<p>Anthropogenic noise pollution is a major global stressor that affects vertebrate physiology and behaviour. However, at present, little is known about the impacts of anthropogenic noise on cognition. To evaluate the effects of noise on fish cognition, we utilized an associative learning protocol. We trained adult zebra danios <i>(Danio rerio</i>) to associate a red card located in one arm of a maze with the presence of conspecifics, usually a positive reward for these social fish. Immediately afterwards we exposed the zebrafish to either no noise (control) or one of four noise treatments (white noise, at high or medium intensity crossed with either a regular or irregular pattern) then tested their learning in the absence of noise. Furthermore, to understand the possible molecular mechanism underlying any neuro-behavioural effects, we also quantified the changes in gamma-aminobutyric acid (GABA) level in zebrafish brain. Our results showed that control fish learned the location of the social reward as evident by their attraction to the correct maze arm. Noise exposure impaired cognition as evident by the lowered time these fish spent in the target arm of the maze compared to control fish. Noise intensity did not appear to influence maze performance, but the irregular pattern of noise resulted in poorer performance in the maze. Most interestingly, fish in the irregular noise treatments showed significant avoidance of the target arm compared to random chance. Our results suggest that zebrafish were unable to learn the association of the red arm with the presence of conspecifics in the presence of noise, or alternatively that they did learn but the presence of conspecifics was devalued as a reward. This study highlights that anthropogenic noise can have far reaching and paradoxical ecological consequences.</p>