Mind Hacks: Tips and Tools for Using Your Brain - Tom Stafford

Mind Hacks begins your exploration of the mind with a look inside the brain itself, using hacks such as "Transcranial Magnetic Stimulation: Turn On and Off Bits of the Brain" and "Tour the Cortex and the Four Lobes." Also among the 100 hacks in this book, you''''ll find: Release Eye Fixations for Faster Reactions See Movement When All is Still Feel the Presence and Loss of Attention Detect Sounds on the Margins of Certainty Mold Your Body Schema Test Your Handedness See a Person in Moving Lights Make Events Understandable as Cause-and-Effect Boost Memory by Using Context Understand Detail and the Limits of Attention

Mind Hacks™: Tips & Tools for Using Your

Brain Tom Stafford

Matt Webb

Published by O’Reilly Media

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Few developments in the brain sciences over thepast 20 years have been as crucial as the steadyeradication of the brain-as-computer metaphor thatdominated so much of our thinking about thinking

in the ’60s and ’70s Partly the metaphor declinedbecause artificial intelligence turned out to be avastly more complicated affair than we imagined;partly it declined because we developed new toolsfor understanding and visualizing the biology of thebrain, which didn’t look like a microprocessorafter all; partly it declined because an influentialgroup of scientists began exploring the vital role ofemotion in brain function It’s true the brain

contains elements that resemble logic gates ofdigital computing, and some influential researcherscontinue to describe the activity of mind as a kind

of computation But for the most part, we nowaccept the premise that computers and brains aretwo very different things that happen to share someaptitudes: playing chess, say, or correcting

At first glance, the book you’re holding in yourhand might be accused of reviving the old brain-as-computer conceit: “hacks” is a software term,after all, and the previous books in the series haveall revolved around digital computing in one form

or another But I think this book belongs instead to

a distinctly 21st-century way of thinking about thebrain, one we might call—in the language of

software design—user-centric The wonders of

brain science are no longer something we

contemplate exclusively in the lab or the lecturehall; we now explore how the brain works bydoing experiments on our own heads You canexplore the architecture and design of your brainjust by sampling the many exercises included in thefollowing pages Consciousness exploration is anold story, of course—one of the oldest—butconsciousness exploration with empirical science

as your guide is a new one We’ve had the age ofFreud, of psychedelics, of meditation This booksuggests that a new form of introspection is on therise, what I’ve called, in another context,

“recreational neuroscience.”

I think the idea of a brain hack is a wonderful one,and Matt Webb and Tom Stafford have assembledhere a collection of tricks-of-the-mind that willastound you, and give you a new appreciation forthe way your brain shapes the reality you perceive.But it’s worth pointing out a subtle distinctionbetween the software use of the word “hack” andthe way Matt and Tom use it here In programming,

a hack is something we do to an existing tool thatgives it some new aptitude that was not part of itsoriginal feature set When we hack a piece of code,

we are bending the software to fit our will; we’remaking it do something its original creators neverdreamed of

The mind hacks that will delight and puzzle you inthe coming pages largely work in the oppositedirection When you undergo these experiments,what you’re sensing is not your brain’s

subservience to your will, but rather its weirdautonomy These hacks amaze because they revealthe brain’s hidden logic; they shed light on the

cheats and shortcuts and latent assumptions ourbrains make about the world Most of the time,these mechanisms are invisible to us—or so

ubiquitous we no longer notice their existence Abrain hack is a way of pulling back the curtain ofconsciousness to glimpse—however fleetingly—the machinery on the other side

This can be a profoundly unsettling experience,precisely because it reveals the way the brain isnot always subservient to your will, which veryquickly leads you down an existential slide

(Whose will is it anyway?) But it’s a journey thatanyone interested in the mind cannot afford to miss.Our brains have a kind of life of their own, quiteapart from what we think we know about

ourselves That’s a scary thought, but being scarydoesn’t make it any less true As you read throughthe coming pages, you’ll no doubt find yourselfalarmed at the strange cognitive behavior you cantrigger just by following a simple set of

instructions But I suspect you’ll also find yourselfwith a new sense of wonder about the mystery ofconsciousness—along with some killer cocktail

party tricks.

