Effect of nucleus accumbens lesions on socially motivated behaviour of young domestic chicks

Abstract

Behaviour of young domestic chicks when isolated from conspecifics is influenced by two conflicting drives: fear of potential predator and craving for company. The nucleus accumbens (Ac) has been suggested to influence social behaviour, as well as motivation in goal-directed tasks. In this study, the Ac of 1-day-old domestic chicks was lesioned bilaterally, using radiofrequency method. Open field behaviour before and after presenting a silhouette of a bird of prey was recorded, followed by a behavioural test to measure group size preference and social motivation of chicks. Ac-lesioned individuals emitted more distress calls and ambulated more in the open field test, however, they reacted to the predatory stimulus very similarly to control chicks: their vocalization was reduced and the intergroup difference in motor activity also disappeared. There was no difference between the lesioned and control chicks in the latency to approach their conspecifics in the social motivation test, and both groups chose the larger flock (eight) of conspecifics over the smaller one (three). Concerning the role of Ac in social behaviour, a difference between lesioned and sham birds was evident here only in the absence of detectable stimulus (predator or conspecifics). These findings may reflect either decreased fear of exposure to predators or increased craving for conspecifics suggesting that the likely function of Ac is to modulate goal-driven, including socially driven, behaviours, especially when the direct stimulus representing the goal is absent. This is in harmony with the known promotion of impulsiveness by Ac lesions.

Fos expression in the medial preoptic area and nucleus accumbens of female Japanese quail (Coturnix japonica) after maternal induction and interaction with chicks

“…As mentioned above, components of the NAC process both the salience and valence of rewarding stimuli in many animals including birds (Cooper and Knutson, 2008;Levita et al 2009;Riters et al, 2013;Zachar et al, 2017). We found a significant main effect of maternal sensitization, but not of exposure to chicks again before euthanasia, on the number of Fos-ir cells.…”

“…In addition to measuring Fos expression in their mPOA, we also measured Fos expression in the nucleus accumbens (NAC) and lateral ventral bed nucleus of the stria terminalis (BSTL). The NAC processes both the salience and valence of rewarding stimuli in many animals, including birds (Cooper and Knutson, 2008;Levita et al 2009;Riters et al, 2013;Zachar et al, 2017), so may somewhat differ than the mPOA in its response to chicks. The BSTL is part of the "extended amygdala" system underlying endocrine and anxiety-like responses to stressors (Cecci et la., 2002;Morilak et al 2003;Walker et al 2009), including in birds (Nagarajan et al, 2014).…”

Age-related and function-dependent regional alterations of free L- and D-aspartate in postembryonic chick brain

“…Implantation coordinates were 4.0 mm anterior from bregma, 0.85 mm lateral from midline and 5.8 mm ventral from brain surface. The coordinates were in agreement with previous lesion and pathway tracing studies on the ventrobasal forebrain of the domestic chicken [3,26,46]. After the implantation, the animals were allowed to recover from the operation for at least 12 h without food and water (this is standard procedure for day-old domestic chicks supported by their yolk sac).…”

Valproate Exposure in ovo Attenuates the Acquisition of Social Preferences of Young Post-hatch Domestic Chicks

“…One widely used behavioral paradigm is filial imprinting (Horn, 1998; Matsushima et al, 2003), which is not entirely devoid of social context, since it is the trigger of social bond forming between parent and offspring. Chicks also react to social isolation by displaying behaviors aimed at reuniting with conspecifics (Gallup and Suarez, 1980), and they prefer larger groups of siblings over smaller ones (Zachar et al, 2016). The drive to reinstatement can be evaluated by measurement of distress vocalization (Takeuchi et al, 1996; Yazaki et al, 1999).…”

“…Based upon previous findings in mammals, we chose to investigate another, phylogenetically distant species, the domestic chicken. Newly hatched chicks of Galliform birds are known to display various types of preference behavior, e.g., genetically determined preference for color of Japanese quail (Kovach, 1980; Csillag et al, 1995), or predispositions toward social stimuli of domestic chicks (Zachar et al, 2008, 2016; Di Giorgio et al, 2016). A precocial nidifugous species with a remarkably mature brain structure at hatching, the domestic chicken has long been used for investigation of early adaptive learning (imprinting or passive avoidance training, for an overview, see Rose, 2000), and it also appears to be a useful model for studying the effect of embryonic VPA treatment on acquired and innate behaviors.…”