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How AI-supported intelligent systems support infection prevention and control training in healthcare: A systematic review of educational functions and outcomes.

AIMS: Artificial intelligence (AI)-supported intelligent systems have been increasingly incorporated into infection prevention and control (IPC) education and training, primarily to support the monitoring of observable behaviors and the provision of feedback. However, existing evidence has focused largely on short-term compliance outcomes, with limited synthesis of the educational role of AI-supported intelligent systems in supporting sustained IPC competence. This systematic review examined how AI-supported intelligent systems have been designed and used to support IPC education and training, with a focus on system characteristics, educational functions, and reported outcomes. DESIGN: A systematic literature search was conducted across the PubMed/MEDLINE, Embase, Cochrane, and CINAHL databases. DATA SOURCES: A total of 18 studies met the inclusion criteria. Findings were qualitatively synthesized according to system design characteristics, educational functions, and outcome domains. REVIEW METHODS: Methodological quality was appraised using the Mixed Methods Appraisal Tool. RESULTS: Most AI-supported intelligent systems focused on hand hygiene and relied on fully automated monitoring systems to capture behaviors and provide performance feedback. Educational functions were predominantly limited to performance assessment, automated feedback, and reminders. Outcomes were mainly measured using compliance or performance metrics, whereas sustained behavioral change and decision quality were rarely assessed. CONCLUSIONS: AI-supported intelligent systems have been used primarily to reinforce short-term IPC performance and compliance. However, their current applications for supporting sustained competence over time remain limited. The findings of this review suggest that AI-supported intelligent systems may serve as maintenance-oriented educational support by extending learning beyond initial instruction through repeated practice and feedback. Future research should prioritize outcome measures that capture the durability of performance and decision-making processes to better align AI-supported intelligent systems used in IPC education and training with the educational demands of clinical practice.

Humans↗

Relation between fluid intelligence and frontal lobe functioning in older adults.

This study reports the relations among normal aging, intelligence, and frontal lobe functioning. Intelligence tasks and frontal lobe functioning tasks were administered to 107 adults from two age groups (25 to 46 years and 70 to 99 years). Intelligence measures were assessed with two crystallized tests (WAIS Vocabulary and Information subtests), one fluid intelligence test (Cattell's Matrices), and one mixed, crystallized and fluid test (WAIS Similarities subtest). Frontal functioning was assessed using the Wisconsin Card Sorting Test (WCST) and two tests of verbal fluency. Significant age differences in favor of the young were found on the two intelligence tests with a fluid component and on all measures of frontal lobe functioning. Correlational analyses examining the relationship of intelligence measures to frontal variables indicated that these last measures were significantly correlated with only fluid intelligence tests in the elderly group. The implications for the relations among aging, fluid intelligence, and frontal lobe functioning are discussed.

Adult↗

Breast feeding and children's intelligence.

Breast feeding was reported in 1992 by Lucas, et al. to provide advantages for the development of intelligence in children of low birth weight, possibly through nutrients or other biological factors found in human breast milk but not cow's milk. Research on breast feeding and intelligence in children of normal birth weight has yielded mixed results, probably because measurement of environmental influences has not been thorough and the range of intelligence components measured has been limited. Our research with 204 3-year-old children of normal birth weight included control measures for the environment and maternal intelligence (Hollings-head socioeconomic status, Home Observation for the Measured Environment, Shipley) and two measures of childhood intelligence (Stanford-Binet Fourth Edition and Peabody Picture Vocabulary Test-Revised). Controlling for environmental variables and maternal intelligence, initiation of breast feeding predicted scores on intelligence tests at age three. Breast feeding was associated with 4.6-point higher mean in children's intelligence.

Breast Feeding↗

[Biological versus artificial intelligence: a critical approach].

After brief considerations about intelligence, a comparative study between biologic and artificial intelligence is made. The specialists in Artificial Intelligence found that intelligence is purely a matter of physical symbol manipulation. The enterprise of Artificial Intelligence aims to understand what we might call Brain Intelligence in terms of concepts and techniques of engineering. However the philosophers believed that computer-machine can have syntax, but can never have semantics. In other words, that they can follow rules, such as those of arithmetic or grammar, but not understand what to us are meanings of symbols, such as words. In the present paper it is stressed that brain/mind complex constitutes a monolithic systemic that functions with emergent properties at several levels of hierarchical organization. These hierarchical levels are non-reducible to one another. They are at least three (neuronal, functional, and semantic), and they function within an interactional plan. The brain/mind complex, which transform informations in meanings, deals with problems by means of both logical and non-logical mechanisms; while logic allows the mind to arrange the elements for reasoning, the non-logical mechanisms (fuzzy logic, heuristics, insights) allows the mind to develop strategies to find solutions. The model for construction of the "intelligent machine" is the operating way of the brain/mind complex, which does not always use logical processes. The role of information science in Artificial Intelligence is to search for knowledge itself (virtual knowledge), rather than to simply attempt a logico-mathematical formalization of knowledge.