So that is the inward adventure that lies beforeyou May it mess with your head in all the rightways

—Steven Johnson Brooklyn, New York

Steven Johnson is the author of Mind Wide Open:

Your Brain and the Neuroscience of Everyday Life (Scribner).

About the Authors

Tom Stafford likes finding things out and writingthings down Several years of doing this in theDepartment of Psychology at the University ofSheffield resulted in a Ph.D Now sometimes hetells people he’s a computational cognitive

neuroscientist and then talks excitedly about neuralnetworks Lately he’s begun talking excitedly aboutsocial networks too As well as doing academicresearch, he has worked freelance, writing andworking at the BBC as a documentary researcher.Things he finds interesting he puts on his web site

at http://www.idiolect.org.uk

Matt Webb is an engineer and designer, splittinghis working life between R&D with BBC Radio &Music Interactive and freelance projects in thesocial software world In the past, he’s madecollaborative online toys, written IM bots, and run

a fiction web site (archived at

http://iam.upsideclown.com ); now he’s content

with hacky web scripts and his weblog,

Interconnected, at http://interconnected.org/home

Matt reads a little too much, likes the word

“cyberspace,” lives in London, and tells his motherhe’s “in computers.”

Contributors

The following people contributed to this book:

Adrian Hon ( http://mssv.net ) graduated from

the University of Cambridge with a degree innatural sciences, specialising in neuroscience

He has also researched synaesthesia with Prof

V S Ramachandran at the University of

California, San Diego, and spent a year at theUniversity of Oxford researching integrativephysiology In the past few years, Adrian hasbeen the cocreator of the NASA award-winningweb site Astrobiology: The Living Universeand has spent 2 weeks in the Utah desert in asimulation of a manned mission to Mars (duringwhich time he realised a long-held ambition of

wearing a spacesuit) More recently, Adrianhas developed a serious interest in alternatereality games and is currently working onPerplex City.

Alex Fradera (

http://farmerversusfox.blogspot.com ) is a

psychology grad student at University CollegeLondon He likes to make science seem like fun,but all too often fun seems like science Nomatter When not testing patients or writingprograms, he may be found fronting his band,reading comics, or playing capoeira

Andy Brown is currently reading for a Ph.D indevelopmental cognitive neuropsychology at theUniversity of Sheffield He has an M.Phil inpsychology (looking at cognitive impairmentfollowing stroke) and has also spent 2 years as

a research assistant at University CollegeLondon looking at computer-based

interventions within primary care clinicalpsychology He is also a photographer (

http://www.envioustime.co.uk ).

Chris Bird (http://www.icn.ucl.ac.uk ) is a

researcher at the Institute of Cognitive

Neuroscience in London He investigates theeffects of brain damage on cognition

Dr Christian Beresford Jarrett (

http://www.psychologywriter.org.uk/ ) is

writer/editor of the British Psychological

Society’s Research Digest (

http://www.bps.org.uk/publications/rd.cfm ),

research associate with the sensorimotorneuroscience group at the University of

Manchester, and freelance editor for Trends in

Cognitive Sciences He lives in West

Dylan Evans ( http://www.dylan.org.uk ) is the

author of several popular science books,

including Emotion: The Science of Sentiment (Oxford University Press) and Placebo: The

Belief Effect (HarperCollins) After receiving

his Ph.D in philosophy from the London School

of Economics, he did postdoctoral research inphilosophy at Kings College London and inrobotics at the University of Bath before

moving to the University of the West of

England, where he is currently senior lecturer

in intelligent autonomous systems

Ellen Poliakoff (

http://www.psych-sci.manchester.ac.uk/staff/EllenPoliakoff ) is

a lecturer in psychology at the University ofManchester and enjoys working somewherebetween psychology and neuroscience In herfree time, she enjoys, among other things,visiting stone circles and playing in a band (

http://www.stray-light.co.uk ).

Iain Price ( http://www.iain-price.com )

studied the neurosciences for his bachelor anddoctorate degrees at Cardiff University He is

now pursuing science communication projects

in conjunction with his continued fascinationwith the philosophies of the human mind

Recently he has helped to develop and presentthe BBC’s community outreach events to

accompany The Human Mind TV series (

http://www.open2.net/humanmind ).

