Figure 1.

Chronic sensory pain induces anxiety- and depression-like behaviors with significant individual variance. A, Mechanical pain thresholds in sham-operated rats and in rats with CCI of the ION up to 28 d after the surgery. B, Distribution of mechanical pain thresholds (EF₅₀) in individual rats 28 d after CCI-ION surgery. C, Traces of locomotor activity (top) and the time rats spent in the central zone (central time, bottom) in an open field test in sham rats and CCI-ION rats. D, Individual data of central time in the same rats as in C, with the CCI-ION rats divided into a vulnerable group (Vul; defined by the central time of each CCI-ION rat below the averaged central time in sham rats, n = 17) and a resistant group (Res; with central time above the sham average, n = 5). E, F, Average group data of distance traveled (E) and travel velocity (F) in the sham rats and CCI-ION rats. G, H, Individual data of distance traveled (G) and travel velocity (H) in the same rats as in E and F. I, J, Group averages (I) and individual data (J) of immobility time in the forced swim test in the sham rats and CCI-ION rats. CCI-ION rats were divided into a vulnerable group (immobility time above sham average, n = 18) and a resistant group (immobility time below sham average, n = 4). K, Immobility time of depressive behavior in sham rats, in anxiety-vulnerable CCI-ION rats (Anx-Vul; n = 17), and in anxiety-resistant CCI-ION rats (Anx-Res; n = 5). L, Central time of anxiety behavior in sham rats, in depression-vulnerable CCI-ION rats (Depr-Vul; n = 18), and in depression-resistant CCI-ION rats (Depr-Res; n = 4). N = 22 both in the sham group and the CCI-ION group. Errors bars are SEM. *p < 0.05, **p < 0.01, ****p < 0.0001.