Posted by linkadge on January 8, 2006, at 8:32:36
In reply to Cognition, Depression, and AD's, posted by law663 on January 7, 2006, at 23:11:42
Depression itself probably causes memory impairment via a combination of structural and biochemical abnormailites.
There have been some patterns of brain atrophy noted in patients with family histories of depression. Generally glial reductions in the frontal cortex, general grey matter reductions, and of course hippocampal volume loss.
Peturbations of monoamine function may affect memory, attention, and drive.
Many antidepressants tend to work by functionally supressing cholinergic function.Even when the drug is not a direct anticholinergic, like say effexor, it may have
a net anticholinergic effect, by boosting noradrenaline.There are other theories too. SSRI's may supress or dampen certain dopaminergic pathways, which is critical for functional cognition. SSRI's can often reduce dopamine and noradrenaline in the frontal cortex, with the exception of perhaps fluoxetine. The net result may be executive dysfunction.
As well, agonism at certain serotonin receptors facilitates memory, and agonism at others seem to supress it, so taking a drug that acts as an agonist to all serotonin receptors can have a mixed effect on cognition.
On SSRI's I generally experienced reduced ability to concentrate for extended periods of time, as well as a general sort of brain fog where most ideas were harder to grasp.
Linkadge
poster:linkadge
thread:596407
URL: http://www.dr-bob.org/babble/20060108/msgs/596505.html