A current idea about the persistence of tinnitus is that fixation of this phantom auditory perception in the central auditory system may be influenced by attention to it. The present study investigated the mechanisms of involuntary attention and analysed performance in categorising sounds in tinnitus, simulated-tinnitus and control subjects. The sounds were presented in one ear and were preceded by presentation of frequent and deviant stimuli in the other ear. The results showed classical attention capture by deviant stimuli. In addition, the unilateral tinnitus subjects responded more accurately in the tinnitus ear than in the non-tinnitus ear. In contrast, the 'simulated-tinnitus' group showed no difference in the results between the ear where the tinnitus simulation was presented and the opposite ear. These findings suggest a difficulty in attention directing when the attention location coincides with the tinnitus ear and provides evidence for an attention focus on the tinnitus ear.

Most patients with tinnitus are neither depressed nor seriously bothered by their tinnitus. Patients who complain bitterly of tinnitus, however, are often found to have a MDD. Treatment with tricyclic antidepressant drugs helps these patients, especially those who complain of insomnia. Other types of drugs and psychotherapy may also be helpful.

The gamma band response (GBR) is an exogenous, cortically generated, event-related potential that occurs between 20- and 170-msec post-stimulus onset. The auditory GBR is superimposed on the transient evoked middle and long latency cortical auditory evoked potentials and demonstrates a peak spectral frequency between 30 and 40 Hz. The present investigations were conducted to evaluate the test-retest stability and short-term habituation of the GBR. Both the GBR and N1 were recorded from six normal-hearing, neurologically intact subjects (Investigation 1, test-retest stability) and two subjects with intractable epilepsy with implanted subdural electrode grid arrays (Investigation 2, short-term habituation characteristics). For Investigation 1, the test-retest interval was 1 month. For Investigation 2, 300 samples were acquired per stimulus block (a 10-minute interval) and then subaveraged in blocks of 25 to 50 samples each. Results suggest that (1) like N1, the GBR shows high repeatability (qualitative) and test-retest stability (quantitative) and (2) the GBR does not demonstrate evidence of short-term habituation.

The purposes of these investigations were to (1) evaluate tinnitus loudness measures of unskilled normal listeners asked to imagine that they are experiencing a constant monaural tonal tinnitus and (2) compare the performance of these listeners to that of a sample of patients with tinnitus. Subgroups of 24 patients participated in two investigations. Results suggest that (1) normal subjects asked to imagine a high-pitched, tonal tinnitus show significantly greater tinnitus loudness matching levels (a) when they do not have an external reference,(b) after a 1-week interval, and (c) for low-frequency matching tones;(2) patients with high-pitched tinnitus did not demonstrate statistically significant differences in tinnitus loudness judgments within or between sessions or frequencies;(3) tinnitus patients do not differ significantly from normals feigning tinnitus in the variability of tinnitus loudness matching levels within a single session (two measures) or after a 1-week interval (one measure); and (4) normals feigning tinnitus tended to choose significantly greater loudness matching levels than did tinnitus subjects.

The Three-Clinic Hearing Aid Selection Profile (HASP) was developed to assess a patient's beliefs about a number of basic considerations felt to be critical to the hearing aid selection (HAS) process. These characteristics are felt to be key to the acceptance of amplification and include motivation, expectations, cost of goods and services, appearance (cosmesis), attitudes about technology, physical function/limitations, communication needs, and lifestyle. The results of the first investigation suggest that we have been successful in developing a 40-item metric with adequate internal consistency reliability that assesses the aforementioned characteristics. Second, results of the administration of this tool to a large group of individuals indicated that (1) age impacted scores on the Technology, Physical Function, and Communicative Needs subscales;(2) gender impacted scores on the Motivation, Expectation, Technology, Communicative Needs, and Appearance subscales;(3) previous hearing aid use affected scores on the Motivation subscale;(4) level of education impacted scores on the Physical Function and Lifestyle subscales; and (5) self-perceived hearing handicap had an effect on Motivation and Communicative Needs subscale scores. Percentile data collected from this subject sample are presented as a benchmark against which to evaluate responses from individual patients. Case studies are presented to illustrate the potential clinical utility of this device.

