"In this episode of the human senses we.re going to explore our 2 most highly developed senses, touch and vision." "How does our visual system measure up to the best eyes in the animal kingdom?" "We.ll be testing the amazing things we do with our eyes." "How we can instantly spot attractive people in a crowded room," "our eyes guide us around the world with astonishing accuracy," "and even let us see in to the future." "When it comes to touch we.ll reveal why we love the feel of some things." "And loathe others" "We.ll discover what our skin has in common with an elephants." "And we.ll explore the fascinating world of pain." "And how we have an amazing ability to block it out." "I can.t feel anything at all." "And as the ultimate test of mind over body we.ll see what happens when a brave volunteer tries taking part in a circus act, you.d think would be excruciating." "Jim Rose and his team of circus performers are experts in self-mutilation." "They specialise in stunts that look very painful." "We.re going to find out how it.s possible to do all this without apparently feeling intense pain." "We basically over come what we would call discomfort, and I think you might, er a lot of people might call er pain." "We.re going to find out how we can all learn to combat pain by controlling our sense of touch to an astonishing degree." "We use touch to explore the world." "Instantly we can tell how something feels to us." "its kind of wet... flaky and, slimy, sandy." "Frozen and grungy." "But our sense of touch does much more than just tell us what.s there." "urgh." "oh it.s horrible." "When we feel something straight away we know whether we like or loathe it." "That is a foul huh." "urgh." "There are things most of us find repulsive." "that is really gruesome. oh god. urgh oh my god they.re maggots." "strange to believe but it I think I like that one." "But touching something smooth and soft feels lovely." "ooh that.s very nice." "I could sleep in a in a large mattress of this stuff." "Yeah nice and fluffy." "so why do we care so much about how things feel?" "We.ve come to Jodhpur in Northern India, to pay a visit to some distant relations," "a trop of hanaman Langers." "These monkeys hold clues to the origins of our sense of touch." "For most animals the occasional touch is part of normal life." "But monkeys adore touching and being touched." "We come from a long line of touchy feely ancestors and for them like us touch is more than just simply exploring the world." "lt.s not about keeping clean." "Touch is how they get along." "scientists have shown that grooming releases endorphins in to the blood stream." "Endorphins are feel good chemicals." "so it.s a stress reliever for the monkey that.s being groomed." "And even for the monkey that.s doing the grooming." "Grooming just about anything makes them feel good." "And from our monkey ancestors we.ve inherited the same strong feelings about touch." "And ingenious way of telling good from bad." "Embedded in the surface of the skin there are millions of touch receptors." "And it.s those that relay the sensation of touch right to the brains." "sensing what.s touching us is actually a remarkable piece of detective work." "Because there are no specific sensors telling us whether something.s wet or dry, or rough or smooth." "so how can we tell if it.s a drop of oil or the stroke of a hand?" "Touch receptors only monitor basic things like pressure temperature and minute vibrations on the skin." "They feed this information as nerve signals to the brain." "lt.s the exact combination of signals coming from them skin that allows the brain to work out what.s touching us." "But our sense of touch does more than just tell us what.s there." "our skin is also designed to protect us from damaging ourselves." "When a firm touch gets too much it suddenly feels very different." "It hurts." "This is hurting because special pain receptors are firing." "our pain receptors, they do nothing except scream at us when things get just too rough, argh." "There.s actually a lot more to pain than you, might think." "This is just the beginning, argh." "If we.re such touchy creatures how do people like Jim Rose do things which look so painful" "Well curiously back in India, there.s a another animal that provides a useful tip" "Much of an elephant.s hide isn.t very sensitive at all, just as well." "If you spend you life being scratched and scraped by thorns." "A forest of spiny lantana catches on your skin, and your clothes." "To go through stuff like this you need a hide as thick as old boots." "And that.s why, elephants, aren.t offended if you call them thick-skinned." "In fact zoologists refer to elephants as pachyderms." "Which literally means thick skinned." "so while this lantana thorn scrub would tear your legs to shreds these elephants hardly seem to notice it." "Their skin is so thick it takes a lot to scratch an itch." "That sound it.s enough to make you wince." "But not all of an elephant.s skin is so tough" "The finger like tip of the trunk is extremely sensitive." "And has the highest density of touch receptors anywhere on the elephant.s body." "Where they.re most sensitive to touch they.re also most sensitive to pain." "so elephants approach things very gingerly with their trunks." "Thank you." "The sensitivity of the elephant.s skin to touch and pain varies enormously over its body." "From the delicate soft