Sex difference in counts of α4 and α7 nicotinic acetylcholine receptors in the nasal polyps of adults with or without exposure to tobacco smoke.

OBJECTIVE: To assess counts of α4 and α7 nicotinic acetylcholine receptors in nasal polyps of adults with or without long-term exposure to cigarette tobacco smoke. METHODS: Twenty-two patients with and 22 patients without exposure to cigarette tobacco smoke participated in the study. After endoscopic polypectomy, the fragments of the nasal polyps were analysed by immunohistochemistry. RESULTS: Compared to patients with no exposure, patients with exposure showed higher counts of α4 and α7 nicotinic acetylcholine receptors (t-test, p 0.05). CONCLUSION: Exposure to cigarette tobacco smoke may induce increased counts of α4 and α7 nicotinic acetylcholine receptors in nasal polyps of adults, with lower counts in males than females without exposure to tobacco smoke.

Utricular hypofunction in patients with type 2 diabetes mellitus.

The aim of this study was to assess the function of the utricle and horizontal semicircular canals in patients with type 2 diabetes mellitus receiving primary health care, with/without a history of falls. 101 patients with type 2 diabetes mellitus, 34 to 84 years old (26 with and 75 without a history of falls) and 51 healthy volunteers (40-83 years old) accepted to participate. They denied having a history of dizziness, vertigo, unsteadiness, hearing loss, or neurological disorders. None of them were seeking care due to sensory or balance decline. After a clinical evaluation and report of symptoms related to balance using a standardised questionnaire, lateral canal function was assessed by sinusoidal rotation at 0.16 Hz and 1.28 Hz (60°/sec peak velocity), otolith function was assessed by static visual vertical (average of 10 trials) and dynamic visual vertical during unilateral centrifugation (300°/sec at 3.5 cm) and static posturography was performed on hard/ soft surface with eyes open/closed. Compared to healthy volunteers, patients showed decreased responses to unilateral centrifugation, but similar responses to horizontal canal stimuli (independently of age, peripheral neuropathy or a history of falls) (ANCoVA p < 0.05) and a larger sway area with a lengthier sway path. Compared to patients with no falls, patients with falls had a higher female/male ratio and a higher frequency of score ≥ 4 on the questionnaire of symptoms related to balance, but similar age, body mass index and frequency of peripheral neuropathy. In patients with type 2 diabetes mellitus, receiving primary healthcare who are not seeking care due to sensory or balance decline, utricular function may be impaired even in the absence of horizontal canal dysfunction or a history of falls.

Quality of life of young patients with recurrent respiratory papillomatosis.

OBJECTIVE: To assess quality of life of children and teenagers with recurrent respiratory papillomatosis, according to the evidence of infection by human papillomavirus types 6 and 11, compared with healthy volunteers and patients with chronic otitis media. METHOD: Participants and their parents completed the Pediatric Quality of Life Inventory 4.0. RESULTS: Patients with recurrent respiratory papillomatosis and their parents reported lower quality of life than healthy subjects (p < 0.01), but similar quality of life to patients with chronic otitis media. Those with human papillomavirus type 11 showed the lowest scores among all participants (p < 0.05). CONCLUSION: Young Mexican patients with recurrent respiratory papillomatosis and their parents perceive a poor quality of life, and they may experience limitations in interactions with their peers. Infection by human papillomavirus type 11 may increase the impact of the disease on quality of life.

Derealization during utricular stimulation.

BACKGROUND: Feelings of unreality have been provoked in healthy subjects undergoing stimulation of the semicircular canals, but no studies have assessed the influence of otoliths stimulation on depersonalization/derealization (DD) symptoms. OBJECTIVE: To assess DD symptoms during unilateral centrifugation in healthy adults. METHODS: 100 subjects participated in the study. They completed a standardized questionnaire of symptoms related to balance (Jáuregui-Renaud 2003), the 17-item Hamilton Depression Rating Scale, the Zung Instrument for Anxiety Disorders and the Cox & Swinson 28-item DD inventory. After unilateral centrifugation (300°/s at 3.5 cm), subjects completed the DD inventory again. RESULTS: Centrifugation provoked symptoms which subjects denied ever experiencing before. The items most frequently reported were "Body feels strange or different in some way" (56%) and "Time seems to pass very slowly" (55%). The DD total score was related to the score of symptoms related to balance and to the depression inventory with no influence from the general characteristics of the subjects or the responses to vestibular tests. The individual scores of symptoms of vestibular function and derealization were related to the report of the other DD symptoms. CONCLUSIONS: In healthy subjects, unilateral centrifugation provokes DD symptoms. The results support that distorted vestibular signals may create a misleading frame of reference which mismatch with the other senses, giving rise to 'unreal' perceptions.

