Iconicity ratings for 14,000+ English words

Iconic words and signs are characterized by a perceived resemblance between aspects of their form and aspects of their meaning. For example, in English, iconic words include peep and crash, which mimic the sounds they denote, and wiggle and zigzag, which mimic motion. As a semiotic property of words and signs, iconicity has been demonstrated to play a role in word learning, language processing, and language evolution. This paper presents the results of a large-scale norming study for more than 14,000 English words conducted with over 1400 American English speakers. We demonstrate the utility of these ratings by replicating a number of existing findings showing that iconicity ratings are related to age of acquisition, sensory modality, semantic neighborhood density, structural markedness, and playfulness. We discuss possible use cases and limitations of the rating dataset, which is made publicly available.

Great apes reach momentary altered mental states by spinning

Among animals, humans stand out in their consummate propensity to self-induce altered states of mind. Archaeology, history and ethnography show these activities have taken place since the beginnings of civilization, yet their role in the emergence and evolution of the human mind itself remains debatable. The means through which modern humans actively alter their experience of self and reality frequently depend on psychoactive substances, but it is uncertain whether psychedelics or other drugs were part of the ecology or culture of pre-human ancestors. Moreover, (nonhuman) great apes in captivity are currently being retired from medical research, rendering comparative approaches thus far impracticable. Here, we circumvent this limitation by harnessing the breadth of publicly available YouTube data to show that apes engage in rope spinning during solitary play. When spinning, the apes achieved speeds sufficient to alter self-perception and situational awareness that were comparable to those tapped for transcendent experiences in humans (e.g. Sufi whirling), and the number of revolutions spun predicted behavioural evidence for dizziness. Thus, spinning serves as a self-sufficient means of changing body-mind responsiveness in hominids. A proclivity for such experiences is shared between humans and great apes, and provides an entry point for the comparative study of the mechanisms, functions, and adaptive value of altered states of mind in human evolution.

Trilled /r/ is associated with roughness, linking sound and touch across spoken languages

Cross-modal integration between sound and texture is important to perception and action. Here we show this has repercussions for the structure of spoken languages. We present a new statistical universal linking speech with the evolutionarily ancient sense of touch. Words that express roughness—the primary perceptual dimension of texture—are highly likely to feature a trilled /r/, the most commonly occurring rhotic consonant. In four studies, we show the pattern to be extremely robust, being the first widespread pattern of iconicity documented not just across a large, diverse sample of the world’s spoken languages, but also across numerous sensory words within languages. Our deep analysis of Indo-European languages and Proto-Indo-European roots indicates remarkable historical stability of the pattern, which appears to date back at least 6000 years.

The bouba/kiki effect is robust across cultures and writing systems

The bouba/kiki effect-the association of the nonce word bouba with a round shape and kiki with a spiky shape-is a type of correspondence between speech sounds and visual properties with potentially deep implications for the evolution of spoken language. However, there is debate over the robustness of the effect across cultures and the influence of orthography. We report an online experiment that tested the bouba/kiki effect across speakers of 25 languages representing nine language families and 10 writing systems. Overall, we found strong evidence for the effect across languages, with bouba eliciting more congruent responses than kiki. Participants who spoke languages with Roman scripts were only marginally more likely to show the effect, and analysis of the orthographic shape of the words in different scripts showed that the effect was no stronger for scripts that use rounder forms for bouba and spikier forms for kiki. These results confirm that the bouba/kiki phenomenon is rooted in crossmodal correspondence between aspects of the voice and visual shape, largely independent of orthography. They provide the strongest demonstration to date that the bouba/kiki effect is robust across cultures and writing systems. This article is part of the theme issue 'Voice modulation: from origin and mechanism to social impact (Part II)'.

Voice modulation: from origin and mechanism to social impact

Research on within-individual modulation of vocal cues is surprisingly scarce outside of human speech. Yet, voice modulation serves diverse functions in human and nonhuman nonverbal communication, from dynamically signalling motivation and emotion, to exaggerating physical traits such as body size and masculinity, to enabling song and musicality. The diversity of anatomical, neural, cognitive and behavioural adaptations necessary for the production and perception of voice modulation make it a critical target for research on the origins and functions of acoustic communication. This diversity also implicates voice modulation in numerous disciplines and technological applications. In this two-part theme issue comprising 21 articles from leading and emerging international researchers, we highlight the multidisciplinary nature of the voice sciences. Every article addresses at least two, if not several, critical topics: (i) development and mechanisms driving vocal control and modulation; (ii) cultural and other environmental factors affecting voice modulation; (iii) evolutionary origins and adaptive functions of vocal control including cross-species comparisons; (iv) social functions and real-world consequences of voice modulation; and (v) state-of-the-art in multidisciplinary methodologies and technologies in voice modulation research. With this collection of works, we aim to facilitate cross-talk across disciplines to further stimulate the burgeoning field of voice modulation. This article is part of the theme issue 'Voice modulation: from origin and mechanism to social impact (Part I)'.

Vocal communication of magnitude across language, age, and auditory experience

Like many other vocalizing vertebrates, humans convey information about their body size through the sound of their voice. Vocalizations of larger animals are typically longer in duration, louder in intensity, and lower in frequency. We investigated people's ability to use voice-size correspondences to communicate about the magnitude of external referents. First, we asked hearing children, as well as deaf children and adolescents, living in China to improvise nonlinguistic vocalizations to distinguish between paired items contrasting in magnitude (e.g., a long vs. short string, a big vs. small ball). Then we played these vocalizations back to adult listeners in the United States and China to assess their ability to correctly guess the intended referents. We find that hearing and deaf producers both signaled greater magnitude items with longer and louder vocalizations and with smaller formant spacing. Only hearing producers systematically used fundamental frequency, communicating greater magnitude with higher fo. The vocalizations of both groups were understandable to Chinese and American listeners, although accuracy was higher with vocalizations from older producers. American listeners relied on the same acoustic properties as Chinese listeners: both groups interpreted vocalizations with longer duration and greater intensity as referring to greater items; neither American nor Chinese listeners consistently used fo or formant spacing as a cue. These findings show that the human ability to use vocalizations to communicate about the magnitude of external referents is highly robust, extending across listeners of disparate linguistic and cultural backgrounds, as well as across age and auditory experience. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Novel vocalizations are understood across cultures

