164 research outputs found
Do domestic dogs learn words based on humans’ referential behaviour?
Some domestic dogs learn to comprehend human words, although the nature and basis of this learning is unknown. In the studies presented here we investigated whether dogs learn words through an understanding of referential actions by humans rather than simple association. In three studies, each modelled on a study conducted with human infants, we confronted four word-experienced dogs with situations involving no spatial-temporal contiguity between the word and the referent; the only available cues were referential actions displaced in time from exposure to their referents. We found that no dogs were able to reliably link an object with a label based on social-pragmatic cues alone in all the tests. However, one dog did show skills in some tests, possibly indicating an ability to learn based on social-pragmatic cues
Improvement of Spatial Resolution with Staggered Arrays As Used in The Airborne Optical Sensor Ads40
Using pushbroom sensors onboard aircrafts or satellites requires, especially for photogrammetric applications, wide image swaths with a high geometric resolution. One approach to satisfy both demands is to use staggered line arrays, which are constructed from two identical CCD lines shifted against each other by half a picel in line direction. Practical applications of such arrays in remote sensing include SPOT, and in the commercial environment the Airborne Digital Sensor, or ADS40, from Leica Geosystems. Theoretically, the usefulness of staggered arrays depends from spatial reslution, which is defined by the total point spread function of the imaging system and Shannon's sampling theorem. Due to the two shifted sensor lines staggering results in a double number of sampling points perpendicular to the flight direction. In order to simultaneously double the sample number in the flight direction, the line readout rate, or integration time, has to produce half a pixel spacing on ground. Staggering in combination with a high-resolution optical system can be used to fulfil the sampling condition, which means that no spectral components above the critical spatial frequency 2/D are present. Theoretically, the resolution is as good for a non-staggered line with half pixel size D/2, but radiometric dynamics should be twice as high. In practice, the slightly different viewing angle of both lines of a staggered array can result in a deteration of image quality due to aircraft motion, attitude fluctuations or terrain undulation. Fulfilling the sampling condition further means that no aliasing occurs. This is essential for the image quality in quasiperiodical textured image areas and for photogrammetric sub-pixel accuracy. Furthermore, image restoration methods for enhancing the image quality can be applied more efficently. The panchromatic resolution of the ADS40 opties is optimised for image collection by a staggered array. This means, it transfers spatial frequencies of twice the Nyquist frequency of its 12k sensors. First experiments, which were carried out some years ago, indicated alrady a spatial resolution improvement by using image restitution the ADS 40 staggered 12k pairs. The results of the restitution algorithm, which is integrated in the ADS image processing flow, has now been analysed quantitatively. This paper presents the theory of high resolution image restitution from staggered lines and practical results with ADS40 high resolution panchromatic images and high resolution colour images, created by sharpening 12k colour images with high resolution pan-chromatic ones
Reinstatement of Cortical Outcome Representations during Higher-Order Learning
Naturalistic learning scenarios are characterized by infrequent experience of external feedback to guide behavior. Higher-order learning mechanisms like second-order conditioning (SOC) may allow stimuli that were never experienced together with reinforcement to acquire motivational value. Despite its explanatory potential for real-world learning, surprisingly little is known about the neural mechanism underlying such associative transfer of value in SOC. Here, we used multivariate cross-session, cross-modality searchlight classification on functional magnetic resonance imaging data obtained from humans during SOC. We show that visual first-order conditioned stimuli (CS) reinstate cortical patterns representing previously paired gustatory outcomes in the lateral orbitofrontal cortex (OFC). During SOC, this OFC region showed increased functional covariation with amygdala, where neural pattern similarity between second-order CS and outcomes increased from early to late stages of SOC. Our data suggest a mechanism by which motivational value is conferred to stimuli that were never paired with reinforcement
Activation of Human Auditory Cortex in Retrieval Experiments: An fMRI Study
In a previous functional magnetic resonance (fMRI) study, a subdivision of the human auditory cortex into four distinct territories was
achieved. One territory (T1a) exhibited functional specialization in terms of a foreground-background decomposition task involving matching-to-sample monitoring on tone sequences. The present study more specifically determined whether memory-guided analysis of tone sequences is part of the T1a specialization. During the encoding periods, an arbitrary and unfamiliar four-tone-sequence
(melody) played by one instrument was presented. The melody-instrument-combination was different in each period. During subsequent
retrieval periods, learned and additional combinations were presented, and the tasks were either to detect the target melodies
(experiment I) or the target instruments (experiment II). T1a showed larger activation during the melody retrieval. The results
generally suggest that (1) activation of T1a during retrieval is determined less by the sound material than by the executed task, and (2) more
specifically, that memory-guided sequential analysis in T1a is dominant over recognition of characteristic complex sounds
Menschliches Verhalten als Querschnittsthema in der BNE
Die Autor*innen entwerfen ein pädagogisches Gestaltungskonzept für das Querschnittsthema „menschliches Verhalten“ und skizzieren mögliche Elemente für Lehrveranstaltungen für angehende Lehrpersonen. (DIPF/Orig.
