Franco Delogu

Influence of musical expertise on segmental and tonal processing in mandarin chinese

A same–different task was used to test the hypothesis that musical expertise improves the discrimination of tonal and segmental (consonant, vowel) variations in a tone language, Mandarin Chinese. Two four-word sequences (prime and target) were presented to French musicians and nonmusicians unfamiliar with Mandarin, and event-related brain potentials were recorded. Musicians detected both tonal and segmental variations more accurately than nonmusicians. Moreover, tonal variations were associated with higher error rate than segmental variations and elicited an increased N2/N3 component that developed 100 msec earlier in musicians than in nonmusicians. Finally, musicians also showed enhanced P3b components to both tonal and segmental variations. These results clearly show that musical expertise influenced the perceptual processing as well as the categorization of linguistic contrasts in a foreign language. They show positive music-to-language transfer effects and open new perspectives for the learning of tone languages.

From melody to lexical tone: Musical ability enhances specific aspects of foreign language perception

Previous research shows that music ability provides positive effects on language processing. This study aims at better clarifying the involvement of different linguistic subdomains in this cross-domain link, assessing whether or not musicality and music expertise enhance phonological and lexical tone processing of Mandarin Chinese. In two experiments different groups of adults and children with no previous experience in tonal languages, were invited to perform a same–different task trying to detect phonological and tonal variations in pairs of sequences of monosyllabic Mandarin Chinese words. Main results show that all subjects perform significantly better in detecting phonological variations rather than tonal ones. They also show that both melodic proficiency and music expertise are good predictors for a better tonal, but not phonological identification. Data lead to a model of music-to-language transfer effect in which musicality selectively affects linguistic intonation while leaving phonological processing substantially unaffected.

Audio-visual crossmodal interactions in environmental perception: an fMRI investigation

In everyday life, the perception of surrounding events rarely takes place through a single sensory modality. Rather, perception is the result of the processing of information converging from the different senses. Behavioural research often proposes that the binding of different kinds of sensory input creates advantages in the detection, localization, and recognition of external events (King and Calvert 2001). However, the modalities with which multiple sensory cues deriving from the same object merge to form a coherent precept still represent a controversial topic in literature. Research in this field, from the animal studies of Stein and Meredith (1993) to the latest human neuroimaging investigations (for a review see Calvert 2001), has shown the importance of the temporal and spatial congruence of incoming stimuli in establishing crossmodal associations. Nevertheless, other characteristics, like semantic congruence, play a significant role in binding crossmodal associations, especially during the integration of information about complex objects. Thus the analysis of the semantic relationships established in crossmodal stimulation may be a promising instrument for exploring the neural substrates of multi-sensory integration. At least two main theoretical views on the neural pathways involved in crossmodal processing have been proposed: the first one stresses the importance of multisensory cortical areas that receive projections from the different senses (Calvert 2001); the second view emphasizes the importance of the combined activity of the modality-specific cortices by means of synchronized firing (Ettlinger and Wilson 1990). At the same time, an effort has been made to identify regions of the human brain, called heteromodal cortices, that receive afferents from different senses and are analogous to those described in animals. At the cortical level, these regions have been found in the superior temporal sulcus, in the intraparietal sulcus, and in the prefrontal and limbic cortices (Mesulam 1998; Calvert 2001). Heteromodal areas have also been found in subcortical structures, such as the superior colliculus (Stein and Meredith 1993). Recent neuroimaging investigations attempted to establish a relationship between different crossmodal tasks and the activation of specific heteromodal areas (Calvert 2001). Experimental evidence reported the activation of the lateral temporal cortex in response to the integration of audio-visual information during recognition or identification tasks, as described by Calvert et al. (2000). These authors investigated the regions that exhibited supraadditive response enhancement to congruent audiovisual speech using functional magnetic resonance imaging (fMRI). They observed strong interaction effects in the left superior temporal sulcus. Recently, Beauchamp et al. (2004) investigated the contribution of the superior temporal areas in the integration of visual and auditory information about Cogn Process (2004) 5: 167–174 DOI 10.1007/s10339-004-0024-0

Music-to-language transfer effect: may melodic ability improve learning of tonal languages by native nontonal speakers?

In tonal languages, as Mandarin Chinese and Thai, word meaning is partially determined by lexical tones. Previous studies suggest that lexical tones are processed by native listeners as linguistic information and not as pure tonal information. This study aims at verifying if, in nontonal languages speakers, the discrimination of lexical Mandarin tones varies in function of the melodic ability. Forty-six students with no previous experience of Mandarin or any other tonal language were presented with two short lists of spoken monosyllabic Mandarin words and invited to perform a same–different task trying to identify whether the variation were phonological or tonal. Main results show that subjects perform significantly better in identifying phonological variations rather than tonal ones and interestingly, the group with a high melodic ability (assessed by Wing subtest 3) shows a better performance exclusively in detecting tonal variations.

Semantic encoding in working memory: Is there a (multi)modality effect?

In spite of a large body of empirical research demonstrating the importance of multisensory integration in cognition, there is still little research about multimodal encoding and maintenance effects in working memory. In this study we investigated multimodal encoding in working memory by means of an immediate serial recall task with different modality and format conditions. In a first non-verbal condition participants were presented with sequences of non-verbal inputs representing familiar (concrete) objects, either in visual, auditory or audio-visual formats. In a second verbal condition participants were presented with written, spoken, or bimodally presented words denoting the same objects represented by pictures or sounds in the non-verbal condition. The effects of articulatory suppression were assessed in both conditions. We found a bimodal superiority effect on memory span with non-verbal material, and a larger span with auditory (or bimodal) versus visual presentation with verbal material, with a significant effect of articulatory suppression in the two conditions.

eCorsi: implementation and testing of the Corsi block-tapping task for digital tablets.

