Biomedical subjects

S Barz

Publications and source records attributed to S Barz.

4 recordsLinked to original sources

PubMed1998

Chemosensory event-related potentials change with age.

The study examined age-related changes in the perception of olfactory and trigeminal chemical stimuli using chemosensory event-related potentials (CSERP). Three groups of healthy volunteers, each comprised of 8 men and 8 women, were tested (age ranges 15-34, 35-54, and 55-74 years). Subjects underwent extensive psychological testing focusing on impairments of memory and attention. In addition, odor identification and discrimination ability was evaluated, as well as detection threshold sensitivity for two odorants. Odor discrimination scores exhibited a significant age-related decrease. Significant age-related changes were also observed for CSERP N1P2 and P2 amplitudes, and for the N1 peak latency. The age-related decrease of CSERP amplitudes appeared to follow a different time course for responses to trigeminal and olfactory stimulants.

Adolescent↗

PubMed1997

Chemosensory event-related potentials in response to trigeminal and olfactory stimulation in idiopathic Parkinson's disease.

Decrease of olfactory function in patients with Parkinson's disease (PD) has been reported by several authors. The current study investigated olfaction in PD patients using olfactory event-related potentials (OERPs) as an electrophysiologic correlate of olfactory function in combination with psychophysical testing. A specific focus was the influence of antiparkinsonian drugs. We investigated PD patients treated with antiparkinsonian drugs (n = 13) and PD patients who received no pharmacologic treatment (n = 18). They were compared to age- and sex-matched control subjects (n = 38). To obtain OERPs, stimulants were chosen to stimulate specifically the olfactory nerve (2.1 ppm vanillin, 0.8 ppm H2S). In addition, chemosomatosensory event-related potentials were recorded after trigeminal stimulation with 52% v/v CO2. Moreover, the subjects' ability to identify and to discriminate odorants was tested by means of a "squeeze bottle" technique. The study yielded the following major results: (1) Odor identification was impaired in PD patients. It was not influenced by treatment with antiparkinsonian drugs. (2) The OERP latencies were prolonged in both PD patients taking and not taking antiparkinsonian drugs; however, this effect was more pronounced in PD patients taking antiparkinsonian drugs. (3) The intranasal chemosensory trigeminal system seemingly was neither affected by the neuronal degeneration seen in PD nor by treatment with antiparkinsonian drugs.

Adult↗

PubMed1996

Loss of olfactory function leads to a decrease of trigeminal sensitivity.

Healthy controls were compared to patients with decreased olfactory sensitivity (n = 32) to investigate interactions between the olfactory and trigeminal systems. Amplitudes of chemo-somatosensory event-related potentials in response to suprathreshold trigeminal stimuli (CO2) were found to be smaller in patients (P < 0.05) indicating a decrease of trigeminally mediated sensations.

Action Potentials↗

PubMed1996

"Sniffin' sticks": screening of olfactory performance.

"Sniffin' Sticks" is a new test of nasal chemosensory performance based on pen-like odour-dispensing devices. This portable test is suited for repetitive, inexpensive screening of odour identification. The test includes a forced odour-identification task for seven odours performed by means of a list of four items (multiple-choice). In 146 subjects the basic screening test was compared to a down-scaled version of the UPSIT (CC-SIT). Sniffin' Sticks exhibited a relatively higher coefficient of correlation with the subjects' age; they also demonstrated the women's superior olfactory sensitivity more pronounced when compared to men. In addition, the coefficient of correlation between age and olfactory performance was slightly higher when the sticks were used. Preliminary investigations in nine patients with impaired olfactory function (i.e., anosmic or hyposmic patients) revealed significantly lower scores in patients compared to healthy controls matched for age and sex (p < 0.001). It is concluded that Sniffin' Sticks may be useful in the routine clinical assessment of olfactory performance where both time and costs matter.

Adult↗