Linguistic communication requires speakers to mutually agree on the meanings of words, but how does such a system first get off the ground? One solution is to rely on iconic gestures: visual signs whose form directly resembles or otherwise cues their meaning without any previously established correspondence. However, it is debated whether vocalizations could have played a similar role. We report the first extensive cross-cultural study investigating whether people from diverse linguistic backgrounds can understand novel vocalizations for a range of meanings. In two comprehension experiments, we tested whether vocalizations produced by English speakers could be understood by listeners from 28 languages from 12 language families. Listeners from each language were more accurate than chance at guessing the intended referent of the vocalizations for each of the meanings tested. Our findings challenge the often-cited idea that vocalizations have limited potential for iconic representation, demonstrating that in the absence of words people can use vocalizations to communicate a variety of meanings.

'Tiny numbers' are actually tiny: Evidence from gestures in the TV News Archive

We report a large-scale, quantitative investigation of manual gestures that speakers perform when speaking metaphorically about numerical quantities. We used the TV News Archive–an online database of over 2 million English language news broadcasts–to examine 681 videos in which 584 speakers used the phrase 'tiny number', 'small number', 'large number', or 'huge number', which metaphorically frame numerical quantity in terms of physical size. We found that the gestures speakers used reflect a number of different strategies to express the metaphoric size of quantities. When referring to greater versus lesser quantities, speakers were far more likely to gesture (1) with an open versus closed hand configuration, (2) with an outward versus inward movement, and (3) with a wider distance between the gesturing hands. These patterns were often more pronounced for the phrases containing more extreme adjectives ('tiny/huge number'). However, we did not find that speakers performed two-handed versus one-handed gestures. Nor did we find that speakers performed right-handed versus left-handed gestures, when referring to greater versus lesser quantities. Overall, this work supports the claim that metaphoric thought is involved in the production of verbal metaphors that describe numerical magnitudes. It demonstrates that size-based numerical associations observed in previous lab experiments are active in real-life communication outside the lab.

Repeated imitation makes human vocalizations more word-like

People have long pondered the evolution of language and the origin of words. Here, we investigate how conventional spoken words might emerge from imitations of environmental sounds. Does the repeated imitation of an environmental sound gradually give rise to more word-like forms? In what ways do these forms resemble the original sounds that motivated them (i.e. exhibit iconicity)? Participants played a version of the children's game 'Telephone'. The first generation of participants imitated recognizable environmental sounds (e.g. glass breaking, water splashing). Subsequent generations imitated the previous generation of imitations for a maximum of eight generations. The results showed that the imitations became more stable and word-like, and later imitations were easier to learn as category labels. At the same time, even after eight generations, both spoken imitations and their written transcriptions could be matched above chance to the category of environmental sound that motivated them. These results show how repeated imitation can create progressively more word-like forms while continuing to retain a resemblance to the original sound that motivated them, and speak to the possible role of human vocal imitation in explaining the origins of at least some spoken words.

Iconicity in Signed and Spoken Vocabulary: A Comparison Between American Sign Language, British Sign Language, English, and Spanish

Considerable evidence now shows that all languages, signed and spoken, exhibit a significant amount of iconicity. We examined how the visual-gestural modality of signed languages facilitates iconicity for different kinds of lexical meanings compared to the auditory-vocal modality of spoken languages. We used iconicity ratings of hundreds of signs and words to compare iconicity across the vocabularies of two signed languages - American Sign Language and British Sign Language, and two spoken languages - English and Spanish. We examined (1) the correlation in iconicity ratings between the languages; (2) the relationship between iconicity and an array of semantic variables (ratings of concreteness, sensory experience, imageability, perceptual strength of vision, audition, touch, smell and taste); (3) how iconicity varies between broad lexical classes (nouns, verbs, adjectives, grammatical words and adverbs); and (4) between more specific semantic categories (e.g., manual actions, clothes, colors). The results show several notable patterns that characterize how iconicity is spread across the four vocabularies. There were significant correlations in the iconicity ratings between the four languages, including English with ASL, BSL, and Spanish. The highest correlation was between ASL and BSL, suggesting iconicity may be more transparent in signs than words. In each language, iconicity was distributed according to the semantic variables in ways that reflect the semiotic affordances of the modality (e.g., more concrete meanings more iconic in signs, not words; more auditory meanings more iconic in words, not signs; more tactile meanings more iconic in both signs and words). Analysis of the 220 meanings with ratings in all four languages further showed characteristic patterns of iconicity across broad and specific semantic domains, including those that distinguished between signed and spoken languages (e.g., verbs more iconic in ASL, BSL, and English, but not Spanish; manual actions especially iconic in ASL and BSL; adjectives more iconic in English and Spanish; color words especially low in iconicity in ASL and BSL). These findings provide the first quantitative account of how iconicity is spread across the lexicons of signed languages in comparison to spoken languages.

People Can Create Iconic Vocalizations to Communicate Various Meanings to Naïve Listeners

The innovation of iconic gestures is essential to establishing the vocabularies of signed languages, but might iconicity also play a role in the origin of spoken words? Can people create novel vocalizations that are comprehensible to naïve listeners without prior convention? We launched a contest in which participants submitted non-linguistic vocalizations for 30 meanings spanning actions, humans, animals, inanimate objects, properties, quantifiers and demonstratives. The winner was determined by the ability of naïve listeners to infer the meanings of the vocalizations. We report a series of experiments and analyses that evaluated the vocalizations for: (1) comprehensibility to naïve listeners; (2) the degree to which they were iconic; (3) agreement between producers and listeners in iconicity; and (4) whether iconicity helps listeners learn the vocalizations as category labels. The results show contestants were able to create successful iconic vocalizations for most of the meanings, which were largely comprehensible to naïve listeners, and easier to learn as category labels. These findings demonstrate how iconic vocalizations can enable interlocutors to establish understanding in the absence of conventions. They suggest that, prior to the advent of full-blown spoken languages, people could have used iconic vocalizations to ground a spoken vocabulary with considerable semantic breadth.

