John S. Pruitt

Personas: practice and theory

ì Personasî is an interaction design technique with considerable potential for software product development. In three years of use, our colleagues and we have extended Alan Cooperís technique to make Personas a powerful complement to other usability methods. After describing and illustrating our approach, we outline the psychological theory that explains why Personas are more engaging than design based primarily on scenarios. As Cooper and others have observed, Personas can engage team members very effectively. They also provide a conduit for conveying a broad range of qualitative and quantitative data, and focus attention on aspects of design and use that other methods do not.

Neural Signatures of Phonetic Learning in Adulthood: A Magnetoencephalography Study

The present study used magnetoencephalography (MEG) to examine perceptual learning of American English /r/ and /l/ categories by Japanese adults who had limited English exposure. A training software program was developed based on the principles of infant phonetic learning, featuring systematic acoustic exaggeration, multi-talker variability, visible articulation, and adaptive listening. The program was designed to help Japanese listeners utilize an acoustic dimension relevant for phonemic categorization of /r-l/ in English. Although training did not produce native-like phonetic boundary along the /r-l/ synthetic continuum in the second language learners, success was seen in highly significant identification improvement over twelve training sessions and transfer of learning to novel stimuli. Consistent with behavioral results, pre-post MEG measures showed not only enhanced neural sensitivity to the /r-l/ distinction in the left-hemisphere mismatch field (MMF) response but also bilateral decreases in equivalent current dipole (ECD) cluster and duration measures for stimulus coding in the inferior parietal region. The learning-induced increases in neural sensitivity and efficiency were also found in distributed source analysis using Minimum Current Estimates (MCE). Furthermore, the pre-post changes exhibited significant brain-behavior correlations between speech discrimination scores and MMF amplitudes as well as between the behavioral scores and ECD measures of neural efficiency. Together, the data provide corroborating evidence that substantial neural plasticity for second-language learning in adulthood can be induced with adaptive and enriched linguistic exposure. Like the MMF, the ECD cluster and duration measures are sensitive neural markers of phonetic learning.

Effects of category knowledge and syllable truncation during auditory training on Americans' discrimination of Hindi retroflex‐dental contrasts

Previous research has shown that the Hindi retroflex‐dental contrast among stop consonants is not easily differentiated by English speakers even after some training. In the present study, subjects were given four days of training (768 trials) in a categorial AX discrimination task on full (unmodified) or truncated tokens of naturally produced breathy‐voiced [důha] vs [důha]. Truncation involved removing the vowel from the syllables. Half the subjects were given category knowledge during training (i.e., response forms listed the identity of the first token of each pair). Truncation of the stimuli resulted in better performance during training, but the advantage did not transfer to post tests with the full syllables. Category knowledge resulted in greater improvement during training on both truncated and full syllables. It also led to better performance on the post test of full syllables only for subjects trained on full syllables. Large individual differences found in each training condition suggest that s...

Putting personas to work

Personas for use in interaction and interface design have generated a great deal of interest, but the method is still relatively new. This panel brings together professionals who have used personas to solve real business problems. The panelists will describe the methods they have developed to put personas to work in their organizations and how the use of personas has impacted their products and their organizations.

Perceptual training on Hindi dental and retroflex consonants by native English and Japanese speakers

Previous research has shown that both native English and native Japanese speakers have great difficulty distinguishing the dental and retroflex stop‐consonants of the Hindi language. However, Japanese speakers perform much better than English speakers—particularly on voiced‐unaspirated consonants. This differential performance is thought to be due to contrastive experience that Japanese have with /d/ versus flapped /r/. (While English does contain a flapped /r/, it is not contrasted with /d/.) This research further compared English and Japanese speakers’ ability to distinguish the Hindi contrast by providing laboratory training and generalization tests for both language groups. Twenty native speakers from each language group were pretested and post‐tested on voiced‐aspirated, voiced‐unaspirated, voiceless‐aspirated, and voiceless‐unaspirated dental and retroflex consonant‐vowel syllables produced by 2 native Hindi speakers in 3 vowel contexts (/a/, /e/, /o/). Training consisted of 12, 30‐min sessions in w...

