| 1. |
- K. Ljungberg, Jessica, et al.
(författare)
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Attention capture by tactile deviance
- 2012
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Ingår i: THULE. - : Kungliga skytteanska samfundet. - 9789186438425 ; , s. 119-132
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Bokkapitel (refereegranskat)
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| 2. |
- Körning-Ljungberg, Jessica, et al.
(författare)
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‘What’s in a name?’ ‘No more than when it's mine own’. Evidence from auditory oddball distraction
- 2014
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Ingår i: Acta Psychologica. - : Elsevier BV. - 0001-6918 .- 1873-6297. ; 150, s. 161-6
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Tidskriftsartikel (refereegranskat)abstract
- Research of the distractor value of hearing the own name has shown that this self-referring stimulus captures attention in an involuntary fashion and create distraction. The behavioral studies are few and the outcomes are not always clear cut. In this study the distraction by own name compared to a control name was investigated by using a cross-modal oddball task in two experiments. In the first experiment, thirty-nine participants were conducting a computerized categorization task while exposed to, to-be ignored own and matched control names (controlling for familiarity, gender and number of syllables) as unexpected auditory deviant stimulus (12.5% trials for each name category) and a sine wave tone as a standard stimulus (75% of the trials). In the second experiment, another group of thirty-nine participants completed the same task but with the additional deviant stimulus of an irrelevant word added (10% trials for each deviant type and 70% trials with the standard stimulus). Results showed deviant distraction by exposure to both the irrelevant word, own and the control name compared to the standard tone but no differences were found showing that the own name captured attention and distracted the participants more than an irrelevant word or a control name. The results elucidate the role of the own name as a potent auditory distractor and possible limitations with its theoretical significance for general theories of attention are discussed.
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| 3. |
- Mbufong, H. N., et al.
(författare)
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Assessing the spatial variability in peak season CO2 exchange characteristics across the Arctic tundra using a light response curve parameterization
- 2014
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Ingår i: Biogeosciences. - : Copernicus GmbH. - 1726-4189. ; 11:17, s. 4897-4912
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Tidskriftsartikel (refereegranskat)abstract
- This paper aims to assess the spatial variability in the response of CO2 exchange to irradiance across the Arctic tundra during peak season using light response curve (LRC) parameters. This investigation allows us to better understand the future response of Arctic tundra under climatic change. Peak season data were collected during different years (between 1998 and 2010) using the micrometeorological eddy covariance technique from 12 circumpolar Arctic tundra sites, in the range of 64-74 degrees N. The LRCs were generated for 14 days with peak net ecosystem exchange (NEE) using an NEE-irradiance model. Parameters from LRCs represent site-specific traits and characteristics describing the following: (a) NEE at light saturation (F-csat), (b) dark respiration (Rd), (c) light use efficiency (alpha), (d) NEE when light is at 1000 mu molm(-2) s(-1) (F-c1000), (e) potential photosynthesis at light saturation (P-sat) and (f) the light compensation point (LCP). Parameterization of LRCs was successful in predicting CO2 flux dynamics across the Arctic tundra. We did not find any trends in LRC parameters across the whole Arctic tundra but there were indications for temperature and latitudinal differences within sub-regions like Russia and Greenland. Together, leaf area index (LAI) and July temperature had a high explanatory power of the variance in assimilation parameters (F-csat, F-c1000 and P-sat), thus illustrating the potential for upscaling CO2 exchange for the whole Arctic tundra. Dark respiration was more variable and less correlated to environmental drivers than were assimilation parameters. This indicates the inherent need to include other parameters such as nutrient availability, substrate quantity and quality in flux monitoring activities.
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| 4. |
- Parmentier, Fabrice B. R., et al.
(författare)
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A behavioral study of distraction by vibrotactile novelty
- 2011
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Ingår i: Journal of Experimental Psychology. - : American Psychological Association (APA). - 0096-1523 .- 1939-1277. ; 37:4, s. 1134-1139
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Tidskriftsartikel (refereegranskat)abstract
- Past research has demonstrated that the occurrence of unexpected task-irrelevant changes in the auditory or visual sensory channels captured attention in an obligatory fashion, hindering behavioral performance in ongoing auditory or visual categorization tasks and generating orientation and re-orientation electrophysiological responses. We report the first experiment extending the behavioral study of cross-modal distraction to tactile novelty. Using a vibrotactile-visual cross-modal oddball task and a bespoke hand-arm vibration device, we found that participants were significantly slower at categorizing the parity of visually presented digits following a rare and unexpected change in vibrotactile stimulation (novelty distraction), and that this effect extended to the subsequent trial (postnovelty distraction). These results are in line with past research on auditory and visual novelty and fit the proposition of common and amodal cognitive mechanisms for the involuntary detection of change.