Iconicity in the speech of children and adults

Iconicity - the correspondence between form and meaning - may help young children learn to use new words. Early-learned words are higher in iconicity than later learned words. However, it remains unclear what role iconicity may play in actual language use. Here, we ask whether iconicity relates not just to the age at which words are acquired, but also to how frequently children and adults use the words in their speech. If iconicity serves to bootstrap word learning, then we would expect that children should say highly iconic words more frequently than less iconic words, especially early in development. We would also expect adults to use iconic words more often when speaking to children than to other adults. We examined the relationship between frequency and iconicity for approximately 2000 English words. Replicating previous findings, we found that more iconic words are learned earlier. Moreover, we found that more iconic words tend to be used more by younger children, and adults use more iconic words when speaking to children than to other adults. Together, our results show that young children not only learn words rated high in iconicity earlier than words low in iconicity, but they also produce these words more frequently in conversation - a pattern that is reciprocated by adults when speaking with children. Thus, the earliest conversations of children are relatively higher in iconicity, suggesting that this iconicity scaffolds the production and comprehension of spoken language during early development.

Iconicity in English and Spanish and Its Relation to Lexical Category and Age of Acquisition

Signed languages exhibit iconicity (resemblance between form and meaning) across their vocabulary, and many non-Indo-European spoken languages feature sizable classes of iconic words known as ideophones. In comparison, Indo-European languages like English and Spanish are believed to be arbitrary outside of a small number of onomatopoeic words. In three experiments with English and two with Spanish, we asked native speakers to rate the iconicity of ~600 words from the English and Spanish MacArthur-Bates Communicative Developmental Inventories. We found that iconicity in the words of both languages varied in a theoretically meaningful way with lexical category. In both languages, adjectives were rated as more iconic than nouns and function words, and corresponding to typological differences between English and Spanish in verb semantics, English verbs were rated as relatively iconic compared to Spanish verbs. We also found that both languages exhibited a negative relationship between iconicity ratings and age of acquisition. Words learned earlier tended to be more iconic, suggesting that iconicity in early vocabulary may aid word learning. Altogether these findings show that iconicity is a graded quality that pervades vocabularies of even the most “arbitrary” spoken languages. The findings provide compelling evidence that iconicity is an important property of all languages, signed and spoken, including Indo-European languages.

Iconicity can ground the creation of vocal symbols

Studies of gestural communication systems find that they originate from spontaneously created iconic gestures. Yet, we know little about how people create vocal communication systems, and many have suggested that vocalizations do not afford iconicity beyond trivial instances of onomatopoeia. It is unknown whether people can generate vocal communication systems through a process of iconic creation similar to gestural systems. Here, we examine the creation and development of a rudimentary vocal symbol system in a laboratory setting. Pairs of participants generated novel vocalizations for 18 different meanings in an iterative 'vocal' charades communication game. The communicators quickly converged on stable vocalizations, and naive listeners could correctly infer their meanings in subsequent playback experiments. People's ability to guess the meanings of these novel vocalizations was predicted by how close the vocalization was to an iconic 'meaning template' we derived from the production data. These results strongly suggest that the meaningfulness of these vocalizations derived from iconicity. Our findings illuminate a mechanism by which iconicity can ground the creation of vocal symbols, analogous to the function of iconicity in gestural communication systems.

Learned vocal and breathing behavior in an enculturated gorilla

We describe the repertoire of learned vocal and breathing-related behaviors (VBBs) performed by the enculturated gorilla Koko. We examined a large video corpus of Koko and observed 439 VBBs spread across 161 bouts. Our analysis shows that Koko exercises voluntary control over the performance of nine distinctive VBBs, which involve variable coordination of her breathing, larynx, and supralaryngeal articulators like the tongue and lips. Each of these behaviors is performed in the context of particular manual action routines and gestures. Based on these and other findings, we suggest that vocal learning and the ability to exercise volitional control over vocalization, particularly in a multimodal context, might have figured relatively early into the evolution of language, with some rudimentary capacity in place at the time of our last common ancestor with great apes.

Timescales of massive human entrainment

The past two decades have seen an upsurge of interest in the collective behaviors of complex systems composed of many agents entrained to each other and to external events. In this paper, we extend the concept of entrainment to the dynamics of human collective attention. We conducted a detailed investigation of the unfolding of human entrainment--as expressed by the content and patterns of hundreds of thousands of messages on Twitter--during the 2012 US presidential debates. By time-locking these data sources, we quantify the impact of the unfolding debate on human attention at three time scales. We show that collective social behavior covaries second-by-second to the interactional dynamics of the debates: A candidate speaking induces rapid increases in mentions of his name on social media and decreases in mentions of the other candidate. Moreover, interruptions by an interlocutor increase the attention received. We also highlight a distinct time scale for the impact of salient content during the debates: Across well-known remarks in each debate, mentions in social media start within 5-10 seconds after it occurs; peak at approximately one minute; and slowly decay in a consistent fashion across well-known events during the debates. Finally, we show that public attention after an initial burst slowly decays through the course of the debates. Thus we demonstrate that large-scale human entrainment may hold across a number of distinct scales, in an exquisitely time-locked fashion. The methods and results pave the way for careful study of the dynamics and mechanisms of large-scale human entrainment.

Iconic Prosody in Story Reading

Recent experiments have shown that people iconically modulate their prosody corresponding with the meaning of their utterance (e.g., Shintel et al., 2006). This article reports findings from a story reading task that expands the investigation of iconic prosody to abstract meanings in addition to concrete ones. Participants read stories that contrasted along concrete and abstract semantic dimensions of speed (e.g., a fast drive, slow career progress) and size (e.g., a small grasshopper, an important contract). Participants read fast stories at a faster rate than slow stories, and big stories with a lower pitch than small stories. The effect of speed was distributed across the stories, including portions that were identical across stories, whereas the size effect was localized to size-related words. Overall, these findings enrich the documentation of iconicity in spoken language and bear on our understanding of the relationship between gesture and speech.

