Régine Kolinsky

How Learning to Read Changes the Cortical Networks for Vision and Language

Reading, Writing, and Face Recognition Reading, not to mention writing and texting, is a relatively recent invention, and hence it is believed that a preliterate brain must adapt on the fly, so to speak, in learning how to process written words, rather than being able to rely upon evolutionarily ancient modifications of the visual system pathways. Dehaene et al. (p. 1359, published online 11 November) examined the neural response to a range of visual stimuli in three groups: illiterate adults, adults who learned to read as children, and adults who learned to read as adults. Reading induced a greater facility in processing horizontally oriented stimuli at early stages in the visual pathway and was also associated with the appearance of an area specialized for words. This gain of function appeared to occur at a cost—the area in the temporal cortex devoted to face processing shrank. Reading changes the mind. Does literacy improve brain function? Does it also entail losses? Using functional magnetic resonance imaging, we measured brain responses to spoken and written language, visual faces, houses, tools, and checkers in adults of variable literacy (10 were illiterate, 22 became literate as adults, and 31 were literate in childhood). As literacy enhanced the left fusiform activation evoked by writing, it induced a small competition with faces at this location, but also broadly enhanced visual responses in fusiform and occipital cortex, extending to area V1. Literacy also enhanced phonological activation to speech in the planum temporale and afforded a top-down activation of orthography from spoken inputs. Most changes occurred even when literacy was acquired in adulthood, emphasizing that both childhood and adult education can profoundly refine cortical organization.

Spatial associations for musical stimuli: A piano in the head?

This study was aimed at examining whether pitch height and pitch change are mentally represented along spatial axes. A series of experiments explored, for isolated tones and 2-note intervals, the occurrence of effects analogous to the spatial numerical association of response codes (SNARC) effect. Response device orientation (horizontal vs. vertical), task, and musical expertise of the participants were manipulated. The pitch of isolated tones triggered the automatic activation of a vertical axis independently of musical expertise, but the contour of melodic intervals did not. By contrast, automatic associations with the horizontal axis seemed linked to music training for pitch and, to a lower extent, for intervals. These results, discussed in the light of studies on number representation, provide a new example of the effects of musical expertise on music cognition.

Songs as an aid for language acquisition

In previous research, Saffran and colleagues [Saffran, J. R., Aslin, R. N., & Newport, E. L. (1996). Statistical learning by 8-month-old infants. Science, 274, 1926-1928; Saffran, J. R., Newport, E. L., & Aslin, R. N. (1996). Word segmentation: The role of distributional cues. Journal of Memory and Language, 35, 606-621.] have shown that adults and infants can use the statistical properties of syllable sequences to extract words from continuous speech. They also showed that a similar learning mechanism operates with musical stimuli [Saffran, J. R., Johnson, R. E. K., Aslin, N., & Newport, E. L. (1999). Abstract Statistical learning of tone sequences by human infants and adults. Cognition, 70, 27-52.]. In this work we combined linguistic and musical information and we compared language learning based on speech sequences to language learning based on sung sequences. We hypothesized that, compared to speech sequences, a consistent mapping of linguistic and musical information would enhance learning. Results confirmed the hypothesis showing a strong learning facilitation of song compared to speech. Most importantly, the present results show that learning a new language, especially in the first learning phase wherein one needs to segment new words, may largely benefit of the motivational and structuring properties of music in song.

Boundaries of separability between melody and rhythm in music discrimination: A neuropsychological perspective

The detailed study of a patient who suffered from a severe amelodia without arhythmia as a consequence of bilateral temporal lobe damage revealed that the processing of melodic information is at least partially separable from the processing of rhythmic information. This dissociation was replicated across different sets of material, was supported by the presence of a reversed association, and was maintained in conditions that promote integration in the normal brain. These results argue against the view that melody and rhythm are treated as a unified dimension throughout processing. At the same time, they support the view that integration takes place after early separation of the two dimensions.

