Where's my brain?
Are you pregnant and feeling like your brain is on
permanent hiatus? You're not alone - one researcher says that the
memory of a pregnant woman is like that of a 60-year-old. Dr
Melanie Woodfield looks into the research on 'preggy brain' and
discovers it's not all in your head.
It's known by many terms, in many countries, and it's the
bane of many a mother's existence. Whether you call it "baby
brain", "preg head", "mummy brain", "preggy brain", or "nappy
brain", losing a few of your marbles during pregnancy seems
inevitable. But is this a substantiated fact, or is it another one
of the numerous pregnancy old wives' tales? Do we really lose our
memory and have trouble concentrating, and, if we do, are there any
other abilities that are heightened to make up for it? Stay tuned
to find out. That is, if you're able to concentrate for long
enough…
Fatigue
Fatigue is worth mentioning first. A pervasive sense of tiredness
seems to hit almost from the first day of your missed period. The
tiredness is often profound, and can't be shifted by a good night's
sleep. The first and third trimesters are reported by many women to
be the worst for tiredness, although some mums-to-be suffer all the
way through. Second and subsequent pregnancies seem to bring more
tiredness with them. Whether it's the energy required for caring
for another child, or the lack of a "romantic" sense of being
pregnant to help alleviate the fatigue, there's no doubt it's an
exhausting business. And with that exhaustion comes the potential
for a collection of side-effects, affecting physical and mental
ability. Fatigue is likely to exacerbate any pre-existing memory,
attention or concentration difficulties, which is worth bearing in
mind, when you're wondering if you've lost your mind.
General ability
In 2003, RHM de Groot and colleagues decided to find a group of
women in early pregnancy (14 weeks in this case) and match them
with a group of non-pregnant women who matched as closely as
possible in key areas such as age and educational achievement. De
Groot ended up with 71 pregnant women and 57 "control" women. The
women were administered a battery of different tests focusing on
these areas: Intentional learning (deliberate learning of new
material), retrieval from semantic memory (remembering words), and
speed of information processing (how rapidly we make sense of
information). Interestingly, the researchers found statistically
significant differences between the two groups of women in the
first two aspects - pregnant women had more difficulty learning new
material and with this particular aspect of memory. There was no
difference between the groups with information processing
speed.
The authors cautioned that the memory
differences that they did find were very small, that the study
itself was rather small, and that a "longitudinal" design would
have been more appropriate to determine clear associations between
cognitive performance and pregnancy. But this study was somewhat
unique, in that it examined neuropsychological performance in the
wider sense. It seems that the majority of studies into the
cognitive performance of pregnant women have looked at memory. A
substantial number of studies have been carried out, with rather
conflicting results. We will look at these in detail in a
moment.
Memory
Memory does seem a rather relevant aspect to examine. Many
mums-to-be experience a sense of befuddlement that wasn't there
before they had children. Have you ever forgotten your best
friend's baby's name, your mother-in-law's phone number, or
completely blanked as to where you left that all-important packet
of wipes? There's no doubt that, anecdotally, our memory is not at
its best when we're pregnant or parenting young children. But is
this a true change in memory ability, or is it simply a product of
being distracted, tired, and stressed? Or, could it be both?
Julie Henry and Peter Rendell, a pair of
Australian researchers from the University of New South Wales and
the Australian Catholic University in Melbourne, respectively, have
attempted to answer this question. They pooled together all of the
studies they could find (14 studies over the past 17 years) that
had examined pregnant women's memory and had compared this with
non-pregnant women's memory. They noted that, interestingly,
pregnant women almost always describe themselves as more forgetful
than before pregnancy. For this reason, Drs Henry and Rendell were
very careful to ensure they only included studies that had formally
assessed memory, and not simply asked women to describe their own
memory ability.
What they found was very interesting.
Pregnant women's memory was definitely worse (in some areas) than
non-pregnant women, and forgetfulness continued for several months
after the baby was born. The researchers did point out that the
differences between the groups were very small. In The Observer, Dr
Henry likened the memory of a pregnant woman to that of a
non-pregnant 60-year-old. She was also quoted as saying "regular,
well-practised memory tasks are unlikely to be affected, such as
remembering phone numbers of friends and family members. However,
the ability to perform more novel memory tasks, such as having to
remember new phone numbers or people's names, or recalling five or
six digits for a short period of time, may be affected."
Henry and Rendell weren't able to draw
conclusions about why memory was impaired, but highlighted possible
influences such as hormonal changes, changes in brain chemistry,
mood changes, cultural stereotypes, and lifestyle factors. In The
Observer, Dr Henry said, "Our own suspicion is that lifestyle may
be a relevant factor to consider; for example, the increased
disruption and dislocation of pregnancy, busyness and the lack of
routine associated with this period. Sleep deprivation is also
going to be a relevant factor post-pregnancy that could affect
cognitive performance." If we're tired, we're less likely to fully
attend to a task. Our brains then process the information less
effectively, and we're therefore less likely to remember it later
on.
These results are not always supported,
however. In fact, several studies have found that pregnancy has no
effect on memory. A well designed study involving 2,500 women who
were tested repeatedly over a 10-year period showed that pregnancy
had no effect on memory at all. The study was reported in early
2009, and carried out by Professor Helen Christensen and her team
at the Australian National University in Canberra. It's worth
paying attention to these results, as the longitudinal design and
large sample size make for an authoritative study!