snout to its thick leathery hide." "We probably seem as strange to an elephant as they do to us." "We look so different but when it comes to our sense of touch we.ve actually got a lot in common." "Their touch receptors are concentrated where they interact most with the world." "And so need to have the best sense of touch." "And in that respect we humans are exactly the same." "And generally we feel less pain in areas, which are less sensitive to touch." "A tiny paper cut on your finger is excruciating." "But you can cut your leg and it doesn.t hurt nearly as much." "so we feel things very differently across our bodies." "But that.s not just because of the number of touch receptors in the skin." "Each area of the body sends touch signals to a particular area of the brain." "If the size of your body parts reflected how sensitive they are, you.d be in for a shock." "our extremely sensitive hands would be huge." "Your feet would be as big as your chest, and half of their length would be your toes." "lt.s no wonder they.re so ticklish." "And your face is much more sensitive than your chest and back so that too would be bigger." "Your lips would put Mick Jaggers to shame." "Your tongue would be as big as your already oversized hands." "Put it all together and you.d have something that even a mother would find hard to love." "so because we feel things so differently in different areas of our bodies." "Things are always going to hurt a lot less on your back and your legs." "But when it comes to confronting pain there.s another vital aspect of our sense of touch that can help." "sometimes we completely ignore the touch signals coming from our bodies." "It happens all the time." "You don.t notice your clothes touching your skin." "Its amazing how little we sometimes feel." "Mark Mittern is a magician who claims he can remove someone.s watch while doing a card trick." "You want to see a quick trick?" "Are you at all interested in in er seeing some magic?" "The most physic among you." "Who.s the person that can read minds?" "Pull a card trick is that cool?" "I want you to name a card that.s going to appear right here, ok?" "Any card you want." "Whatever you want." "Ace of spades." "4 of hearts 6 hearts" "1 0 of diamonds." "Alright." "And grab it by the wrist." "I want you to name a card that.s going to appear right here, ok?" "Yeah hold them really tight so there.s no way I can get at the cards." "lt.s going to appear on my hand on the count of 3." "7 of spades." "look at his right hand." "Really bare down so I can.t" "And yes there goes the watch." "Amazingly no one misses the feel of the watchstrap on their skin." "And inside of my hand look." "Look 5 of diamonds." "5 of diamonds." "Look inside of my hand like this." "Do you see it?" "Inside my hand you can see it right there." "oh shoot but something very strange happened." "Did you see it?" "No what.d you do?" "look in your hair, oh my god my watch." "1 0 of spades." "When something more important seems to be happening else where, your brain chooses to ignore some touches." "I forgot, we have a gift for you, ok." "lt.s a special gift." "oh my watch" "You have my watch." "you your nuts." "Your still crazy oh thank god." "How about this?" "That.s my watch" "you.re good." "so if we can tune out gentle touches what about more intense sensations?" "can our brains alter how much pain we feel?" "Professor Tony Dickenson has devised an experiment using electric shocks." "If we.re expecting something to hurt will it feel more painful?" "These students think they.re going to be testing 2 new drugs." "A yellow pain killer or a brown pill, which will actually make them more sensitive to pain." "What we.re now going to do to you is erm a pill." "And in this case this pill is going to actually potentially increase your pain." "Right." "of course the the pill we gave you might well be a painkiller, an analgesic so that you could feel a lot less pain." "so the students think they.ve taken either a painkiller or a pain booster that will make them more sensitive to pain." "When in fact the pills do absolutely nothing at all." "They.re both just sugar and flour mixed with food colouring." "so what we.re going to do now is l.m going to apply some small electrical shocks to your wrists, through these 2 pad electrodes." "l.ll be increasing the stimulus." "lt.s not going to damage you and at any point if its unpleasant discomforting let me know and we.ll stop." "so ok shall we start?" "the volunteers that think they.ve had a painkiller are expecting to feel less pain, and show little or no reactions to the shocks." "But even though the shocks are exactly the same, those that think they.ve taken a pain booster expect to feel more pain." "And sure enough they find the shocks much more unpleasant." "And as the level of shocks reaches the maximum those that believe they.ve had a painkiller still show little reaction." "But at the same level for the other group the suffering becomes just too much." "They.re actually feeling more pain." "so we show that expectation had a marked effect on the amount of pain that these two groups felt." "so in the group who.d been told they.d had a painkiller, they could put up with much greater electrical shocks." "The other group where we told them that the pill they.d taken was going to increase the amount of pain that they would feel, in that group they called a halt very early