Brain plasticity in behavioral and neuromagnetic measures: A perceptual training study

The present study investigated brain plasticity in Japanese adults learning the English /l–r/ distinction. Both behavioral and brain (MEG) measures were used. Training was designed to mimic the listening experience of infants who are exposed to the exaggerated acoustic events contained in infant‐directed speech (‘‘motherese’’). A multimedia software program incorporated major features conducive to perceptual learning. The program consisted of 12 1‐h training sessions. Pre‐ and post‐training measures were collected from nine subjects including two controls. The MEG experiments examined training effects in preattentive discrimination versus categorization conditions. An average improvement of 21.7% was obtained behaviorally. The training effect was significant for all factors of speaker, vowel, and syllabic context. Perceptual learning generalized to three untrained voices. No effects were observed in the two control subjects. Consistent with the behavioral results, the MEG data showed significantly improve...

Perceptual identification training of American English /r/ and /l/ by Japanese speakers generalizes to novel stimuli and tasks

This study investigated the extent to which results from /r/ and /l/ perceptual identification training generalized to identification of novel natural stimuli and discrimination of synthetic stimuli in ten native Japanese speakers. A behavioral training software program was used which incorporated factors known to affect the acquisition of phonemic distinctions, including bimodal speech cues, stimulus variability, and subject‐controlled stimulus presentation with immediate feedback. Natural speech tokens were digitally manipulated to create three levels of acoustic exaggeration. These levels, and other stimulus characteristics such as the number of talkers, vowel contexts, and syllable structure, varied during each training session as a function of listener’s performance. Pre‐ and post‐training identification tasks measured generalization to natural tokens of novel talkers and vowel contexts. In addition, pre‐ and post‐training discrimination tasks measured generalization to novel tasks and synthetic stim...

Comments on ‘‘Training Japanese listeners to identify English /r/ and /l/: A first report’’ [J. S. Logan, S. E. Lively, and D. B. Pisoni, J. Acoust. Soc. Am. 89, 874–886 (1991)]

An attempt to improve our understanding of how laboratory training affects cross‐language speech perception was reported recently by Logan et al. [J. Acoust. Soc. Am. 89, 874–886 (1991)]. However, several problems in methodology have prompted a critique of their report. The following discussion explores these problems in an effort to clarify the issues and assess the claims of the authors.

Persona conception and gestation

This chapter discusses the persona conception and gestation. Conception and gestation is the phase of the persona lifecycle in which one actually creates their personas. It is the phase in which one use data to create engaging representations of individual users that their team can use for planning, design, and development. During this phase, one faces the tricky question of how many personas to create and how to prioritize them. One processes the data and assumptions one has collected (by prioritizing, filtering, and organizing) to discover information about your users. Using this information, one and their core team creates bulleted persona “skeletons” that key stakeholders can prioritize according to business goals. One develops their prioritized skeletons into complete personas that are then ready to be introduced to their organization in the birth and maturation phase Conception and gestation is the phase of the persona lifecycle in which one actually create their personas. It is the phase in which one use data to create engaging representations of individual users that their team can use for planning, design, and development.

Developmental changes in the discrimination of Hindi dental‐retroflex consonants by American–English children between childhood and puberty

There are many studies comparing adult and infant perception of non‐native speech sounds, with results typically showing that infants outperform adults on non‐native phonetic discrimination. However, there is a lack of research that investigates the developmental change in native and non‐native speech perception, particularly from early childhood to puberty, when plasticity for learning a new language appears to decline. In an attempt to better understand the effects of language experience on native and non‐native speech perception during this period, the current study examined 6 to 15‐year‐old American–English children’s ability to discriminate Hindi dental‐retroflex consonants. Discrimination data were obtained using four phonetically different consonant–vowel contrasts that are phonemic in Hindi but not in English. Discrimination data were also obtained using a native‐language contrast (AE /r/ vs /l/). For comparison, American–English and Hindi adults were tested. A newly developed computer‐based testi...