Phonetic segmentation in prereaders: effect of corrective information

Abstract This study is focused on the capacity of preliterate children to learn explicit phonetic segmentation. In Experiment 1, subjects were induced through examples to delete the initial consonant in consonant-vowel-consonant (CVC) utterances. Performance was very poor at the beginning of the test but large improvements were observed in 5-year-olds when corrective feedback was provided. Four-year-olds did not on the average show a similar effect of feedback, but when tested again in Experiment 2 with a free segmentation procedure the majority proved capable of decomposing CVC syllables into smaller units and also displayed significant transfer from the earlier experience. In Experiment 3, fresh groups of children, aged four and five, were tested for either initial or final consonant deletion with immediate feedback. Improvements were observed at both ages and for both manipulations, although performance on initial consonant deletion was poorer than on final consonant deletion. Most children as young as 4 years can thus learn new segmentation games quite rapidly. The finding is discussed in relation to the notion that phonetic analysis is an important stumbling block in reading acquisition.

Attention-Dependent Changes of Activation and Connectivity in Dichotic Listening

Functional studies of auditory spatial attention generally report enhanced neural responses in auditory cortical regions. However, activity in regions of the spatial attentional network as described in the visual modality is not consistently observed. Data analysis limitations due to oppositely lateralized activity depending on the side of attentional orientation and heterogeneity of paradigms makes it hard to untangle the possible causes of these various activation patterns. In the present article we present a PET study of auditory spatial attention in which we manipulated orientation of attention, attentional load, and difficulty of the task by means of the dichotic listening paradigm. Moreover, we designed a systematic, voxel-specific, method in order to deal with oppositely lateralized activity. The results show that when listeners are involved in auditory spatial attention tasks an interacting network of frontal, temporal, and parietal regions is activated. Selective orientation toward one side mostly yields activity and connectivity modulations in the hemisphere contralateral to the attended side while in divided attention activity is mostly bilateral. Taken together, our observations are consistent with the idea of a multimodal large-scale attentional network.

The effects of literacy on the recognition of dichotic words

The hypothesis that awareness of phonemic segments influences the way in which speech is perceived was examined. Illiterate adults, who generally lack awareness of segments, were compared with literates, who are aware of the segmental structure of speech, on the recognition of words presented dichotically. A group of people who learned to read and write but who do it only occasionally was also tested. The results indicated much better performance in literates than in illiterates or semiliterates. In addition, literates made proportionally more single-segment errors, especially those limited to the first consonant, and fewer global errors, i.e. on all the segments of a syllable, than illiterates. On the other hand, phonetic feature blendings were as frequent in illiterates as in literates. It is suggested that awareness of segments allows attention to be focused on the phonemic constituents of speech and thus contributes to better recognition in difficult listening conditions. However, awareness of segments does not influence the preattentive extraction of phonetic information.

Awareness of Words as Phonological Entities: The Role of Literacy.

Illiterate, unschooled adults were tested on their notions of word length. Experiment 1 showed that only about half of them performed very poorly on a task requiring the production of a long/short word. They were clearly inferior to formerly illiterate, unschooled adults. The illiterate group also broke up neatly into two subgroups, one performing perfectly or very well, the other failing completely or almost completely, when required to match the written and the oral form of long/short words. Similarly, Experiment 2 showed that about half of the illiterates were unable to choose the longest of two names when presented with drawings of objects. The results suggest that learning to read, though not strictly necessary, plays a decisive role in the development of the ability of many individuals to focus on phonological length.

Is there a critical period for the acquisition of segmental analysis

Abstract Twelve Portuguese illiterate adults were required to delete the initial consonant of a spoken pseudoword and were provided with both explicit instructions and continuous corrective feedback. Nine of them displayed rapid improvements in performance. This suggests that there is no critical period for acquiring the ability of segmental analysis of speech.

Enantiomorphy through the looking glass: literacy effects on mirror-image discrimination.

To examine whether enantiomorphy (i.e., the ability to discriminate lateral mirror images) is influenced by the acquisition of a written system that incorporates mirrored letters (e.g., b and d), unschooled illiterate adults were compared with people reading the Latin alphabet, namely, both schooled literate adults and unschooled adults alphabetized in adulthood. In various sorting and same-different comparison tasks with nonlinguistic materials, illiterate participants displayed some sensitivity to enantiomorphic contrasts but performed far worse than all the other participant groups when the task required paying attention to such contrasts. The difficulties of illiterate participants were more severe with enantiomorphs than with rotations in the plane or shape contrasts. Learning a written system that incorporates enantiomorphic letters thus pushes the beginning reader to break the mirror invariance characteristic of the visual system, and this process generalizes beyond the realm of symbolic characters.