Influence of exposure to tobacco cigarette smoke on the eosinophil count in the nasal mucosa of young patients with perennial allergic rhinitis.

BACKGROUND: To assess the influence of exposure to tobacco cigarette smoke on the eosinophil count and the frequency of apoptosis of eosinophils in the nasal mucosa of teenagers with perennial allergic rhinitis. METHODS: Fifty patients were evaluated (aged 10 to 19 years old): 25 patients with and 25 patients with no recent exposure to tobacco cigarette smoke, by means of The Global Youth Tobacco Survey and cotinine/creatinine ratio. After a clinical evaluation, all the patients replied to a validated questionnaire of the severity of nasal symptoms; then, a nasal sample was processed to identify the eosinophil count and the frequency of apoptosis of eosinophils. RESULTS: Patients with active exposure to tobacco cigarette smoke had higher eosinophil counts than patients with no exposure to the smoke. In the two groups, apoptosis of eosinophils in the nasal mucosa was scarce and no significant correlation was observed between the frequency/severity of the nasal symptoms and the eosinophil count. CONCLUSION: Teenagers with perennial allergic rhinitis and active exposure to tobacco cigarette smoke may show increased eosinophil counts in the nasal mucosa, which might not be related to apoptosis of eosinophils or to the frequency/severity of nasal symptoms.

Rhinomanometry in young patients with perennial allergic rhinitis with/without recent exposure to tobacco smoke.

OBJECTIVE: To assess the influence of environmental exposure to tobacco smoke on the nasal symptoms and nasal resistance of young patients with perennial allergic rhinitis. DESIGN: Cross-sectional study. SETTING: Tertiary referral centre. PARTICIPANTS: Fifty patients were evaluated (aged 10-19 years old): 25 patients with and 25 patients without recent exposure to tobacco smoke (confirmed by cotinine/creatinine ratio). MAIN OUTCOMES MEASURES: After a clinical evaluation, all the patients replied to a validated questionnaire of the severity of the nasal symptoms. Then total nasal airway resistance was recorded by active anterior rhinomanometry. RESULTS: Patients with exposure to tobacco smoke had a larger total resistance than patients without exposure (t-test, P < 0.01). No significant correlation was observed between the total score of the questionnaire of nasal symptoms and the nasal resistance. CONCLUSIONS: In young patients with perennial allergic rhinitis, exposure to tobacco smoke can be related to increased nasal resistance, which may not be recognised by the report of nasal symptoms.

Early auditory middle latency evoked potentials correlates with recovery from aphasia after stroke.

OBJECTIVE: To assess the relationship between the latency of Pa and Nb peaks of the middle latency auditory responses and the score on the Boston Diagnostic Aphasia Examination, during a 6-month follow-up after stroke in the territory of the left mid cerebral artery. METHODS: The middle latency auditory potentials of 10 aphasic stroke patients were recorded within the first 3 days post-onset, at the time of hospital discharge and 2, 4 and 6 months afterwards, along with that of 30 control subjects; in patients, the evolution of aphasia was evaluated using the Boston Diagnostic Aphasia Examination score. RESULTS: During follow-up decreasing potential latencies and increasing language scores were observed (ANCOVA, R(2) 0.75, p<0.01); the Nb peak latency recorded during the first days after stroke was related to the language score difference after 6 months (Pearson, r=0.66, p<0.01). CONCLUSIONS: In patients with aphasia after stroke, the auditory electrical response recorded at hospital discharge, after stroke is related to their recovery from aphasia, evaluated by the Boston Diagnostic Aphasia Examination. SIGNIFICANCE: Early middle latency auditory evoked responses may have a prognostic value in aphasic stroke patients.

Depersonalisation/derealisation symptoms and updating orientation in patients with vestibular disease.

