1,720,972 research outputs found
Habituation to onset capture via associative links with contextual information
Habituation shows organisms’ ability to ignore irrelevant repetitive stimuli, allowing attentional resources to be allocated to the relevant information. Here we investigated the role of contextual information in generating expectations that control habituation to visual onset distractors, expectations that arise from associative learning. Experiment 1 showed that the habituated capture response is restored if the onset distractor is momentarily omitted in the same context of habituation, but not if such omission is experienced in another context. Experiment 2 showed that the pre-exposure to a context in which a distractor is later encountered reduced participants’ capacity to ignore it, thus attesting a latent learning phenomenon affecting habituation of capture. Finally, Experiment 3 showed that ignoring a new distractor is easier in a context in which habituation has already taken place for a different distractor. Taken together, these results attest the context-specific nature of habituation and suggest that learning to ignore salient visual stimuli is based on expectations encoded through associative learning
Learning to ignore visual onset distractors hinges on a configuration-dependent coordinates system
Decrement of attentional capture elicited by visual onset distractors, consistent with habituation, has been extensively characterized over the past several years. However, the type of spatial frame of reference according to which such decrement occurs in the brain remains unknown. Here, four related experiments are reported to shed light on this issue. Observers were asked to discriminate the orientation of a titled line while ignoring a salient but task-irrelevant visual onset that occurred on some trials. The experiments all involved an initial habituation phase, during which capture elicited by the onset distractor progressively decreased, as in prior studies. Importantly, in all experiments, the location of the target and the distractor remained fixed during this phase. After habituation was established, in a final test phase of the various experiments, the spatial arrangement of the target and the distractor was changed to test for the relative contribution to habituation of retinotopic, spatiotopic, and configuration-dependent visual representations. Experiment 1 indicated that spatiotopic representations contribute little, if at all, to the observed decrement in attentional capture. The results from Experiment 2 were compatible with the notion that such capture reduction occurs in either retinotopic- or configuration-specific representations. However, Experiment 3 ruled out the contribution of retinotopic representations, leaving configuration-specific representation as the sole viable interpretation. This conclusion was confirmed by the results of Experiments 4 and 5. In conclusion, visual onset distractors appear to be rejected at a level of the visual hierarchy where visual events are encoded in a configuration-specific or context-dependent manner. (PsycInfo Database Record (c) 2024 APA, all rights reserved)
Processing of rhythmical acoustic patterns in the domestic chicks. A behavioral exploration
The spontaneous tendency to synchronize with a musical beat is a human universal. Recently, it has been convincingly observed also in some non-human species [1-4]. However, why synchronization ability would be present in animals is still not clear. One possibility is that synchronized behavior may have been shaped by evolution because of the predictability of rhythmic locomotion sounds [5].
In humans, organisms’ locomotion is encoded either by listening to the sound of rhythmic footsteps [6], or by the visual analysis of rhythmically walking animals described by simple point-light displays [7]. Such visual point-light displays are recognized also by non-human animals as biologically-relevant stimuli [8]. Hence, raw mechanisms for visual recognition of living organisms, available at birth and shared across species [9], could be accompanied by universal acoustic building blocks of sounds of moving animals.
To address this possibility, we presented 50 chicks (Gallus gallus) with rhythmic and a-rhythmic acoustic patterns of either 120BPM or 80BPM. In a circular semi-dark environment, 4 symmetrical speakers delivered sequentially, in circular transition, the stimuli. Chicks responded to rhythmic and a-rhythmic acoustic patterns in a comparable fashion, by following the circular presentation of the 120BPM acoustic patterns but not that of 80BPM. This result is in line with chicks’ spontaneous preference for normal rate of maternal clucking at about 120-130BPM [10] meaning that faster rhythmic and a-rhythmic patterns are both associated with recognition of living organism.
In a separate condition, chicks placed within the same experimental environment could listen to a continuous modulated sound. We observed a total diminution in motor activity. In the absence of pauses or accents defining an acoustic structure, chicks do not identify the presence of an organism that is worth following
Naïve 3-day-old domestic chicks (Gallus gallus) are attracted to discrete acoustic patterns characterizing natural vocalizations
Nonsongbirds can produce rhythmical sounds that, at times, have been shown to be meaningful in their communication. This raises the possibility that rhythm is a separate ability that might have evolved earlier than song. We asked whether nearly completely naïve domestic chicks perceive rhythm and respond in specific ways to different rhythmic patterns. To do so, specific constituent parameters of rhythmicity were used based on the sound of a natural mother hen's cluck. The sound samples created ranged from a continuous sound to articulated rhythmic patterns of alternating strong and weak events. Chicks' reactivity to the patterns was tested over a series of sound exposure experiments by their propensity to operate a running wheel toward the acoustic source, a paradigm simulating chicks' natural affiliative response to the hen's call. Results showed that motor activity increased markedly when acoustic events were discrete (compared with continuous), and significantly when accent structure was faster (compared with slower rates). Similar to human infants, chicks showed a significant preference for pulsed over continuous patterns. Chicks also ran harder toward calls with fast strong pulsating events, suggesting that different arrangements of events in time can be differently arousing, but independently of whether the events were presented in a regular or nonregular fashion
Enhanced distractor filtering in habituation contexts: Learning to ignore is easier in familiar environments
Habituation mechanisms play a pivotal role in enabling organisms to filter out irrelevant stimuli and concentrate on essential ones. Through repeated exposure, the brain learns to disregard stimuli that are irrelevant, effectively ceasing to respond to potentially distracting input. Previous studies have demonstrated that the orienting response to visual distractors disrupting visual detection tasks habituates as tasks progress and distractors are encountered repeatedly, as their initial interference diminishes. Theoretical models posit that this reduction is contingent upon the establishment of an internal representation of external stimuli. Moreover, further studies have indicated that habituation can be context- specific, suggesting that the mechanisms involved incorporate information about features of irrelevant stimuli that extend beyond their discrete characteristics. In this contribution, we further delved into the question of whether the context in which habituation occurs retains a general habituative capacity when a new, to-be-ignored stimulus is introduced. We discuss evidence indicating that the context in which habituation has already taken place facilitates the habituation process for a new stimulus. This suggests that it becomes easier to ignore new stimuli in contexts where we have already learned to disregard other stimuli, underscoring the intricate interplay between habituation, context, and attentional processes
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Temporal speed prevails on interval duration in the SNARC-like effect for tempo
The Spatial-Numerical Association of Response Codes (SNARC) effect is evidence of an association between number magnitude and response position, with faster left-key responses to small numbers and faster right-key responses to large numbers. Similarly, recent studies revealed a SNARC-like effect for tempo, defined as the speed of an auditory sequence, with faster left-key responses to slow tempo and faster right-key responses to fast tempo. In order to address some methodological issues of previous studies, in the present study we designed an experiment to investigate the occurrence of a SNARC-like effect for tempo, employing a novel procedure in which only two auditory beats in sequence with a very short interstimulus interval were used. In the "temporal speed" condition, participants were required to judge the temporal speed (slow or fast) of the sequence. In the "interval duration" condition, participants were required to judge the duration of the interval between the two beats (short or long). The results revealed a consistent SNARC-like effect in both conditions, with faster left-hand responses to slow tempo and faster right-hand responses to fast tempo. Interestingly, the consistency of the results across the two conditions indicates that the direction of the SNARC-like effect was influenced by temporal speed even when participants were explicitly required to focus on interval duration. Overall, the current study extends previous findings by employing a new paradigm that addresses potential confounding factors and strengthens evidence for the SNARC-like effect for tempo
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