Karen Bunday ( k.bunday@imperial.ac.uk ) is

studying for a Ph.D in movement and balance atImperial College London, having alreadygraduated with a B.Sc in psychology fromRoyal Holloway, University of London She hasbeen published as a coauthor in the journal

Current Biology and is currently writing two

papers based on her own Ph.D research forfuture publication

married and has three children Professionally,

he provides electrodiagnostic services forpatients with eye diseases, and is interested inbasic and applied vision research, thus

covering both physiology and pathophysiology

of visual perception His hobbies includereading, swimming, programming opticalillusions, riding his recumbent bike, and inwinter snowboarding or skiing His web sitedemonstrates and explains many interestingoptical illusions and visual phenomena (

http://www.michaelbach.de/ot/index.html ).

Mike Bywaters

Myles Jones is a lecturer in psychology at theUniversity of Sheffield (

http://www.shef.ac.uk/spinsn/ ) His main

research interest is understanding the

relationship between neuroimaging signals andthe underlying neural activity

Nicol Spencer Harper is a CoMPLEX Ph.D.student in the physiology department of

University College London His main interest is

neural coding in the auditory system—how theelectrochemical impulses in our brain representsounds in the world His other interests includeeating and sleeping.

Dr Sarah-Jayne Blakemore is a Royal SocietyResearch Fellow at the Institute of CognitiveNeuroscience at University College London.Her current research focuses on the brainmechanisms underlying social interaction inautism and the development of social

understanding during adolescence She readexperimental psychology at Oxford and thenwent on to complete a Ph.D in neuroscience atUCL in 2000 She frequently gives talks aboutthe brain in schools, writes articles about herresearch in newspapers, and gives interviews

on the television and radio

Suparna Choudhury is studying cognitivedevelopment during adolescence for her Ph.D.research at the Institute of Child Health,

University College London, having completed aB.Sc in neuroscience Her research focuses on

the development of perspective-taking andmotor imagery She is also interested in

phenomenology and philosophy of mind and isinvolved in public understanding of science.Vaughan Bell is a clinical and research

psychologist interested in understanding braininjury, mental distress and psychologicalimpairment He’s currently at the Departmento

de Psiquiatra in the Universidad de Antioquiaand the Hospital Universitario San Vicente dePal, in Medelln, Colombia, where he’s avisiting professor He’s also a visiting researchfellow at the Department of Clinical

Neuroscience at the Institute of Psychiatry,King’s College London (

http://www.iop.kcl.ac.uk/staff/?go=10947 )

William Bardel ( http://www.bardel.info ) is

an information designer living in the UnitedStates, specializing in information graphics,mapping/ wayfinding, and design strategy Hiswork involves making complex ideas simpleand accessible through structure Will holds a

master of design degree in the fields of

communication planning and information designfrom Carnegie Mellon University, and a B.A inEnglish from Kenyon College; he has studiedinformation design at the Rhode Island School

of Design SIGDS

Acknowledgments

We would like to thank all those who contributedtheir ideas, hacks, expertise, and time to this book

To all those who share their research and

demonstrations online: you’re doing a wonderfulthing

Rael Dornfest has been our editor and guide.We’ve traveled a long way, and we wouldn’t havecome even close to this point without him or,indeed, without the rest of the O’Reilly team.Thanks all

Our technical editors and advisors have beenabsolute stars Thanks for watching out for us And

of course, James Cronin, who, in Helsinki,

provided both the wine and conversation necessary

to conceive this book

Many thanks to the BBC for being flexible andemploying us both (in different capacities) part-time over the past few months Thanks also to ourcolleagues and friends there and for Radio 4.Amongst the many applications we’ve used,

throughout planning, researching, and writing, the

MoinMoin Python WikiClone ( http://moinmo.in/ )

has been the most valuable

Oh, we must acknowledge the role of tea So muchtea Possibly too much, it has to be said

Tom

Matt was the best coauthor I could imagine having

—thanks for getting me on board and for seeing usthrough It’s been both an education and great fun.I’d like to thank all my lecturers, friends, andcolleagues in the department of psychology at theUniversity of Sheffield It was there that I acquired

an appreciation of just what a good account of

mind might be, and how exciting the endeavor toprovide it is.

