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sound site smell feel taste in other

senses do more than tell us what's going

on in the world around us they can make

us feel things like emotional things not

just texture and heat and in our minds

these senses aren't always so distinct

one sense can blend into another in the

end everything we know is just our

interpretation of reality how do we even

know that i'm speaking right now our

minds are totally capable of making that

kind of thing up here's how that works

so there's a thing happening on the

internet that you might have seen viral

gifs or gifs no one's decided for sure

yet that seem to have a sound they're

silent like all gifs but if you're one

of the many people that experience a

phenomenon known as veer you might have

heard them veer stands for visually

evoked auditory response it's only

recently been identified in a paper

published in 2017. though initially veer

flew under the radar it got launched

into the spotlight in december of 2017

when a gif of a bouncing electrical

tower went viral on twitter we'll stick

it in the description for you to see

according to the highly unscientific

twitter poll alongside said tweet a

majority of respondents perceived sound

from the jiff as the tower hit the floor

that's a pretty sizable number of course

there's always the possibility that a

lot of people were just going along to

feel included but then again there's

whole subreddits devoted to noisy gifs

even so that tweet caught the eye of a

whole lot of psychology researchers who

promptly got really excited scientists

from around the world started weighing

in on possible solutions one particular

scientist from city university london

spotted the tweet and immediately

thought it was a great real world

example of work on veer published by his

lab only a few months prior in that 2017

paper published in the journal

consciousness and cognition the

researchers looked at sensations of

sound that could be evoked by flashes of

light when asked if the presentation of

flashes were accompanied by a sound 22

of their participants said yes and then

in order to confirm those reports of

perceiving sound investigators also

tested participants on a more objective

measure they called visual morse codes

in this study a white disk presented on

a black background turned on and off in

particular morse-like patterns the

participants that reported hearing the

flashes were significantly better at

identifying whether pairs of morse code

flashes were the same than those who

were unable to hear flashes those that

heard the stimuli seem to be turning the

visuals into auditory information which

stores timing way better than visual

information does kind of like an audio

cheat sheet that other participants just

didn't have access to harnessing the

power of the twitter storm these

researchers started talking to news

outlets about their theory and at the

end of articles interviewing them many

outlets provided a link to the

researcher's new study investigating the

phenomenon all in all they got over 4

000 responses from around the world

about just how people experienced the

supposed sounds these gifs were making

the data showed that videos depicting

situations with a lot of movement energy

or predicted loud sounds like a car

crash were most likely to trigger veer

and though they didn't have tests good

enough to measure it directly the

researchers suggested that veer may be a

kind of synesthesia synesthesia is a

crossing over of senses when one sensory

modality like hearing is stimulated

those with synesthesia might perceive

something in a different unstimulated

sensory modality they might associate

certain types of music automatically and

reliably with certain colors or patterns

for example there are a lot of different

types of synesthesia everything from

sensing particular personalities from

numbers to perceiving different kinds of

erotic stimulation with specific colors

we don't have a single unifying theory

of what happens in the brain to cause

synesthesia yet but many scientists

believe it's the product of an increased

communication between sensory areas that

don't usually talk that kind of sensory

overlap certainly seems similar to veer

but whether or not veer is a kind of

synesthesia is still very much an open

question if it is it could be pretty big

for synesthesia research the prevalence

of veer seems to be much higher than

that of other types of synesthesia and

the scientists involved believe that the

prevalence of sensory crossover seen in

veer might challenge the idea that

synesthesia is anything other than a

part of normal variations between people

maybe it's more normal to have senses

cross over like this than we first

thought however this isn't the only

theory that could explain noisy gifs

some people have also highlighted the

possibility that it's not actually a

synesthesia-like process it could be

that visual brain areas are providing a

sort of pre-emptive nudge to the ear to

brace for expected sound the acoustic

reflex is a contraction of the stapedius

muscle a tiny muscle in the middle ear

that occurs in response to loud audio

stimuli that decreases the vibrational

energy transmitted to the cochlea the

part of the inner ear that translates

vibrations into neural firing the

acoustic reflex is well documented in

scientific literature and can be used to

gain insight into a lot of different

hearing conditions it also may produce

an unexpected noise in the ear when it

happens since it pulls the inner ear

into a slightly different shape so it

might be that the acoustic reflex isn't

just responding to the sound happening

but being prompted by the visuals

predictive of a loud noise that would

explain why research has found that

videos showing situations predictive of

loud noises trigger veer the brain might

be preempting a sizeable sound and is

letting the ear know like hey it's about

to get real loud nearby while we haven't

nailed down the exact mechanisms behind

veer or why some people have it while

others don't research is still ongoing

to find out what is clear though is that

we've only scratched the surface when it

comes to decoding the complex ways our

senses interact that and sometimes

tweeting about weird stuff results in

actually advancing science gif jif fungi

fungi we haven't collectively decided

how a lot of these things sound we read

it and come up with an idea of how we

think it should sound but different

people have different and very firm

beliefs about that sound but how strong