Another smaller study was carried out by
Dr Ros Crawley, a psychologist from the University of Sunderland,
in 2003. Dr Crawley compared 15 pregnant women with 14 matched
non-pregnant women on various measures of attention and memory. The
women were tested twice during pregnancy, and at six and 12 months
after birth. While the pregnant women rated their own memory and
attention as worse than normal, the actual performance of the
two groups was the same.
Professor Christensen and Dr Crawley had
two possible explanations for this. First, the possibility that
pregnant women's memory and attention is impaired, but that the
measures used weren't sensitive enough. The second possibility is
that mood swings are to blame (aren't they always?), or that the
women expected to have "baby brain" during pregnancy, which made
them more aware of forgetting things, and, because of this
social/cultural expectation that their memory was poor, they
attributed this normal forgetfulness to their pregnancy.
Interesting!
Even more interesting is that some
researchers have asserted that pregnancy actually makes mums
smarter! Animal research involving rats, that can be applied to
humans (believe it or not), suggests that rat mothers are better at
multi-tasking and show less fear than rats without children. Could
it be that, because we're so busy, we don't have time to dwell on
those things that make us anxious, and we have to be faster and
more efficient at what we do? This despite the difficulty we might
have in imagining a multi-tasking rat mummy talking on her mobile
phone while finding a lost sock and helping her rat son with his
homework.
Attention and concentration
Towards the end of my first pregnancy, I found it difficult to
concentrate on anything but the impending arrival of my baby.
Thankfully, apparently this is fairly common. So common, in fact,
that there's even a name for the situation - "primary maternal
preoccupation". Donald Winnicott, a paediatrician and child
psychoanalyst, first described the condition in 1956. Essentially,
the term refers to the emotional and psychological processes that
mothers undergo in order to prepare for motherhood. As this is a
hypothetical state of mind, it's rather difficult to test
empirically, but worthy of note nonetheless.
Interestingly, one researcher has
suggested that spending time in nature, or on "natural-type"
pursuits can help pregnant women's concentration. This observation
is based on one small study, which means we can't draw too many
powerful conclusions, but it seems that "spending 120 minutes each
week in restorative activities involving nature" can help with
concentration. Take a look at Mary Ann Stark's 2003 study for more
information if you're interested, preferably while sitting under a
tree.
Sense of smell
It's not talked about as often as memory loss, but another
brain-related phenomenon that occurs during pregnancy involves our
senses of taste and smell. Weirdly, we seem to become
super-sensitive to even the slightest whiff , or the most
microscopic trace of an element in our food or drink. This can be
used to our advantage, as in the case of the team of wine tasters
at Tesco supermarkets, who were reported by The Guardian newspaper
in 2004. Four of the team of wine tasters became pregnant around
the same time, and all noticed that their sense of taste and smell
had been enhanced - one of the team commented that "it's as if the
volume has been turned up on the flavours". Tesco decided to
capitalise on this experience, and ran a campaign calling for
pregnant women to join their team of wine tasters! Shocked? Don't
worry - the company emphasised that wine tasting involves spitting
the wine out, and not swallowing it.
Interestingly, there's actually some
research evidence to support the idea that our sense of smell
changes during pregnancy. Steven Nordin and his Swedish colleagues
carried out a study in 2004 that surveyed approximately 140 women
at 13-16 and 31-34 weeks of pregnancy, and 9-12 weeks after baby
was born. These results were compared with surveys completed by
non-pregnant women. The findings from this study were based on a
"self-report" measure; in other words, women reported their own
experiences, as opposed to a more "objective" measure of changes in
smell.
Despite this, the results were compelling.
Abnormal smell and/or taste sensations were reported by 76% of
pregnant women! These women mainly related this change to the
pregnancy itself. Increased sensitivity to smells was most
prominent in early pregnancy, and this was occasionally accompanied
by smell distortions and/or "phantom" smells. These differences
were less common in later pregnancy, and almost completely absent
after baby was born. 26% percent of women also described a change
in taste - typically reporting decreased salt sensitivity (needing
more salt to actually taste it), and an increased sensitivity to
bitter tastes.
So it seems that we become better
multi-taskers, more bold, and better at smelling and tasting when
we're up the duff. On the flip side, we might (or might not) have
more difficulty remembering new information and concentrating
well.
Despite the difficulty we've had in
finding a single, unanimous, authoritative study, it certainly
seems that enough women have anecdotally reported changes in their
cognitive functioning to make this area worth studying. Next time a
friend or colleague blames a slip-up on "baby brain", have some
sympathy - she's not alone.
Dr Melanie Woodfeld is a clinical psychologist in
Auckland. She can't remember any memory loss during pregnancy, but
does recall being able to smell a burger at 100 paces!
References
* Campbell, Denis. "Pregnancy does cause
memory loss." The Observer 3 February 2008.
www.guardian.co.uk/science/2008/feb/03/medicalresearch.pregnancy
* Crawley, RA. "Cognition in pregnancy and the first year
post-partum." Psychology and Psychotherapy: Theory, Research and
Practice 76 (2003): 69-84.
* Ellison, Katherine. The Mommy Brain: How Motherhood Makes us
Smarter. Basic Books (2005).
* de Groot, RHM, et al. "Memory performance, but not information
processing speed, may be reduced during early pregnancy." Journal
of Clinical and Experimental Neuropsychology 25.4 (2003):
482-88.
* Nordin, S, et al. "A longitudinal descriptive study of
self-reported abnormal smell and taste perception in pregnant
women." Chem Senses 29 (2004): 391-402.
* Stark, MA. "Restoring attention in pregnancy." Clinical Nursing
Research 12.3 (2003): 246-265.
As seen in OHbaby!
magazine Issue 9: 2010
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