Journal: Nature Communications

Article Title: Saccades orchestrate intraocular glucose dynamics to shape visual responses in birds

doi: 10.1038/s41467-026-70672-0

Figure Lengend Snippet: a Example electrooculography recordings of saccades from five avian species: pigeon, duck, chukar, budgerigar, and chicken. Scale bars (left to right): 150 ms; 0.28, 0.25, 0.20, 0.34, and 0.25 mV. b Schematic drawing of the intraocular glucose monitoring (CGM) and eye movement (EOG) recording systems in awake, head-fixed pigeons – viewing bilateral visual displays. c The definition of saccade frequency, oscillation frequency, and intrasaccadic frequency. d Comparison of three frequencies under different visual conditions: light (L), dark (D), gray (G) screens and social mating videos (V) (one-way ANOVA: saccade frequency: n = 87 (L), 115 (D), 287 (G), 286 (V), F (3,771) = 45.26, p < 0.001, oscillation frequency: n = 86 (L), 115 (D), 288 (G), 283 (V), F (3,768) = 11.32, p < 0.001, intrasaccadic frequency: n = 82 (L), 111 (D), 290 (G), 286 (V), F (3,765) = 0.79, p = 0.50). Violin plots depict the distribution of measurement frequencies, whereas bar plots show the normalized mean frequencies for each visual condition, averaged across three pigeons (mean ± SD). *** p < 0.001, n.s. not significant. e Relationship between saccade frequency and oscillation frequency under four conditions. f Schematic diagram illustrating the dark-to-light screen transition. Normalized traces of saccade frequency ( g ), oscillation frequency ( h ), and glucose levels ( i ) during the transition from dark to light screens. The white lines with color shading represent the mean ± SD ( n = 6 pigeons), and the gray lines indicate data from individual animals. j Cross-correlation analysis of the time lag between eye movements and intraocular glucose levels aligned to the dark-to-light transition. Dashed lines indicate the peak time lags. The shaded area represents the 95% confidence interval of the null distribution (generated via shuffling), with correlations above this area considered statistically significant. k – o Same as ( f – j ), but for the transition from light to dark screens. p Schematic diagram illustrating pigeon social mating videos. q Average result of four pigeons exhibited increased saccadic eye movements and intraocular glucose levels while viewing 30-min conspecific social mating videos. r Same cross-correlation analysis as in ( j ), but aligned to the switch to social video. The shaded area represents the 95% confidence interval of the null distribution (generated via shuffling). Source data are provided as a file.

Article Snippet: In this study, assessments of glucose levels involve measuring the concentration of glucose in intraocular fluid and interstitial fluid of pectoral muscles, via the Continuous Glucose Monitoring (CGM) systems (Freestyle Libre 2 CGM System, Abbott, USA; GS1 CGM System, SIBIONICS, China) and the glucometer (Accu-Chek Active, Roche, Switzerland).

Techniques: Comparison, Generated