Mind Hacks™: Tips & Tools for Using Your Brain (41 page)

Hack memory to make people feel they’ve seen something before.

Try this teasing task, using stimuli from Whittlesea and Williams’ 1998 study.
¹
Or better yet find a volunteer to tax instead. Look at the words in
Table 9-1
, one at a time
(around 2–3 seconds a word), in both columns. Then take a breather for a minute or
two.

Now turn to the second list of words,
Table 9-6
, at the very end of this chapter.
Go through the second list and check/tick with a pencil those that feel familiar (if you
like, you can put a cross by those you definitely didn’t see).

What did you experience? Most people find that while the real words were easy to
identify one way or another, certain of the nonwords had a creeping feeling of
familiarity. Possibly you checked/ticked some that, in fact, you hadn’t seen. If so, your
recognition memory has just been royally messed with.

This test is a good way to bring out the heuristic, fast-and-loose nature of
recognition memory. When we encounter something we have experienced before, familiarity
can hit us extremely rapidly. This feeling need not be accompanied by extensive memory
information, which shows it isn’t due to deep memory retrieval. Instead, recognition
memory seems to be piggybacking on the rapid incoming sensory information to flood us with
this sense of “having seen.” What qualities of perception might be useful? Well, as seen
before, items that have been seen recently are processed faster and more easily
[
Bring Stuff to the Front of Your Mind
]
— we
can call this
fluent processing
, or just
fluency
. The level of fluency you experience when you encounter
something should be an ideal source of information for recognition memory; if you feel
fluent in something, it’s a good sign you’ve seen it before. But there’s a problem.

Consider catching sight of your partner as you enter your home after work versus the
situation in which you catch sight of a less familiar figure in an incongruous situation
(say, your boss at a nightclub). The flash of familiarity comes in only the second
situation, even though the first is far more
common. So it turns out the fluency system is a little bit smarter. It needs
to be, or we would spend our waking life overwhelmed by the familiarity of every
experienced object in our environment. Other mechanisms are brought in to compensate for
the high level of fluency associated with regularly encountered experiences. For example,
words are processed extremely fluently, due to our dedicated language systems
[
Speech Is Broadband Input to Your Head
]
, and
so the mind usually takes this extra fluency into account when presented with meaningful
verbal items.

The complication in word lists like the ones in the tables is that there is no clear
division between word things and certain of the nonwordlike things, the ones you felt
you’d seen before. These nonwords are meaningless yet nonetheless have the structure of
words and therefore feed into the mind as easily as they trip off the tongue, becoming
more fluent than nonwords ought to be. This discrepancy — a “surprising fluency,” as
Whittlesea puts it — fools your brain into concluding you’ve seen the nonwords before. The
effect extends to music, with famous tunes, well-structured (catchy) and ill-structured
(less musical) novel tones. The brain takes a measure of its own speed of processing
(fluency) and uses
that
to produce smart and fast information about
the environment — in this case, whether the specific experience has been had before.
Well-structured tunes get falsely tagged as already heard much more than the others,
because they have more fluency.

This kind of memory illusion serves advertisers well in their search for ways to get
products in with the public: word-like product names are not only easier to repeat, but
feel more familiar the first time around, as can musical jingles and catchphrases. Bearing
in mind the slight, but real effect that mere exposure
[
Subliminal Messages Are Weak and Simple
]
can have, this makes
fluency a design ambition. It could have more serious ramifications when it comes to the
law, as the process of
identifying criminals can involve amplification of ambiguous feelings, such as
“I’ve seen you before — but where?” Such feelings could be produced by preexposure to a
suspect among hundreds of mug shots before a lineup or a glimpse of the subject’s face in
a mug shot book before the ID session has officially begun.

But we must recognize that these highlighted errors reflect a fundamental process, one
essential to our day-to-day behavior, as fluent processing flips us into familiarity mode
only when something in the environment falls out of line with expectations. It’s a handy
hack, using “norms on the fly,” as Whittlesea puts it.
¹

There is an ongoing debate about the localization of mechanisms upon which familiarity
responses depend, with the parahippocampal gyrus (part of the limbic system
[
Get Acquainted with the Central Nervous System
]
,
adjacent to the hippocampus in the temporal lobe) being touted as a candidate region. It
is clear that, relative to the healthy brain, damage to temporal lobe regions impair both
recognition and recall memory, but there is conflict over whether these amnesiac patients
are more prone to these memory errors or actually less; this is becoming a topic of
considerable interest in neuroscience.

Familiarity could be considered the cognitive equivalent of sensory pop-out (just like
flat shapes that pop out into 3D using shading to emulate shadows
[
Fool Yourself into Seeing 3D
]
), but our brain makes
sure these things pop out only when they tend to be useful, harnessing higher-level
expectations and lower-level rules of thumb to home in on the interesting features of our
environment.

— Alex Fradera

When memory serves up information upon request, it seems to come packaged with
its origin and sender. But these details are often produced ad hoc and may not fully match
the true source.

This test involves word stems, the idea being to complete the beginning of each stem
in
Table 9-2
with a word of your choice.
So
ple___
(complete it with any number of letters) could be “please,”
or equally “pledge,” “pleat,” and so on. Complete the odd-numbered stems (the ones on the
left) out loud; for the even-numbered ones (on the right), merely
imagine
saying the words. Use a different word for each stem (i.e.,
don’t use “please” twice if you run across the
ple___
stem
twice).

