Université de Toulouse, UPS, Research Centre on Animal Cognition, 118 route de Narbonne, 31062 Toulouse Cedex 9, France.
J Exp Biol. 2011 Nov 1;214(Pt 21):3577-87. doi: 10.1242/jeb.062026.
Visual performances of honeybees have been extensively studied using free-flying individuals trained to choose visual stimuli paired with sucrose reward. By contrast, harnessed bees in the laboratory were not thought to be capable of learning a Pavlovian association between a visual stimulus (CS) and sucrose reward (US). For reasons as yet unknown, harnessed bees only learn visual cues in association with sucrose if their antennae are ablated. However, slow acquisition and low retention performances are obtained in this case. Here, we established a novel visual conditioning protocol, which allows studying visual learning and memory in intact harnessed bees in the laboratory. This protocol consists of conditioning the sting extension reflex (SER) by pairing a visual stimulus (CS+) with an electric shock punishment (US), and a different visual stimulus (CS-) with the absence of shock. Bees with intact antennae learned the discrimination between CS+ and CS- by using chromatic cues, achromatic cues or both. Antennae ablation was not only unnecessary for learning to occur but it even impaired visual SER conditioning because of a concomitant reduction of responsiveness to the electric shock. We thus established the first visual conditioning protocol on harnessed honeybees that does not require injuring the experimental subjects. This novel experimental approach opens new doors for accessing the neural correlates of visual learning and memory in honeybees.
蜜蜂的视觉表现已经通过对经过训练的自由飞行个体进行广泛研究,这些个体被训练成选择与蔗糖奖励配对的视觉刺激。相比之下,实验室中的束缚蜜蜂被认为不能学习视觉刺激(CS)和蔗糖奖励(US)之间的巴甫洛夫式关联。由于未知的原因,如果束缚蜜蜂的触角被切除,它们只能学会与蔗糖相关的视觉线索。然而,在这种情况下,只能获得缓慢的习得和低的保留表现。在这里,我们建立了一个新的视觉条件反射协议,该协议允许在实验室中研究完整束缚蜜蜂的视觉学习和记忆。该协议通过将视觉刺激(CS+)与电击惩罚(US)配对来调节刺延伸反射(SER),并将不同的视觉刺激(CS-)与电击的不存在配对。具有完整触角的蜜蜂通过使用色觉线索、非色觉线索或两者结合来学习 CS+和 CS-之间的区分。触角切除不仅对学习的发生没有必要,而且由于对电击的反应性同时降低,甚至会损害视觉 SER 条件反射。因此,我们建立了第一个不需要伤害实验对象的束缚蜜蜂视觉条件反射协议。这种新的实验方法为探索蜜蜂视觉学习和记忆的神经相关因素开辟了新的途径。