Will an antidepressant help with such a symptom of depression as a decrease in intellectual performance?

If the decrease in intellectual performance is the result of depression with secondary cognitive deterioration, then as the depressive syndrome is treated, these ailments may disappear. In other words, if a patient's cognitive impairment is an integral part of depression, antidepressants will also help with this symptom. However, in the case when the symptoms of depression are only an early manifestation of dementia, which is not the result of depression, but another disease or simply age, the resolution of depression symptoms will not improve cognitive functions. It is also possible that dementia and problems associated with the loss of intellectual functions are the cause of depression. In this case, treatment will improve the mood and well-being of the patient, but will not affect mental performance. I enclose information that may be of interest: https://www.gdziepolek.pl/artykuly/depresja https://www.gdziepolek.pl/kategorie/leki-na-depresje