Artificial Intelligence↗

Speech perception skills and speech production intelligibility in French children with prelingual deafness and cochlear implants.

OBJECTIVE: To examine speech perception and production intelligibility in French children with prelingual deafness who received multichannel cochlear implants. DESIGN: Within-subject, repeated-measures design for assessing speech perception and a cross-sectional design for assessing overall speech intelligibility. SETTING: A pediatric cochlear implant center. SUBJECTS: Sixty-four French children with prelingual deafness who received multichannel cochlear implants (mean age at time of implantation, 3 years 11 months) underwent assessment for speech perception. A subset of 16 children who received implants by 3 years of age underwent assessment for speech intelligibility. MAIN OUTCOME MEASURES: Speech perception skills were assessed using phoneme detection, closed-set word and sentence recognition, and modified open-set (MOS) recognition. Speech intelligibility was assessed by asking 50 listeners to identify recorded speech samples from the subjects. Dependent variables for the studies consisted of percent of correct items. RESULTS: After implantation, all children were able to detect phonemes by 3 months. Closed-set word and sentence identification reached 100% accuracy by 48 months (7 children with 4 years of implantation experience). Some children (8 of 48) demonstrated some MOS recognition after 1 year. Modified open-set recognition averaged 67.9% by 42 months (12 children available) and 80% by 48 months (7 children available). Overall speech intelligibility was 4.2% after 1 year, 30.7% after 2 years, 55.2% after 3 years, and 74.2% after 4 years. Within-subject comparison of MOS recognition and overall speech intelligibility scores revealed an insignificant trend for high perceptual performance to be associated with higher speech intelligibility scores (P = .17). There also was a tendency for higher performance to be associated with longer implantation experience. CONCLUSIONS: Speech perception scores appear to increase with increased experience using a cochlear implant. Overall speech intelligibility appears to steadily improve with increased experience and appears to be poorly related to perceptual performance on MOS recognition tasks.

Child, Preschool↗

Social complexity and social intelligence.

When we talk of the 'nature of intelligence', or any other attribute, we may be referring to its essential structure, or to its place in nature, particularly the function it has evolved to serve. Here I examine both, from the perspective of the evolution of intelligence in primates. Over the last 20 years, the Social (or 'Machiavellian') Intelligence Hypothesis has gained empirical support. Its core claim is that the intelligence of primates is primarily an adaptation to the special complexities of primate social life. In addition to this hypothesis about the function of intellect, a secondary claim is that the very structure of intelligence has been moulded to be 'social' in character, an idea that presents a challenge to orthodox views of intelligence as a general-purpose capacity. I shall outline the principal components of social intelligence and the environment of social complexity it engages with. This raises the question of whether domain specificity is an appropriate characterization of social intelligence and its subcomponents, like theory of mind. As a counter-argument to such specificity I consider the hypothesis that great apes exhibit a cluster of advanced cognitive abilities that rest on a shared capacity for second-order mental representation.

Animals↗

A comparative study of ERP correlates of psychometric and Piagetian intelligence measures in normal and hyperactive children.

Verbal and performance scores of the Wechsler Intelligence Scale for Children-Revised (WISC-R 1981) and of a Piagetian battery, the Cognitive Development Scale for Children (EDC 1984), were obtained on 30 normal control and 19 hyperactive 6-8-year-old children. Amplitudes and latencies of a fronto-central P250 and of the parieto-occipital N250, P350 and P500 were measured concurrently in 4 categorization tasks derived from tests of the WISC-R and EDC batteries. Spearman correlations were computed between the intelligence and the ERP factor scores. Results showed that age-related and age-corrected Wechsler's scores were correlated with similar ERP changes (reduced amplitude, decreased latency). With regard to the amplitude changes, each type of intelligence was associated with a specific ERP pattern. The verbal scores were correlated with the P350 and the P500 amplitudes, and the performance scores with the frontal P250 and occipital N250 amplitudes. By contrast, Piagetian development and intelligence scores yielded ERP correlates in the opposite direction: P500 amplitude was negatively correlated with raw EDC scores, but positively with scaled EDC scores. In addition, Piagetian intelligence was not related to the general peak latency decrease with age. In hyperactive children, additional negative correlations were found between P250 amplitude and the subjects' verbal test scores. Correlations with some performance tests that were negative in normal controls, were positive in hyperactive children. In addition, latency-based correlations found in normal controls were lacking in hyperactive children. These findings provide strong evidence that intelligence comprises different components related to different subsets of cognitive processes, as indexed by different ERP waves. They also suggest that the development and intelligence do not always rely on the same changes, and that intelligence forms may not be referred to the same use of the same processes in hyperactive and normal children.

