FIGURE 4.

CSF log kunurenic acid/kynurenine ratio in response to the repeated separation paradigm as a function of variable foraging demand exposure during early life. There is a repeated separation paradigm (RSP)*VFD interactive effect for CSF log KYNA/KYN obtained from the CSF following the RSP phase (F₁,₃₀ = 12.12; p = 0.0016) (see Figure 1). CSF log KYNA/KYN is lower in non-VFD subjects who were exposed to the RSP (N = 17) in comparison to those who did not (N = 5; p = 0.0001), whereas VFD exposed to the RSP (N = 8) exhibited significantly increased CSF log KYNA/KYN ratios in comparison to no-RSP-exposed VFD subjects (N = 4; p = 0.04). Non-VFD unexposed to RSP exhibited exhibited greater CSF log KYNA/KYN in comparson to VFD unexposed to RSP (p = 0.00001). By contrast, post-exposure to RSP, VFD and non-VFD exposed are not distinguishable (p = 0.66). Abbreviations: VFD, variable foraging demand; KYNA, kynurenic acid; KYN, kynurenine; CSF, cerebrospinal fluid; RSP, repeated separation paradigm.