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  • Writer's pictureHollie

The Rat Experiment

I want to tell you a story about rats and relationships. It may seem like an odd pairing, but stick with me. In the 1980s, a couple of scientists conducted a behavioural experiment with a group of rats. They trained the rats to push a lever, and when they did, the rats received a pellet of food. The rats learned that performing this action would lead to a reward, and they started to associate this lever with meeting a core need - hunger.  But they weren’t hungry all the time, and the scientists observed that the rats eventually stopped pushing the lever as frequently.  You see, the rats trusted that when they pushed the lever, they would get a consistent and reliable reward, and so for the most part, they continued their normal rat behaviour - socialising, grooming, sleeping, etc. So far, so good.

Next, the scientists decided to remove the pellets and the rats began pushing the levers to no avail. Eventually, they learned that they were not going to receive a pellet because the outcome of pushing the lever was consistent and reliable. Over time, they lost interest - becoming less preoccupied with pushing the lever and more preoccupied with doing their normal rat things again. Understandable. We don’t often continue to do things when there is no compensation for our efforts. 


Both experiments so far had created a predictable pattern in terms of managing the rats' expectations. This is called continuous reinforcement and it’s the main process involved in  establishing (or conditioning) new behaviour, not only for rats, but for most beings. Have you ever taught a dog to sit, fetch, or roll over by giving them a treat, or been praised as a child for giving a correct response to a multiplication maths quiz? That’s the brain’s reward system at work. 


So what do you think happened when the schedule of reward in this experiment was made unpredictable? The scientists programmed it so that when the rat pushed the lever, sometimes a pellet would come out, but sometimes it wouldn’t. Their hypothesis was that this would frustrate the rat and eventually it would lose interest in the lever like before, but the complete opposite happened. 


All of the rats in the study became preoccupied with the lever - that is to say, they became obsessed! They stopped all of their regular rat behaviours like socialising or rearranging their nests. They started neglecting their self-care by not grooming or sleeping regularly. The quality of their lives diminished severely. The intermittent reinforcement of sporadically and unpredictably providing the pellet of food when they pushed the lever created an addiction, and even when the scientists put the pellets back in, their preoccupied nature didn’t change. 


When speaking about addiction we tend to gravitate towards matters like gambling, drugs, social media, sex, or gaming, but the truth is, we can become addicted (mentally, emotionally, or physically) to anything. Intermittent reinforcement conditioning digs deep into our subconscious because it’s tied to our survival needs and our internal rewards system. It can happen with any need or want that we have, and it is especially prevalent in relationships relative to emotional needs - things like commitment, affection, appreciation, closeness, or a sense of belonging. When a parent or caregiver is only able to occasionally and unpredictably meet these needs, it can create an unhealthy attachment style that leaves us obsessed with pushing the metaphorical lever. When it happens in our adult relationships, the toxic cycles of intermittent reinforcement can leave us feeling just like those addicted rats - anxious, neglected, and with an eroded sense of self. 


While we are most certainly not rats, this experiment sheds light on the complex dynamics of human behaviour and can help us understand our own struggles with attachment. Through self-awareness and reflection, we can start to recognize these patterns for what they are and take steps towards breaking them. In addition to its valuable insights, the rat experiment offers a path to healing from the effects of intermittent reinforcement in relationships because it underscores the importance of prioritising and nurturing healthy, reliable connections (especially the connection with yourself). When we nurture foundations of trust, self-compassion, and authenticity, we can start to heal from the detrimental patterns that have diminished our sense of safety and stability throughout life. Consistency is the key.


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