Feature Contribution to Motion Signal Predicted by Magnitude of Intersection-of-Constraints Projection

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 20-20
Author(s):  
L Bowns

Yo and Wilson (1992 Vision Research32 135 – 147) reported that Type II plaids move in the vector sum (VS) direction at short durations. Bowns ( Vision Research in press) showed that the result did not generalise to all Type II plaids. Computational analysis of the stimuli revealed an alternative explanation of the result in terms of features that were shown to move in a similar direction to the VS. When features (or VS) moved in a different direction to the intersection of constraints (IOC) the plaids were often perceived to move in the direction of the feature. It is hypothesised that a feature will contribute only when there is sufficient projection of the IOC in the feature direction. The direction of the features and the IOC for the stimuli used by Bowns was computed for a set of plaids that shifted from being perceived in the feature direction to the IOC. If projection is critical, then it should decrease as the stimuli shift direction. This was confirmed. A different set of plaids comprising a feature that moved in the opposite direction to the IOC and varied in terms of the magnitude of projection was presented to subjects in a forced-choice task. The plaids moved as predicted from the hypothesis. These results show a correlation between the amount of projection of the IOC in the direction of a feature and the incidence of perceived movement in the direction of the feature. The hypothesis that perceived movement of a plaid is influenced by the degree of projection of the IOC onto another available motion signal such as a displaced feature is supported.

2019 ◽  
Vol 62 (5) ◽  
pp. 1243-1257 ◽  
Author(s):  
Peggy Pik Ki Mok ◽  
Holly Sze Ho Fung ◽  
Vivian Guo Li

Purpose Previous studies showed early production precedes late perception in Cantonese tone acquisition, contrary to the general principle that perception precedes production in child language. How tone production and perception are linked in 1st language acquisition remains largely unknown. Our study revisited the acquisition of tone in Cantonese-speaking children, exploring the possible link between production and perception in 1st language acquisition. Method One hundred eleven Cantonese-speaking children aged between 2;0 and 6;0 (years;months) and 10 adolescent reference speakers participated in tone production and perception experiments. Production materials with 30 monosyllabic words were transcribed in filtered and unfiltered conditions by 2 native judges. Perception accuracy was based on a 2-alternative forced-choice task with pictures covering all possible tone pair contrasts. Results Children's accuracy of production and perception of all the 6 Cantonese tones was still not adultlike by age 6;0. Both production and perception accuracies matured with age. A weak positive link was found between the 2 accuracies. Mother's native language contributed to children's production accuracy. Conclusions Our findings show that production and perception abilities are associated in tone acquisition. Further study is needed to explore factors affecting production accuracy in children. Supplemental Material https://doi.org/10.23641/asha.7960826


2001 ◽  
Author(s):  
Markus Dressel ◽  
Teena D. Moody ◽  
Barbara J. Knowlton

Symmetry ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 279 ◽  
Author(s):  
Alex L. Jones ◽  
Bastian Jaeger

The factors influencing human female facial attractiveness—symmetry, averageness, and sexual dimorphism—have been extensively studied. However, recent studies, using improved methodologies, have called into question their evolutionary utility and links with life history. The current studies use a range of approaches to quantify how important these factors actually are in perceiving attractiveness, through the use of novel statistical analyses and by addressing methodological weaknesses in the literature. Study One examines how manipulations of symmetry, averageness, femininity, and masculinity affect attractiveness using a two-alternative forced choice task, finding that increased masculinity and also femininity decrease attractiveness, compared to unmanipulated faces. Symmetry and averageness yielded a small and large effect, respectively. Study Two utilises a naturalistic ratings paradigm, finding similar effects of averageness and masculinity as Study One but no effects of symmetry and femininity on attractiveness. Study Three applies geometric face measurements of the factors and a random forest machine learning algorithm to predict perceived attractiveness, finding that shape averageness, dimorphism, and skin texture symmetry are useful features capable of relatively accurate predictions, while shape symmetry is uninformative. However, the factors do not explain as much variance in attractiveness as the literature suggests. The implications for future research on attractiveness are discussed.