Attention Deficit Disorder with Hyperactivity↗

Pregnancy outcome and intelligence at age five years.

OBJECTIVE: Our purpose was to determine the influence of being small for gestational age at term and being preterm < 34 weeks on cognitive functioning at age 5 years. STUDY DESIGN: Five hundred forty-six children of black low-income mothers, nearly all at risk for being small for gestational age, followed up prenatally with early ultrasonographic gestational age dating, were classified as either term appropriate for gestational age, term small for gestational age, or preterm at < 34 weeks. At a mean of 5.5 +/- 0.5 years, a Wechsler Preschool and Primary Scale of Intelligence-Revised intelligence quotient test was administered. An intelligence quotient < 70 was used to define mental retardation. Univariate and multivariate analyses adjusted for maternal age, smoking, education and language skills, home environment, and child gender and preschool attendance were performed. RESULTS: Term small-for-gestational-age and preterm infants at < 34 weeks had 4 and 6 point intelligence quotient reductions compared with term appropriate-for-gestational-age infants. In the regression analyses these differences in intelligence quotient remained significant after confounders were adjusted. High maternal receptive language level (8 points), a positive home environment (5 points), and attendance at preschool (5 points) were each significantly associated with an increase in intelligence quotient. CONCLUSION: Both term small-for-gestational-age infants and those born at < 34 weeks had a significantly lower mean intelligence quotient, and small-for-gestational-age infants had an increased risk of mental retardation at age 5 years. Higher maternal language skills, a positive home environment, and attendance at preschool each were associated with an increase in the mean intelligence quotient of 5 to 7 points.

Adult↗

Alcohol, intelligence and violent crime in young males.

Research has demonstrated a relationship between alcohol and violent behavior, but proof of a causal connection remains elusive. A recent review concluded that the key task that remained was to identify sub-groups of the population for which alcohol promotes violence. Because alcohol might induce violence by causing cognitive disruption (e.g., misunderstood communication), less intelligent persons could be vulnerable because they start out closer to the lower limit of comprehension. Our objective is to investigate the effect of lower intelligence on the alcohol/violence relationship. This analysis uses data from the Buffalo Longitudinal Study of Young Men to investigate this hypothesis. Males, 16 to 19 years of age (N = 596), were selected from Buffalo, NY, by random digit dialing. High-risk males were oversampled. Two interviews were conducted 18 months apart, including drinking, criminal offenses, and psychological traits. Verbal intelligence was measured by the Ammons Quick Test and visual-motor intelligence by the Trail Making Test. An analysis of covariance was conducted with wave 2 average alcohol consumption and both measures of intelligence as independent variables, violent offending as the dependent variable, and race, wave 1 alcohol and wave 1 violence as covariates. Results show a positive main effect of wave 2 alcohol consumption, but also interactions with both verbal and visual-motor intelligence. These interactions indicate that the prevalence of violence increases significantly at low intelligence and high alcohol consumption levels. A parallel analysis with nonviolent offending as the dependent variable failed to find significant interactions. The combination of heavy drinking and lower intelligence is associated with a synergistic surge of violent behavior.

Adolescent↗

Some relationships between intelligence and auditory discrimination.

Some of the earliest scientific attempts to understand the nature of intelligence investigated differences in sensory discrimination and reaction time. There is once again interest in the relations between such simple abilities and intelligence, partly as a result of the application of information-processing paradigms to the study of intelligence. Correlations in the range of .3 to .8 have been reported between psychometric measures of intelligence and performance on simple cognitive, sensory, and motor tasks. The current study reports correlations between scores on a battery of auditory discrimination tasks and measures of intelligence and academic aptitude in two samples of college students. The correlations between the intellectual and academic aptitude measures and the total percent correct on the auditory battery ranged from 45 to 59. These results are consistent with recent findings of significant relationships between simple sensory, cognitive, and motor abilities and psychometric intelligence as well as with much earlier reports by Spearman (1904) and others of relationships between pitch discrimination and intelligence. An implication of these findings is that intelligence is a potential confounding variable in studies of the auditory perceptual abilities of various clinical populations.

