Many people have argued that the evolution of the human language faculty cannot be explained by Darwinian natural selection. Chomsky and Gould have suggested that language may have evolved as the by-product of selection for other abilities or as a consequence of as-yet unknown laws of growth and form. Others have argued that a biological specialization for grammar is incompatible with every tenet of Darwinian theory – that it shows no genetic variation, could not exist in any intermediate forms, confers no selective advantage, and would require more evolutionary time and genomic space than is available. We examine these arguments and show that they depend on inaccurate assumptions about biology or language or both. Evolutionary theory offers clear criteria for when a trait should be attributed to natural selection: complex design for some function, and the absence of alternative processes capable of explaining such complexity. Human language meets these criteria: Grammar is a complex mechanism tailored to the transmission of propositional structures through a serial interface. Autonomous and arbitrary grammatical phenomena have been offered as counterexamples to the position that language is an adaptation, but this reasoning is unsound: Communication protocols depend on arbitrary conventions that are adaptive as long as they are shared. Consequently, language acquisition in the child should systematically differ from language evolution in the species, and attempts to analogize them are misleading. Reviewing other arguments and data, we conclude that there is every reason to believe that a specialization for grammar evolved by a conventional neo-Darwinian process.

http://www.biolinguagem.com/ling_cog_cult/pinker_bloom_1990_naturallanguage_naturalselection.pdf

Natural language and natural selection

ObjectiveThis update of a 2004 guideline codeveloped by the American Academy of Otolaryngology—Head and Neck Surgery Foundation, the American Academy of Pediatrics, and the American Academy of Family Physicians, provides evidence-based recommendations to manage otitis media with effusion (OME), defined as the presence of fluid in the middle ear without signs or symptoms of acute ear infection. Changes from the prior guideline include consumer advocates added to the update group, evidence from 4 new clinical practice guidelines, 20 new systematic reviews, and 49 randomized control trials, enhanced emphasis on patient education and shared decision making, a new algorithm to clarify action statement relationships, and new and expanded recommendations for the diagnosis and management of OME.PurposeThe purpose of this multidisciplinary guideline is to identify quality improvement opportunities in managing OME and to create explicit and actionable recommendations to implement these opportunities in clinical pra...

https://journals.sagepub.com/doi/pdf/10.1177/0194599815623467

Clinical Practice Guideline Otitis Media with Effusion (Update)

THE POSITION STATEMENT The Joint Committee on Infant Hearing (JCIH) endorses early detection of and intervention for infants with hearing loss. The goal of early hearing detection and intervention (EHDI) is to maximize linguistic competence and literacy development for children who are deaf or hard of hearing. Without appropriate opportunities to learn language, these children will fall behind their hearing peers in communication, cognition, reading, and social-emotional development. Such delays may result in lower educational and employment levels in adulthood.1 To maximize the outcome for infants who are deaf or hard of hearing, the hearing of all infants should be screened at no later than 1 month of age. Those who do not pass screening should have a comprehensive audiological evaluation at no later than 3 months of age. Infants with confirmed hearing loss should receive appropriate intervention at no later than 6 months of age from health care and education professionals with expertise in hearing loss and deafness in infants and young children. Regardless of previous hearing-screening outcomes, all infants with or without risk factors should receive ongoing surveillance of communicative development beginning at 2 months of age during well-child visits in the medical home.2 EHDI systems should guarantee seamless transitions for infants and their families through this process.

/pdf/year-2007-position-statement-principles-and-guidelines-for-1m07julcke.pdf

Year 2007 position statement: Principles and guidelines for early hearing detection and intervention programs

The sequence of neurophysiological processes elicited in the auditory system by a sound is analyzed in search of the stage at which the processes carrying sensory information cross the borderline beyond which they directly underlie sound perception. Neurophysiological data suggest that this transition occurs when the sensory input is mapped onto the physiological basis of sensory memory in the auditory cortex. At this point, the sensory information carried by the stimulus-elicited process corresponds, for the first time, to that contained by the actual sound percept. Before this stage, the sensory stimulus code is fragmentary, lacks the time dimension, cannot enter conscious perception, and is not accessible to top-down processes (voluntary mental operations). On these grounds, 2 distinct stages of auditory sensory processing, prerepresentational and representational, can be distinguished.

The concept of auditory stimulus representation in cognitive neuroscience.

Although most recent multitalker research has emphasized the importance of binaural cues, monaural cues can play an equally important role in the perception of multiple simultaneous speech signals. In this experiment, the intelligibility of a target phrase masked by a single competing masker phrase was measured as a function of signal-to-noise ratio (SNR) with same-talker, same-sex, and different-sex target and masker voices. The results indicate that informational masking, rather than energetic masking, dominated performance in this experiment. The amount of masking was highly dependent on the similarity of the target and masker voices: performance was best when different-sex talkers were used and worst when the same talker was used for target and masker. Performance did not, however, improve monotonically with increasing SNR. Intelligibility generally plateaued at SNRs below 0 dB and, in some cases, intensity differences between the target and masking voices produced substantial improvements in performance with decreasing SNR. The results indicate that informational and energetic masking play substantially different roles in the perception of competing speech messages.

/pdf/informational-and-energetic-masking-effects-in-the-ln60xtz8tq.pdf

Informational and energetic masking effects in the perception of multiple simultaneous talkers.