2019 ◽  
Author(s):  
Manuel Molano-Mazon ◽  
Guangyu Robert Yang ◽  
Ainhoa Hermoso-Mendizabal ◽  
Jaime de la Rocha

2021 ◽  
Vol 922 (2) ◽  
pp. 265
Author(s):  
J. Larsson ◽  
J. Sollerman ◽  
J. D. Lyman ◽  
J. Spyromilio ◽  
L. Tenhu ◽  
...  

Abstract The distribution of ejecta in young supernova remnants offers a powerful observational probe of their explosions and progenitors. Here we present a 3D reconstruction of the ejecta in SNR 0540-69.3, which is an O-rich remnant with a pulsar wind nebula located in the LMC. We use observations from the Very Large Telescope (VLT)/MUSE to study Hβ, [O iii] λ λ4959, 5007, Hα, [S ii] λ λ6717, 6731, [Ar iii] λ7136, and [S iii] λ9069. This is complemented by 2D spectra from VLT/X-shooter, which also cover [O ii] λ λ3726, 3729, and [Fe ii] λ12567. We identify three main emission components: (i) clumpy rings in the inner nebula (≲1000 km s−1) with similar morphologies in all lines; (ii) faint extended [O iii] emission dominated by an irregular ring-like structure with radius ∼1600 km s−1 and inclination ∼40°, but with maximal velocities reaching ∼3000 km s−1; and (iii) a blob of Hα and Hβ located southeast of the pulsar at velocities ∼1500–3500 km s−1. We analyze the geometry using a clump-finding algorithm and use the clumps in the [O iii] ring to estimate an age of 1146 ± 116 yr. The observations favor an interpretation of the [O iii] ring as ejecta, while the origin of the H-blob is more uncertain. An alternative explanation is that it is the blown-off envelope of a binary companion. From the detection of Balmer lines in the innermost ejecta we confirm that SNR 0540 was a Type II supernova and that hydrogen was mixed down to low velocities in the explosion.


2018 ◽  
Vol 45 (5) ◽  
pp. 1054-1072 ◽  
Author(s):  
Jessica F. SCHWAB ◽  
Casey LEW-WILLIAMS ◽  
Adele E. GOLDBERG

AbstractChildren tend to regularize their productions when exposed to artificial languages, an advantageous response to unpredictable variation. But generalizations in natural languages are typically conditioned by factors that children ultimately learn. In two experiments, adult and six-year-old learners witnessed two novel classifiers, probabilistically conditioned by semantics. Whereas adults displayed high accuracy in their productions – applying the semantic criteria to familiar and novel items – children were oblivious to the semantic conditioning. Instead, children regularized their productions, over-relying on only one classifier. However, in a two-alternative forced-choice task, children's performance revealed greater respect for the system's complexity: they selected both classifiers equally, without bias toward one or the other, and displayed better accuracy on familiar items. Given that natural languages are conditioned by multiple factors that children successfully learn, we suggest that their tendency to simplify in production stems from retrieval difficulty when a complex system has not yet been fully learned.


2020 ◽  
Vol 287 (1929) ◽  
pp. 20201148
Author(s):  
Roza G. Kamiloğlu ◽  
Katie E. Slocombe ◽  
Daniel B. M. Haun ◽  
Disa A. Sauter

Vocalizations linked to emotional states are partly conserved among phylogenetically related species. This continuity may allow humans to accurately infer affective information from vocalizations produced by chimpanzees. In two pre-registered experiments, we examine human listeners' ability to infer behavioural contexts (e.g. discovering food) and core affect dimensions (arousal and valence) from 155 vocalizations produced by 66 chimpanzees in 10 different positive and negative contexts at high, medium or low arousal levels. In experiment 1, listeners ( n = 310), categorized the vocalizations in a forced-choice task with 10 response options, and rated arousal and valence. In experiment 2, participants ( n = 3120) matched vocalizations to production contexts using yes/no response options. The results show that listeners were accurate at matching vocalizations of most contexts in addition to inferring arousal and valence. Judgments were more accurate for negative as compared to positive vocalizations. An acoustic analysis demonstrated that, listeners made use of brightness and duration cues, and relied on noisiness in making context judgements, and pitch to infer core affect dimensions. Overall, the results suggest that human listeners can infer affective information from chimpanzee vocalizations beyond core affect, indicating phylogenetic continuity in the mapping of vocalizations to behavioural contexts.


