Jose Morais

Does awareness of speech as a sequence of phones arise spontaneously

It was found that illiterate adults could neither delete nor add a phone at the beginning of a non-word; but these tasks were rather easily performed by people with similar environment and childhood experiences, who learned to read rudimentarily as adults. Awareness of speech as a sequence of phones is thus not attained spontaneously in the course of general cognitive growth, but demands some specific training, which, for most persons, is probably provided by learning to read in the alphabetic system.

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.

Literacy training and speech segmentation

Abstract New groups of illiterate and ex-illiterate adults, comparable to those of Morais et. al (1979), were given a battery of tasks designed to assess the specificity of the effect of literacy training on speech segmentation. As in the previous study, a strong difference was observed between the two groups on the task of deleting the initial consonant of an utterance. The illeterates displayed the same incapacity to deal with phonetic segments in a detection task and in a progressive free segmentation task. Their performance was better, although still inferior to that of ex-illiterates, on both deletion and detection when the critical unit was a syllable rather than a consonant, as well as in a task of rhyme detection. No significant difference was observed in a task of melody segmentation, on which both groups performed poorly. The high specificity of the differences in performance level implies that they cannot result to an important extent from differences in general ability or motivation between the two groups of subjects. They rather mean that while sensitivity to rhyme and analysis into syllables can develop up to some point in the absence of the experience normally provided by reading instruction, analysis into phonetic segments requires that experience. Finally, in a picture memory task, the illiterates showed a phonological similarity effect, which is consistent with other results suggesting that the use of phonological codes for short-term retention does not require explicit phonetic analysis.

Phonetic analysis of speech and memory codes in beginning readers

Two experimental tasks, a speech segmentation and a short-term memory task, were presented to children who began to learn to read following either the “phonic” or the “wholeword” method. The segmentation task required the child to reverse two segments (either two phones or two syllables) in an utterance. The phonic group performed significantly better than the whole-word group in the “phonic reversal” task, but no difference appeared in the “syllable reversal” task. This indicated (1) that most children by the age of 6 years are ready to discover that speech consists of a sequence of phones and (2) that the moment at which they do it is influenced by the way they are taught to read. In the memory task, the children recalled series of visually presented items whose names either rhymed or did not. The difference in performance for the rhyming and nonrhyming series was significant in both groups. It was no greater for the phonic than for the whole-word group and was uncorrelated with the “phonic reversal” task. These results are discussed in connection with the distinction between ways of lexical access and ways of representing verbal information in short-term memory.

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.

Phonological Priming Between Monosyllabic Spoken Words

Phonological priming between 3-phoneme monosyllabic spoken words was examined as a function of the early or late position of the phonological overlap between the words and of prime-target relative frequency. The pairs of words had either the 2 beginning or the 2 final phonemes in common. Four experiments were conducted, each using a different combination of interstimulus interval (ISI; either 20 ms or 500 ms) and task (either lexical decision or shadowing). Facilitation was consistently found between words with final overlap in both tasks and was not affected by either absolute or relative word frequency. The size of the effect decreased as the ISI increased. Significant priming effects were not obtained between words with initial overlap, although an inhibitory trend was found in the shadowing task at the short ISI for the low-high relative frequency condition. It is suggested that the facilitatory effect of final overlap is prelexical.

Dichotic perception and laterality in neonates

Groups of 4-day-old neonates were tested for dichotic discrimination and ear differences with the High-Amplitude-Sucking procedure. In the first experiment, dichotic speech discrimination was attested by comparison with a control group. Furthermore, among those subjects who showed a substantial recovery of sucking response at least after one of the two syllable changes, it was observed that significantly more subjects manifested a stronger reaction to a right-ear change than to a left-ear change. In the second experiment, 4-day-old neonates were tested on syllable and music timbre discrimination. The significant Stimulus Type x Ear interaction observed suggests perceptual asymmetries indicative of very precocious brain specialization.

The locus of the orthographic consistency effect in auditory word recognition

In Experiments 1–2, we replicated with two different Portuguese materials the consistency effect observed for French by Ziegler and Ferrand (1998). Words with rimes that can be spelled in two different ways (inconsistent) produced longer auditory lexical decision latencies and more errors than did consistent words. In Experiment 3, which used shadowing, no effect of orthographic consistency was found. This task difference could reflect the confinement of orthographic influences to either decisional or lexical processes. In Experiment 4, we tried to untangle these two interpretations by comparing two situations in which a shadowing response was made contingent upon either a lexical or a phonemic criterion. A significant effect of orthographic consistency was observed only in lexically contingent shadowing. We thus argue that lexical but not sublexical processes are affected by orthographic consistency.

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.

SEGMENTATION ABILITIES OF DYSLEXICS AND NORMAL READERS

Dyslexia (15 boys, 12 girls, 6 to 9 yr.) were not poorer than normal readers (13 boys, 11 girls, 6 to 9 yr.) in segmenting tone sequences but much poorer in segmenting speech.