In this series, I dig a little deeper into the meaning of psychological terms. This week’s term is exposure and response prevention.
Exposure and response prevention (ERP) is a type of cognitive behavioural therapy used to treat obsessive compulsive disorder (OCD). It’s similar to prolonged exposure therapy, which is used in anxiety disorders and PTSD, but it has the added piece of response prevention. The client is exposed to anxiety-provoking stimuli that trigger the obsessive thoughts, and then makes a deliberate choice to force themselves not to respond to those thoughts by performing a compulsive behaviour ritual.
Near the start of therapy, a fear ladder is constructed. This ranks different stimuli in terms of the level of fear they provoke. Work begins on the least feared stimuli and then move up the ladder as the therapy progressed.
Prevention of the compulsive behavioural response results in habituation, as the fear response decreases with repeated exposure to the anxiety-provoking stimuli. This takes some time, so there must be a strong commitment to the therapy to be able to make choices that won’t decrease anxiety in the short-term, and may actually increase anxiety and agitation initially.
New learning is instilled about the temporary nature of the fight-or-flight response, and the natural tendency of the parasympathetic nervous system to kick in after about an hour of exposure to settle down the physiological response. As behaviours change, more balanced cognitions are established, which then produces changes in emotional response.
When a feared outcome is something that may or may not occur, the focus isn’t on proving that it’s unlikely; instead, the aim is to learn to better tolerate uncertainty without resorting to compulsive behaviours. Learning around uncertainty also occurs in relation to the connection between feared stimuli/outcomes and the presence of obsessions – sometimes the two are connected, but other times they aren’t, meaning they’re not inextricably linked.
Extinction occurs when the client is able to establish through ERP that the feared outcome is unlikely and the formerly anxiety-provoking stimuli are not dangerous. This is a type of implicit learning, which is learned through practice rather than simply being told by someone else that the stimulus is safe.
OCD hijacks the natural danger response system, sending out alarm signals that aren’t based in actual danger. Responding as though a stimulus is actually dangerous ends up feeding into the faulty alarm system, and further impairing the brain’s ability to distinguish between safe and unsafe.
Starting ERP can seem profoundly counterintuitive since it goes against the message that the brain is screaming. However, it has been demonstrated to be effective for OCD, and more effective than talk-focused therapies. It is as effective as medication and has more lasting effects.
Have you ever tried ERP therapy? How has it worked for you?
You can find the rest of the What Is series here.