on in the series of shocks." "lt.s all down to the power of expectation." "If you think something.s going to hurt, then the chances are, it will." "stop, stop, stop." "I can cope going higher its just not nice." "ok." "Without even knowing we.re doing it we can control the amount of pain we feel to a tremendous degree." "We.re going to find out how its possible to take an experience, something as extreme as this?" "And make it feel as pleasant as this." "There.s a way to do just that." "And one man who knows how is at stamford university in california." "Professor David spiegel." "He.s studying how hypnosis can sometimes help reduce chronic pain that can.t be treated with drugs." "Hypnosis is a naturally occurring state of highly focused attention coupled with physical relaxation." "People go in to it all the time, every day." "When you.re in a movie and you get so caught up in the movie that you start to think it.s the real world." "That.s a hypnotic like state." "To demonstrate the power of hypnosis to control pain," "Prof. spiegel is going to hypnotise our volunteer and then stick pins in to his left hand." "And then close your eyes slowly, let your body float." "The volunteer is told to imagine his left hand is in numbingly cold water." "I want you to imagine that your left hand is dipped in to a bucket of ice water." "His right hand should be a sensitive as normal." "Feel a bit of breeze on it... l.m feeling that yeah." "ok so now we.re going to see how your hand feels when we test the sense of pleasant cool tingling numbness." "How.s you hand feeling now?" "research from brain scans has shown how hypnosis effects the brain." "The pain from the needle triggers two areas in the brain." "The first tells us that our hand is hurting." "The second controls just painful it feels." "Hypnosis turns down the brain activity in both these areas so reducing the amount of pain the subject feels." "so what does it feel like in you left hand and arm?" "Any discomfort?" "Amazingly in his left hand which he.s been told to imagine is numb this volunteer doesn.t mind the needles sticking in to his hand." "But in the right hand, which he.s not imagining is numb;" "the needles are unbearable causing shooting pains up the arm." "sorry how is it now?" "yeah that.s better." "Alright so now we.re going to remove the needles, that of your left hand." "out they come." "Do you feel anything now?" "No I feel nothing at all." "Deep breath and we.ll come out of this state of self-hypnosis, feeling relaxed and refreshed." "You really didn.t feel it in here huh?" "No not at all." "That.s great that.s great you did very well it was there for quite a while yeah." "All hypnosis is really self-hypnosis, it.s just a way of teaching you how to use your capacity that you have naturally, but focus it on a certain strategy to deal with pain." "so basically you can go into the self hypnotic state by anything that gets you to turn inward to pay attention, turn inward cut out your awareness of outside cues and that you can learn to do all by your self." "so is our guinea pig now ready to lie on a bed of blades." "Jim wife had a plate broken with a cannon ball." "But now he.s thoughtfully lined up something else." "We.ve discovered several ways to help cope with the pain." "Just like the elephant some areas of our skin are much less sensitive." "so lying on your back should make it less painful." "Expectation has a lot to do with the amount of pain we feel." "Despite our keen sense of touch we can actually reduce the amount of pain we feel." "If you can relax and focus on something else, than the theory goes lying on a bed of blades should be a breeze" "My friend you.re going to have to take of that er T-shirt." "You.re going to do this bare backed." "That.s right." "That.s right I told you he had hair in places monkeys don.t" "obviously there.s a degree of showmanship with Jim.s act." "so this can.t be as nasty as it looks." "But even so it.s not something to try at home." "one other thing, you can never be too safe." "There you go." "ignore the... 1 swim swim." "2" "swim dont be there." "Take a look at that back." "Take a look at that back" "come on." "so with our minds we have astonishing power to control how painful things feel to us." "our brain decides what touch sensations we register and what we ignore." "And in that respect our sense of vision is surprisingly similar." "In the second half of the programme we.re going to reveal the fabulous things our visual systems can do." "But we.ll also discover why our brains can fail to register the blindingly obvious." "Would you spot this change over?" "Get your video recording now and at the end of the programme you.ll discover how much you missed of what was happening right in front of your eyes." "The south African Bush." "We.re here in search of a deadly animal whose vision is just like ours in one extraordinary way." "she.s a cobra, and has to be approached very carefully." "Her flared hood is a warning." "If provoked she could unleash a venomous strike, which could kill me in minutes." "But there.s a little known fact about snake.s eyes." "If you stay still enough she shouldn.t be able to see me." "Because the light sensing cells in her eyes tire if what.s they.re looking at doesn.t change." "Faced with a static person the snake relaxes." "But any sudden movement and the cobra attacks." "Like all animals this snake