Figure 1.

Overall relation of approach (BAS), avoidance (FFFS=fight, freeze, flee) and conflict (BIS=behavioural inhibition) systems—an updated model. The inputs to the system are classified in terms of the delivery (+) or omission (−) of primary positive reinforcers (PosR) or primary negative reinforcers (NegR) or conditional stimuli (CS) or innate stimuli (IS) that predict such primary events. The BIS is activated when it detects approach-avoidance conflict—suppressing prepotent responses and eliciting risk assessment and displacement behaviours. The systems interact in a variety of ways to generate behaviour, see text. The shaded areas are all points at which traits appear to operate. Figure and legend from McNaughton and Corr¹³ modified from Gray and McNaughton⁶ and Corr and McNaughton.⁴⁷ BAS, behavioural approach system.