Baby brain - myth or truth?

A typical evening conversation in our house:

Me: "hey I was thinking... this weekend we need to..."

(30 seconds elapse)

DH: "we need to what?"

Me: "what?"

DH: "you were saying we needed to do something this weekend"

Me: "was I?  Umm, nope it's gone, sorry."

Baby brain.  That universal phrase useful for excusing almost all forgetful/vacant behaviour both during and after pregnancy.  Some say myth, some say unfortunate reality.

As demonstrated, I continue to suffer from its common symptoms, namely:

(a)   returning items to places where they're not commonly found (muesli in fridge, yoghurt in the cupboard)

(b)  continually losing my keys

(c)   buying, but forgetting to display, a parking coupon (that was a $40 ticket!)

(d)  not keeping appointments and coffee dates

(e)   repeating the same boring story, to the same people

(f)    saying “did I tell you this already?” (this prevents (e) above)

(g)   using words and phrases like "you know", "um", "that thing over there" instead of common words

(h)  trailing off mid-sentence, with no recollection that I was even saying anything upon prompting

(i)     and saying “what were we talking about again?”

Two recent studies have looked at this so-called phenomenon.  A 2008 review concluded that pregnant women are "significantly impaired on some, but not all, measures of memory" and that these effects are also observed post-partum.  But apparently it's a modest deficit, kind of like comparing 20-year-olds with 60-year-olds.  So baby brain is just one of the little insights we get into what it's like to be old, along with a long list of other ailments that we won't go into here.

Another study, carried out in 2010, noted that the literature on animal-model studies had shown pregnancy and motherhood to have the opposite effect - with rats showing better spatial learning and memory during pregnancy and beyond, and rat mothers performing better than their baby-less counterparts at navigating mazes.  Strangely, no-one's reported seeing rat mothers cursing into their handbags looking for their car keys.

This study found that pregnancy had no effect on cognitive ability, concluding that the "results challenge the view that mothers are anything other than the intellectual peers of their contemporaries."  Phew.  

So perhaps I was this forgetful before.

What were we talking about again?