Acquired bilateral vestibular impairment can be a devastating disorder that is most frequently the result of aminoglycoside-induced toxicity. The presenting complaints are typically oscillopsia and gait and balance disturbances. These patients can be excellent candidates for vestibular rehabilitation therapy that focuses on facilitating maximal use of any remaining vestibular function, improving gaze and postural stability through the use of visual and somatosensory cues, and improving home and workplace safety. The prognosis for recovery is determined by the extent of the loss and the presence of other progressive disorders that may affect vision or somatosensation, coexisting illnesses, and the patient's compliance with the therapy program. Two cases are presented to illustrate the salient aspects of vestibular rehabilitation for patients with acquired bilateral vestibular system loss, including factors affecting patient progress and final outcome.

The purpose of this report was to characterize the self-perceived balance disability/handicap of patients with bilateral reductions and bilateral complete losses of peripheral vestibular system function. Data from 72 patients whose electronystagmography and rotational examinations suggested normal, unilateral, or bilateral reductions in peripheral vestibular system function were used in the first investigation. Patients also completed a Dizziness Handicap Inventory (DHI). Results demonstrated significant group differences for DHI total and physical subscale scores. There were significant differences between normal and bilateral weakness groups for the total DHI score and between normal and unilateral and normal and bilateral weakness groups for the physical subscale score. In a second investigation, an item analysis of the DHI is presented for five patients with bilateral complete losses of peripheral vestibular system function. Results show that, predictably, these patients have difficulty engaging in activities requiring an intact vestibulocular reflex (e.g., physical activities such as sports, household chores).

OBJECTIVE: This study aimed to develop a screening version of the Dizziness Handicap Inventory (DHI). STUDY DESIGN: Three separate prospective investigations are reported that assess: 1) the equivalency of the screening version of DHI (DHI-S) for the DHI; 2) the test-retest reliability of the DHI-S; and 3) whether abnormal performance on balance function testing is associated with greater scores on the DHI-S. SETTING: The investigation was conducted in the Balance Function Laboratory of the Division of Audiology at Henry Ford Hospital, which is a tertiary care setting. PATIENTS: There were 281 consecutive patients (for investigations 1 and 2) and 45 consecutive patients (for investigation 3) seen for balance function testing. INTERVENTIONS: There was a 1-week interval between test and retest administrations of the DHI-S. MAIN OUTCOME MEASURES: Comparability of the DHI-S for the DHI and the test-retest reliability of the DHI-S were assessed with a Pearson Product-Moment correlation coefficient. Scores on the DHI-S for patients with and without abnormal balance function tests were assessed with an analysis of variance. RESULTS: Results showed that scores on the DHI-S had high comparability for the total score on the DHI (r=0.86). The short-term, test-retest reliability for the DHI was high (r=0.95). Abnormal performance on the sensory organization subtest of computerized dynamic posturography was associated with significantly greater scores on the DHI-S. CONCLUSIONS: Results support the contention that DHI-S is a psychometrically robust screening measure of self-perceived dizziness disability-handicap.