BACKGROUND: Patients with vestibular disease have an increased rate of reporting symptoms of depersonalisation/derealisation (DD) and similar symptoms can be provoked in healthy subjects during caloric vestibular stimulation. OBJECTIVE: To assess the relationship between DD symptoms in patients with peripheral vestibular disease and their ability to update orientation in the environment. METHODS: Sixty healthy subjects and 50 patients with peripheral vestibular disease completed a DD questionnaire (Cox and Swinson, 2002) and a General Health Questionnaire (GHQ)-12 (Goldberg and Williams, 1988). This was followed by a test of updating spatial orientation in which subjects were exposed to 10 manually driven whole body rotations of 45 degrees, 90 degrees or 135 degrees in a square room, which contained distinctive features on the walls, in such a way that the features and corners subtended 45 degrees with respect to the subject. After each rotation subjects reported which wall or corner they were facing. Estimation error was calculated by subtracting the reported rotation from the actual rotation. RESULTS: DD scores were significantly higher in vestibular patients than in healthy subjects (p<0.05, t test). In patients, the lowest symptom scores and the lowest estimation errors were found in those with a unilateral canal paresis without balance symptoms whereas the highest scores and largest estimation errors were found in those with bilateral vestibular loss (p<0.05, ANOVA). Across all patients, DD scores were related to estimation errors (adjusted r2 = 0.25, p<0.05, ANCOVA). CONCLUSIONS: Patients with peripheral vestibular disease have a deficit in the ability to update orientation on the environment and a high prevalence of DD symptoms, which may imply a high order effect of the vestibular impairment. Derealisation symptoms in vestibular disease may be a consequence of a sensory mismatch between disordered vestibular input and other sensory signals of orientation.

Systemic high blood pressure and inner ear dysfunction: a preliminary study.

OBJECTIVE: To assess the association between inner ear dysfunction and retinal vascular changes related to systemic arterial hypertension. DESIGN: A comparative, cross-sectional and observational study. SETTING: Primary care. MAIN OUTCOMES MEASURES: Hearing and vestibular symptoms evaluated by a standardized questionnaire; cochlear function evaluated by audiometry and distortion product otoacoustic emissions; vestibular function evaluated by oculomotor and bithermal caloric tests and vascular retinal compromise evaluated by ophthalmoscopy (according to the modified Scheie classification). RESULTS: Forty-two subjects participated in the study, 21 with and 21 without arterial hypertension, age and sex matched; with no history of diabetes mellitus and with normal glucose levels and normal blood lipids. Although patients with hypertension reported vertigo more frequently than control subjects, conventional oculomotor and bithermal caloric tests showed no difference between the two groups. Patients with hypertension showed deterioration of hearing thresholds at 8 kHz and, compared with normotensive subjects, a higher frequency of abnormal otoacoustic emissions (P = 0.01). According to Scheie classification, 43% (95% CI: 33-53%) of the patients showed second degree retinal vascular compromise and 24% (95% CI: 15-33%) of them showed first degree compromise. The degree of the vascular retinal compromise was significantly correlated with the hearing thresholds at 8 kHz (Spearman's correlation coefficient 0.45, P = 0.002) and it was also consistent with the absence of otoacoustic emissions at frequencies between 4 and 8 kHz. CONCLUSION: The results of this preliminary study suggest that patients with systemic arterial hypertension may have cochlear dysfunction associated with the vascular disease because of hypertension, which could be silent and without clear evidence of vestibular dysfunction.

[Meningeal herniation associated to chronic otitis media in an otology center in the City of Mexico]. / La hernia de meninges asociada a otitis media crónica en un centro de atención otológica de la ciudad de México.

To assess the frequency and clinical characteristics of meningocele and meningoencephalocele into the middle ear, at an otological referral center of Mexico city. After analyzing 586 recordings of middle ear surgery, we identified that 3 (0.5%) had defects of the tegmen timpani, 2 had brain abscesses (0.34%) and 1 had (0.17%) a facial palsy. Two of the patients with defects of the tegmen timpani had herniation of the intracraneal tissue. Case 1. A 38 year old woman with a history of bilateral chronic otitis media, with 2 surgeries in the left ear. She was seeking medical care because of right hearing loss. However, computed tomography and magnetic resonance showed a defect of the tegmen timpani with temporal lobe herniation in the left ear. Case 2 was a 46 year old woman with no history of ear disease, just high blood pressure. She was seeking medical care because of right hearing loss, vertigo and headache. The clinical evaluation suggested tissue in the middle ear and the computed tomography showed a defect of the tegmen timpani, meningocele was confirmed by surgery. In the 2 patients the clinical characteristics did not suggest herniation of intracraneal tissue as the first diagnosis. This show us the importance of an intended evaluation and image studies to make an early diagnosis.

Depersonalisation/derealisation symptoms in vestibular disease.

