The overworked, overcrowded middle-aged mind can be forgiven a few memory lapses.
The overworked, overcrowded middle-aged mind can be forgiven a few memory lapses.


Is it possible, from a scientific point of
view, that NSW former premier Barry O'Farrell had a "senior's moment"
when he forgot about the $3000 bottle of wine he received as a gift?
Kind of.

At 54, O'Farrell is deep into middle age, according to a
2012 study published in the British Medical Journal that found cognitive
decline begins at about 45, not at 60 as it was once thought. Already
O'Farrell is experiencing some level of age-related memory loss and a
slowing of his reasoning processes.

Further, memory loss is
exacerbated by stress. As Harvard Medical School's neuroscience
newsletter, On The Brain, noted last year in an article on the
middle-aged brain, the hormone cortisol – released during the
"fight-or-flight" response to stress – can prevent the brain from laying
down new memories or from accessing existing ones. Worse, it can damage
the hippocampus, the part of the brain most associated with memory
storage.

"Excess cortisol can make it difficult to respond to
stimuli or retrieve the stored memories needed to guide us in certain
situations, a condition that may account for our being bewildered when
stressful situations arise," the newsletter reads.

Well, who wouldn't want to flee the spotlight of a corruption
inquiry? So let's leave O'Farrell with that comforting thought and shine
a light on all middle-aged folk, the multiple fronts where their lives
have become a form of combat, including the nagging worry that they are
losing their minds.

Who doesn't want to flee reality when your
teens are carrying on like emperors, your ageing parents are on the
phone again with a fresh crisis, your divorce is in train, your job may
not survive the next round of redundancies, your doctor is rabbiting on
about diabetes, your prostate, your lower bowel, your weight, your eyes
are demanding glasses, and . . . well, where are the bloody car keys so I
can get the hell out?

The overworked, overcrowded middle-aged
mind can be forgiven a few memory lapses. So take a breath and tell
yourself: "Damned cortisol, that's all it it is." Except it's not.

While
it can be galling to realise you can't run or lift heavy objects with
the ease you knew as a 20-year-old, it's frightening when you walk from
one room to another, full of purpose, only to find yourself standing
without a clue as to what task you were in the middle of. Especially if
only the other day you left your keys in the front door. And so on.

There
was a time you'd laugh it off. Now, in your 40s and 50s, there's a
worry that these lapses are the first signs of dementia, that you're one
day too soon going to look in the mirror and wonder who that is.

Dementia
– and, of course, the dark lord of dementia, Alzheimer's – reached
epidemic proportions in Australia five years ago, according to an Access
Economics study, commissioned by Alzheimer's Australia.

Last
year, the Facing the Health of Australians survey of 5000 people aged
32-55, commissioned by the Australian Medicines Industry, found dementia
was second only to cancer as our greatest health concern, more feared
than diabetes, obesity or depression. An estimated 280,000 people have
dementia in Australia. That number is expected to double by 2030 and
reach almost one million by 2050.

In other words, for ageing baby
boomers and gen Xers, the epidemic riddling their parents' generation
today looms as their own plague of tomorrow. And maybe, recalling when
you forgot why you came into a room, it's happening now.

Professor
Peter Schofield, executive director of Neuroscience Research Australia,
(NeuRA), says the fear that middle-aged people harbour about dementia
isn't unreasonable. "It's true that age is the biggest single
contributor," but the fear is overblown, he says.

"Yes, as we age
our brains shrink. Yes, they slow down a bit. We begin to lose neurons
and they aren't replaced at the rate they once were. And so in some
measure we are not as sharp or quick as we once were. But in the vast
majority of people in their 40s, 50s and 60s, that lack of sharpness is
more a function of the complexity of what their brains are dealing with .
. . it's more a matter of selective attention than a measure of
clinical pathology."

But because dementia is a high-profile issue,
"many people are much more anxious about it. Every time they can't find
their keys is an impending sign of dementia. Losing your keys is an
anxiety issue, not a cognitive one."

Schofield says people
"attribute too much to middle age" as a time of mental decline. "It's
when you're 70 and 80 years old having a senior moment that you're more
likely experiencing mild cognitive impairment. Even then, generally,
it's not enough to be lifestyle-disabling."