Previous studies have shown that the dorsal cochlear nucleus exhibits increased spontaneous activity after exposure to intense sound. Such increases were apparent 1-2 months after the exposure and were generally proportional to the shift in response thresholds induced by the same exposure. The purpose of the present study was to determine whether this sound-induced increase in spontaneous activity is an early event which can be observed shortly after exposure. As in previous studies, anesthetized hamsters ranging in postnatal age from 60-70 days were exposed to a 10-kHz tone at levels between 125 and 130 dB SPL for a period of 4 h. Control animals were similarly anesthetized but were not exposed to the intense tone. Exposed animals were examined in two groups, one at 30 days after exposure, the other at 2 days after exposure. Time of exposure was adjusted so that all animals were between 90 and 100 days of age when spontaneous activity was studied electrophysiologically. The results showed that the increases in spontaneous activity, which were evident at 30 days after exposure, were not observed in animals studied 2 days after exposure. This result contrasted with the effect of the intense tone exposure on neural response thresholds. That is, the shifts in response thresholds seen 2 days after exposure were similar to those observed in animals studied 30 days after exposure. These results indicate that changes in spontaneous activity reflect a more slowly developing phenomenon and occur secondarily after induction of threshold shift.

BACKGROUND: While gallstones are associated with cancers of the gallbladder, the actual nature of their relationship needs to be clarified. This would aid the recommendations on the need for prophylactic cholecystectomy. METHODS: A systematic search of the scientific literature was carried out using the Medline, the Embase, and the Cochrane Central Register of Controlled Trials for the years 1891-2009 to obtain access to all publications involving gallstones in gallbladder cancer. RESULTS: While some epidemiological evidence supports a causal relationship for gallstones in gallbladder cancer, other studies have demonstrated a relatively low incidence of gallbladder cancer in countries reporting a high incidence of gallstones as a whole. In those studies where gallstones appear to have a causative role for cancer, the risk increases with increasing size, volume and weight, and number of the stones. The impact of duration of the stone or its composition is not clear. Experimental evidence from studies examining the impact of artificially introducing gallstones in the gallbladder has failed to lead to carcinogenesis. CONCLUSIONS: The evidence at the current time indicates that gallstones are a cofactor in the causation of gallbladder cancer. Absolute proof of their role as a cause for gallbladder cancer is lacking. The recommendation for prophylactic cholecystectomy in countries reporting a high incidence of gallbladder cancer and associated gallstones needs to be tailored to the epidemiological profile of the place.

Although many studies examine the biological phenomena that mediate the relationship between stress and illness, more research is needed regarding psychological variables that may mediate this relationship. Thus, the current study investigates the mediating effects of locus of control and self-efficacy in the relationships among stress, illness, and the utilization of health services in a sample of 159 college students. Results suggest that participants who endorse higher levels of stress also endorse higher levels of illness, higher levels of external locus of control, and lower levels of self-efficacy. In addition, structural equation modeling suggests that there are direct relationships between stress and illness and between illness and the utilization of health services. Further, locus of control appears to be a partial mediator in the relationship between stress and illness. Given the link established between stress and illness and the individual differences associated with reactions to stressful situations, it is important for future examinations to continue to identify potential mediators of the stress-illness link.

The purpose of the present study was to analyze sex and regional differences in the suicide rate of adolescents and the methods they used for suicide in Italy during the period 1970-2002. Temporal trends and regional variations in suicide for Italian adolescents were retrieved from the Italian database on mortality for the period 1970-2002, collected by the Italian Census Bureau and processed by the Italian National Institute of Health-Statistics Unit. In the period 1970-2002, 3,069 adolescent suicides were monitored in Italy. Analyses of these suicides identified significant differences by region of residence and sex. Males were 2.1 times more likely than females to kill themselves. Male and female suicides had inverse trends in the years analyzed, so that the sex difference at the present time is the result of a continuous increase in male suicides and a decrease in female suicides since 1970. The dramatic peaks observed over the time period studied cannot be attributed to a single cause, indicating that further studies are needed to better understand the phenomenon.

The objective of this investigation was to describe the detection of foot and mouth disease (FMD) outbreaks in nonendemic areas, and to consider how events early in an epidemic influence the epidemic's course. We identified 24 epidemics that occurred between 1992 and 2003 in areas officially considered free of FMD. We obtained information about these epidemics from many sources, including the scientific literature, the grey (non peer-reviewed) literature, and individuals involved with the outbreaks. While most of the epidemics consisted of fewer than 150 infected premises, there were 4 extremely large epidemics, each consisting of more than 2000 infected premises. There was no direct relationship between the time to detection and either the total number of infected premises or the number of animals killed for disease control purposes. We believe that the movement of infected animals through markets was the most critical factor that contributed to the unusual magnitude of the very large epidemics.

