Discontinuity in the enumeration of sequentially presented auditory and visual stimuli

The seeking of discontinuity in enumeration was recently renewed because Cowan [Cowan, N. (2001). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences, 24, 87–185; Cowan, N. (2005). Working memory capacity. Hove: Psychology Press] suggested that it allows evaluating the limit of the focus of attention, currently estimated at four items. A strong argument in favour of a general constraint of the cognitive system is that similar discontinuities should be observed in modalities different from the classic simultaneous presentation of visual objects. Recently, data were provided on tactile stimuli, but the authors diverged in their conclusion about the existence of such discontinuity [Gallace, A., Tan, H. Z., & Spence, C. (2006). Numerosity judgments for tactile stimuli distributed over the body surface. Perception, 35(2), 247–266; Riggs, K. J., Ferrand, L., Lancelin, D., Fryziel, L., Dumur, G., & Simpson, A. (2006). Subitizing in tactile perception. Psychological Science, 17(4), 271–272]. Following a similar rationale, our study aimed at evaluating discontinuity in the enumeration of auditory and visual stimuli presented sequentially. The clear and similar discontinuity observed in error rates, response times and given responses for both modalities favours the general capacity limit view, but also questions the size of this capacity, because the discontinuity occurred here at size 2. However, the masking of stimuli in sensory memory could not be entirely discarded.     

Contextualism and the Knowledge Norms

Epistemic contextualism is widely believed to be incompatible with the recently popular view that knowledge is the norm of assertion, practical reasoning, or belief. I argue in this article that the problems arising for contextualism from the mentioned normative views are only apparent and can be resolved by acknowledging the fairly widespread phenomenon of non‐obvious context‐sensitivity (recently embraced by even some of contextualism's most ardent former critics). Building on recent insights about non‐obvious context‐sensitivity, the article outlines an independently attractive contextualist account of the mentioned epistemic norms and provides a solution to the puzzles they give rise to in a contextualist framework.     

Learning of timing patterns and the development of temporal expectations

The present study investigated the learning of a culturally unfamiliar musical rhythm, leading to the development of temporal expectations, and it explored the potential for generalization across tempi and tasks. With that aim, we adapted the serial reaction time task to examine the learning of temporal structures by an indirect method. The temporal pattern employed was based on a complex interval ratio (2:3) and compared to one based on a simple interval ratio (1:2). In the exposure phase, non-musician participants performed a two-choice speeded discrimination task that required responding by key press to each event of the simple or complex auditory pattern. Participants were not informed about the temporal regularities; their task solely concerned the discrimination task. During exposure (Experiments 1–3), response times decreased over time for both temporal patterns, but particularly for the events following the longer interval of the more complex 2:3 pattern. Exposure further influenced performance in subsequent testing phases, notably the precision of tap timing in a production task (Experiment 2) and temporal expectations in a perception task (Experiment 3). Our findings promote the new paradigm introduced here as a method to investigate the learning of temporal structures.     

Tonal expectations influence pitch perception

In this study, we investigated the influence of tonal relatedness on pitch perception in melodies. Tonal expectations for target tones were manipulated in melodic contexts while controlling sensory expectations, thus allowing us to assess specifically the influence oftonal expectations on pitch perception. Three experimentsprovided converging evidence that tonal relatedness modulates pitch perception in nonmusician listeners. Experiment 1 showed, with a rating task, the influence of the tonal relatedness of a target tone on listeners' judgments of tuning/mistuning. Experiment 2 showed, with a priming task, that pitch processing of in-tune tones was faster for tonally related targets than for less related targets. Experiment 3 showed, with a comparison task, that discrimination performance for small mistunings was better when the to-be-compared tones were tonally related to the melodic context. Findings are discussed in relation to psychoacoustic research on contextual pitch perception and to studies showing facilitation of early processing steps via knowledge- and attention-related processes.     

Congenital amusia: A short-term memory deficit for non-verbal,but not verbal sounds

Congenital amusia refers to a lifelong disorder of music processing and is linked to pitch-processing deficits. The present study investigated congenital amusics’ short-term memory for tones, musical timbres and words. Sequences of five events (tones, timbres or words) were presented in pairs and participants had to indicate whether the sequences were the same or different. The performance of congenital amusics confirmed a memory deficit for tone sequences, but showed normal performance for word sequences. For timbre sequences, amusics’ memory performance was impaired in comparison to matched controls. Overall timbre performance was found to be correlated with melodic contour processing (as assessed by the Montreal Battery of Evaluation of Amusia). The present findings show that amusics’ deficits extend to non-verbal sound material other than pitch, in this case timbre, while not affecting memory for verbal material. This is in line with previous suggestions about the domain-specificity of congenital amusia.     

