Seat-belts and behavioural adaptation: the loss of looming as a negative reinforcer

Janssen has shown that drivers adopt slightly higher speeds and shorter following distances over the year after they switch from non-use to use of seat-belts. Does such behavioural adaptation continue to grow, so that the benefit for seat-belt users becomes dubious? One problem in answering this has been the weak theoretical basis of behavioural adaptation. In this paper, Fuller's learning model is developed as an alternative. The sharp braking associated with near-misses and other circumstances pitches an unbelted motorist towards the internal fittings of the automobile, thus eliciting rapidly accelerating visual expansion leading to defensive and fear responses. This looming phenomenon acts as a negative reinforcer by which safer driving behaviours become learnt. Seat-belt use removes looming. Learning due to negative reinforcement is persistent, so those switching from non-use to use of seat-belts only lose their safer driving behaviours over a long time. Also, in the years after seatbelt legislation is introduced increasing numbers of new licence-holders will have always used seat-belts, so looming will never affect their learning. This analysis suggests that seat-belt use has dubious long-term effectiveness for motorists, while engendering a more dangerous roadway environment for non-motorists. (C) 2001 Elsevier Science Ltd. All rights reserved.