2020 ◽  
pp. 002383092097184
Author(s):  
Jeremy Steffman ◽  
Hironori Katsuda

Recent research has proposed that listeners use prosodic information to guide their processing of phonemic contrasts. Given that prosodic organization of the speech signal systematically modulates durational patterns (e.g., accentual lengthening and phrase-final (PF) lengthening), listeners’ perception of durational contrasts has been argued to be influenced by prosodic factors. For example, given that sounds are generally lengthened preceding a prosodic boundary, listeners may adjust their perception of durational cues accordingly, effectively compensating for prosodically-driven temporal patterns. In the present study we present two experiments designed to test the importance of pitch-based cues to prosodic structure for listeners’ perception of contrastive vowel length (CVL) in Tokyo Japanese along these lines. We tested if, when a target sound is cued as being PF, listeners compensatorily adjust categorization of vowel duration, in accordance with PF lengthening. Both experiments were a two-alternative forced choice task in which listeners categorized a vowel duration continuum as a phonemically short or long vowel. We manipulated only pitch surrounding the target sound in a carrier phrase to cue it as intonational phrase final, or accentual phrase medial. In Experiment 1 we tested perception of an accented target word, and in Experiment 2 we tested perception of an unaccented target word. In both experiments, we found that contextual changes in pitch influenced listeners’ perception of CVL, in accordance with their function as signaling intonational structure. Results therefore suggest that listeners use tonal information to compute prosodic structure and bring this to bear on their perception of durational contrasts in speech.


2020 ◽  
Vol 47 (6) ◽  
pp. 1132-1169
Author(s):  
Meghan ARMSTRONG

AbstractThis study explores how young children infer nuances in epistemic modality through prosody. A forced-choice task was used, testing children's (ages three to seven) comprehension of the might/will distinction (modal condition) as well their ability to modulate the strength of might through two prosodic tunes (prosody condition). Positive and negative valence conditions were included. Younger children were shown to start off performing above chance for the modal condition, and at around chance for the prosody condition, but after age four performance on the prosody condition quickly improved. For both modal verbs and prosody, children performed significantly better when valence was positive. By age seven, children performed at ceiling for all conditions. Qualitative analysis of children's justifications for prosody responses showed metalinguistic awareness of prosodic meaning as early as age four, with the ability to relate prosody to epistemic modal meaning becoming quite common by age seven.


Behaviour ◽  
2019 ◽  
Vol 156 (13-14) ◽  
pp. 1283-1307 ◽  
Author(s):  
Jay W. Schwartz ◽  
Harold Gouzoules

Abstract Screams are phylogenetically widespread and typically associated with emotionally intense contexts, and thus present a window into the evolution of vocal emotion expression. Screams are distinct from other vocalizations, but nonetheless exhibit acoustic variation. The purpose of this study was to assess whether humans are sensitive to this variation, specifically, whether they base perceptions of screamer arousal on the pitch and/or duration of screams. A forced choice task revealed a significant tendency to perceive longer or higher-pitched (but otherwise acoustically identical) screams as more emotionally intense than shorter or lower-pitched screams, respectively. This pattern was independent of participants’ gender, empathy score, and previous exposure to screams in the media. Furthermore, scream pairs exhibiting greater differences in duration yielded more consistent responses. Evolutionary implications relating to the acoustic correlates of arousal across mammalian species, as well as the socioecological functions of screams in other primates, are discussed.


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