has evolved to see just what she needs to see to survive and not much more." "we.re just the same." "The human visual system is superbly good at some things, but we can also miss an amazing amount of what.s happening right in front of our eyes." "We.re in the skies above Los Angeles, one of the few places where they.ll let you play tag with real planes." "We.re about to put the co pilots eyes through a high-speed work out." "Forget video games this is the way to test just how much our visual can cope with." "The co pilots job is to stop the other plane closing in at over 300 miles an hour." "Then he has to get him in his sights and keep track of him as his plane hurtles around the sky." "All he.s looking for is a tiny spec in this empty sky." "This takes real concentration." "There he is, the planes caught the co pilots attention because it was moving." "so his eyes were automatically drawn to it." "He knows he.s been spotted so now he tries to loose the chasing plane." "Even at speed the co pilot can follow him as the chase plane banks and spins his visual system has no trouble keeping track of which way the target plane is moving, and how far away it is." "If the chasing team can get their laser on the other plane will have to surrender and let off a smoke trail." "This 3 dimensional high-speed pursuit shows what we can do with our eyes." "But how does our visual system measure up to the rest of the animal kingdom?" "There are plenty of exotic creatures equipped to see in truly fabulous ways." "The mantis shrimp has remarkable eyes on stalks, which scan the world in 1 2 different colours." "chameleons have eyes, which can swivel independently." "so one eye can be on the look out for danger, while the other lets them grab their supper." "And some animals have much sharper eyes than us." "From over 4 miles away an eagle can spot prey that would be completely invisible too us." "These animals all have eyes suited to their needs." "so what have ours evolved to be good at?" "We are group living animals and our real speciality is looking at the people around us, especially if we fancy them." "In a busy nightspot we.ve decided to test exactly what people.s eyes get up too." "With the help of psychologist Ben Tatler and cathy Hughes." "some volunteers have agreed to put on a headset that will record every move made by their eyes." "our eye track it gives us the opportunity to see where we.re actually looking." "Erm and this this kind of important to record." "Because the eyes are moving about all the time." "They.re they.re darting around 3 times a second." "And we.re certainly not aware of this." "so we need some kind of piece of equipment that.s going to show us what.s happening." "our volunteers think they.re going to the back of the bar to be tested by the psychologists." "But the real test is actually before that." "They.re asked to wait next to 2 women and a man who.ve been planted there." "All attractive models." "How much will our volunteers ogle them?" "And if they do will they know they.re doing it?" "Time to play back the tape and our first victim is in for a surprise." "checked this guy as you went by." "Did you realise that you were looking at him?" "No I noticed someone over there, they were laughing at me." "That.s all I did." "Not not that particular person" "she was very interested in our male model in the sleeveless T- shirt." "And it.s not just his face she.s checking out." "Next she takes a look at the blokes bottoms along the bar." "And she had no idea she was doing it." "lt.s an eyes opener for me l.m amazed, absolutely, absolutely." "In fact all our volunteers claim they weren.t aware of where they were looking." "Did you realise how much you were looking at them?" "cause you were looking at these 2 girls quite a lot." "No." "In our test the women actually ogled more than the men." "our last volunteer just thought she was talking to her friend." "But her eyes were all over the guy in the camel coat." "l.m really embarrassed." "I don.t even know theres a guy in the bar with a camel coat on." "And yet I must.ve been sat looking at him. oh my god, oh no." "our brains are so good at people watching that we do it automatically without even realising." "so I guess the great thing at looking at eye movements and looking at where we look." "is that it does give us a window in to the way that the brain is working." "What the brain is interested, at some kind of subconscious level." "Even though it never gets through the point of us being aware." "our eyes never settle, and there.s a good reason why they.re constantly darting around." "lt.s all to do with the basic design of the eyeball." "ophthalmologist Dr Bill Aylward takes a snap shot of the back of the eye." "What you can see here are blood vessels, running over the surface of the retina." "And beneath them are light sensitive cells, which allow you to see." "Lining the inside of each eyeball there are over a 1 00 million light sensing cells." "But only the bigger cone cells see in colour." "And amazingly only in one tiny area of each eye are there enough of these cone cells jammed packed tightly together for sharp colour vision." "Most of the retina er er gives you vision which is quite blurry, apart from this very small area in the middle." "Just that smudge that we can see there." "This little smudge here that really gives you really fine detailed vision." "And that