Now see if you remember your two
fla__
words (it should be fairly
easy) and whether they were spoken or imagined. You’ve got a fair chance of being
right, although you’d likely make a few slips across the whole list. Try the
whole list if you like, giving both items and whether you said them out loud or in your
head:
bre__
,
spe__
,
sal__
,
tar__
,
mon__
, and
fla__
.
It’s probable that you can remember what you said for most words, and usually whether it
was spoken or imagined. But while this is not an impossible task, you are in no way
guaranteed to get the source of a recalled item correct.

Now in the traditional view of the mind, the idea that memories could stray from their
true context — that there is no master index putting all our memories in their place — is
rather troublesome. On the other hand, consider what was done: when you come to look back,
you have memories that are in most respects equivalent — for both spoken and imagined
answers, you are left with a purely mental record of you saying the word. At the time,
saying the word out loud was different from just imagining it, but now all that remains of
both events is just an internal image of you saying the word. Yet, somehow, for the most
part, we can distinguish the real event from the imaginary kind. That you’ve done it at
all seems a testament to the memory system, as there are no obvious hooks to pull apart
the problem.

Let’s dig a bit deeper into this...

If memories were items — whole events that were fed into memory from an ideal memory
system — it would be odd for us to retrieve a detail stripped of context. In the previous
task, this would be knowing a word but not knowing if it were really said; but other
mistakes taken from research include confusing the gender of the voice that spoke a word,
or whether information was presented in the lab, learned outside it, or given in an audio
or visual modality. The fact that we can make these errors pushes us to accept that
memories are not holistic (read: nicely packaged) entities. Given further consideration,
it is hard to imagine how they could be so and still be useful.

Consider this: how could you (or your brain) objectively and instantly demarcate the
boundaries of what constitutes a single event? An event is as long as a piece of string,
just as an “item” is as many features as you need to make that item. Figuring out what an
“event” or “item” is, is an implausible task. If the brain were to attempt it, we would be
stuck halfway to nowhere.

Once we reject this view and, in so doing, are freed to look at memories as
collections of features, we can again wonder how it is that we can reconnect a memory
detail with its source. This is a property memory needs to function well, so it should
come as no surprise that the brain has found a solution. This is the use of multiple
processes (parallel processing is a common pattern
[
Robust Processing Using Parallelism
]
): one to allow quick
automated categorization, coupled with a fact-checker to catch any major glitches and
inconsistencies.

The quick system is a “heuristic” route, which relies on generalities about
the mental world to make snap classifications. So, for example, there is usually a greater
degree of perceptual and contextual information in
perceived
events
relative to
imagined
events. Imagined images are probably sparser in
content and richness of detail, so a memory that is full of detail and vividness can be
quickly categorized as a good candidate for being a real memory. Even when the situations
seem identical, there are subtle differences in memory quality that may be exploited; we
can make comparisons in different modalities (audio/visual) to exploit different, but
analogous, perceptual and contextual discrepancies.

Great examples of source confusion abound. The pioneer neurologist Charcot’s patient
LeLog was convinced his paralysis was due to his legs being crushed in a traffic accident,
yet this injury had never occurred and, in fact, his paralysis had no physical basis.
LeLog had mentally rehearsed this situation to the extent that it began to obtain the
flavor of reality, leading Charcot to coin the notion that the mind may be parasitized by
suggested ideas. A less extreme outcome of source confusion in the healthy mind is
unconscious plagiarism.
^1
,
2
This is the consequence of being presented
with an idea, usually in a situation in which the ownership may not be explicit or
emphasized (brainstorming in a group or hearing a ditty on the radio without any clear
sense of the artist), and consequently believing the idea is genuinely your own. Often the
individual will rehearse and revisit the idea, and this can demolish its association with
an external source or speaker. These errors can lead to merry legal escapades, especially
as the accused will be unwilling to back down even in the face of incontrovertible
evidence, due to the certainty we have in our own memory. Even Mark Twain, that most
individual and independent-minded writer, fell foul of this.
³
The same effect may lead to rather less costly squabbles, as evidenced by
studies that show identical twins can dispute the possession of certain memories
⁴
; the degree of shared existence and confidences in these situations can
lead to the real identity of memory protagonists being blurred.

When we turn to the abnormal functioning of the memory system, we are faced
with a far more extreme example, that of patients who display confabulations.
⁵
These individuals will give fanciful, false responses to questions in
totally good faith, mixing details from films, current affairs, or their distant past into
statements about their current activities. These individuals can be otherwise functioning
fairly normally, and rationally intact, even embarrassed by inconsistencies in the
memories they express, but will insist that this is what their minds are offering them.
Often information that has been recently presented will be regurgitated as distinctive
personal experience, the source dislocated from the item itself.

The reason that we, unlike these patients, rarely produce phantoms of this magnitude
is believed to be due to a stellar monitoring and assessment system distributed within the
frontal lobes of the brain. It sifts through mental items and labels them correctly as
fantasy, fact, or nonsense or warns us that we do not have enough certainty to say either
way. We may occasionally forget whether we were intending to turn the oven off or actually
did so, but it is rare indeed that we will find ourselves confusing an intention to
complete an information-rich task (say, going to visit a relative) with actually having
done so.

These systems seem to be at fault within these confabulators, which, in combination
with deep memory deficits, allows the creative elements of the mind to weave stories out
of piecemeal elements. Confabulations seem to require damage to the two systems together:
a severe problem with memory coupled with the lifting of the monitoring systems that
prevent flights of fancy and other intact but irrelevant memories being crowned with the
status of authenticity.

— Alex Fradera