I couldn’t have made it without my family andfriends—old, new, nearby, and far away I amastoundingly grateful to everyone who took me out,shared time with me, fed and watered me,

sheltered me, and was kind enough to indulge myoccasionally overexcited blather I have too muchgratitude to be able to list names individually, butI’m sure you all know who you are

Special thanks to my brother Jon, to Nicol whowas always there and who always understood, and

to Dan and Gemma who have been taking me out toplay while I’ve been in London and who are bothinspirational in their own way

Matt

When I’ve read the effusive thanks and apologiesauthors give to their loved ones, I must admit I’vethought it a little overdone It turns out it’s not.Thank you, Ehsan

Second, if you get a chance to go for a drink withTom, don’t turn it down Our weekly breakfastmeetings over the summer have been mind-blowing.

For the record, my last point, the surface of my

light cone is enveloping the star system p Eridani

in the hours I write these words p Eridani, hello!

Think for a moment about all that’s happeningwhile you read this text: how your eyes move tocenter themselves on the words, how you idlyscratch your arm while you’re thinking, the

attention-grabbing movements, noises, and otherdistractions you’re filtering out How does all thiswork? As one brain speaking to another, here’s asecret: it isn’t easy

The brain is a fearsomely complex processing environment Take the processinginvolved in seeing, for instance One of the tasksinvolved in seeing is detecting the motion in everytiny portion of vision, in such and such a directionand at such and such a speed, and representing that

information-in the brainformation-in But another task is seeinformation-ing a face information-in thelight that falls on the retina, figuring out whatemotion it’s showing, and representing that concept

in the brain, somehow, too

To an extent, the brain is modular, so that should

give us a way in, but it’s not that clean-cut Theprocessing subsystems of the brain are layered ontop of one another, but their functionality minglesrather than being organized in a distinct

progression Often the same task is performed inmany different places, in many different ways It’snot a clear mechanical system like clockwork orlike a computer program; giving the same inputwon’t always give the same output Automatic andvoluntary actions are highly meshed, often

inextricable Parts of vision that appear fullyisolated from conscious experience suddenlyreport different results if conscious expectationschange

The information transformations in the brain aremade yet more complicated by the constraints ofhistory, computation, and architecture

Development over evolutionary time has made ithard for the brain to backtrack; the structure of thebrain must reflect its growth and repurposing.Computation has to occur as fast as possible—we’re talking subsecond responses—but there arelimits on the speed at which information can travel

between physical parts of the brain These are allconstraints to be worked with.

All of which leaves us with one question: how can

we possibly start to understand what’s going on?Cognitive neuroscience is the study of the brainbiology behind our mental functions It is a

collection of methods (like brain scanning andcomputational modeling) combined with a way oflooking at psychological phenomena and

discovering where, why, and how the brain makesthem happen It is neither classic neuroscience—alow-level tour of the biology of the brain—nor is itwhat many people think of as psychology—ametaphorical exploration of human inner life;rather, it’s a view of the mind that looks at thefundamental elements and rules, acting moment bymoment, that makes up conscious experience andaction

By focusing both on the biological substrate and onthe high-level phenomenon of consciousness, wecan pick apart the knot of the brain This pickingapart is why you don’t need to be a cognitive

neuroscientist to reap the fruit of the field.

This book is a collection of probes into the

moment-by-moment works of the brain It’s not atextbook—more of a buffet, really Each hack isone probe into the operation of the brain, one smalldemonstration By seeing how the brain responds,

we pick up traces of the structures present and thedesign decision made, learning a little bit moreabout how the brain is put together

Simultaneously we’ve tried to show how thereisn’t a separation between the voluntary “me”feeling of the mind and the automatic nature of thebrain—the division between voluntary and

automatic behavior is more of an ebb and flow,and we wield our cognitive abilities with

unconscious flourishes and deliberate movementsmuch as we wield, say, our hands, or a pen, or alathe

In a sense, we’re trying to understand the

capabilities that underpin the mind Say we

understand to what extent the holes in our visionare continually covered up or what sounds and

lights will—without a doubt—grab our attention(and also what won’t): we’ll be able to designbetter tools, and create better interfaces that workwith the grain of our mental architecture and notagainst it We’ll be able to understand ourselves alittle better; know a little more, in a very realsense, about what makes us tick.