Language understanding is grounded in experiential simulations: a response to Weiskopf

Several disciplines within the cognitive sciences have advanced the idea that people comprehend the actions of others, including the linguistic meanings they communicate, through embodied simulations where they imaginatively recreate the actions they observe or hear about. This claim has important consequences for theories of mind and meaning, such as that people's use and interpretation of language emerges as a kind of bodily activity that is an essential part of ordinary cognition. Daniel Weiskopf presents several arguments against the idea that experiential simulations play a major role in immediate language use and meaning. We offer several rebuttals to Weiskopf, in which we critique his interpretation of simulation theory, present additional psycholinguistic evidence supportive of the simulation perspective, and suggest that a more traditional theory of linguistic meaning and processing has little psychological and empirical validity.

Chromosomal aberrations and gene expression profiles in non-small cell lung cancer

Alterations in genomic content and changes in gene expression levels are central characteristics of tumors and pivotal to the tumorigenic process. We analyzed 23 non-small cell lung cancer (NSCLC) tumors by array comparative genomic hybridization (array CGH). Aberrant regions identified included well-characterized chromosomal aberrations such as amplifications of 3q and 8q and deletions of 3p21.31. Less frequently identified aberrations such as amplifications of 7q22.3-31.31 and 12p11.23-13.2, and previously unidentified aberrations such as deletion of 11q12.3-13.3 were also detected. To enhance our ability to identify key acting genes residing in these regions, we combined array CGH results with gene expression profiling performed on the same tumor samples. We identified a set of genes with concordant changes in DNA copy number and expression levels, i.e. overexpressed genes located in amplified regions and underexpressed genes located in deleted regions. This set included members of the Wnt/beta-catenin pathway, genes involved in DNA replication, and matrix metalloproteases (MMPs). Functional enrichment analysis of the genes both overexpressed and amplified revealed a significant enrichment for DNA replication and repair, and extracellular matrix component gene ontology annotations. We verified the changes in expressions of MCM2, MCM6, RUVBL1, MMP1, MMP12 by real-time quantitative PCR. Our results provide a high resolution map of copy number changes in non-small cell lung cancer. The joint analysis of array CGH and gene expression analysis highlights genes with concordant changes in expression and copy number that may be critical to lung cancer development and progression.

Do hyperoxaemia and hypocapnia add to the risk of brain injury after intrapartum asphyxia?

BACKGROUND

Episodes of hyperoxaemia and hypocapnia, which may contribute to brain injury, occur unintentionally in severely asphyxiated neonates in the first postnatal hours.

OBJECTIVE

To determine whether hyperoxaemia and/or hypocapnia during the first 2 hours of life add to the risk of brain injury after intrapartum asphyxia.

METHODS

Retrospective cohort study in term infants with post-asphyxial hypoxic ischaemic encephalopathy (HIE) born between 1985 and 1995. Severe and moderate hyperoxaemia were defined as Pao(2) >26.6 and Pao(2) >13.3 kPa (200 and 100 mm Hg). Severe and moderate hypocapnia were defined as Paco(2) <2.6 and Paco(2) <3.3 kPa (20 and 25 mm Hg). Adverse outcome ascertained by age 24 months was defined as death, severe cerebral palsy, or any cerebral palsy with blindness, deafness, or developmental delay. With outcome as the dependent variable, multivariate analyses were performed including hyperoxaemic and hypocapnic variables, and factors adjusted for initial disease severity.

RESULTS

Of 244 infants, 218 had known outcomes, 127 of which were adverse (64 deaths, 63 neurodevelopmental deficits). Multivariate analyses showed an association between adverse outcome and episodes of severe hyperoxaemia (odds ratio (OR) 3.85, 95% confidence interval (CI) 1.67 to 8.88, p = 0.002), and severe hypocapnia (OR 2.34, 95% CI 1.02 to 5.37, p = 0.044). The risk of adverse outcome was highest in infants who had both severe hyperoxaemia and severe hypocapnia (OR 4.56, 95% CI 1.4 to 14.9, p = 0.012).

CONCLUSIONS

Severe hyperoxaemia and severe hypocapnia were associated with adverse outcome in infants with post-asphyxial HIE. During the first hours of life, oxygen supplementation and ventilation should be rigorously controlled.

Multiorgan dysfunction in infants with post-asphyxial hypoxic-ischaemic encephalopathy

BACKGROUND

Multiorgan dysfunction (MOD) is one of four consensus based criteria for the diagnosis of intrapartum asphyxia. The theoretical concept behind MOD is the diving reflex (conservation of blood flow to vital organs at the cost of non-vital organs).

OBJECTIVES

To assess the patterns of involvement of each major organ/system and combinations of involvement in infants with post-asphyxial hypoxic-ischaemic encephalopathy (HIE), and to describe this in relation to long term outcome.

DESIGN

Retrospective cohort study.

SETTING

Regional tertiary neonatal intensive care unit at the Hospital for Sick Children, Toronto, Canada.

PATIENTS

Term neonates with post-intrapartal asphyxial HIE assessed for kidney, cardiovascular system, lung, and liver function.

OUTCOME

Death and presence or absence of severe neurodevelopmental disability.

RESULTS

Out of 130 of 144 eligible infants with outcome data, 80 (62%) had severe adverse outcome and 50 (38%) had good outcome. All infants had evidence of MOD (at least one organ dysfunction in addition to HIE). Renal, cardiovascular, pulmonary, and hepatic dysfunction was present in 58-88% of infants with good outcome and 64-86% of infants with adverse outcome.

CONCLUSIONS

MOD was present in all the infants with severe post-asphyxial HIE. However, there was no association between MOD and outcome in these infants. No relation between individual or combinations of organ involvements and long term outcomes was observed.

Recovery of metabolic acidosis in term infants with postasphyxial hypoxic-ischemic encephalopathy

AIMS

To describe the base deficit (BD) values and the rate of postnatal recovery of the BD of infants with hypoxic ischemic encephalopathy due to intrapartum asphyxia; and to explore the relationships between the rate of recovery of BD, severe adverse outcome and different time patterns (acute total vs prolonged partial) of asphyxia.

