Figure 4
Schematic depicting the response to threat during the human intruder anxiety test. The graph indicates the probability of engaging in different behaviors in relation to the perceived intensity of threat. The normal range population described by our principal component analysis is shaded in gray. The AC/C/G group perceive the human intruder as a relatively high threat, showing high numbers of bobbing events, reduced locomotion and jumps, and primarily avoidance of the threat (reduced risk assessment). The CT/T/C group perceive the human intruder as a lower threat, showing fewer numbers of bobbing events, increased locomotion and jumps, and approach behavior to the threat (increased risk assessment/approach). Acute selective serotonin reuptake inhibitor (SSRI) in the AC/C/G group produces an anxiogenic effect with avoidance of the threat and further reduction in locomotion, jumps, and numbers of bobbing events, leading to an anxious state of stillness. In contrast, acute SSRI in the CT/T/C group induces an anxiolytic effect leading to increased approach behavior (increased inspection/risk assessment of the human intruder), with concomitant reduction in locomotion and jumps.