Plus it’s fun That’s the key Cognitive

neuroscience is a fairly new discipline Thejourney into the brain is newly available and anenjoyable ride The effects we’ll see are realenough, but the explanations of why they occur arestill being debated We’re taking part in the

mapping of this new territory just by playing along.Over the course of writing this book, we’ve spenttime noticing our own attention systems dartingabout the room, seen ourselves catching gesturesfrom people we’ve been talking to, and playedgames with the color of traffic and peripheralvision That’s the fun bit But we’ve also beengripped by the arguments in the scientific literatureand have had new insights into facets of our

everyday lives, such as why some web sites are

annoying and certain others are particularly made If, through this book, we’ve managed tomake that world a little more accessible too, thenwe’ve succeeded And when you’ve had a lookaround and found new ways to apply these ideasand, yes, new topics we’ve not touched on, please

well-do let us know We’re here for the ride too

Why Mind Hacks?

The term “hacking” has a bad reputation in the

media They use it to refer to those who break intosystems or wreak havoc with computers as theirweapons Among people who write code, though,

the term “hack” refers to a “quick-and-dirty”

solution to a problem, or a clever way to get

something done And the term “hacker” is taken

very much as a compliment, referring to someone

as being “creative,” having the technical chops to

get things done The Hacks series is an attempt toreclaim the word, document the good ways peopleare hacking, and pass the hacker ethic of creativeparticipation on to the uninitiated Seeing how

others approach systems and problems is often thequickest way to learn about a new technology.The brain, like all hidden systems, is prime

territory for curious hackers Thanks to relativelyrecent developments in cognitive neuroscience,we’re able to satisfy a little of that curiosity,making educated explanations for psychologicaleffects rather than just pointing those effects out,throwing light on the internal workings of thebrain

Some of the hacks in this collection document theneat tricks the brain has used to get the job done.Looking at the brain from the outside like this, it’shard not to be impressed at the way it works Otherhacks point to quirks of our own minds that we canexploit in unexpected ways, and that’s all part oflearning our way round the wrinkles in this newlyexposed technology

Mind Hacks is for people who want to know a bit

more about what’s going on inside their own headsand for people who are going to assemble thehacks in new ways, playing with the interface

between ourselves and the world It’s wonderfullyeasy to get involved We’ve all got brains, afterall.

How to Use This Book

You can read this book from cover to cover if youlike, but each hack stands on its own, so feel free

to browse and jump to the different sections thatinterest you most If there’s a prerequisite you need

to know, a cross-reference will guide you to theright hack

We’ve tried out all the demonstrations in this book,

so we know that for most people they work just as

we say they do; these are real phenomena Indeed,some are surprising, and we didn’t believe they’dwork until we tried them ourselves The

explanations are summaries of the current state ofknowledge—often snapshots of debates in

progress Keep an open mind about these There’salways the chance future research will cause us torevise our understanding

Often, because there is so much research on eachtopic, we have linked to web sites, books, andacademic papers to find out more Follow these

up They’re fantastic places to explore the widerstory behind each hack, and will take you to

interesting places and appear interesting

connections

With regard to academic papers, these are bedrock

of scientific knowledge They can be hard to getand hard to understand, but we included references

to them because they are the place to go if youreally need to get to the bottom of a story (and tofind the cutting edge) What’s more, for manyscientists, evidence doesn’t really exist until it hasbeen published in a scientific journal For this tohappen, the study has to be reviewed by otherscientists working in the field, in a system calledpeer review Although this system has biases, andmistakes are made, it is this that makes science acollective endeavor and provides a certain

guarantee of quality

The way journal articles are cited is quite precise,

and in this book we’ve followed the AmericanPsychological Association reference style (

http://www.apastyle.org ) Each looks something

Before the year of publication (which is in

parentheses), the authors are listed After the year

is the title of the paper, followed by the journal inwhich you’ll find it, in italics The volume (initalics) and then the issue number (in parentheses)follow Page numbers come last One conventionyou’ll often see in the text is “et al.” after the mainauthor of a paper This is shorthand for “andothers.”

