Behavioural and pharmacological effects of fluvoxamine on decision-making in food patches and the inter-temporal choices of domestic chicks

Abstract

 SSRI makes chicks commit less impulsive choices. SSRI makes chicks invest smaller efforts for food. SSRI makes chicks emit distress calls less frequently. SSRI increases 5-HT and DA levels in the medial striatum / nucleus accumbens. 3 AbstractBehavioural effects of fluvoxamine (FLV, selective serotonin reuptake inhibitor) were examined in 1-2 week old domestic chicks. Chicks were tested in an I-shaped maze equipped with a feeder (ON feeder) that served 1 or 2 grains of millet at gradually increasing intervals, so that a depleting food patch was mimicked. By leaving the feeder, the food delivery program was reset, and chicks gained food at short intervals only after a travel to a dummy feeder (OFF feeder) placed on the opposite side of the maze.Chicks quickly learned to actively shuttle between the ON and the OFF feeders. FLV (intra-peritoneal injection, 20 mg/kg BW) acutely caused chicks to stay longer at the gradually depleting ON feeder. Inter-temporal choices were also tested, whereby two colored beads were simultaneously presented, each associated with a small/short-delay reward or a large/long-delay alternative. FLV suppressed the choice of the short-delay option. It is suggested that an enhanced level of serotonin (5-HT) makes chicks more tolerant of the delayed food item in both behavioural paradigms. Furthermore, the decision to leave a depleting patch cannot be equated to choosing the long-delay option of the choice paradigm. Furthermore, FLV suppressed work efforts (velocity and running distance) in uncued shuttle and number of distress calls. In vivo microdialysis experiments revealed that FLV enhanced the extracellular concentration of 5-HT as well as dopamine (DA) locally in the medial striatum/nucleus accumbens. Underlying neuromodulatory mechanisms of behavioural control are examined in relation to locomotion, behavioural tolerance and interval timing.

Competitor suppresses neuronal representation of food reward in the nucleus accumbens/medial striatum of domestic chicks

“…Afferents from the raphe nuclei should also be considered, because a systemic application of fluvoxamine (selective serotonin reuptake inhibitor) made chicks commit less impulsive choices [6].…”

“…Choice impulsiveness has been a topic of intensive experimental research in a wide range of behavioral sciences, including psychology [1,2], psychopharmacology [3][4][5][6], behavioral ecology [7][8][9][10] and neuroscience [11][12][13][14][15][16]. To understand choice impulsiveness in a comprehensive manner, specifying the brain areas and networks that are specifically responsible for the choice of delayed reward is critical [17][18][19].…”

5-Hydroxytryptophan Suppresses the Abdominal Fat Deposit and Is Beneficial to the Intestinal Immune Function in Broilers

“…Moreover, the locomotor activity is higher in the line selected for high levels of feather pecking compared to control and the line selected for low levels of feather pecking (Kjaer, 2009). The acutely enhanced 5-HT level decreases motor activities of chicks (Matsunami et al, 2012). Hence, the involvement of locomotion activity on the energy expenditure remains to be elucidated.…”

Ecological Validity of Impulsive Choice: Consequences of Profitability-Based Short-Sighted Evaluation in the Producer-Scrounger Resource Competition

“…Actually, animals are less patient in the ITC task compared with their behaviors in natural foraging situations, and the temporal discounting measured in ITC task does not fit well with the decision to disengage. The underlying decision mechanism is also distinct, as pharmacological treatment using selective serotonin reuptake inhibitor (SSRI, fluvoxamine) suppressed impulsive choices but delayed the disengagement, contrary to the prediction based on the commonality [19]. Furthermore, the impulsivity measure can drastically change depending on how subjects are informed of the relevant parameters, such as the time after the food option was consumed (so-called postreward delay) [7,20].…”