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| 5. |
- Parmentier, Fabrice B.R., et al.
(författare)
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Behavioral distraction by auditory novelty is not only about novelty : the role of the distracter’s informational value
- 2010
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Ingår i: Cognition. - : Elsevier BV. - 0010-0277 .- 1873-7838. ; 115:3, s. 504-511
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Tidskriftsartikel (refereegranskat)abstract
- Unexpected events often distract us. In the laboratory, novel auditory stimuli have been shown to capture attention away from a focal visual task and yield specific electrophysiological responses as well as a behavioral cost to performance. Distraction is thought to follow ineluctably from the sound’s low probability of occurrence or, put more simply, its unexpected occurrence. Our study challenges this view with respect to behavioral distraction and argues that past research failed to identify the informational value of sound as a mediator of novelty distraction. We report an experiment showing that (1) behavioral novelty distraction is only observed when the sound announces the occurrence and timing of an upcoming visual target (as is the case in all past research); (2) that no such distraction is observed for deviant sounds conveying no such information; and that (3) deviant sounds can actually facilitate performance when these, but not the standards, convey information. We conclude that behavioral novelty distraction, as observed in oddball tasks, is observed in the presence of novel sounds but only when the cognitive system can take advantage of the auditory distracters to optimize performance.
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| 6. |
- van Hardenbroek, M., et al.
(författare)
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Evidence for past variations in methane availability in a Siberian thermokarst lake based on delta C-13 of chitinous invertebrate remains
- 2013
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Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 66, s. 74-84
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Tidskriftsartikel (refereegranskat)abstract
- Understanding past methane dynamics in arctic wetlands and lakes is crucial for estimating future methane release. Methane fluxes from lake ecosystems have increasingly been studied, yet only few reconstructions of past methane emissions from lakes are available. In this study, we develop an approach to assess changes in methane availability in lakes based on delta C-13 of chitinous invertebrate remains and apply this to a sediment record from a Siberian thermokarst lake. Diffusive methane fluxes from the surface of ten newly sampled Siberian lakes and seven previously studied Swedish lakes were compared to taxon-specific delta C-13 values of invertebrate remains from lake surface sediments to investigate whether these invertebrates assimilated C-13-depleted carbon typical for methane. Remains of chironomid larvae of the tribe Orthocladiinae that, in the study lakes, mainly assimilate plant-derived carbon had higher delta C-13 than other invertebrate groups. delta C-13 of other invertebrates such as several chironomid groups (Chironomus, Chironomini, Tanytarsini, and Tanypodinae), cladocerans (Daphnia), and ostracods were generally lower. delta C-13 of Chironomini and Daphnia, and to a lesser extent Tanytarsini was variable in the lakes and lower at sites with higher diffusive methane fluxes. delta C-13 of Chironomini, Tanytarsini, and Daphnia were correlated significantly with diffusive methane flux in the combined Siberian and Swedish dataset (r = -0.72, p = 0.001, r = -0.53, p = 0.03, and r = -0.81, p < 0.001, respectively), suggesting that delta C-13 in these invertebrates was affected by methane availability. In a second step, we measured delta C-13 of invertebrate remains from a sediment record of Lake S1, a shallow thermokarst lake in northeast Siberia. In this record, covering the past ca 1000 years, delta C-13 of taxa most sensitive to methane availability (Chironomini, Tanytarsini, and Daphnia) was lowest in sediments deposited from ca AD 1250 to ca AD 1500, and after AD 1970, coinciding with warmer climate as indicated by an independent local temperature record. As a consequence the offset in delta C-13 between methane-sensitive taxa and bulk organic matter was higher in these sections than in other parts of the core. In contrast, delta C-13 of other invertebrate taxa did not show this trend. Our results suggest higher methane availability in the study lake during warmer periods and that thermokarst lakes can respond dynamically in their methane output to changing environmental conditions. (C) 2012 Elsevier Ltd. All rights reserved.
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