Omar I Johannesson

Dr. Omar I Johannesson


Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

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

Representative Publications

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1 March 2016 in I-Perception
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Journal Article
Open access
OJOmar I Johannesson
Omar I Johannesson
ITIan M. Thornton
Ian M. Thornton
ISIrene J. Smith
Irene J. Smith
ACAndrey Chetverikov
Andrey Chetverikov
ÁKÁrni Kristjánsson
Árni Kristjánsson
A popular model of the function of selective visual attention involves search where a single target is to be found among distractors. For many scenarios, a more realistic model involves search for multiple targets of various types, since natural tasks typically do not involve a single target. Here we present results from a novel multiple-target foraging paradigm. We compare finger foraging where observers cancel a set of predesignated targets by tapping them, to gaze foraging where observers cancel items by fixating them for 100 ms. During finger foraging, for most observers, there was a large difference between foraging based on a single feature, where observers switch easily between target types, and foraging based on a conjunction of features where observers tended to stick to one target type. The pattern was notably different during gaze foraging where these condition differences were smaller. Two conclusions follow: (a) The fact that a sizeable number of observers (in particular during gaze foraging) had little trouble switching between different target types raises challenges for many prominent theoretical accounts of visual attention and working memory. (b) While caveats must be noted for the comparison of gaze and finger foraging, the results suggest that selection mechanisms for gaze and pointing have different operational constraints.

29 October 2018 in European Journal of Neuroscience
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Journal Article
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OJOmar I Johannesson
Omar I Johannesson
JTJérôme Tagu
Jérôme Tagu
AKArni Kristjansson
Arni Kristjansson

27 June 2016 in Brain Sciences
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Journal Article
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OJOmar I Johannesson
Omar I Johannesson
Oana MitruțOana Mitruț
Oana Mitruț
RURunar Unnthorsson
Runar Unnthorsson
Alin Dragoș Bogdan MoldoveanuAlin Dragoș Bogdan Moldoveanu
Alin Dragoș Bogdan Moldoveanu
AKArni Kristjansson
Arni Kristjansson
The Sound of Vision project involves developing a sensory substitution device that is aimed at creating and conveying a rich auditory representation of the surrounding environment to the visually impaired. However, the feasibility of such an approach is strongly constrained by neural flexibility, possibilities of sensory substitution and adaptation to changed sensory input. We review evidence for such flexibility from various perspectives. We discuss neuroplasticity of the adult brain with an emphasis on functional changes in the visually impaired compared to sighted people. We discuss effects of adaptation on brain activity, in particular short-term and long-term effects of repeated exposure to particular stimuli. We then discuss evidence for sensory substitution such as Sound of Vision involves, while finally discussing evidence for adaptation to changes in the auditory environment. We conclude that sensory substitution enterprises such as Sound of Vision are quite feasible in light of the available evidence, which is encouraging regarding such projects.

15 January 2016 in Journal of Translational Medicine
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Journal Article
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Sorin HostiucSorin Hostiuc
Sorin Hostiuc
Alin Dragoș Bogdan MoldoveanuAlin Dragoș Bogdan Moldoveanu
Alin Dragoș Bogdan Moldoveanu
Maria-Iuliana DascaluMaria-Iuliana Dascalu
Maria-Iuliana Dascalu
RURunar Unnthorsson
Runar Unnthorsson
OJOmar I Johannesson
Omar I Johannesson
IMIoan Marcus
Ioan Marcus
Translational research tries to apply findings from basic science to enhance human health and well-being. Many phases of the translational research may include non-medical tasks (information technology, engineering, nanotechnology, biochemistry, animal research, economy, sociology, psychology, politics, and so on). Using common bioethics principles to these areas might sometimes be not feasible, or even impossible. However, the whole process must respect some fundamental, moral principles. The purpose of this paper is to argument the need for a different approach to the morality in translational bioethics, and to suggest some directions that might be followed when constructing such a bioethics. We will show that a new approach is needed and present a few ethical issues that are specific to the translational research.

28 March 2012 in Experimental Brain Research
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OJOmar I Johannesson
Omar I Johannesson
ÁÁÁrni Gunnar Ásgeirsson
Árni Gunnar Ásgeirsson
ÁKÁrni Kristjánsson
Árni Kristjánsson

30 March 2013 in Experimental Brain Research
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Journal Article
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OJOmar I Johannesson
Omar I Johannesson
ÁKÁrni Kristjánsson
Árni Kristjánsson