Auditory Perception↗

Speech intelligibility of children with cochlear implants, tactile aids, or hearing aids.

Speech intelligibility was measured in 31 children who used the 3M/House single-channel implant (n = 12), the Nucleus 22-Channel Cochlear Implant System (n = 15), or the Tactaid II + two-channel vibrotactile aid (n = 4). The subjects were divided into subgroups based on age at onset of deafness (early or late). The speech intelligibility of the experimental subjects was compared to that of children who were profoundly hearing impaired who used conventional hearing aids (n = 12) or no sensory aid (n = 2). The subjects with early onset of deafness who received their single- or multichannel cochlear implant before age 10 demonstrated the highest speech intelligibility, whereas subjects who did not receive their device until after age 10 had the poorest speech intelligibility. There was no obvious difference in the speech intelligibility scores of these subjects as a function of type of device (implant or tactile aid). On the average, the postimplant or tactile aid speech intelligibility of the subjects with early onset of deafness was similar to that of hearing aid users with hearing levels between 100 and 110 dB HL and limited hearing in the high frequencies. The speech intelligibility of subjects with late onset of deafness showed marked deterioration after the onset of deafness with relatively large improvements by most subjects after they received a single- or multichannel implant. The one subject with late onset of deafness who used a tactile aid showed no improvement in speech intelligibility.

Age Factors↗

Quantifying the relation between speech quality and speech intelligibility.

The purpose of the present research was to examine the relation between speech quality and speech intelligibility. Speech quality measurements were made using continuous discourse and a category rating procedure for the following dimensions: intelligibility, pleasantness, loudness, effort, and total impression. Measurements were made using a group of listeners with normal hearing for a set of stimulus conditions in which intelligibility varied, and for a set of stimulus conditions in which intelligibility was held constant near 100%. When ratings were made for a set of stimulus conditions in which intelligibility was allowed to vary (a) intersubject reliability was high (i.e., different listeners interpreted the dimensions in a similar manner); and (b) the speech quality dimensions of intelligibility, effort, and loudness were indistinguishable. When ratings were made for a set of stimulus conditions in which intelligibility was held constant (a) intersubject reliability was reduced, indicating that different listeners interpreted the dimensions in different ways; (b) most listeners rated each dimension differently, indicating that the dimensions were unique; and (c) across listeners, no single dimension was highly correlated with total impression. These results can be used in order to examine the relation between speech quality and speech intelligibility.

Adult↗

Vitamin-mineral intake and intelligence: a macrolevel analysis of randomized controlled trials.

CONTEXT: Two independent groups suspected that poor diets in school children might impair intelligence. Because dietary changes produce psychological effects, both groups conducted randomized trials in which children were challenged with placebo or vitamin-mineral tablets. Both reported significantly greater gains in intelligence among the actives. The findings were important because of the apparent inadequacy of diet they revealed, and the magnitude of the potential for increased intelligence. However, 5 of 11 replications were not significant, leaving the issue in doubt. OBJECTIVE: To determine if school children who receive low-dose vitamin-mineral tablets produce significantly higher IQ scores than children who receive placebo. DESIGN: A macrolevel analysis of the 13 known randomized, double-blind trials was undertaken. SETTING AND SUBJECTS: A total of 15 public schools in Arizona, California, Missouri, Oklahoma, Belgium, England, Scotland, and Wales participated, with 1477 school children, aged 6 to 17 years, and 276 young adult males, aged 18 to 25 years, in 2 American correctional facilities. MAIN OUTCOME MEASURES: All studies used 1 of 3 standardized tests of nonverbal intelligence: the Wechsler Intelligence Scale for Children-Revised, the Wechsler Adult Intelligence Scale, or the Calvert Non-verbal test. RESULTS: The activities in each study performed better, on average, than placebo in nonverbal IQ, regardless of formula, location, age, race, gender, or research team composition. The probability of 13 randomly selected experimental groups always performing better than 13 randomly selected independent control groups is one-half to the 13th power (p = 0.000122). The mean difference across all studies is 3.2 IQ points. Furthermore, the standard deviation in the variable "IQ change" was also consistently larger in each active group when compared to its controls. This confirms that a few children in each study, presumably the poorly nourished minority, were producing large differences, rather than a 3.2 point gain in all active children. CONCLUSION: There are important health risks when school children's dietary habits depart substantially from government guidelines; poor dietary habits may lead to impaired intelligence. Low-dose vitamin-mineral supplementation may restore the cognitive abilities of these children by raising low blood nutrient concentrations. However, there is also evidence that supplementation has no measurable effect on the intelligence of well-nourished children with normal blood nutrient concentrations.

