoff
EHEric Helsper
Eric Helsper

26 May 2013 in Experimental Brain Research
Verified
Journal Article
Closed access
PDF file
NBNadejda Bocheva
Nadejda Bocheva
DADonka Angelova
Donka Angelova
MSMiroslava Stefanova
Miroslava Stefanova

5 April 2019 in Frontiers in Computational Neuroscience
Verified
Journal Article
Open access
PDF file
Petia Koprinkova-HristovaPetia Koprinkova-Hristova
Petia Koprinkova-Hristova
NBNadejda Bocheva
Nadejda Bocheva
SNSimona Nedelcheva
Simona Nedelcheva
MSMirsolava Stefanova
Mirsolava Stefanova
The paper presents a hierarchical spike timing neural network model developed in NEST simulator aimed to reproduce human decision making in simplified simulated visual navigation tasks. It includes multiple layers starting from retina photoreceptors and retinal ganglion cells (RGC) via thalamic relay including lateral geniculate nucleus (LGN), thalamic reticular nucleus (TRN), and interneurons (IN) mediating connections to the higher brain areas—visual cortex (V1), middle temporal (MT), and medial superior temporal (MTS) areas, involved in dorsal pathway processing of spatial and dynamic visual information. The last layer—lateral intraparietal cortex (LIP)—is responsible for decision making and organization of the subsequent motor response (saccade generation). We simulated two possible decision options having LIP layer with two sub-regions with mutual inhibitory connections whose increased firing rate corresponds to the perceptual decision about motor response—left or right saccade. Each stage of the model was tested by appropriately chosen stimuli corresponding to its selectivity to specific stimulus characteristics (orientation for V1, direction for MT, and expansion/contraction movement templates for MST, respectively). The overall model performance was tested with stimuli simulating optic flow patterns of forward self-motion on a linear trajectory to the left or to the right from straight ahead with a gaze in the direction of heading.

4 July 2019 in Neural Computing and Applications
Verified
Journal Article
Closed access
PDF file
Petia Koprinkova-HristovaPetia Koprinkova-Hristova
Petia Koprinkova-Hristova
MSMiroslava Stefanova
Miroslava Stefanova
BGBilyana Genova
Bilyana Genova
NBNadejda Bocheva
Nadejda Bocheva
Radoslava Stankova KralevaRadoslava Stankova Kraleva
Radoslava Stankova Kraleva
Velin Spasov KralevVelin Spasov Kralev
Velin Spasov Kralev

30 September 2018 in International Journal of Online and Biomedical Engineering (iJOE)
Verified
Journal Article
Open access
PDF file
Velin Spasov KralevVelin Spasov Kralev
Velin Spasov Kralev
Radoslava Stankova KralevaRadoslava Stankova Kraleva
Radoslava Stankova Kraleva
NSNinа Sinyagina
Ninа Sinyagina
Petia Koprinkova-HristovaPetia Koprinkova-Hristova
Petia Koprinkova-Hristova
NBNadejda Bocheva
Nadejda Bocheva
This paper presents the results obtained from a comparative analysis of two methods for experimental data sharing. Several works related to the topic and some approaches for processing data have been discussed. Different technolgoies related to the web services, ways of using them and the areas of their application are analyzed. For the purposes of the study, a web service for retrieving specific data from a behavioral experiments database was developed.The methodology and conditions for conducting the experiments are described. Two different indicators are analyzed, respectively: time to retrieve the data from a database and iteration time across all records through one loop. The results show that when retrieving thousands of records both web service based approach and an approach based on a remote database server can be used. However, when retrieving millions of records, the fastest approach was the one that uses remote database server. The obtainedresultsshow that the dynamic arrays (containing strings) iterated much faster across all data records than the dataset approach.