BACKGROUND: Depersonalisation is a subjective experience of unreality and detachment from the self often accompanied by derealisation; the experience of the external world appearing to be strange or unreal. Feelings of unreality can be evoked by disorienting vestibular stimulation. OBJECTIVE: To identify the prevalence of depersonalisation/derealisation symptoms in patients with peripheral vestibular disease and experimentally to induce these symptoms by vestibular stimulation. METHODS: 121 healthy subjects and 50 patients with peripheral vestibular disease participated in the study. For comparison with the patients a subgroup of 50 age matched healthy subjects was delineated. All completed (1) an in-house health screening questionnaire; (2) the General Health Questionnaire (GHQ-12); (3) the 28-item depersonalisation/derealisation inventory of Cox and Swinson (2002). Experimental verification of "vestibular induced" depersonalisation/derealisation was assessed in 20 patients and 20 controls during caloric irrigation of the labyrinths. RESULTS: The frequency and severity of symptoms in vestibular patients was significantly higher than in controls. In controls the most common experiences were of "déjà vu" and "difficulty in concentrating/attending". In contrast, apart from dizziness, patients most frequently reported derealisation symptoms of "feel as if walking on shifting ground", "body feels strange/not being in control of self", and "feel 'spacey' or 'spaced out'". Items permitted discrimination between healthy subjects and vestibular patients in 92% of the cases. Apart from dizziness, caloric stimulation induced depersonalisation/derealisation symptoms which healthy subjects denied ever experiencing before, while patients reported that the symptoms were similar to those encountered during their disease. CONCLUSIONS: Depersonalisation/derealisation symptoms are both different in quality and more frequent under conditions of non-physiological vestibular stimulation. In vestibular disease, frequent experiences of derealisation may occur because distorted vestibular signals mismatch with the other sensory input to create an incoherent frame of spatial reference which makes the patient feel he or she is detached or separated from the world.

Cerebral blood flow during supine rest and the first minute of head-up tilt in patients with orthostatic intolerance.

AIM: To assess the cerebral blood flow velocity during the first minute of head-up tilt in patients with postural tachycardia syndrome (POTS) or neurally-mediated reflex syncope compared with patients with dizziness. METHODS: We evaluated 120 patients selected from 470 patients who underwent head-up tilt testing: 40 with POTS, 40 with typical neurally-mediated reflex syncope and 40 who complained of dizziness with no history of loss of consciousness and a negative head-up tilt test (with and without isosorbide). Transcranial Doppler sonography of the middle cerebral artery, heart rate and brachial blood pressure were recorded during a 70 degrees head-up tilt test. RESULTS: During both baseline in supine position and the first minute of upright tilt, patients with postural tachycardia syndrome showed higher heart rate and cerebral blood flow velocity than patients with dizziness and patients with neurally-mediated reflex syncope (P < 0.05, ANOVA), but no significant difference was observed on the Gosling's pulsatility index. CONCLUSION: Patients with POTS have an autonomic dysfunction that is not triggered by upright posture but is accentuated by it.

Influence of acute unilateral vestibular lesions on the respiratory rhythm after active change of posture in human subjects.

The influence of acute unilateral vestibular lesions on respiratory rhythm after active change of posture, was evaluated by comparing responses from patients with acute vestibular neuritis, with those from normal subjects with minor injuries other than vestibular (e.g. epistaxis, headache) and patients with chronic bilateral vestibular dysfunction. Respiratory movements of the thorax-abdomen were recorded during 5 minutes in supine position, 5 minutes of back-unsupported sitting and 5 minutes of upright stance. Compared to supine position, sitting-up induced different responses in each group (p < 0.05, ANOVA). The healthy subjects showed a consistent decrease in the mean respiratory frequency related to an increase of the expiration time, which was absent in patients with vestibular neuritis. Subjects with minor injuries showed the opposite changes of expiration time and inspiration time with no change of the respiratory frequency and patients with bilateral vestibular dysfunction showed a trend to increase their respiratory frequency. Standing-up did not evoke any further changes in any group. We conclude that the vestibular system modulates the respiratory response to reorientation of the head and trunk to upright position and this influence is reduced during the acute stage of a vestibular lesion.

Vestibular influence on the cardiorespiratory responses to whole-body oscillation after standing.