Kristyn Bates,
research assistant professor in experimental and regenerative
neuroscience at the University of Western Australia, says the prevalence
of middle-aged and older people scaring themselves into wrongly
thinking they're losing their minds is so high it has led to the
creation of a new area of research – "subjective memory complaint".

"There
is nothing wrong with their memory that we can measure. They perform
normally. Because it's poorly defined, the prevalence of subjective
memory complaint is between 20 to 50 per cent of the elderly
population," says Bates.

The key issue here is that the healthily
ageing brain doesn't lose memories, they just take longer to retrieve.
As Marshall Dalton, a former research assistant at NeuRA, notes in a
blog written in part as a response to frequently asked questions,
"age-related memory problems are the result of reduced efficiency in
communication between brain cells, whereas memory problems in dementia
are the result of cell death".

In many instances when our brain
seems to be malfunctioning, it's actually taking charge. In that moment
when you walk into a room and forget what brought you there, Schofield
advises: "Perhaps the task was displaced by a more interesting thought
or event. When you forget what you were doing, it's possibly because it
wasn't so compelling. Most of us don't have hugely long attention
spans."

One of Schofield's's research interests is the genetics of
brain function. One of those functions is the ordering of information,
and giving priority to certain thoughts and events over others. This
includes everything that we consciously see that's going on in the world
– our eyes being a physical extension of the brain. The brain takes it
all in, both focusing and editing what's happening in front of us.

This
leads us to the unnerving issue of false memories – some researchers
argue that every long-term memory we have is in some way false. This is
because memory is a reconstruction, not a video recollection. When a new
memory is acquired it goes through several different processes, firstly
at the synaptic level (the junction where information is passed from
one nerve cell to another), which takes hours; and then in the
hippocampus, the part of the brain where new memories are laid down.

Each
time we drag up a memory, it's been altered in some small way because
of the circumstances we're in at the time, because of the motivation for
recalling it or because new information has somehow mixed in with the
original event. Why? It's thought largely to be a function of
adaptation, and the brain being efficient.

The net effect is that memories, unless they have been planted by suggestion, are true enough.

Schofield
says it could be that memories are moved from one part of the brain to
another, like a filing system being shuffled. "The things you think
about more are replayed more often. But there's a huge subjective
element . . . in often replaying the memory, you form false
recollections."

Last year, researchers from the Massachusetts
Institute of Technology successfully planted false memories in mice.
This was hailed as having great potential for treating sufferers of
post-traumatic stress disorder, where bad memories could be edited into
happier ones.

There are studies that show older adults are
sometimes more likely than younger adults to remember events that never
happened, but this may be a self-protective mechanism. A University of
Virginia study from 2005, "With Sadness Comes Accuracy; With Happiness,
False Memory", found happiness tends to generate false memories, while
unhappiness dredges misery.

This isn't to say false memories
generate the greater happiness and contentment that people 50 and over
are routinely said to experience, but they may be both an expression and
reinforcement of that happiness.

The On The Brain newsletter
reported a study that found the middle-aged brain screens out negative
emotions when confronted with negative images and is otherwise wired to
accentuate the positive. It also noted that the brain in middle age may
be more resilient that at any other time in life.

In fact, there is growing evidence that the middle-aged brain is more of a good-news story than a sad one.

Bates,
of the University of Western Australia, says when she was an honours
student in 2000, it was still thought the brain stopped producing
neurons past childhood. "We now know that isn't true. Evidence came out
last year that the hippocampi [we have a hippocampus in each hemisphere]
each makes 700 new neurons every day."

She says that while
middle-aged brains begin to lose synapses and there is an associated
slowing of some functions, it's now understood that "in middle age
people use their brain differently. Both sides of the brain are used to
process information, rather than just the one side".

It's not yet
understood if this is a natural offset to lost function, but the net
result is better communication between both halves, and a greater
ability to better judge situations and evaluate information. "What we're
seeing is the biological basis for wisdom that comes with ageing."

The
best news is that the decline of the brain can be slowed – even
repaired – by doing the same things that keep our hearts healthy –
exercise, good diet, manage stress. The best exercise seems to be
education.

Says Bates: "There's a dogma in neuroscience – the cells that fire together, wire together."

In layman-speak? Use it or lose it.