bright spot is even odder." "An area which is completely blind." "That.s where all the blood vessels come in and out, and where all the optic nerve fibres go back to the brain." "Er and theres so much going on there that there aren.t actually any light sensitive cells in that area." "And that corresponds to your blind spot." "so it is a very odd design." "so if our eyes are designed with a blind spot and a mostly blurred image, how do we see the world in such intricate detail, and such vivid colour?" "The patchy image made at the back of the eye is just the beginning of how we see." "As our eyes dart around we make sure that anything interesting is lined up on our sharp spot, so we get a good look at it." "And you don.t know you.re doing it." "Because the brain takes these jerky snapshots and creates a nice smooth movie of the world." "And the brain also compensates for the blind spot." "Because our eyes give us slightly different images we can combine them to give one complete picture." "our visual system is constantly keeping track of what.s out there and where it.s moving." "But it goes way beyond that." "some times we can even see things before they.ve happened." "scientists have recently discovered that baseball hitters do something quite extraordinary." "The ball is moving so fast that the hitter can.t simply watch the ball as it comes towards him, and then adjust his swing." "so how does his bat end up in the right position?" "Your average novice tries to follow the ball through the air and then take aim that.s disastrous." "lt.s impossible l don.t even know how you catch it?" "Top baseball stars like Gabe Kapler don.t even try to watch the ball." "You know they say that erm its almost impossible for us to track the ball actually from the pitchers hand all the way in to the catchers glove." "or when we make contact with the ball." "But er you know I don.t know if that.s true or not all I know is that natural ability tends to take over and the repetitive action that you do on a day to day basis as a hitter er tends to take over." "After facing thousands of throws" "Gabe has learnt to see in to the future." "scientists have discovered that within a few thousands of a second of the ball leaving the pitchers hand," "Gabe.s brain analyses the speed, spin and angle of the ball." "And then he predicts where it.s likely to end up." "so he.s swinging at the ball before any normal human being would know where it was going." "And he does it with astonishing accuracy." "Most of us aren.t quite that skilled." "But every time we cross the road, we all use our eyes to predict where things will move." "With each glance our brains are worring away." "Working out where cars will be so we can dodge the traffic." "We rely on our eyes to guide ourselves around the world." "lt.s all about co-ordinating our sense of vision with our bodies." "But we.ve not even born with the basics." "Babies have to learn where things are and what they have to do to grab them." "And until they get it right it can be a frustrating process." "As adults we take it all for granted." "But ln chicago Physiologist Hubert Dolizal has devised a bizarre way to test how well our brains can adjust." "When everything we.ve spent years learning is turned on his head." "He.s built a set of goggles that flip the world up side down." "Hello Hubert." "Hubert has been wearing his goggles non-stop for 2 weeks now." "We.re going to see how well our human guinea pig learns to cope after just a few hours." "oh wo ho that is so weird." "At first it.s totally disorientating, but at the end of the day we.re going to see whether it.s possible to ride a bike with the goggles on?" "Where are you its?" "l.m right here." "Now here we go," "Look at you lets shake hands." "Argh ha" "First its back to Hubert.s flat." "And to start with a simple task that any child could do." "Its so weird and my hand it just you know disembodied." "lt.s back to square one." "Tell you what l.m going to have a new admiration for babies now." "When you see them playing and trying to stack things." "Good for you" "There is a great gaping fridge there." "And I can.t work out how to get my hand in." "Everything that normally happens automatically is now a real struggle." "You have to think about what you.re seeing, work out where things are, and then move your hands." "It makes you realise how even the simplest movements depend on accurate guidance from our eyes." "Where is my hand?" "At first anyone entering this strange upside world has the hand eye co-ordination of a toddler but after a few hours there are signs of improvement." "Hubert seems to have no trouble, but then he.s spent weeks wearing the glasses, and to begin with he was just as bad." "Whoops, whoops I just realised that l.m going to drink it with my forehead." "ohh l.m sorry." "As the days went by Hubert adapted brilliantly." "His brain started to make sense of this topsy-turvy world." "Making the right movements automatically without having to think about it." "ooh." "After 8 hours Its time for our volunteer to attempt riding the bike." "Yoo hoo!" "It takes a monumental effort of concentration not to fall off, but he.s just about hanging on." "The human sense of vision is superbly good at some things." "spotting attractive people in a crowd, guiding us around the world." "And even predicting where things will end up." "Doing all that takes a lot of