The Recording of Licking Behavior

Analysis of the microstructure of the rhythmic tongue movements of rats ingesting maltose and sucrose solutions.

“…The mean and standard deviation within-burst ILIs for flush, 1.5 mm away, and 3.0 mm away were 0.155 ± 0.003, 0.164 ± 0.002 and 0.169 ± 0.003, respectively, differences that were highly significant, F(2, 10) = 24.1, p < .001. This replicates results reported by Knowler and Ukena (1973) and by Weijnen (1977). The means of the IBI distributions, however, were not affected by this manipulation (means and standard deviations were 0.331 ± 0.007, 0.332 ± 0.006, and 0.335 ± 0.003, respectively (F = 0.183).…”

“…Visual inspection of the distribution of ILIs longer than 250 ms indicates that this distribution can be divided into two categories, one consisting of ILIs in the range 250 to 500 ms ( Figure 3, right panel) and the other consisting of ILIs longer than 500 ms ( Figure 4). This bimodal distribution was first noted by Corbitt and Luschei (1969), and it can be seen in more recently published ILI frequency distributions (Gramling et al, 1984;Hsiao & Spencer, 1983;Weijnen, 1977). The first distribution is the within-burst distribution described earlier; the second distribution, which covers the range of ILIs from 251 to 500 ms, is symmetrical, with a mean and standard deviation about twice that of the within-burst distribution.…”

“…Knowler and Ukena (1973) and Weijnen (1977) have reported that lick rate decreases as the drinking tube is made more inaccessible. Thus, if the IBI distribution is a true first harmonic of the within-burst distribution and represents maintained contacts with the tube or missed licks, then moving the tube farther from the reach of the animal should shift both of these distributions to the right.…”

Roux-en-Y gastric bypass in rats increases sucrose taste-related motivated behavior independent of pharmacological GLP-1-receptor modulation

“…Our measures for each phase of the studies in which brief-access performance was measured consisted of the following: 1) the number of licks of water taken and interlick interval (ILI) during the 2nd day of testing during which water was presented from a stationary spout; 2) the lick score, defined as the mean number of licks taken per trial of each sucrose concentration less the mean number of licks taken per trial of water during testing with the sucrose concentration series; and 3) the number of trials initiated by the rats during each session. The individual ILIs, which, under constant test conditions, are relatively invariant in rodents (15,64,69,71) and, ultimately, place a limit on the maximal lick rate, were filtered to include those between 50 and 250 ms in duration, because values Ͻ50 ms were considered double licks, and those values Ͼ250 ms were considered pauses between licking bursts (17); the individual ILIs meeting the criterion were averaged across session. Only rats that had initiated at least two trials of each concentration across the days that they were tested in each phase were included in the statistical analysis of lick score.…”

Localization of the central rhythm generator involved in spontaneous consummatory licking in rats: functional ablation and electrical brain stimulation studies.

“…6 and 7; for a review, see ref. 8) but can be modified within certain limits by the accessibility of the spout and the length of tongue travel required to reach the spout (9,10 (12,17,18). The neurons of these nuclei, the solitary nucleus, and the spinal trigeminal complex were identified as brain stem afferents to the hypoglossal nucleus (19).…”