Acoustic-Perceptual Factors Both Maintain and Account for the Rarity of the Czech Trill-Fricative

Czech has a sibilant inventory that contrasts at three places of articulation: Alveolar, a pre-post-alveolar, and palato-alveolar. The specific aim of this study is to examine the perception of the typologically rare Czech sibilant inventory and to determine whether acoustic-perceptual characteristics play a role in the maintenance of the Czech trill-fricative. These results are compared to a more common three-way sibilant inventory, Polish. Native Czech listeners performed an auditory AX discrimination task in two blocks: A Czech block and a Polish block. Stimuli were embedded in varying levels of noise to increase task difficulty. Signal-to-noise ratio differences affected the perception of the Czech sibilants more than Polish sibilants. Moreover, a multidimensional scaling analysis revealed less perceptual dispersion for the Czech inventory than the Polish inventory. These results suggest that there is greater difficulty maintaining the Czech inventory considering the signal-to-noise comparisons and that this a factor that contributes to its rarity; however, similarities in perceptual dispersion indicate that maintenance across several acoustic-perceptual cues is possible, and Czech shows few signs of losing this typologically rare contrast.

An initial ‘snapshot’ of sensory information biases the likelihood and speed of subsequent changes of mind

We often need to rapidly change our mind about perceptual decisions in order to account for new information and correct mistakes. One fundamental, unresolved question is whether information processed prior to a decision being made (‘pre-decisional information’) has any influence on the likelihood and speed with which that decision is reversed. We investigated this using a luminance discrimination task in which participants indicated which of two flickering greyscale squares was brightest. Following an initial decision, the stimuli briefly remained on screen, and participants could change their response. Using psychophysical reverse correlation, we examined how moment-to-moment fluctuations in stimulus luminance affected participants’ decisions. This revealed that the strength of even the very earliest (pre-decisional) evidence was associated with the likelihood and speed of later changes of mind. To account for this effect, we propose an extended diffusion model in which an initial ‘snapshot’ of sensory information biases ongoing evidence accumulation.

Effects of First Language Background and Learning Experience in Perceiving Mandarin Lexical Tones: Learners and Nonlearners From English- and Japanese-Speaking Backgrounds

Purpose: This research compared individuals from two first language (L1) backgrounds (English and Japanese) to determine how they may differ in their perception of Mandarin tones (Tones 1 vs. 2 [T1–T2], Tones 1 vs. 3 [T1–T3], Tones 1 vs. 4 [T1–T4], Tones 2 vs. 3 [T2–T3], Tones 2 vs. 4 [T2–T4], Tones 3 vs. 4 [T3–T4]) on account of their L1. Method: The participants included two groups of learners of Mandarin (23 English speakers, 18 Japanese speakers), two groups of nonlearners of Mandarin (24 English speakers, 21 Japanese speakers), and a control group of 10 Mandarin speakers. A four-alternative forced-choice discrimination task that included 360 trials was presented in three blocks of 120 trials. Results: The native Mandarin group was more accurate in their tonal discrimination of all six tone pairs than all the nonnative groups. While Japanese nonlearners generally outperformed English nonlearners in their overall perception of Mandarin lexical tones, L1-based differences were less extensive for the two groups of learners. Both learner groups were least accurate on T2–T3 and most accurate on T3–T4. Conclusion: The results suggest that with classroom experience, English speakers can overcome their initial disadvantage and learn lexical tones in a new language as successfully as speakers of Japanese with classroom experience.

Match me if you can: Evidence for a domain-general visual comparison ability

Visual comparison—comparing visual stimuli (e.g., fingerprints) side by side and determining whether they originate from the same or different source (i.e., “match”)—is a complex discrimination task involving many cognitive and perceptual processes. Despite the real-world consequences of this task, which is often conducted by forensic scientists, little is understood about the psychological processes underpinning this ability. There are substantial individual differences in visual comparison accuracy amongst both professionals and novices. The source of this variation is unknown, but may reflect a domain-general and naturally varying perceptual ability. Here, we investigate this by comparing individual differences (N = 248 across two studies) in four visual comparison domains: faces, fingerprints, firearms, and artificial prints. Accuracy on all comparison tasks was significantly correlated and accounted for a substantial portion of variance (e.g., 42% in Exp. 1) in performance across all tasks. Importantly, this relationship cannot be attributed to participants’ intrinsic motivation or skill in other visual-perceptual tasks (visual search and visual statistical learning). This paper provides novel evidence of a reliable, domain-general visual comparison ability.