Examining the McGurk illusion using high-field 7 Tesla functional MRI
In natural communication speech perception is profoundly influenced by observable mouth movements. The additional visual information can greatly facilitate intelligibility but incongruent visual information may also lead to novel percepts that neither match the auditory nor the visual information as evidenced by the McGurk effect. Recent models of audiovisual (AV) speech perception accentuate the role of speech motor areas and the integrative brain sites in the vicinity of the superior temporal sulcus (STS) for speech perception. In this event-related 7 Tesla fMRI study we used three naturally spoken syllable pairs with matching AV information and one syllable pair designed to elicit the McGurk illusion. The data analysis focused on brain sites involved in processing and fusing of AV speech and engaged in the analysis of auditory and visual differences within AV presented speech. Successful fusion of AV speech is related to activity within the STS of both hemispheres. Our data supports and extends the audio-visual-motor model of speech perception by dissociating areas involved in perceptual fusion from areas more generally related to the processing of AV incongruence
Neural Mechanisms of Anaphoric Reference Revealed by fMRI
Pronouns are bound to their antecedents by matching syntactic and semantic information. The aim of this functional magnetic resonance imaging study was to localize syntactic and semantic information retrieval and integration during pronoun resolution. Especially we investigated their possible interaction with verbal working memory manipulated by distance between antecedent and pronoun. We disentangled biological and syntactic gender information using German sentences about persons (biological/syntactic gender) or things (syntactic gender) followed by congruent or incongruent pronouns. Increasing the distance between pronoun and antecedent resulted in a short and a long distance condition. Analysis revealed a language related network including inferior frontal regions bilaterally (integration), left anterior and posterior temporal regions (lexico-semantics and syntactic retrieval) and the anterior cingulate gyrus (conflict resolution) involved in pronoun resolution. Activities within the inferior frontal region were driven by Congruency (incongruent > congruent) and Distance (long > short). Temporal regions were sensitive to Distance and Congruency (but solely within long distant conditions). Furthermore, anterior temporal regions were sensitive to the antecedent type with an increased activity for person pronouns compared to thing pronouns. We suggest that activity modulations within these areas reflect the integration process of an appropriate antecedent which depends on the type of information that has to be retrieved (lexico-syntactic posterior temporal, lexico-semantics anterior temporal). It also depends on the overall syntactic and semantic complexity of long distant sentences. The results are interpreted in the context of the memory–unification-control model for sentence comprehension as proposed by Vosse and Kempen (2000), Hagoort (2005), and Snijders et al. (2009)
How Pre-Instructional Conceptions Influence learning – A Learning Process Analysis to Explore the Construction of Knowledge of the Greenhouse Effect
Im Rahmen einer explorativen video-gestützten Lernprozessstudie wurden die Veränderungen der Präkonzeptionen
über den atmosphärischen Treibhauseffekt von 13jährigen Lernenden detailliert untersucht.
