A recent study published in the journal Neuropsychopharmacology, revealed that using a Selective Serotonin Reuptake Inhibitors (SSRI) for three weeks made healthy volunteers less receptive to positive and negative feedback. The "blunting" of unpleasant feelings may contribute to the medications′ ability to aid in depression recovery while also explaining a common adverse effect.

Over 8.3 million individuals in England took depressive medication in 2021–2022, according to the NHS. In the majority of the patients, SSRIs are effective and is the most commonly prescribed medications.

The current study included 66 participants who either received escitalopram (an SSRI) or a placebo for at least 21 days before taking a set of cognitive tests. 

The medicine had no effect on practically any tests measuring attention and memory. Additionally, less response was seen in the reinforcement learning, which necessitates a response to either positive or negative feedback, among SSRI users. The participants were shown two alternatives in screens A and B. If option A was chosen, a reward would be gained about four out of every five times, compared to choosing option B, which gave a reward of once every five times. People eventually learn to select A after a few turns. The probability was changed occasionally, and the participants had to learn the new rule. Overall, the SSRI group took much longer to react to these modifications in feedback. Another side-effect frequently mentioned by patients related to sexual function.

Experts stated that the findings might benefit patients′ awareness of the side effects. The conclusions provided crucial information about how SSRI medications work on relevant patients and may assist in developing newer drugs with fewer side effects and better drug profiles. 

(Source: https://www.theguardian.com/society/2023/jan/23/antidepressants-emotional-blunting-study)