Many, but not all, journals have an electronicedition, and some you can access for free Mostare subscription-based, although some publisherswill let you pay per paper If you go to a library,generally a university library, make sure it not only

subscribes to the journal you want, but also has theyear in which the paper you’re after was

published

If you’re lucky, the paper will also be reprintedonline This is often the case with classic papersand with recent papers, which the authors mayhave put on their publications page A good query

to use at Google ( http://www.google.com ) for

papers online in PDF format using a query like:

"What the Frog's Eye Tells the Frog's Brain" filetype:pdf

Alternately, search for a researcher’s name

followed by the word “publications” for papers,demonstrations, and as-yet-unpublished research, agold mine if you’re learning more about a

particular topic

Recommended Reading

If you’re interested in getting a general overview,rather than chasing the details of a particular story,you might like to start by reading a book on thesubject Here are some of our favorite books on

our own pet topics, all of which make specialistmaterial accessible for the rest of us:

Descartes’ Baby: How the Science of Child Development Explains What Makes Us Human

by Paul Bloom (2004) Lively speculation from

a leading researcher

Natural-Born Cyborgs: Minds, Technologies, and the Future of Human Intelligence by Andy

Clark (2003) Clark asks whether intelligence

is bounded by our skulls or is part of the toolsand technologies we use

Symbolic Species: The Co-Evolution of

Language and the Brain by Terrence Deacon

(1997) A dizzying, provocative integration ofinformation across different disciplines

Consciousness Explained by Daniel Dennett

(1991) Psychologically informed philosophy.Consciousness isn’t explained by the end, butit’s a fun ride along the way

Eye and Brain: The Psychology of Seeing by

Richard Gregory (1966) Erudite and

good-humored—a classic introduction to vision.

The Nurture Assumption: Why Children Turn Out the Way They Do by Judith Rich Harris

(1998) The Evolutionary Psychology of childdevelopment, a great read that challenges theassumption that parents are the most importantinfluence in a child’s life See also the web siteat: http://home.att.net/~xchar/tna

Mind Wide Open: Your Brain and the

Neuroscience of Everyday Life by Steven

Johnson (2004) How the latest developments

in brain science and technology inform ourindividual self-understanding

The Language Instinct: How the Mind Creates Language by Steven Pinker (1995) Compelling

argument for our innate language ability andbrain structure being reflected in each other

Phantoms in the Brain: Probing the Mysteries

of the Human Mind by V S Ramachandran &

Sandra Blakeslee (1998) Tales of what braininjury can tell us about the way the brain works

The Man Who Mistook His Wife for a Hat and Other Clinical Tales by Oliver Sacks (1995).

Informative and humane anecdotes about

patients with different kinds of brain damage

If you’re looking for something a little deeper, werecommend you try:

The Oxford Companion to the Mind, edited by

Richard Gregory (1999) Authoritative andentertaining collection of essays on all aspects

of the brain

Godel, Escher, Bach: an Eternal Golden Braid

by Douglas Hofstadter (1979) The classicexploration of minds, machines, and the

mathematics of self-reference The back of mycopy rightly says “a workout in the finest mentalgymnasium in town.”

How to Think Straight About Psychology by

Keith Stanovich (1997) How to apply criticalthinking to psychological topics

How This Book Is

on the outside to taking pictures of the inside)—that’s half of this chapter The other half speaks

to the second question: we’ll take in some ofthe sights, check out the landmarks, and explorethe geography of the brain

Chapter 2

The visual system runs all the way from the way

we move our eyes to how we reconstruct andsee movement from raw images Sight’s animportant sense to us; it’s high bandwidth and

works over long distances (unlike, say, touch),and that’s reflected in the size of this chapter.

Chapter 3

One of the mechanisms we use to filter

information before it reaches conscious

awareness is attention Attention is sometimesvoluntary (you can pay attention) and sometimesautomatic (things can be attention-grabbing)—here we’re looking at what it does and some ofits limitations

Chapter 4

Sounds usually correspond to events; a noiseusually means something’s just happened We’llhave a look at what our ears are good for, thenmove on to language and some of the ways wefind meaning in words and sentences

Chapter 5

It’s rare we operate using just a single sense;

we make full use of as much information as wecan find, integrating sight, touch, our propensityfor language, and other inputs When senses