Das Forschungsdesign bestand aus einer Unterrichtseinheit, die in Vor- und Nachtest-Interviews eingebettet
war. Der Unterricht basierte auf einem konstruktivistischen Lernansatz, in welchem die Entwicklung
mentaler Modelle und Vorstellungsänderungen (Conceptual Change) eine große Rolle spielen. Als Datengrundlage
dienten Transkripte der Videoaufzeichnungen, Schülerzeichnungen mit erklärenden Texten
und Interviewtranskripte, die mit qualitativen Methoden untersucht wurden. Die Analyse ergab, dass die
Lernwege der Lernenden in hohem Maße von ihrem fachspezifischen Vorwissen abhängen. Die Präkonzeptionen
der Lernenden konnten drei Präkonzepttypen zugeordnet werden: Lernende, die kein oder sehr
wenig Vorwissen über den Treibhauseffekt haben, konstruieren völlig neue mentale Modelle, die dem
durch die Instruktion vermittelten Zielmodell sehr nahe kommen. Lernende, die Vorwissen haben, das mit
grundlegenden Ideen des Zielmodells übereinstimmt, erreichen das Zielmodell durch Erweiterung und
Umstrukturierung ihrer bestehenden Wissensstrukturen. Lernenden, deren Vorwissen aus subjektivem
Weltwissen besteht, dass für sie einen größeren Erklärungswert hat, als die mit dem Unterricht vermittelten
Informationen, verändern ihre mentalen Modelle nicht erfolgreich.This paper provides an exploratory video-based learning process study that investigates in-depth the
development of 13-year old learners’ pre-instructional conceptions of the atmospheric greenhouse effect
during instruction. The research design consisted of an instructional sequence embedded in pre- and
post-test interviews. The instruction used a constructivist learning approach that focused on mental model
evolution and conceptual change. The video transcripts, the students’ annotated drawings, and the
transcripts of the interviews served as the database, which was analysed qualitatively. The analysis showed
that the learning pathways pursued by the learners significantly depend on their domain-specific previous
knowledge. The learners’ preconceptions could be typified in three preconception types: Learners,
who have no or very little previous knowledge about the greenhouse effect, build completely new mental
models that are close to the target model. Learners, who have previous knowledge that indicates compliances
with central ideas of the scientific model, reach the target model by expanding and restructuring
their existing knowledge structures. Learners whose previous knowledge consists of subjective worldly
knowledge with a greater personal explanatory value than the information conveyed through instruction
do not successfully change their existing conceptions
Interoception in insula subregions as a possible state marker for depression - an exploratory fMRI study investigating healthy, depressed and remitted participants
Background: Interoceptive awareness (iA), the awareness of stimuli originating
inside the body, plays an important role in human emotions and
psychopathology. The insula is particularly involved in neural processes
underlying iA. However, iA-related neural activity in the insula during the
acute state of major depressive disorder (MDD) and in remission from
depression has not been explored. Methods: A well-established fMRI paradigm
for studying (iA; heartbeat counting) and exteroceptive awareness (eA; tone
counting) was used. Study participants formed three independent groups:
patients suffering from MDD, patients in remission from MDD or healthy
controls. Task-induced neural activity in three functional subdivisions of the
insula was compared between these groups. Results: Depressed participants
showed neural hypo-responses during iA in anterior insula regions, as compared
to both healthy and remitted participants. The right dorsal anterior insula
showed the strongest response to iA across all participant groups. In
depressed participants there was no differentiation between different stimuli
types in this region (i.e., between iA, eA and noTask). Healthy and remitted
participants in contrast showed clear activity differences. Conclusions: This
is the first study comparing iA and eA-related activity in the insula in
depressed participants to that in healthy and remitted individuals. The
preliminary results suggest that these groups differ in there being hypo-
responses across insula regions in the depressed participants, whilst non-
psychiatric participants and patients in remission from MDD show the same
neural activity during iA in insula subregions implying a possible state
marker for MDD. The lack of activity differences between different stimulus
types in the depressed group may account for their symptoms of altered
external and internal focus
Is Our Self Nothing but Reward? Neuronal Overlap and Distinction between Reward and Personal Relevance and Its Relation to Human Personality
Background: The attribution of personal relevance, i.e. relating internal and external stimuli to establish a sense of belonging, is a common phenomenon in daily life. Although previous research demonstrated a relationship between reward and personal relevance, their exact neuronal relationship including the impact of personality traits remains unclear. Methodology/Principal Findings: Using functional magnetic resonance imaging, we applied an experimental paradigm that allowed us to explore the neural response evoked by reward and the attribution of personal relevance separately. We observed different brain regions previously reported to be active during reward and personal relevance, including the bilateral caudate nucleus and the pregenual anterior cingulate cortex (PACC). Additional analysis revealed activations in the right and left insula specific for the attribution of personal relevance. Furthermore, our results demonstrate a negative correlation between signal changes in both the PACC and the left anterior insula during the attribution of low personal relevance and the personality dimension novelty seeking. Conclusion/Significance: While a set of subcortical and cortical regions including the PACC is commonly involved in reward and personal relevance, other regions like the bilateral anterior insula were recruited specifically during personal relevance. Based on our correlation between novelty seeking and signal changes in both regions during personal relevance, we assume that the neuronal response to personally relevant stimuli is dependent on the personality trait novelty seeking.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000273104000004&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Multidisciplinary SciencesSCI(E)SSCI50ARTICLE12null
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