would you feel about a sound you can't

hear or a sight you can't see sometimes

individuals without sight as we know it

can still process visual information

here's brit to explain how that works

most of the time physical blindness is

like a blindfold it keeps people from

taking in visual signals at all but

there's a surprising exception to that

rule in some rare cases people can lose

their vision but still respond to visual

cues except they do it subconsciously in

other words they can see without knowing

they're seeing this condition is called

blindsight and not only does it shed

light on how vision works it also offers

some clues to human consciousness the

first person to observe blindsight was a

grad student in the late 1960s who was

working with a rhesus monkey named helen

helen's primary visual area known as v1

had been surgically removed so

scientists could study that region's

role in vision generally speaking

whether you're a human or a monkey

damage to v1 makes you blind and as far

as anyone could tell helen could

basically only tell apart light from

dark but the grad student noticed that

if he held up a piece of fruit helen

would look at it and reach to grab it

she could also navigate through

obstacles to eat crumbs off the floor so

at times she seemed to act like any

monkey with typical eyesight but other

times like when she got upset she'd

still stumble around like she couldn't

see so in some ways she was clearly

blind of course helen couldn't tell

anyone what her experience was like so

no one knew for sure what was going on

until a similar thing showed up in human

patients in one famous case a patient

known as db had brain surgery that

accidentally damaged one side of his

vision center so he could no longer see

anything to the left of his nose but a

researcher noticed db would reach for

things outside his field of vision as if

he could actually see certain things in

his blind spot so a team of researchers

came up with an unusual experiment they

would shine a circle of light into his

blind spot then ask db to point at it

and he'd say he couldn't because he was

blind but if they asked him to just

guess he was usually right the

researchers also projected lines on a

screen and asked db to guess whether

they were horizontal or vertical and

even though he assured them he couldn't

see anything he guessed right more than

80 of the time which is way better than

random chance and db wasn't the only

person with this apparent superpower

another patient named tn had his visual

centers damaged from two separate

strokes that left him completely blind

but again scientists suspected there was

more to the story on one occasion they

asked him to walk down a supposedly

empty hallway except

it wasn't empty the scientists had

filled it with boxes chairs a file tray

and all sorts of obstacles but tn

perfectly dodged every single one except

afterward he had no idea that the

hallway was anything but empty so how on

earth can people do this scientists have

some ideas first of all in each of these

patients the same part of the brain was

damaged that v1 region that had been

removed from helen the monkey scientists

think this region is where signals from

your eye turn into conscious sight but

v1 is just one part of a complex network

that gives us our vision see when

signals leave your retina and travel

through the optic nerve they don't go

straight to v1 their first stop is a

part of the brain called the thalamus

which is sort of like a relay center

from there most visual signals go on to

v1 but two other paths lead signals to

different parts of the brain the

amygdala and a region called hmt plus

the amygdala is involved in emotional

responses like when you're scared and it

acts subconsciously so for example you

can react to something scary even before

you've consciously understood what

you're reacting to like if you open your

apartment door and find a crowd of

people inside you might jump before

realizing it's a surprise party in other

words even if the signals going to v1

hit a dead end because it's damaged the

amygdala is still getting visual signals

and responding to them even when you're

not consciously involved hmt plus is

another part of the vision system that

tracks movement by picking up on things

like change and contrast it also gets

signals from the thalamus and scientists

think people may be able to register

where things are moving in their visual

field even though it can't see the thing

that's moving those are two possible

ways people might be able to see when

they're blind but it is possible there

are simpler explanations for example

humans rarely have v1 completely damaged

and like db they usually have vision and

at least part of their visual field and

in some cases maybe patients are able to

make accurate guesses because of light

scattering to the parts that can see

there are also some people with blind

sight who report seeing

something like waves or shadows and

these things might influence how they

answer but many patients are just as

surprised by their abilities as the

experimenters the idea of subconscious

signals influencing people's behavior

isn't new though we've known about

unconscious perception for decades

scientists have recorded many examples

of people reacting to images or words

that flash in front of them too quickly

to register consciously but one of the

interesting things about blindsight is

it shows that our conscious experiences

are just a small part of the work our

brains actually do no one knows what

makes us conscious or why we experience

life instead of just going through the

motions like a robot but research on

blindsight gives us an unusual window

into this problem it shows us that

certain brain regions seem to be

responsible for our conscious experience

of vision and it also tells us that in a

lot of ways vision can work

unconsciously just a sequence of input

and output which brings up an unsettling

question if blind people unknowingly

respond to things they don't see what

about people who can see do they also

respond to things they're not conscious

of they almost certainly do we all have

unconscious processing going on all the

time but fortunately we usually don't

need to rely on it subconscious sight is

like a superpower we didn't know we had

even when you can't see anything

sometimes you can still see things but

it's not the only sense that we get

subconscious information from smells can

do that too we humans have our noses to

thank for our powerful sense of smell