Adolescent↗

The effect of vitamin-mineral supplementation on the intelligence of American schoolchildren: a randomized, double-blind placebo-controlled trial.

CONTEXT: Many medical, nutrition, and education professionals have long suspected that poor diet impairs the academic performance of Western schoolchildren; academic performance often improves after improved diet. However, others have suggested that such academic gains may be due to psychologic effects rather than nutrition. To resolve this issue, two independent research teams conducted randomized trials in which children were given placebos or low-dose vitamin-mineral tablets designed to raise nutrient intake to the equivalent of a well-balanced diet. Both teams reported significantly greater gains in nonverbal intelligence among the supplemented groups. The findings were important because of the apparent inadequacy of diet they revealed and the magnitude of the potential for increased intelligence. However, none of the ten subsequent replications, or the two original trials, were without limitations leaving this issue in controversy. OBJECTIVES: To determine if schoolchildren who consume low-dose vitamin-mineral tablets will have a significantly larger increase in nonverbal intelligence than children who consume placebos in a study that overcomes the primary criticisms directed at the previous 12 controlled trials. DESIGN: A double-blind, placebo-controlled trial using stratified randomization within each teacher's class based on preintervention nonverbal intelligence. SETTINGS AND SUBJECTS: Two "working class," primarily Hispanic, elementary schools in Phoenix, Arizona, participated in the study. Slightly more than half the teachers in each school distributed the tablets daily to 245 schoolchildren aged 6 to 12 years. INTERVENTION: Daily vitamin-mineral supplementation at 50% of the U.S. daily recommended allowance (RDA) for 3 months versus placebo. OUTCOME MEASURES: Post-test nonverbal IQ, as measured by the Wechsler Intelligence Scale for Children-Revised (WISC-R), while controlling for pretest nonverbal IQ as a covariate. FOUR MAIN RESULTS: First, a significant difference of 2.5 IQ points (95% CI: 1.85-3.15) was found between 125 children given active tablets and 120 children given placebo tablets (p = 0.038). Second, this finding is consistent with the mean 3.2 IQ point net gain found in the 12 similar but less rigorous studies. Third, a significantly higher proportion of children in the active group gained 15 or more IQ points when compared to the placebo group (p < 0.01). Fourth, although 81 matched pairs produced no difference at all in nonverbal IQ gain, the modest 2.5 IQ point net gain for the entire sample can be explained by the remaining 24 children who took active tablets, and had a 16 point higher net gain in IQ than the remaining 19 placebo controls. CONCLUSIONS: This study confirms that vitamin-mineral supplementation modestly raised the nonverbal intelligence of some groups of Western schoolchildren by 2 to 3 points but not that of most Western schoolchildren, presumably because the majority were already adequately nourished. This study also confirms that vitamin-mineral supplementation markedly raises the non-verbal intelligence of a minority of Western schoolchildren, presumably because they were too poorly nourished before supplementation for optimal brain function. Because nonverbal intelligence is closely associated with academic performance, it follows that schools with children who consume substandard diets should find it difficult to produce academic performance equal to those schools with children who consume diets that come closer to providing the nutrients suggested in the U.S. RDA. The parents of schoolchildren whose academic performance is substandard would be well advised to seek a nutritionally oriented physician for assessment of their children's nutritional status as a possible etiology.

Arizona↗

Reliability of audiologists' ratings of the intelligibility of hearing-impaired children's speech.

The reliability of intelligibility judgments of hearing-impaired children's speech was investigated. Twenty Australian audiologists, untrained in the use of speech intelligibility scales, rated the speech intelligibility of 20 hearing-impaired children, using the National Technical Institute for the Deaf speech intelligibility scale on one occasion and a percentage intelligible scale on another. Inter-rater reliability was high for both scales (Kendall's W greater than 0.80, p less than 0.001), as was intra-rater reliability (r greater than 0.90, p less than 0.001; rcc greater than 0.88). Training in the use of speech intelligibility rating procedures does not appear necessary for reliable judgments. However, the perceived intelligibility of some children's speech was highly listener dependent regardless of the scale used, indicating that a variance measure should be reported in addition to means in descriptions of perceived intelligibility.