METHODS

Clinical and laboratory data were collected from the neonatal period (n = 244) and outcome data to a minimal age of 1 y (n = 218). Rates of recovery of BD were described in four 60 min blocks of time. The values of rate of recovery were compared between the outcome groups, ignoring correlation structure within subjects and with adjustment by the generalized estimating equations method.

RESULTS

The BD normalized within 4 h of birth in all but 9 of 244 infants. The rates of recovery of BD in infants with good and severe adverse outcome respectively were 0.11 [95% confidence interval (95% CI) 0.07, 0.14] and 0.09 (95% CI 0.07, 0.12) mmol l(-1) min(-1) over the first 4 h after birth. The rates of recovery were similar with or without buffer therapy, and after acute near-total and prolonged partial asphyxia.

CONCLUSION

The BD in the great majority of infants with severe intrapartum asphyxia normalizes within 4 h of birth. The BD recovery rate of infants with adverse outcomes was similar to those with relatively good outcome. The different time patterns of asphyxial episode were not associated with differential recovery profiles.

Prognostic value of EEG in neonatal bacterial meningitis

The contribution of electroencephalogram (EEG) findings early in the course of neonatal bacterial meningitis to the prediction of severe adverse outcome was assessed in a retrospective cohort study. Infants had known outcomes to 1 year of age and an EEG performed during the first week of illness. EEGs were subclassified as follows: overall EEG description, background activity, presence of positive rolandic sharp waves, presence of seizure activity, and presence of focal abnormal activity. EEG patterns predictive of severe adverse outcome were identified by univariate and multivariate analyses. Of 101 infants admitted with bacterial meningitis, 37 had an EEG performed. Of the 37 infants, 21 had adverse outcomes; nine infants died, and 12 infants had moderate or severe disability. EEG background activity and overall EEG description were identified as predictors of adverse outcome; multivariate analysis indicated that the latter was a stronger predictor (sensitivity 88%, specificity 90%). Infants with normal or mildly abnormal EEGs had good outcomes whereas those with moderate to markedly abnormal EEGs died or survived with adverse outcome. The accuracy of predictions increased when EEGs were repeated. In a high-risk population of infants with bacterial meningitis, moderate-to-markedly abnormal EEG reliably predicts adverse outcome.

Predicting the outcome of neonatal bacterial meningitis

OBJECTIVE

To build predictive models of severe adverse outcome at various times in the course of neonatal bacterial meningitis.

STUDY DESIGN

Retrospective cohort study with follow-up to a minimum age of 1 year of term and near-term infants, admitted between 1979 and 1998 to a regional tertiary care center. Predictors of adverse outcome detectable at 1 year of age (death or moderate or severe neurosensory impairment) were identified by univariate analysis. Independent predictors of adverse outcome were identified by multivariate analysis. Predictive tree models were constructed at 12, 24, 48, and 96 hours after admission and at discharge.

RESULTS

Of 101 infants admitted with definitive bacterial meningitis, 13 died and 17 had moderate or severe disability at 1 year of age. Outcomes are known for all patients, to 1 year of age. Twelve hours after admission the important predictors of adverse outcome were presence of seizures, presence of coma, use of inotropes, and leukopenia (sensitivity: 68%; specificity: 100%). At 96 hours the predictors were seizure duration of >72 hours, presence of coma, use of inotropes, and leukopenia (sensitivity: 88%; specificity: 99%).

CONCLUSIONS

Most infants at risk for adverse outcome can be identified within 12 hours of admission. Duration of seizures for >72 hours, presence of coma, use of inotropes, and leukopenia were the most important predictors of adverse outcome. Although these models have good predictive accuracy, they need to be validated in a contemporary cohort in large multicenter studies.

Disability outcomes in a worker's compensation population: surgical versus nonsurgical treatment of carpal tunnel syndrome

A retrospective record review of patients with occupational carpal tunnel syndrome, nerve conduction velocity studies, and a closed Workers' Compensation case was undertaken to compare the outcome of surgical versus nonsurgical treatment with respect to disability and return to work status. Between January 1, 1991, and December 31, 1993, 182 patients who met the inclusion criteria were identified. Surgical release of the carpal tunnel was performed in 57% of patients and the other 43% were treated conservatively. Overall, 82% of patients returned to full work status, whereas 18% had duty modifications. Surgical treatment decreased the rate of duty modifications and disability ratings compared with nonsurgical treatment and reduced the odds of incurring disability. Severity of carpal tunnel syndrome was also a significant factor affecting disability. Despite the generally held belief that the outcome of treatment of occupational carpal tunnel syndrome is poor, the present study shows that both surgical and nonsurgical treatment is effective. However, patients treated with surgery had decreased disability when compared with those who were treated conservatively.

A randomized trial of 72- versus 24-hour intravenous tubing set changes in newborns receiving lipid therapy

OBJECTIVE

To compare the microbial contamination rate of infusate in the intravenous tubing of newborns receiving lipid therapy, replacing the intravenous delivery system at 72-hour versus 24-hour intervals.

DESIGN

Infants requiring intravenous lipid therapy were randomly assigned to have intravenous sets changed on a 72- or a 24-hour schedule, in a 3:1 ratio, in order to compare the infusate contamination rates in an equivalent number of tubing sets.

SETTING

A 35-bed, teaching, referral, neonatal intensive-care unit (NICU).

PARTICIPANTS

All neonates admitted to the NICU for whom intravenous lipid was ordered.

METHODS

Patients were randomized in pharmacy, on receipt of the order for intravenous lipid therapy, to either 72- or 24-hour administration set changes, and followed until 1 week after discontinuation of lipids or discharge from the NICU. Microbial contamination of the infusate was assessed in both groups at the time of administration set changes. Contamination rates were analyzed separately for the lipid and amino acid-glucose tubing sets. Patient charts were reviewed for clinical and epidemiological data, including birth weight, gestational age, gender, age at start of lipid therapy, duration of parenteral nutrition, and type of intravenous access.

