Reaction time for correct identification of vowels in consonant-vowel syllables and of vowel segments.

Reaction times for correct vowel identification were measured to determine the effects of intertrial intervals, vowel, and cue type. Thirteen adults with normal hearing, aged 20-38 years old, participated. Stimuli included three naturally produced syllables (/ba/ /bi/ /bu/) presented whole or segmented to isolate the formant transition or static formant center. Participants identified the vowel presented via loudspeaker by mouse click. Results showed a significant effect of intertrial intervals, no significant effect of cue type, and a significant vowel effect-suggesting that feedback occurs, vowel identification may depend on cue duration, and vowel bias may stem from focal structure.

The Use of Static and Dynamic Cues for Vowel Identification by Children Wearing Hearing Aids or Cochlear Implants.

OBJECTIVE: To examine vowel perception based on dynamic formant transition and/or static formant pattern cues in children with hearing loss while using their hearing aids or cochlear implants. We predicted that the sensorineural hearing loss would degrade formant transitions more than static formant patterns, and that shortening the duration of cues would cause more difficulty for vowel identification for these children than for their normal-hearing peers. DESIGN: A repeated-measures, between-group design was used. Children 4 to 9 years of age from a university hearing services clinic who were fit for hearing aids (13 children) or who wore cochlear implants (10 children) participated. Chronologically age-matched children with normal hearing served as controls (23 children). Stimuli included three naturally produced syllables (/ba/, /bi/, and /bu/), which were presented either in their entirety or segmented to isolate the formant transition or the vowel static formant center. The stimuli were presented to listeners via loudspeaker in the sound field. Aided participants wore their own devices and listened with their everyday settings. Participants chose the vowel presented by selecting from corresponding pictures on a computer screen. RESULTS: Children with hearing loss were less able to use shortened transition or shortened vowel centers to identify vowels as compared to their normal-hearing peers. Whole syllable and initial transition yielded better identification performance than the vowel center for /ɑ/, but not for /i/ or /u/. CONCLUSIONS: The children with hearing loss may require a longer time window than children with normal hearing to integrate vowel cues over time because of altered peripheral encoding in spectrotemporal domains. Clinical implications include cognizance of the importance of vowel perception when developing habilitative programs for children with hearing loss.

Autonomic dysfunction: A guide for FPs.

Impotence, bladder dysfunction, GI symptoms, and orthostatic hypotension can signal autonomic dysfunction. Here's what you'll see and how to respond.

Infectious endocarditis: diagnosis and treatment.

Infectious endocarditis results from bacterial or fungal infection of the endocardial surface of the heart and is associated with significant morbidity and mortality. Risk factors include the presence of a prosthetic heart valve, structural or congenital heart disease, intravenous drug use, and a recent history of invasive procedures. Endocarditis should be suspected in patients with unexplained fevers, night sweats, or signs of systemic illness. Diagnosis is made using the Duke criteria, which include clinical, laboratory, and echocardiographic findings. Antibiotic treatment of infectious endocarditis depends on whether the involved valve is native or prosthetic, as well as the causative microorganism and its antibiotic susceptibilities. Common blood culture isolates include Staphylococcus aureus, viridans Streptococcus, enterococci, and coagulase-negative staphylococci. Valvular structural and functional integrity may be adversely affected in infectious endocarditis, and surgical consultation is warranted in patients with aggressive or persistent infections, emboli, and valvular compromise or rupture. After completion of antibiotic therapy, patients should be educated about the importance of daily dental hygiene, regular visits to the dentist, and the need for antibiotic prophylaxis before certain procedures.