We assessed the influence of vestibular stimulation by whole-body oscillation in the yaw plane on the cardiorespiratory responses after a change of posture from sitting to standing. Eighteen healthy subjects (21-70 years old) and six patients with bilateral vestibular loss (46-59 years old) were tested. For comparison, a subgroup, age matched to the patients, was created from the healthy group. After a 10-min rest, subjects who were sitting, back unsupported, stood on a platform affording en bloc head and body support. The platform was either static or oscillated at 0.1 Hz and 0.5 Hz (20 degrees amplitude) for 2 min. Presentation of the three conditions was counterbalanced. Respiration, ECG, blood pressure and head position were recorded. During oscillation at 0.5 Hz, the respiratory responses were different between groups; healthy subjects showed a significant increase of the respiratory frequency (1.75+/-2.1 breaths/min), which was not observed in the patients (0.16+/-0.7 breaths/min) ( p<0.05, ANOVA). Absolute changes of heart rate and blood pressure were similar for the three conditions in all the subjects. However, healthy subjects showed a decrease of power spectrum density of the high-frequency ('respiratory') component of heart rate variability on standing during all three conditions. This response was variable among the patients and the age-matched group. The study shows that semicircular canal activation influences the respiratory rhythm during movements in the yaw plane in standing subjects. In addition, we observed that changes of the respiratory influence on heart rate variability during orthostatic stress are not affected by yaw oscillation or chronic vestibular loss, but may be affected by factors related to age.

Comparative study of cerebral blood flow between postural tachycardia and neurocardiogenic syncope, during head-up tilt test.

We assessed the cerebral blood flow velocity response to head-up tilt test in patients with typical neurocardiogenic syncope compared with patients showing postural tachycardia. Fifty patients (21 men) with history of orthostatic intolerance, younger than 50 years (mean 27 +/- 10), participated in the study. Transcranial Doppler sonography of the middle cerebral artery, heart rate and brachial blood pressure were recorded during a head-up tilt test. According to the outcome of the test, patients were categorized in two groups: neurocardiogenic syncope (29 patients) and postural tachycardia (21 patients). The clinical history of the two groups was similar. During baseline in the supine position, no differences in haemodynamic parameters were observed. From the first min of tilt, the heart rate was higher in patients with postural tachycardia than in patients with neurocardiogenic syncope. Although, during tilt, the absolute values of the cerebral blood flow parameters were similar in the two groups, throughout tilt, continuous observation of the Doppler recording in patients with postural tachycardia showed intermittent fluctuation of the blood flow velocity, with an oscillatory pattern, which were not observed in the recordings in patients with neurocardiogenic syncope. Comparison of patients with neurocardiogenic syncope, and those with postural tachycardia also showed larger variations of the pulsatility index (P < 0.05) in the postural tachycardia group. These findings support the possibility that abnormalities within the central nervous system play a pivotal role in the pathogenesis of postural tachycardia.

[Evidence of otospongiosis obtained by computerized tomography. Does it compromise the post-stapedectomy auditory gain?]. / La evidencia de otospongiosis por tomografía computada, compromete la ganancia auditiva post-estapedectomía?

To study the influence of tomographic otospongiosis/otosclerosis on the audiometric gain after stapedectomy, we evaluated 34 patients (mean age 39.9 years, S.D. 9.8) with otosclerosis and mixed hearing loss. We performed Computed Tomography (CT) with densitometry before stapedectomy and audiometry before and 4 weeks after the surgery. CT results were classified as compatible or not for otospongiosis (< 1000 UH) or for otosclerosis (> 2000 UH). According to the affected turns of the cochlea, the studies were classified in 3 groups. In 43% of the patients the CT showed otospongiosis. After stapedectomy, air conduction thresholds of the low (125-500 Hz), middle (500-2000 Hz) and high frequency bands (2000-8000 Hz) and for the air/bone gap were similar for the ears with or without otospongiosis (p > 0.05, ANOVA). However, patients with otospongiosis in all the cochlea showed the lowest audiometric gain for the high frequency band (p < 0.05 ANOVA). Evidence of otospongiosis evaluated just by CT has a low impact on the audiometric outcome after stapedectomy.

[Stability of auditory thresholds during the first 5 weeks after stapedectomy]. / Estabilidad de los umbrales de audición durante las primeras 5 semanas post-estapedectomía.