RESULTS

During the study period, 1,101 and 1,112 sets were sampled in the 72- and 24-hour groups, respectively. Microbial contamination rates were higher in the 72-hour group than the 24-hour group for lipid infusions (39/1,101 [3.54%] vs 15/1,112 [1.35%]; P=.001) and for amino acid infusions (12/1,093 [1.10%] vs 4/1,103 [0.36%]; P=.076). Logistic regression analysis controlling for birth weight, gestational age, and type of venous access showed that only the tubing change interval was significantly associated with lipid set contaminations (odds ratio, 2.69; P=.0013). The rate of blood cultures ordered was higher in the 72- versus the 24-hour group (6.11 vs 4.99 per 100 patient days of total parenteral nutrition; P=.017), and a higher proportion of infants randomized to the 72-hour group died (8% vs 4%; P=.05), although the excess deaths could not clearly be attributed to bacteremia.

CONCLUSION

Microbial contamination of infusion sets is significantly more frequent with 72- than with 24-hour set changes in neonates receiving lipid solutions. This may be associated with an increased mortality rate.

Delphi-panel analysis of appropriateness of high-dose therapy and bone marrow autotransplants in newly diagnosed multiple myeloma

There is controversy whether high-dose therapy and a bone marrow autotransplant or conventional chemotherapy is a better treatment for newly diagnosed multiple myeloma. Data from 1 comparative study and 1 randomized trial provide insufficient subject-level data to advise specific people whether to have an autotransplant. We analyzed appropriate use of high-dose therapy and bone marrow autotransplants in people with newly diagnosed, multiple myeloma using a modified Delphi-panel group judgment process. The panel consisted of 9 myeloma experts from diverse geographic sites and practice settings who reviewed Boolean MEDLINE searches of multiple myeloma and chemotherapy or autotransplants. The panel rated a metric of 64 clinical setting developed by permuting age, performance score, disease-stage and disease-related prognostic variables and response to initial therapy. Each panelist rated appropriateness of high-dose therapy and an autotransplant versus conventional-dose chemotherapy on a 9-point ordinal scale (1, most inappropriate, 9, most appropriate). An appropriateness index was developed based on median rating and amount of disagreement. Relationship of appropriateness indices to the permuted clinical variables was considered by analysis of variance and recursive partitioning. Autotransplants were rated appropriate in persons <55 years old with stage 3 disease and a complete or partial response or stable disease after initial chemotherapy, inappropriate in persons with stage 1 or 2 disease, a performance score <70% and a complete or partial response or stable disease after initial chemotherapy and uncertain in all other settings.

Symptomatic hypoglycemia in otherwise healthy, breastfed term newborns

Transient symptomatic neonatal hypoglycemia, a diagnosis that is made in the neonatal nursery, is not usually associated with apparently normal infants who have been discharged from hospital. We describe 3 such cases that presented at home on day 3 of life with seizures or life-threatening apneas. We postulate that early discharge of apparently normal infants with marginal nutritional or metabolic adaptation, may expose some infants to postdischarge (but still neonatal) hypoglycemia and its attendant risks.

Facilitating edema resolution with a foot pump after calcaneus fracture

OBJECTIVES

To determine whether the use of a foot pump (intermittent pneumatic pedal compression device) in patients with excessive edema precluding surgery after acute fracture of the calcaneus leads to more rapid resolution of the edema.

DESIGN

Prospective randomized setting. Standard hospital in-patient ward at a Level I trauma center.

PATIENTS

Those patients with excessive edema precluding operative intervention upon admission after an intraarticular calcaneus fracture who signed an informed consent participated in the study. Twenty-eight patients were enrolled and completed the study: thirteen patients in the foot pump group and fifteen patients in the control group.

INTERVENTION

In the control group, patients had a bulky compression dressing, posterior splint, and elevation while awaiting surgery. In the study group, the patients had a foot pump applied to the foot with a posterior splint and elevation while awaiting surgery.

MAIN OUTCOME MEASUREMENTS

The volumetric change of the foot at twenty-four-hour intervals for up to seventy-two hours in both the control and study groups.

RESULTS

All thirteen patients tolerated the foot pump. The differences in the volume between Day I (baseline) and Day 2 for the foot pump and control groups were minus forty and plus seventy-six milliliters, respectively (p = 0.02). Between Days 1 and 3, the differences were minus ninety-six milliliters for the foot pump group and plus thirty-seven milliliters for the control group (p = 0.02).

CONCLUSIONS

A significant progressive decrease in the foot volume was noted during the first forty-eight hours after application of the foot pump in patients with excessive edema precluding operative fixation of a calcaneus fracture upon presentation. The pump was well tolerated by all the patients in the study group. Thus, we believe the pump serves as a useful adjunct in the preoperative edema resolution following these complicated fractures.

Outcomes of extremely premature infants related to their peak serum bilirubin concentrations and exposure to phototherapy

OBJECTIVES

To analyze, in extremely low birth weight infants, associations between peak bilirubin concentration and evidence of brain damage, and between peak bilirubin concentration and blindness attributable to retinopathy of prematurity.

METHODS

Retrospective study of 128 infants of </=800 g birth weight and </=27 weeks gestation born between 1980 and 1989 and discharged from a tertiary neonatal intensive care unit. After screening analyses, multivariable analyses were conducted to identify associations between blindness and peak bilirubin concentration (dichotomized at different levels to create 3 binary variables), and between severe adverse neurodevelopmental outcome at 18 months postterm age and peak bilirubin levels.

RESULTS

Of 128 18-month survivors, 15 had severe visual loss attributable to retinopathy of prematurity, 21 had neurodevelopmental deficit, and 5 were deaf. Visual loss was significantly associated with low-peak serum bilirubin concentration (<9.4 mg/dL (<160 micromol/L) versus >/=9.4 mg/dL (odds ratio [OR] confidence interval [CI] 4.48 [1.15-17.43])), low gestational age (OR [CI] per week 1.95 [1.05-3.63]), and longer duration of phototherapy (OR [CI] per 10 hours 1.17 [1.02-1.33]). The association of neurodevelopmental impairment with grades 3 and 4 intraventricular hemorrhage was statistically significant (OR 5.39 [1.83-15.84]), but with high-peak serum bilirubin concentration >/=11.7 mg/dL (>/=200 micromol/L), was not significant (OR 2.89 [0. 87-9.53]).