Attentional Orienting in Front and Rear Spaces in a Virtual Reality Discrimination Task

Recent studies on covert attention suggested that the visual processing of information in front of us is different, depending on whether the information is present in front of us or if it is a reflection of information behind us (mirror information). This difference in processing suggests that we have different processes for directing our attention to objects in front of us (front space) or behind us (rear space). In this study, we investigated the effects of attentional orienting in front and rear space consecutive of visual or auditory endogenous cues. Twenty-one participants performed a modified version of the Posner paradigm in virtual reality during a spaceship discrimination task. An eye tracker integrated into the virtual reality headset was used to make sure that the participants did not move their eyes and used their covert attention. The results show that informative cues produced faster response times than non-informative cues but no impact on target identification was observed. In addition, we observed faster response times when the target occurred in front space rather than in rear space. These results are consistent with an orienting cognitive process differentiation in the front and rear spaces. Several explanations are discussed. No effect was found on subjects’ eye movements, suggesting that participants did not use their overt attention to improve task performance.

Crosslinguistic Influence in the Discrimination of Korean Stop Contrast by Heritage Speakers and Second Language Learners

The present study examines the extent of crosslinguistic influence from English as a dominant language in the perception of the Korean lenis–aspirated contrast among Korean heritage speakers in the United States (N = 20) and English-speaking learners of Korean as a second language (N = 20), as compared to native speakers of Korean immersed in the first language environment (N = 20), by using an AX discrimination task. In addition, we sought to determine whether significant dependencies could be observed between participants’ linguistic background and experiences and their perceptual accuracy in the discrimination task. Results of a mixed-effects logistic regression model demonstrated that heritage speakers outperformed second language learners with 85% vs. 63% accurate discrimination, while no significant difference was detected between heritage speakers and first language-immersed native speakers (85% vs. 88% correct). Furthermore, higher verbal fluency was significantly predictive of greater perceptual accuracy for the heritage speakers. The results are compatible with the interpretation that the influence of English on the discrimination of the Korean laryngeal contrast was stronger for second language learners of Korean than for heritage speakers, while heritage speakers were not apparently affected by dominance in English in their discrimination of Korean lenis and aspirated stops.

The Strength of the Medial Olivocochlear Reflex in Chinchillas Is Associated With Delayed Response Performance in a Visual Discrimination Task With Vocalizations as Distractors

The ability to perceive the world is not merely a passive process but depends on sensorimotor loops and interactions that guide and actively bias our sensory systems. Understanding which and how cognitive processes participate in this active sensing is still an open question. In this context, the auditory system presents itself as an attractive model for this purpose as it features an efferent control network that projects from the cortex to subcortical nuclei and even to the sensory epithelium itself. This efferent system can regulate the cochlear amplifier sensitivity through medial olivocochlear (MOC) neurons located in the brainstem. The ability to suppress irrelevant sounds during selective attention to visual stimuli is one of the functions that have been attributed to this system. MOC neurons are also directly activated by sounds through a brainstem reflex circuit, a response linked to the ability to suppress auditory stimuli during visual attention. Human studies have suggested that MOC neurons are also recruited by other cognitive functions, such as working memory and predictability. The aim of this research was to explore whether cognitive processes related to delayed responses in a visual discrimination task were associated with MOC function. In this behavioral condition, chinchillas held their responses for more than 2.5 s after visual stimulus offset, with and without auditory distractors, and the accuracy of these responses was correlated with the magnitude of the MOC reflex. We found that the animals’ performance decreased in presence of auditory distractors and that the results observed in MOC reflex could predict this performance. The individual MOC strength correlated with behavioral performance during delayed responses with auditory distractors, but not without them. These results in chinchillas, suggest that MOC neurons are also recruited by other cognitive functions, such as working memory.

Geometric block-coherence and quantum state discrimination

Quantum coherence with respect to orthonormal bases has been studied extensively in the past few years. From the perspective of operational meaning, geometric coherence can be equal to the minimum error probability to discriminate a set of pure states [J. Phys. A: Math. Theor. 51, 414005 (2018)]. By regarding coherence as a physical resource, Baumgratz et al. [Phys. Rev. Lett. 113, 140401 (2014)] presented a comprehensive framework for coherence. Recently, geometric block-coherence as an effective block-coherence measure has been proposed. In this paper, we reveal an equivalence relationship between mixed quantum state discrimination task and geometric block-coherence, which provides an operational interpretation for geometric block-coherence and generalizes the main result in coherence resource theory. Meanwhile, we show that partial coherence is a special case of block-coherence. By linking the relationship between geometric partial coherence and quantum state discrimination tasks, we show that the value range of the two measures is the same. Finally, we reveal the relationship between geometric POVM-based coherence and quantum state discrimination task.