The Corsi block-tapping task is a widely used test to assess visuo-spatial working memory. The test is traditionally administered using nine square blocks positioned on a wooden board, but numerous digital versions have been developed. In this study, we tested one-hundred and seven participants divided into two age groups (18–30 and over 50) in forward, backward and supraspan-forward conditions with eCorsi, a tablet version of the Corsi task. Compared to the traditional physical board, eCorsi has several advantages, including: simple installation, set-up, and use; considerably increased accuracy in presentation timing, automatic measures of span and reaction times, in both the forward and backward response modalities. Results showed that average span and error rates were essentially analogous to the ones obtained in the main standardization studies, which have used the original physical version of the Corsi test. Furthermore, timing results provide new indications about the mechanisms underlying spatial sequence processing, suggesting that the subjects response is not planned during sequence presentation, but between the end of the presentation and the beginning of the response.

Binding "when" and "where" impairs temporal, but not spatial recall in auditory and visual working memory

Information about where and when events happen seem naturally linked to each other, but only few studies have investigated whether and how they are associated in working memory. We tested whether the location of items and their temporal order are jointly or independently encoded. We also verified if spatio-temporal binding is influenced by the sensory modality of items. Participants were requested to memorize the location and/or the serial order of five items (environmental sounds or pictures sequentially presented from five different locations). Next, they were asked to recall either the item location or their order of presentation within the sequence. Attention during encoding was manipulated by contrasting blocks of trials in which participants were requested to encode only one feature to blocks of trials where they had to encode both features. Results show an interesting interaction between task and attention. Accuracy in serial order recall was affected by the simultaneous encoding of item location, whereas the recall of item location was unaffected by the concurrent encoding of the serial order of items. This asymmetric influence of attention on the two tasks was similar for the auditory and visual modality. Together, these data indicate that item location is processed in a relatively automatic fashion, whereas maintaining serial order is more demanding in terms of attention. The remarkably analogous results for auditory and visual memory performance, suggest that the binding of serial order and location in working memory is not modality-dependent, and may involve common intersensory mechanisms.

Perceptual preferences in depth stratification of transparent layers: Photometric and non-photometric factors.

In three experiments, using a two-alternative forced-choice task, we obtained depth judgments of displays containing transparent regions. The regions varied in lightness, size, and animation. Observers nearly always strongly preferred one certain depth ordering among the regions, even though their lightness conditions were expected to give rise to ambiguity among possible orderings. This expectation was based on the contrast polarity model, which expects ambiguity in the absence of contrast polarity reversal. The expectation was founded also on a stronger condition based on the transmittance anchoring principle, which gives preference to the largest lightness contrast between regions. In the absence of contrast polarity reversal and in conditions of balanced regional contrast, preferences were shown to depend on additional conditions of contrast between two respective regions and their overlap. Depth ordering judgment seems to be based on a critical decision threshold, independently of the coordinate system used to specify lightness. We also investigated the role of non-photometric factors such as motion and relative size, and concluded that these variables can modulate depth ordering judgments in transparency.

Encoding location and serial order in auditory working memory: evidence for separable processes

In this study, we investigated the interactions between temporal and spatial information in auditory working memory. In two experiments, participants were presented with sequences of sounds originating from different locations in space and were then asked to recall either their position or their serial order. In Experiment 1, attention during encoding was manipulated by contrasting ‘pure’ blocks (i.e., location-only or serial-order-only trials) to ‘mixed’ blocks (i.e., different percentages of spatial and serial-order trials). In Experiment 2, ‘pure’ blocks were contrasted to blocks in which spatial and serial-order trials were intermixed with a third task requiring a semantic categorization of sounds. Results from both experiments showed that, whereas serial-order recall is linearly affected by the simultaneous encoding of a concurrent feature, the recall of position is mostly unaffected by concurrent feature encoding. Contrastingly, overall performance level was lower for spatial recall than serial recall. We concluded that serial order and location of items appear to be independently encoded in auditory working memory. Serial order is easier to recall, but strongly affected by the processing of concurrent item dimensions, while item location is more difficult to recall, but relatively automatic, as shown by its strong resistance to interfering dimensions in encoding.

Binding “what” and “where” in auditory working memory: An asymmetrical association between sound identity and sound location

Contrasting results in visual and auditory working memory studies suggest that the mechanisms of association between location and identity of stimuli depend on the sensory modality of the input. In this auditory study, we tested whether the association of two features both encoded in the “what” stream is different from the association between a “what” and a “where” feature. In an old–new recognition task, blindfolded participants were presented with sequences of sounds varying in timbre, pitch and location. They were required to judge if either the timbre, pitch or location of a single-probe stimulus was identical or different to the timbre, pitch or location of one of the sounds of the previous sequence. Only variations in one of the three features were relevant for the task, whereas the other two features could vary, with task-irrelevant changes. Results showed that task-irrelevant variations in the “what” features (either timbre or pitch) caused an impaired recognition of sound location and in the other task-relevant “what” feature, whereas changes in sound location did not affect the recognition of either one of the “what” features. We conclude that the identity of sounds is incidentally processed even when not required by the task, whereas sound location is not maintained when task irrelevant.