Sensorineural hearing loss (SNHL) which is sudden in onset, fluctuating, and/or progressive complicates medical management, hearing aid selection, and individualized educational planning for a hearing-impaired child. In spite of multidisciplinary evaluation and intervention, a gradual decrease in auditory acuity may continue unabated in a significant number of cases. Intercurrent middle ear disease and inconsistent audiologic technique can account for threshold variation in some cases. The study population consisted of 229 children (132 boys; 97 girls) aged 1 to 19.9 years at first audiogram which revealed at least a mild degree of sensorineural hearing loss in one or both ears (35 unilateral), and who demonstrated threshold variation of 10 dB or more in at least one ear at one or more of the standard audiometric test frequencies (250, 500, 1000, 2000, 4000, and 8000 Hz) and were without concurrent middle ear disease (mean length of follow-up, 4.9 years; mean number of audiograms, 10.3). Of 365 ears demonstrating threshold variation of 10 dB or more, 22 (6%) had purely progressive losses without intercurrent upward fluctuation, 208 (57%) had fluctuating thresholds with gradually progressive losses, and 135 (37%) had intermittent threshold fluctuation without permanent deterioration. The probability of contralateral threshold fluctuation if one ear fluctuated was 0.91, while the probability of contralateral progressive SNHL if one ear progressed was 0.67. Demographic data, presumptive etiology, degree of initial SNHL, audiometric configuration, and symmetry of threshold variation were considered as potential predictors of the likelihood of threshold fluctuation and/or progression.

Fluctuating and/or progressive sensorineural hearing loss in children

Pediatric cochlear implantation is restricted to patients with stable, bilateral profound sensorineural hearing losses who derive no benefit from conventional amplification. Obtaining reliable audiologic thresholds in a young child with sudden or early-onset hearing loss can be challenging. This study examines the accuracy with which auditory brain-stem response evaluation can predict unaided and aided behavioral thresholds in a child with severe-to-profound hearing loss. Reliable behavioral thresholds were obtained on 119 children who had no measurable click-evoked auditory brainstem responses at instrumentation limits of 100 dB HLn. These data show that an absent auditory brainstem response at 100 dB HLn does not necessarily indicate the absence of measurable unaided hearing for test frequencies ranging from 250 Hz to 4000 Hz. Average aided thresholds of better than 60 dB were present in 43% of the children for 500, 1000, and 2000 Hz and in 53% for 500 and 1000 Hz. Therefore, the absence of a click-evoked auditory brainstem response at 100 dB HLn in a young child is not prima facie evidence of the child's cochlear implant candidacy.

Auditory brainstem response results as predictors of behavioral auditory thresholds in severe and profound hearing impairment

This study compared the reliability of a recently developed high-frequency audiometer (HFA) [Stevens et al., J. Acoust. Soc. Am. 81, 470-484 (1987)] with a less complicated system that uses supraaural earphones (Koss system). The new approach permits calibration on an individual basis, making it possible to express thresholds at high frequencies in dB SPL. Data obtained from 50 normal-hearing subjects, ranging in age from 10-60 years, were used to evaluate the effects on reliability of threshold variance, earpiece/earphone fitting variance, and the variance associated with the HFA calibration process. Without earpiece/earphone replacement, the reliability of thresholds for the two systems is similar. With replacement, the HFA showed poorer reliability than the Koss system above 11 kHz, largely due to errors in estimating the calibration function. HFA reliability is greater for subjects with valid calibration functions over the entire frequency range. When average correction factors are applied to the Koss data in an effort to convert threshold estimates to dB SPL, individual transfer functions are not represented accurately. Thus the benefit of being able to express thresholds at high frequencies in dB SPL must be weighed against the additional source of variability introduced by the HFA calibration process.

High-frequency audiometry: test reliability and procedural considerations.

A battery of eight auditory discrimination tests was designed to measure the primary dimension along which simple and complex sounds can be discriminated. Six of the tests, selected on the basis of data collected in an earlier 22‐subtest version of the battery [D. M. Johnson, J. K. Jensen, and C. S. Watson, J. Acoust. Soc. Am. Suppl. 1 67, S52 (1980)], use tonal stimuli: tests of frequency, intensity, and duration discrimination, using single tones, and tests of rhythm, temporal order, and tonal‐pattern discrimination using multitone sequences. Two additional tests employ speech sounds: a syllable order discrimination test and a modification of one portion‐ of a nonsense syllable identification test [J. R. Dubno and H. Levitt, J. Acoust. Soc. Am. 69, 249–261 (1981)]. The tape‐recorded tests were designed to be administered to groups of listeners in a free field, moderately low‐reverberation environment. with responses recorded on printed forms. Seventy‐two modified 2AFC trials, distributed among eight sti...

An auditory discrimination test battery

Early identification of children with sensorineural hearing loss (SNHL), coupled with the provision of appropriate conventional amplification constitute important elements of a (re)habilitative strategy. Often overlooked, however, is the problem posed by recurrent and chronic middle ear disease in the child with coexisting SNHL. This study focuses on 437 (237 boys and 200 girls) consecutive patients with bilateral SNHL, in the moderate range or poorer, who were diagnosed prior to age 5 years at Boys Town National Research Hospital. The mean threshold shift with effusion was 25.0 dB at 250 Hz, 28.5 dB at 500 Hz, 29.5 dB at 1000 Hz, 24.5 dB at 2000 Hz, and 27.5 dB at 4000 Hz. During a median follow-up period of 3.21 years, 154 (35.2%) of these children required surgical placement of tympanostomy tubes because of the severity of middle ear disease and its impact on auditory acuity. Accurate determination of the degree and audiologic configuration of a SNHL may be seriously hindered by a coexisting middle ear effusion. If initial findings indicate the presence of a middle ear effusion, measures of auditory function must be repeated after the effusion has been resolved by medical and/or surgical intervention.

William J. Kelly

Papers

Fluctuating and/or progressive sensorineural hearing loss in children

Auditory brainstem response results as predictors of behavioral auditory thresholds in severe and profound hearing impairment

High-frequency audiometry: test reliability and procedural considerations.

An auditory discrimination test battery

Middle ear disease in young children with sensorineural hearing loss