To assess repeatability of audiological test performed every week during the first month post-stapedectomy, audiometry was performed to 21 patients with otosclerosis (mean age 37.8 years, S.D. 9.29), every week, during the 2 weeks prior to stapedectomy and during the first 5 weeks and at week 12 after stapedectomy. Repeatability of the audiological test was evaluated comparing the difference between the audiological evaluations performed before the surgery and the difference between each consecutive pair of audiological evaluations after the surgery, using Bland & Altman method and ANOVA, allowing for 5% of significance. Before the surgery, audiological thresholds, using head phones, were repeatable for low (125-500 Hz), mid (500-2000 Hz) and high (2000-8000 Hz) frequencies in 95% of the patients. After the surgery, repeatability of air conduction thresholds for the low frequency band was evident from the 2nd week, for the mid frequency band was evident from the 3rd week and for the high frequency band from the 4th week. The gain observed at week 5 after surgery was similar to the gain observed at week 12. In conclusion, in this study, stable air conduction auditory thresholds were obtained during the first month after stapedectomy.

Orthostatic hypotension, 2001.

Upright posture requires rapid and effective circulatory and neurologic compensations to maintain blood pressure and consciousness. Although it has been recognized over the past 100 years or more that the act of standing may cause hypotension in patients with autonomic dysfunction, only recently several of the pathophysiologic mechanisms resulting in orthostatic intolerance have been discovered. In patients with orthostatic hypotension, failure of reflex vasoconstriction causes pooling of blood in the legs during standing. Not everyone with a postural blood pressure drop requires treatment, nor does everyone with posturally induced symptoms have orthostatic hypotension. This review will discuss current knowledge of a broad, heterogeneous group of disturbances in the autonomic nervous system, each of which is manifested by hypotension, orthostatic intolerance, and often syncope.

Repeatability of heart rate variability during simple cardiovascular reflex tests on healthy subjects.

BACKGROUND: Our purpose was to determine the repeatability, after 2 weeks, of frequency domain measures of heart rate variability (HRV) during simple cardiovascular reflex tests. METHODS: Twenty healthy volunteers aged 29.3 +/- 2.5 years were assessed twice (at weeks 0 and 2). Continuous electrocardiogram and minute-to-minute blood pressure were recorded during spontaneous and metronome-paced breathing (0.2 Hz). Under paced breathing, two tests were performed: 1) active change of posture: 5 min supine position, 5 min seated upright, and 5 min standing up, and 2) cold pressor test: the right hand was immersed in cold water (5 degrees C) for 2 min. RESULTS: Paced breathing elicited a significant increase of the high-frequency (HF) component of HRV. This effect was repeatable on 95% of the subjects. Active change of posture induced a significant increase of the heart rate with an increase of the low-frequency/high-frequency ratio of HRV. Although repeatability was better for the response to being seated upright than for the response to being standing up, it was always higher than 90%. The cold pressor test induced a significant increase of the heart rate and blood pressure, but with variable changes on the HRV measurements (either a decrease or an increase). Repeatability of responses was evident for 95-100% of the subjects. Although repeatability of HRV measurements in the same subject during the tests was higher than 95%, coefficients of repeatability reflected large differences among the subjects. CONCLUSIONS: The results suggest that it is not advisable to use isolated HRV changes to interpret the response to simple cardiovascular reflex tests in groups of healthy subjects.

Horizontal ocular vergence and the three-dimensional response to whole-body roll motion.

We evaluated the human binocular response to roll motion in the dark and during visual fixation with horizontal convergence. Six normal human subjects were exposed to manually driven, whole-body rotation about an earth-vertical, naso-occipital axis, under two conditions: (I) oscillation at 0.4 Hz (peak velocity 69+/-3.8 degree/s) in the dark, and whilst fixating an axial light-emitting diode at 48 cm ('near') and at 206 cm ('far'); (II) constant velocity rotation (56.5+/-3.1 degree/s) for 40 s, clockwise and counter-clockwise, in the dark, and sudden stops. Eye and head movements were monitored using scleral search coils. In head-fixed, angular velocity coordinates roll motion always evoked conjugate ocular torsion, with small conjugate horizontal and disconjugate vertical components. The resultant binocular eye responses were rotations about convergent axes. During oscillation with target fixation the convergence of the rotation axes was larger than that predicted by target geometry, producing disconjugate oscillations of vertical gaze about the target ('skewing'). Fast-phase eye movements were primarily resetting rotations about the same convergent rotation axes as the slow phases, but the small vertical velocity components had oscillatory, asymmetrical profiles. In response to velocity steps the slow-phase eye velocity decayed exponentially with time constants of 4.5+/-1.5 s for the torsional component and 5.8+/-1.9 s for the 'vertical vergence' component (right eye-left eye recordings). We conclude that in normal human subjects dynamic vertical canal stimulation with horizontal gaze convergence evokes rotation of the eyes about convergent axes and a small skewing of the eyes.