Memory decreases for prose,but not for poetry

Memory for details of text generally declines relatively rapidly, whereas memory for propositional and context-based meanings is generally more resilient over time. In the present study, we investigated short-term memory for two kinds of verbal material: prose and poetry. Participants heard or read prose stories or poems in which aphrase near the start of the passage served as a target. The text continued, and after various delays, memory was tested with a repetition of the target (old verbatim; O), a paraphrased lure (P), or a lure in which the meaning was changed. For prose, memory for surface details (as measured by O/P discrimination) declined over time (Experiments 2-4), as was expected. For poetry, memory for surface details (O/P discrimination) did not decline with increasing delay (Experiments 1, 3, and 4). This lack of decline in memory for the surface details of poetry is discussed in relation to similar results previously observed for musical excerpts (Dowling, Tillmann, & Ayers, 2001), suggesting that a particular role is played by the temporal organization and rhythmic structure of poetry andmusic.     

Influence of a tone’s tonal function on temporal change detection

Music cognition research has provided evidence that the tonal function of a musical event influences perception and memory. Our study investigated whether tonal function influences a basic temporal judgment, notably the detection of a temporal change disrupting a sequence’s regularity. The sequences consisted of six musical events presented in isochrony (or with the fifth event occurring earlier or later): Three chords (instilling a tonal context) were followed by a tone (repeated three times). The tones fulfilled one of two tonal functions in the tonal context. Participants had to detect whether the sequence contained a temporal change and were not informed about tonal manipulations. Discrimination performance (as measured by d’) showed an influence of tonal function on temporal change detection: Performance was better for the tonic tone (having the most important tonal function in the key) than for the unstable leading tone, the less stable mediant tone, and even than the stable dominant tone. The outcome shows the influence of listeners’ tonal knowledge on a perceptual time judgment and suggests that processing of tonal and temporal structures interact at some stage of processing.     

Sensitivity Actually

A number of prominent epistemologists claim that the principle of sensitivity “play[s] a starring role in the solution to some important epistemological problems” (DeRose 2010: 161; also Nozick 1981). I argue that traditional sensitivity accounts fail to explain even the most basic data that are usually considered to constitute their primary motivation. To establish this result I develop Gettier and lottery cases involving necessary truths. Since beliefs in necessary truths are sensitive by default, the resulting cases give rise to a serious explanatory problem for the defenders of sensitivity accounts. It is furthermore argued that attempts to modally strengthen traditional sensitivity accounts to avoid the problem must appeal to a notion of safety—the primary competitor of sensitivity in the literature. The paper concludes that the explanatory virtues of sensitivity accounts are largely illusory. In the framework of modal epistemology, it is safety rather than sensitivity that does the heavy explanatory lifting with respect to Gettier cases, lottery examples, and other pertinent cases.     

Implicit learning of musical timbre sequences: statistical regularities confronted with acoustical (dis)similarities

The present study investigated the influence of acoustical characteristics on the implicit learning of statistical regularities (transition probabilities) in sequences of musical timbres. The sequences were constructed in such a way that the acoustical dissimilarities between timbres potentially created segmentations that either supported (S1) or contradicted (S2) the statistical regularities or were neutral (S3). In the learning group, participants first listened to the continuous timbre sequence and then had to distinguish statistical units from new units. In comparison to a control group without the exposition phase, no interaction between sequence type and amount of learning was observed: Performance increased by the same amount for the three sequences. In addition, performance reflected an overall preference for acoustically similar timbre units. The present outcome extends previous data from the domain of implicit learning to complex nonverbal auditory material. It further suggests that listeners become sensitive to statistical regularities despite acoustical characteristics in the material that potentially affect grouping.     

Sensory versus cognitive components in harmonic priming

This study investigated the strength of sensory and cognitive components involved in musical priming. In Experiment 1, the harmonic function of the target chord and the number of pitch classes shared by the prime sequence and the target chord were manipulated. In Experiment 2, the temporal course of sensory and cognitive priming was investigated. For both musician and nonmusician listeners, cognitive priming systematically overruled sensory priming even at fast and very fast tempi (300 ms and 150 ms per chord). Cognitive priming continued to challenge sensory priming processes at extremely fast tempo (75 ms per chord) but only for participants who began the experimental session with slower tempi. This outcome suggests that the cognitive component is a fast-acting component that competes with sensory priming.