CONCLUSIONS

In these infants, prolonged phototherapy and low-peak serum bilirubin concentrations were associated with severe visual loss attributable to retinopathy of prematurity. The findings should be interpreted with caution until the evidence is reinforced in other patient populations.

Anti-myeloma activity of pamidronate in vivo

Two patients with progressive myeloma were treated with pamidronate disodium every 2-4 weeks. Pamidronate therapy resulted in a significant reduction of marrow plasmacytosis and plasma cell labelling index (PCLI), together with durable (> or = 20 months) stabilization of immunoglobulin (Ig) levels and an increase in bone mineral density in the first patient and > 50%, reduction in Ig levels and bone marrow plasmacytosis in the second. This, to our knowledge, is the first report of an anti-myeloma effect of bisphosphonates in humans and provides evidence that a therapeutic intervention largely directed at the myeloma microenvironment may alter the natural history of the disease.

Perceptions of academic strategies and competence in students with learning disabilities

Research findings regarding general self-concept, academic self-concept, and self-awareness in students with learning disabilities have varied, and results are still inconclusive regarding the consistency between students' and teachers' judgments of academic performance. The current study focuses on students' and teachers perceptions of the students' strategy use and performance in nine different academic and organizational domains. Six hundred sixty-three students and their 57 teachers were involved in the study. Findings indicated that the students with learning disabilities considered themselves appropriately strategic and competent in the five domains of reading, writing, spelling, math, and organization. These students also rated their academic performance and organization as average to above-average in seven of nine domains, with the exception of checking and planning their work. Nevertheless, the self-ratings of the students with learning disabilities were still significantly lower than the self-ratings of average achievers in virtually all domains. The second major set of findings revealed a sharp discrepancy between the self-assessments of the students with learning disabilities and their teachers' judgments. Teachers rated the students with learning disabilities as weak in their strategy use and below-average in their performance in all nine academic and organizational domains. Finally, gender differences were not evident in eight of the nine domains. These results have added to the increasing body of literature indicating that students with learning disabilities frequently perceive themselves as capable and effective and often rate themselves as academically stronger than their teachers judge them to be.

Autopsy in a neonatal intensive care unit: utilization patterns and associations of clinicopathologic discordances

OBJECTIVES

(1) To develop methods to describe autopsy utilization patterns in a neonatal intensive care unit. (2) To identify classes of patients likely to have clinicopathologic concordance or discordance.

METHODS

Five hundred forty-five consecutive neonatal intensive care unit deaths (338 autopsied, rate 62%) in a regional tertiary/quaternary care neonatal intensive care unit for referred infants (65,000 annual births) were classified in six clinical diagnostic groups (anomalies, cardiac anomalies, hypoxic ischemic encephalopathy, prematurity and its complications, infections, and other) and rated in three levels of certainty of clinical diagnosis as "gold standard" certainty, almost complete certainty, and less certain than the latter. Clinicopathologic discordances were rated in three classes using clinical, pathologic, and multidisciplinary mortality conference records. The proportions of autopsied cases, cases with major discordances, and cases with no discordances were compared and analyzed in relation to diagnostic group and level of certainty.

RESULTS

Performance of autopsy was associated with clinical diagnostic uncertainty (p = 0.008). Major discordances with implications for outcome (Class I) were found in 3%, and without implications for outcome (Class II) in 15% of cases; 42% of cases had no discordances. Major discordance rate varied inversely with the degree of diagnostic certainty (p = 0.000) and varied among clinical groups.

CONCLUSIONS

(1) Autopsy was used most for cases with potential for high yields. (2) Clinicopathologic discordances were more frequent and important in certain clinical diagnostic groups (prematurity, other) and with high levels of diagnostic uncertainty. When the diagnostic "gold standard" is available during life, autopsy will provide little information.

Predicting the outcome of postasphyxial hypoxic-ischemic encephalopathy within 4 hours of birth

OBJECTIVE

To build models that predict severe adverse outcome within 4 hours of birth in patients with postasphyxial hypoxic-ischemic encephalopathy. The goal was to develop models for selecting patients for therapeutic trials of neuroprotective medications.

STUDY DESIGN

Retrospective cohort study with follow-up to a minimum age of 12 months of 164 "outborn" term infants admitted to a tertiary neonatal intensive care unit, and 14 "inborn" term infants in the two tertiary perinatal centers in a regionalized setting. After performing univariate screening tests, multivariate models of association between risk factors and "severe adverse outcome" (death or major neurosensory impairment) were constructed.

RESULTS

Of 178 infants with postasphyxial hypoxic-ischemic encephalopathy of defined severity admitted consecutively between 1985 and 1992, 48 died, 40 survived with major neurosensory impairment, and 13 were lost to follow-up. The important predictors of severe adverse outcome in the first 4 hours were delayed onset of breathing, administration of chest compressions, and seizures. At 60 minutes of age, based on predicted probabilities of > 0.50, the sensitivity of the predictive model was 85% and specificity 68%. The parameter estimates of the predictive models are reported.

CONCLUSIONS

Age of onset of breathing, administration of chest compressions, and age of onset of seizures were the most important variables predictive of adverse outcome in this study. Although fairly sensitive and specific, these predictive models should be applied with caution. To build more accurate models, a template for the conduct of a large, multicenter prospective study is provided.

Relationships between myoelectric activity, strength, and MRI of lumbar extensor muscles in back pain patients and normal subjects

Eight normal individuals and eight patients with chronic back pain were evaluated. They undertook a treatment program lasting 8 weeks, with two exercise sessions each week. Myoelectric activity, lumbar extensor strength, and cross-sectional magnetic resonance imaging appearance of the lumbar paraspinal extensor muscles was assessed at the beginning and end of the program. Initial baseline and final extensor strength measurements were done isometrically at seven points through full range. Surface myoelectric activity was monitored during both flexion and extension exercise. Subsequently, electromyographic (EMG) signals were analyzed for mean frequency (MPF) and amplitude (RMS). An average functional improvement of 65% and reduction of pain complaint of 41% occurred in the eight patients with chronic low back pain. Extensor strength improved an average of 48% contrasted to 6% for the normal subjects. Four patients who showed severe fatty infiltration in the extensors had a decrease in the degree of infiltration and no change in muscle mass. Changes in fatty infiltration did not correlate with strength changes. The dynamic EMG changes documented a decrease in amplitude (RMS) and a smaller decrease in frequency (MPF) for the same resistance when used at the beginning and end of the program. Structural changes in the muscles are not always needed to achieve strength gains or symptomatic improvement.