brainpower." "Almost a third of the brain is taken up with vision." "But there.s a limit to how much we can see without overloading the system." "so something has to give, which is why we sometimes miss things happening right in front of us." "A shopping centre in London." "This man is going to go up to people and ask for directions." "Then a door comes through and he swaps with some one else." "sorry what were you saying." "They don.t look that similar, so do you think people would notice the swap?" "There are 4 cameras hidden around the shopping centre so we can secretly film how people react when some one they.re talking to suddenly changes." "After a bit of practice its time to start the experiment." "Excuse me do you live around here?" "sorry where?" "so did the unsuspecting members of the public notice that they.d been speaking to 2 different people?" "No I didn.t and I think I walked away thinking damn l can.t help that guy." "And he.s gone off in the wrong direction." "I really don.t know where he.s going..." "Where where?" "less than half the people noticed the swap, which is exactly what happens whenever, this experiment is done." "Even though the first person who stopped them swapped with someone different did they think they were still talking to the first person?" "Yeah I did" "Excuse me sorry to trouble you, do you live around yep, you haven.t heard of west, west street?" "What and what about?" "They.re looking right at the experimenters faces." "But their brains are too busy to register what their eyes are telling them." "Most of the time our vision does a wonderful job." "But there.s a limit to how much our brains can cope with." "so we just pay attention to one thing at a time." "And we.re blind to the rest." "The brain has a huge amount of information er being delivered to it by the eyes." "It has to make the decision; it has to decide where to place its attention." "What information it should scrutinise, what information it should ignore." "To test just how much we ignore" "Richard Wiseman and the London Towers basketball team have agreed to try out an experiment designed by scientists at Harvard university in America." "The idea is simple but silly." "The team are filmed practising and then this happens." "surely no one would miss that?" "A group of people are invited along to a bar to take part in an experiment." "And Richard gets them to watch the screen without letting on what they.re being tested for." "so this is an experiment, it.s a battle of the sex.s men against women, they.ll be a difference." "But l.m not going to say which way round its going to be." "And it.s just a simple observation test." "All you need to do, as you.ll see there are 3 guys I yellow here and they have a basketball." "And it.s your job to count the number of times they throw the basketball to each other." "Now to make things slightly harder er there.s also 3 guys in blue tracksuits." "You ignore them, ignore their basketball and just concentrate on this one." "so er if we can run the tape." "ok so that.s number 1 ." "crucially the volunteers are told to count how many times the yellow team passes the ball." "But will that be enough to make them miss the gorilla?" "so did they see anything?" "ok if we can stop the tape there for a moment." "so many er how many basket ball throws." "20?" "Any more of the others 21 ok." "ok at to be honest here any body notice anything a little bit unusual, be honest." "ok so just about 4 or 5 of you excellent." "The rest of you not notice anything strange honest?" "ok, right for you guys enjoy this moment." "Er when the first time I saw this it completely threw me." "Now I want you to watch the tape again but this time just watch it as you would a normal piece of television." "No counting the basketball anything like that." "If we can have the er the tape." "Time to show them what they missed." "here it comes." "No way!" "chatter." "because they were all concentrating on counting, their brains just didn.t register the gorilla." "l.m l.m absolutely shocked." "I can.t believe that." "I was so proud of myself as well because I got all 20 and I was so busy concentrating on it that I didn.t know." "l.m embarrassed I thought l.d spot the monkey walking across the middle of the screen." "I was completely astounded." "It was just kind of when he did the kind of like that I was just absolutely amazed." "It was I was gob smacked l.d say." "I can.t believe and saying they might have probably switched the video or something like that." "I can.t believe that you could miss something that obvious." "That.s really bizarre it.s freaked me out a bit." "We rely so much on our eyes it seems extraordinary that we can overlook what.s right in front of us." "But theirs a limit to what our visual system can take in." "its just that normally we.re not aware of quite how much we.re missing." "And if you don.t think you.ve missed anything as blatantly as obvious as this." "some one in a gorilla costume how many times have you seen my friend popping up during the programme?" "Don.t feel bad if you.ve missed him." "But its only because your brain has been busy doing other things." "Go on if you don.t believe me rewind the tape." "our sight is phenomenal." "It can guide us through a fast moving world." "spot a pretty face and even see things before they.ve happened." "But sometimes just sometimes you shouldn.t trust your eyes."