Adolescent↗

Comparing the effects of alcohol and intelligence on text recall and recognition.

Forty male subjects were divided into two groups on the basis of their scores on a computerized intelligence test administered in a preliminary session. They then participated in a text recall and recognition experiment in which they received alcohol (1.0 ml/kg body weight) in one session and no alcohol in another session (the order being counterbalanced). Subjects were required to read a short passage, immediately recall as much of it as possible and then select from sets of four sentences the ones that appeared in the original passage (recognition). Although two different passages were used, and subjects knew about the memory tasks in advance, there was nevertheless a significant practice effect: subjects recalled 10.6 per cent more propositions on the second occasion than on the first, but this could be at least partly explained by the fact that they spent 10.0 per cent longer reading the second passage. There was also a significant 7.8 per cent slowing of reading time due to alcohol. Practice did not interact with either intelligence or alcohol on any measure of performance. Alcohol impaired the performance of high intelligence test scorers more than low scorers. The effects of intelligence and alcohol on free recall were quantitatively similar: high intelligence test scorers recalled 8.7 more propositions than low scorers; with alcohol, subjects recalled 8.3 fewer propositions than without alcohol. However, the effects were qualitatively different. The effect of intelligence was primarily on the recall of lower level propositions, whereas alcohol impaired the recall of both higher and lower level propositions. Furthermore, while there was no effect of intelligence on recognition, alcohol impaired performance such that more incorrect sentences were erroneously recognized, particularly those which altered the meaning of the original sentence, rather than merely its surface structure. In terms of Kintsch & van Dijk's (1978) model of text processing, the results are interpreted as suggesting that, while both intelligence and alcohol affect the capacity of the short-term memory buffer, there is an additional impairment with alcohol in the ability to select between higher and lower level propositions prior to filling the buffer.

Adolescent↗

The effect of timing errors on the intelligibility of deaf children's speech.

The purpose of this study was to quantify the effect of timing errors on the intelligibility of deaf children's speech. Deviant timing patterns were corrected in the recorded speech samples of six deaf children using digital speech processing techniques. The speech waveform was modified to correct timing errors only, leaving all other aspects of the speech unchanged. The following six-stage approximation procedure was used to correct the deviant timing patterns: (1) original, unaltered utterances, (2) correction of pauses only, (3) correction of relative timing, (4) correction of absolute syllable duration, (5) correction of relative timing and pauses, and (6) correction of absolute syllable duration and pauses. Measures of speech intelligibility were obtained for the original and the computer-modified utterances. On the average, the highest intelligibility score was obtained when relative timing errors only were corrected. The correction of this type of error improved the intelligibility of both stressed and unstressed words within a phrase. Improvements in word intelligibility, which occurred when relative timing was corrected, appeared to be closely related to the number of phonemic errors present within a word. The second highest intelligibility score was obtained for the original, unaltered sentences. On the average, the intelligibility scores obtained for the other four forms of timing modification were poorer than those obtained for the original sentences. Thus, the data show that intelligibility improved, on the average, when only one type of error, relative timing, was corrected.

Adolescent↗

Intelligibility of vowels produced by post-lingually deafened cochlear implant users.

The present study addresses the effect of cochlear implantation on the intelligibility of vowels produced by 20 post-lingually deafened Dutch subjects. All subjects received the Nucleus-22 cochlear implant (3 WSP and 17 MSP processors). Speech recordings were made pre-implantation and three and twelve months post-implantation with the implant switched on and off. Vowel intelligibility (monophthongs only) was determined using a panel of listeners. For all implanted subjects intelligibility was measured in a noisy background. For seven poorly speaking subjects it was also measured in a quiet background. After implantation with the Nucleus-22 device the results showed that vowel intelligibility, measured for all subjects in a noisy background, increased for most of them (about 15), while it increased for about half the number of poorly speaking subjects measured in a quiet background. Twelve months after implantation vowel intelligibility, measured for all subjects in noise, appeared to be based on first and second formant information. This was also found for the subgroup of seven subjects performing poorly pre-implantation when analysed separately. However, vowel intelligibility for this subgroup, when measured in a quiet background, was based also on vowel duration. The differences between the overall result in noise and the results of the subgroup in quiet should be attributed mainly to the noise and not to aspects of poor speech production in the subgroup. In addition, this study addresses the relationship between the intelligibility scores and objective measurements of vowel quality performed in a previous study. The results showed that the vowel intelligibility scores are mainly determined by the position of the second formant frequencies.

Adult↗