Shoaling in zebrafish: From animated images to neurobiological mechanisms (#89)
Social behaviour is a defining feature of our own species but the analysis of its mechanisms is complicated by numerous scientific and ethical issues. The zebrafish is a simple vertebrate with high translational relevance for biomedical research, and it also happens to be a highly social laboratory organism. We have been exploring different methods of inducing a specific form of social behaviour, shoaling (or group forming) in the zebrafish with the ultimate goal of using these methods for the analysis of the neurobiological mechanisms of social behaviour. In this paper we will review some of these methods. We will discuss findings that show that presentation of 2-dimensional moving images of conspecifics may be sufficient to induce robust shoaling responses. We also explore such questions as what the ideal shoal composition may be (numerical size, sex, colour and pattern of shoal members). We demonstrate that the sight of conspecifics is rewarding, and also show that the appearance of conspecific images selectively activates the dopaminergic system of the observing zebrafish. Furthermore, we show that selective pharmacological blockade of the D1 dopamine receptor abolishes shoaling in zebrafish. Last, we briefly review an example that illustrates how the animated image-based shoaling paradigm may be utilized in the analysis of the effects of drugs of abuse, e.g. alcohol.