We present a framework for the rational analysis of elemental causal induction-learning about the existence of a relationship between a single cause and effect-based upon causal graphical models. This framework makes precise the distinction between causal structure and causal strength: the difference between asking whether a causal relationship exists and asking how strong that causal relationship might be. We show that two leading rational models of elemental causal induction, DeltaP and causal power, both estimate causal strength, and we introduce a new rational model, causal support, that assesses causal structure. Causal support predicts several key phenomena of causal induction that cannot be accounted for by other rational models, which we explore through a series of experiments. These phenomena include the complex interaction between DeltaP and the base-rate probability of the effect in the absence of the cause, sample size effects, inferences from incomplete contingency tables, and causal learning from rates. Causal support also provides a better account of a number of existing datasets than either DeltaP or causal power.

The relationship between occlusal overload and peri-implant bone loss remains a controversial topic in implant dentistry. A causal relationship between the incidence of marginal bone loss next to an implant and occlusal overload implies a treatment plan and occlusal scheme would benefit from a force management approach. A MEDLINE-assisted and hand search of peer-reviewed English literature and relative textbooks were used for a selective review of articles addressing biomechanical stress and bone loss in cellular biomechanics, engineering principles, mechanical properties of bone, animal studies, clinical reports, bone physiology, and implant design biomechanics. These papers demonstrate occlusal overload on implants may increase the incidence of marginal bone loss.

There is currently considerable controversy regarding a proposed causal relationship between the use of isotretinoin and depression and suicide. A search was made of the MEDLINE, EMBASE and PsychINFO databases using the search terms 'isotretinoin','depression' and 'suicide'. Despite numerous case reports linking isotretinoin to depression, suicidal ideation and suicide, there is, as yet, no clear proof of an association. While isotretinoin, used to treat acne vulgaris, has not been demonstrated to be associated with depression or suicide, the possibility of a relatively rare idiosyncratic adverse effect remains. GPs have a role in the clinical application of these findings.

We report a girl with congenital nephrotic syndrome (CNS) associated with cytomegalovirus (CMV) infection and histological findings on renal biopsy that suggested a causal relationship between the two. She was subsequently found to be homozygous for a nonsense mutation in the NPHS2 gene encoding podocin (R138X), which is the true cause of her NS. Based on review of the literature and our findings in this patient, we propose that the clinical entity known as CMV causing CNS may not exist.

OBJECTIVE: To evaluate the use of levodopa therapy in patients with Parkinson's disease and malignant melanoma. DATA SOURCES: A MEDLINE search (January 1966-September 1999) of English-language articles was conducted. Key search terms included levodopa, melanoma, and Parkinson's disease; 34 case reports were identified. DATA SYNTHESIS: Carbidopa/levodopa continues to be a mainstay in the treatment of Parkinson's disease. Since the late 1970s, a warning has appeared in the prescribing literature for levodopa regarding the risk of activating malignant melanoma. An evaluation was conducted of the case reports in which a causal relationship between levodopa and melanoma was suggested. CONCLUSIONS: There is an unlikely association between levodopa and induction or exacerbation of malignant melanoma.

The chemical resolution, using N-tosyl-L-proline as a chiral auxiliary, of a racemate of the pyrazole analog (+/-)-N-Boc-CPzI of the left hand segment (CPI) of the antitumor agent CC-1065, and the cytotoxic evaluation of both enantiomers are described. The reported results further validate the direct relationship between chemical solvolytic stability of the cyclopropane ring and cytotoxicity proposed by Boger and coworkers.