The key trick used by behaviorists is to allow only one isolated stimulus and one correct response at a time in an artificial laboratory situation.
But in real life, there are always multiple stimuli and multiple response options simultaneously!
The processing of a stimulus usually involves:
- Discrimination: e.g., a mimosa can distinguish between a touch and a raindrop
- Differentiation (is the stimulus essential or accidental) <=> (signal <=> noise) context dependence
- Interpretation
- Habituation – sensitization
- Anticipation – expectation – learning experience, mood, appetence, set…
The natural process of “conditioning” as an adaptation to environmental conditions is therefore very complex in real life!
Therefore, multiple repetitions are necessary to prevent coincidentally occurring stimuli and responses from being considered causally linked.
The dog sits and receives a treat. But was it the command, the hand gesture, the shrug, the wink, the bird’s chirp… that prompted it? It’s clear to us because we said “sit” – but not to the dog the first time.
And in real life, there are so many other tempting things besides treats. A deer track, a bitch in heat…
Furthermore, an aversive stimulus can trigger a fight-or-flight response. But only when a certain threshold is exceeded, when the critical distance is undercut.
Stimuli can also add up if two or more aversives, which individually wouldn’t lead to a catastrophic reaction, occur simultaneously, and the sum of the stimuli exceeds the threshold.
An objectively harmless, usually unidentifiable stimulus can trigger a flashback, a catastrophic reaction with complete loss of control and extreme aggression, due to a previous trauma.

