Individual gustatory reaction times to various groups of chemicals that provoke basic taste qualities

Abstract

Reaction times (RTs) to four groups of substances that provoke different taste qualities were measured. Measurements for all substances with the same taste, equalized in perceived intensity and provoking a very strong taste, were made concurrently for each subject. The comparisons were made on the individual level. No significant differences in RTs to substances with the same taste quality were found. When the factor of perceived intensity is kept constant, no effect of the stimulus chemical composition on RTs seems to be present. RTs to stimuli with different tastes differ significantly, the shortest being to salt and the longest to bitter. The difference in RTs for sour and sweet substances is small, and the subjects were not all alike in terms of the order of RTs with respect to these stimuli.Although by far the dominant part of total reaction time (RT) is attributable to the time of cortical processing events (Halpern, 1986), some significant differences in RTs to various taste substances imply that the time of receptor-organ events can also playa detectable role. In fact, some investigators, on the basis of their gustatory RT results, have made certain remarks concerning the similarity or dissimilarity in the receptor transduction process. But these RT comparisons have been limited to various salt and sweet substances (yamamoto, Kato, Matsuo, Kawamura, & Yoshida, 1985;Yamamoto & Kawamura, 1984) or to a few stimuli that evoke a sour taste (Bujas, Szabo, Mayer, Ajdukovic, & Vodanovic, 1989). Also, in some of these studies, the different subjects have been stimulated by different substances, so that a great intervariability could have distorted the comparison results.The purpose of the present study was to obtain, if possible, some information on the receptor transduction mechanism by comparing RTs to various typical substances with the same taste quality, with the same subjects being exposed to all the stimuli used. Because the taste RT for a substance varies widely with its taste intensity, it was necessary, within each group of substances and for each individual subject, to equalize perceived taste intensities carefully. To diminish the influence of each subject's intravariability from session to session, all RT Correspondence may be sent to Silvija Szabo, Department of Psychology, Filozofski fakultet, University of Zagreb, Dj. Salaja 3,41000 Zagreb, Yugoslavia. measurements for substances with the same taste quality were made concurrently. Moreover, to have a common reference point, the RTs to l.OM NaCl in all sessions were determined. METHOD Apparatus and StimuliTaste stimuli were applied to the anterior part of the tongue by a gravity flow system. To assure an initially uniform hydrodynamic pressure of the liquid against the tongue surface, a siphon container was used. From this container, the solution flowed through three channels at 6 ml/sec over a tongue area of about 7 em', eliciting, at contact, only a slight touch sensation. The stimulus duration time was 5 sec. The solutions were warmed to 38°C.Fo...

Measurement of Human Brain Activity Evoked by Stimulation of Beer Bitterness Using Magnetoencephalography

“…Bujas (1989) showed that the reaction times to 4 groups of taste substances were 373 Ϯ 58.86 ms for salts (NaCl, LiCl), 559 Ϯ 107.61 ms for acids (HCl, citric acid), 602 Ϯ 89.18 ms for sweetness (sucrose, saccharin), and 864 Ϯ 159.60 ms for QHCl, which agreed with our results such that the activity for bitter taste was later than the salty and sweet tastes. He measured the reaction time when the subject stopped the chronometer by manual release of a switch at the moment of taste recogni- tion.…”

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First objective evaluation of taste sensitivity to 6-n-propylthiouracil (PROP), a paradigm gustatory stimulus in humans

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Temporal Characteristics of Gustatory Responses in Rat Parabrachial Neurons Vary by Stimulus and Chemosensitive Neuron Type

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