Congenital hemangiopericytoma/infantile myofibromatosis: radical surgery versus a conservative "wait and see" approach

Infantile/congenital hemangiopericytoma, although sharing many similar histological features with adult hemangiopericytoma, has a much better prognosis. Nevertheless, most cases described in the literature were pursued by radical surgery with or without adjuvant chemotherapy. We describe a neonate who presented with a huge mass in the right gluteus, 6 x 5 x 4 cm, and a small ventral abdominal mass. The masses were confirmed on biopsy according to light microscopy, immunohistochemistry, and electron microscopy as congenital hemangiopericytoma. They shrank spontaneously within 2 weeks and vanished within 2 months. We present a hypothesis that masses appearing in the neonatal period with this histology and with no life-endangering pressure on vital organs should routinely be dealt with conservatively.

Intermittent pneumatic pedal compression and edema resolution after acute ankle fracture: a prospective, randomized study

Thirty patients with an acute Weber B or C ankle fracture were enrolled after signing an informed consent. Fifteen patients were randomized to a control group where they received a posterior splint, ice, and elevation before surgery. Fifteen patients were randomized to a pneumatic pedal compression group where they received the same treatment plus a pneumatic pedal compression device which was used full-time before surgery. Baseline volumetric measurements of the injured foot were obtained, followed by measurements at 24-hour increments until surgery. On average, the patients in the pneumatic pedal compression group had an 88 mL decrease in volume in the first 24 hours versus a 33 mL increase in the control group (P < 0.03) and a 31 mL decrease in the first 48 hours of treatment versus a 32 mL increase for the control group (P < 0.05). The pneumatic pedal compression was well tolerated by the majority of patients (only one did not tolerate its use because of pain) and, we believe, serves as a useful adjunct in preoperative edema resolution after ankle fracture.

Clinicopathological correlations in postasphyxial organ damage: a donor organ perspective

OBJECTIVES

1) To assess pathology in the heart, kidneys, lungs, liver, and intestine in babies dying of postasphyxial hypoxic ischemic encephalopathy (HIE), and their suitability for organ transplantation. 2) To analyze the correlation between in vivo clinical markers of collateral organ damage and autopsy findings.

STUDY DESIGN

Retrospective cohort study of 58 infants who died of postasphyxial HIE and had autopsies during 1985 to 1994. Collateral organ damage was evaluated clinically and pathologically, and the results compared.

RESULTS

Severe pathological changes were observed in 6% to 62% of the five organs studied; 59% of the four major organs had either minor or no pathology. The sensitivity of the clinical predictors ranged from 69% to 100%, and specificity from 50% to 97%.

CONCLUSIONS

The organs of newborns dying of severe HIE may be suitable for use as donor organs; predictions of their suitability were most accurate for liver, kidney, and lungs, and least accurate for the heart.

The impact of early obstetric discharge on newborn health care

The impetus for shorter hospital stay of mother and newborn infant after delivery is based on economic constraints and parental preference. Earlier published studies did not demonstrate any increase in morbidity rate with shorter stay, but these studies were limited by methodologic flaws and biases that limited the validity and generalizability of the conclusions. More recent studies showed that readmission rates increased with shorter stay and that the severity of illness of readmitted infants may have increased. In addition, the interpretation of current newborn screening tests may not be applicable when performed prior to early discharge. In light of recent changes in neonatal hospital length of stay, a careful review and update of current guidelines and practices for newborn care are required.

Association between duration of neonatal hospital stay and readmission rate

OBJECTIVE

A recent rapid decrease in the duration of neonatal hospital stay in Ontario, Canada, enabled us to study the association between healthy infants' age at neonatal hospital discharge and subsequent readmission rates.

DESIGN

(1) Population-based and (2) single hospital-based retrospective studies.

SETTING AND STUDY POPULATION

(1) A total of 920,554 healthy infants with a birth weight of 2500 gm or more, born in Ontario from 1987 to 1994. (2) Infants with a birth weight of 2500 gm or more, born during the same period, and readmitted before 15 days from home to the Hospital for Sick Children for jaundice or dehydration.

MEASUREMENT

Duration of neonatal stay in the hospital and readmission rates were measured, and diagnostic codes were analyzed. Severity of illness was evaluated in infants readmitted to our hospital.

RESULTS

In Ontario the mean length of stay decreased from 4.5 days to 2.7 days (p = 0.000), and the readmission rate during the first 2 weeks of life increased from 12.9 to 20.7 per 1000 (p = 0.000). Increased rates of readmission were most marked for jaundice and dehydration. The infants readmitted to our hospital had evidence of increased severity of illness as indicated by higher serum bilirubin and sodium concentrations. Two deaths occurred in infants with hypernatremic dehydration, one in 1992-1993 and another in 1993-1994.

CONCLUSIONS

In Ontario, shorter neonatal hospital stay was associated with increased readmission rates for conditions that may not give rise to symptoms or signs on days 1 to 3 of life. In our hospital the severity of jaundice and dehydration in readmitted infants increased. The severity-of-illness data raise the question of whether shorter neonatal hospital stay of apparently healthy infants is always safe. Decisions to discharge infants should be based on rigorous evaluation of individual infants.

High cervical spinal cord injury in neonates delivered with forceps: report of 15 cases

OBJECTIVE

To inform obstetricians of a serious complication of forceps rotations of 90 degrees or more--high cervical spinal cord injury in neonates.

METHODS

We reviewed the obstetric aspects of 15 cases of high cervical spinal cord birth injury diagnosed during 1982-1994 at two tertiary-care children's hospitals in Canada.

RESULTS

The common feature in all cases was a forceps cephalic delivery, almost always a rotation of 90 degrees or more from the occipitoposterior or occipitotransverse position.

CONCLUSION

High cervical spinal cord injury in neonates is a rare but specific complication of forceps rotation.