But here again

But here again, we are prompted to question the reliability as this investigation by Tang et al (2009) found a few unexpected results, for example, depression reduction was substantial during the placebo phase and less so during the paroxetine phase. So, changes in personality showed the opposite pattern, therefore conflicting with their original hypothesis.
The delay in impact of SSRI’s on mood has been long debated. Pringle and Harmer (2015) suggest a lag between the administration of treatment and changes to mood to be a result of the need for relearning of emotional associations which is only possible over a course of time whilst the patient immerses themselves within their social environment in the context of the modified processing bias. From this, Pringle and Harmer (2015) surmise that the immediate impact of antidepressant treatment is to remediate biased emotional processing and alongside social behaviour, this will eventually result in an improvement in mood.
Whilst the impact of SSRI’s or monoamines (neurotransmitters such as serotonin which consist of one amino group) tend to prove to have a positive impact on mood, faster alternatives have been investigated. As noted by Pringle and Harmer (2015), even Alec Coppen (1967), one of the pioneers of antidepressant treatment, claimed that a lack of monoamine isn’t the sole contributor to depression and whilst responsiveness in patients is evident via the likes of tryptophan, the effects aren’t as quick or effective as with ECT. Electroconvulsive therapy, a brain stimulation technique, is known to make changes in the brain that can quickly reverse symptoms of certain mental illness and whilst Pringle and Harmer (2015) suggest that it takes around 2 to 6 weeks before effects are seen in antidepressant treatment, faster results are seen via alternate procedures such as ECT.
Whilst the cognitive neuropsychological theory of Harmer and Cowen (2013) is markedly different in response to what Young, Moskowitz and aan het Rot (2014) have provided evidence for, the two theories aren’t mutually exclusive. Both implicate antidepressants in a shift in mood and behaviour to stimuli – the former presents us with a model which sees impact towards positive reactions to nondescript and positive stimuli and the latter sees changes within a social setting.
Interestingly, Young, Moskowitz and aan het Rot (2014) suggest a domino effect in that as the antidepressants tend to alter mood from a negative bias to a more positive one, that in turn would encourage a more agreeable behaviour anyway when interacting with others. Consequently, these favourable interactions would impact mood in an encouraging way. This is verified by Tang et al’s (2009) state effect hypothesis with regards to SSRI treatment where they claim that as depression improves, the state effect of depression declines, therefore any personality change is a by-product of depression improvement.
Whilst it’s evident that SSRI’s are impactful in the processing of emotions such as fear and hostility and can influence behaviour within a social context such as affiliation and cooperation, the degree of impact of this group of drugs is variable. The plethora of research suggests that these theories hold some substance and whilst Harmer et al (2013) and Young et al (2014) are able to substantiate their findings with cogent evidence, the lack of consistency in results across the board, indicates that there is still work to be done.