Caffeine affects the vigilance decrement of Trite planiceps jumping spiders (Salticidae).

Abstract

In jumping spiders (Salticidae), the vigilance decrement, or decrease in response to a repeated visual stimulus over time, directly parallels that found in humans. Explanations for the vigilance decrement in the human literature are heavily mentalistic and central nervous system (CNS)-based, whereas response decrements in invertebrates are typically thought of as habituation at the sensory periphery. Here we explored whether the salticid vigilance decrement could be CNS-modulated by using caffeine, which is a well-known CNS stimulant for both vertebrates and invertebrates. We used paired tests in which Trite planiceps Simon spiders were randomly given either a drop of caffeinated water or distilled water and were then shown dot stimuli presented on monitors. We measured both general 'walking', or activity, as a control for physical fatigue, and optomotor responses to the stimuli. We found that the vigilance decrement was significantly shallower (i.e., spiders were more responsive for longer) when spiders were administered caffeine compared with water; furthermore, these spiders were also generally more active throughout the testing period and thus were not physically impaired. Our results suggest that, in at least in some invertebrates, CNS modulation of the vigilance decrement is likely.

Separate attentional processes in the two visual systems of jumping spiders

“…Similarly, we observed a reduction in the response rate between trials within the same session in both our experiments. This is also in line with previous literature showing that jumping spiders' detection rate drops following repeated stimulus presentation (De Agrò et al, 2021;Humphrey et al, 2018Humphrey et al, , 2019Melrose et al, 2018).…”

Acute exposure to caffeine improves foraging in an invasive ant

“…However, a recent study exploring visual learning in bumblebees shows GABA promoting flower fidelity. 73 Caffeine has been shown to increase responsiveness and activity in jumping spiders 74 as well as having an effect on locomotion in a variety of insects. 67 However, we show no effect of caffeine on ant mean instantaneous speed throughout the foraging journey, further suggesting caffeine-mediated foraging improvements are not a consequence of motor efficiency but rather of cognitive enhancement.…”

Acute exposure to caffeine improves navigation in an invasive ant

“…However, a recent study exploring visual learning in bumblebees shows GABA promoting flower fidelity (Calderai et al ., 2023). Caffeine has been shown to increase responsiveness and activity in jumping spiders (Humphrey, Helton & Nelson, 2019) as well as having an effect on locomotion in a variety of insects (Mustard, 2014). However, we show no effect of caffeine on ant mean instantaneous speed throughout the foraging journey, suggesting caffeine-mediated navigational improvements are not a consequence of motor efficiency but rather of cognitive enhancement.…”