The classic model of a sufferer of depression has them numb to or unable to see positive stimuli in their life and both talk therapy and SSRIs can help people recognise and maximize the positive things in life.

There’s a scenario colloquially referred to as “shit life syndrome” in which a sufferer is living in untenable and seemingly unchangeable circumstances, which are impacting their mental health. Therapy is largely ineffective here because it doesn’t affect the material aspects of life. It doesn’t stop abuse, it doesn’t put food on the table, it doesn’t make your workplace more tolerable, etc. There also seems to be a high level of correlation between this type of depression and cPTSD.

Interestingly, SLS-type depression may be a major cause of paradoxical reactions to SSRIs, where symptoms actually worsen. Unlike the traditional model of a depression sufferer, it’s not that SLS-type sufferers unable to see the positive stimuli in their life: they’re just overwhelmingly exposed to negative stimuli. Heightening the ability to engage with stimuli that were being missed instead results in a worsening of symptoms.