Objective: Preclinical studies indicate that dopaminergic transmission in the basal ganglia may be involved in processing of both pleasant and unpleasant stimuli. Given this, the aim of the present study was to assess taste responses to sweet, bitter, sour, and salty substances in patients with Parkinson's disease (PD). Methods: Rated intensity and pleasantness of filter paper discs soaked in sucrose (10-60%), quinine (0.025-0.5%), citric acid (0.25-4.0%), or sodium chloride (1.25-20%) solutions was evaluated in 30 patients with PD and in 33 healthy controls. Paper discs soaked in deionised water served as control stimuli. In addition, reactivity to 100 ml samples of chocolate and vanilla milk was assessed in both groups. Taste detection thresholds were assessed by means of electrogustometry. Sociodemographic and neuropsychiatric data, including cigarette smoking, alcohol consumption, tea and coffee drinking, depressive symptoms, and cognitive functioning were collected. Results: In general, perceived intensity, pleasantness, and identification of the sucrose, quinine, citric acid, or sodium chloride samples did not differ between the PD patients and controls. Intensity ratings of the filter papers soaked in 0.025% quinine were significantly higher in the PD patients compared with the control group. No inter-group differences were found in taste responses to chocolate and vanilla milk. Electrogustometric thresholds were significantly (p = 0.001) more sensitive in the PD patients. Conclusions: PD is not associated with any major alterations in responses to pleasant or unpleasant taste stimuli. Patients with PD may present enhanced taste acuity in terms of electrogustometric threshold.

Alcohol-related cues may induce relapse to heavy alcohol drinking and promote molecular adaptations in discrete brain regions. An exact nature of these molecular alterations is still unknown. In the present study, rats trained to self-administer ethanol were tested for cueinduced reinstatement of ethanol seeking after 30 days of abstinence. Next, a detailed immunocytochemical analysis of c-Fos activation was performed within seven nuclei of the amygdala. In the second experiment, c-Fos activation after reinstatement of ethanol seeking induced by discrete cues was compared with the activation pattern of its putative partner (c-Jun) and regulators (extracellular signalregulated kinases and c-Jun N-terminal kinases). Reexposure to ethanol-associated context cues (an extinction session) potentiated c-Fos expression within the basolateral and central amygdala. Repeated presentation of ethanol-associated discrete cues in an extinction/ reinstatement session led to even stronger c-Fos activation in the latter nuclei. In the second experiment, reexposure to the ethanolassociated context and discrete cues activated both c-Jun and extracellular signal-regulated kinases (ERK1/2) in the basolateral amygdala. Our observations suggest that the basolateral and central amygdala may be specifically involved in alcohol-seeking behavior induced by discrete cues.

Aims: Neuroimaging studies suggest a significant overlap between brain regions involved in the regulation of olfaction and mood. The aim of the present study was to search for correlations between depressive symptomatology measured by the 15-item Geriatric Depression Scale (GDS) and olfactory function assessed with Sniffin' Sticks in non-demented older adults (aged 53-79 years).Methods: Taste detection thresholds were also measured by means of electrogustometry on the anterior tongue. Results:No correlation was found between the GDS scores (range: 0-12) and olfactory thresholds or olfactory identification scores. Similarly, there was no relationship between depressive symptoms and electrogustometric thresholds. Subjects (n = 25) scoring Ն5 on the GDS were classified as 'depressed' and all other individuals (n = 60) were classified as 'nondepressed'. The two groups did not differ in terms of the olfactory measures and electrogustometric threshold. Conclusion:Depressive symptoms are not associated with any major olfactory deficit in non-clinical older adults.

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It is universally accepted that saliva plays an important role in taste sensations. However, interactions between constituents of whole saliva and the five basic taste modalities are still poorly understood. The aim of the present study was to evaluate possible relationship between endogenous glutamate (Glu) levels in whole saliva and taste responses to a prototypic umami substance, monosodium glutamate (MSG; 0.03-10.0%). Rated intensity and pleasantness of MSG taste was studied in healthy volunteers divided into a high glutamate (HG) in saliva (HG; n = 19) and low glutamate in saliva (LG; n = 18) group based on the median split level of salivary Glu. The HG and LG group did not differ in terms of electrogustometric thresholds, rated intensity of the MSG samples and pleasantness of distilled water and the lower MSG concentrations (0.03-1.0%). Perceived intensity of water taste was significantly (P < 0.05) higher in the LG subjects. The LG group rated the higher MSG concentrations (3.0-10.0%) as more unpleasant (P < 0.01). The difference remained significant after controlling for a between-group difference in age. The present results suggest that individual differences in salivary Glu levels may alter hedonic responses to suprathreshold MSG concentrations.