most of us at least can use our noses to

tell that dinner is ready or that

there's a gas leak it can save our lives

but our noses also do a lot of work that

they don't get as much credit for they

pick up on chemical cues that affect us

on a subconscious level and yet those

cues may play an important role in our

social interactions and our personal

well-being even though we have no idea

it's happening now in the past smell

hasn't gotten much press compared to our

other senses but a lot of recent

research suggests that our sense of

smell is far more important than we

first realized one big clue is that we

humans are pretty smelly compared to our

closest ape relatives and not for

nothing our bo reflects a combination of

factors like our genetics our diet and

our emotional state this can all be

important information and like it or not

our sweat can carry that information

to other members of our species with no

effort on our part when you smell

someone's bo your brain processes the

chemical information it contains and one

thing it can do is influence your

emotions among social species like

humans emotional contagion or the

ability to transmit emotions from one

individual to another through the senses

is common and pretty useful for instance

if one individual sees some danger like

a predator and starts giving off fear

signals others may pick up on those

signals and have a better chance of

protecting themselves plenty of studies

have shown that humans and other social

species transmit emotions through visual

cues like facial expressions and body

language and studies have also shown

that certain animals transmit emotions

like fear through invisible cues in

their scent known as chemo signals so

some scientists wondered how much these

chemo signals might play a role in

emotional contagion among humans in a

2012 study one team of researchers

designed an experiment to find out in it

one set of participants watched videos

that would provoke either fear or

disgust while wearing sweat pads in

their armpits afterward a second set of

participants were asked to smell those

sweatpads and the experimenters recorded

their emotional state conveniently the

emotions of fear and disgust tend to

provoke opposite physical responses when

you're scared your body will typically

try to take in more sensory information

so your face will open up as you breathe

more deeply and scan the environment

with your eyes on the other hand when

you are disgusted you'll generally

reject sensory information like you'll

walk past a row of porta-potties and

you'll scrunch up your face and take

really shallow breaths and look around

less now these reactions aren't always

super visible to the eye but by

monitoring their eyes and facial

movements the researchers could tell

which facial muscles were activated in

each person and which emotional state

their expressions reflected and the

authors found that participants who

sniffed discussed sweat tended to

display disgust which you know seems

like a normal reaction when you're

sniffing sweatpads but also those who

sniffed fear sweat would also display

fear and that's even though they had no

visual or other cues to suggest those

responses what's more they weren't even

consciously aware of the effect the

smell was having on them this suggests

that the subconscious information in

another person's sweat can play an

important role in emotional contagion

and sharing emotions isn't only useful

for protecting against threats in the

environment literally feeling what other

people feel is the basis of empathy

various studies have linked empathy with

what's called pro-social behavior or

behavior that helps other people

basically if we have the capacity to

feel what others feel we are more likely

to look after their well-being so in a

less direct way empathy is also a

survival skill for our species in the

past research has shown how visual cues

can activate our empathy and make us

more likely to help people out but more

recent research has highlighted the fact

that visual cues don't act alone for

instance a 2018 study looked at the role

of chemo signals and making us feel

empathy so get this the researchers used

cotton pads to collect armpit sweat from

a group of 16 participants as they gave

fake presentations that were meant to

intentionally stress them out then the

researchers had a separate group smell

those cotton pads while looking at

pictures of people in different

situations in some pictures the people

were in pain while in others they were

doing something neutral and as the

participants looked at the pictures the

researchers used an eeg to measure the

levels of specific brain waves that

correspond with empathy and they found

that when the subjects looked at

pictures of people in pain they had the

most empathetic response while they were

smelling sweat that contained stress

signals in fact even when the subjects

looked at neutral images they tended to

have an empathetic response if they

smelled the sweat with stress signals

they concluded that emotional contagion

through smell has a strong influence on

our empathy and can sometimes even

override what we see scientists still

don't know exactly what chemicals act as

chemo signals so there's still plenty of

research to be done but what studies so

far have shown is that these signals

that we take in subconsciously are a

really important part of our lives and

we have b.o to thank for the role that

it plays in our well-being and the

well-being of our society so your sense

of smell is linked to empathy who would

have guessed now you've just seen a few

of our videos back to back and you might

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scishow so thanks now on to the next

sentence our perception of our own

bodies is a sense too but one it's

possible to bamboozle you can feel so

connected to an inanimate hand that you

think it's your own hand and respond

accordingly when something hits it let's

go to brit again for that experiment

there's an illusion that's become a kind

of pet experiment that's used all over

the world by psychologists who like

spooking people here's how it goes you

sit at a table and hide one hand behind

a divider with a blanket draped over

your shoulder there's a fake hand on the

table and the experimenter arranges it

so the fake hand's wrist looks like it's

connected to you then you watch the fake

hand as the experimenter strokes both

your hidden real hand and the fake hand

in exactly the same way after a few

seconds you start to get the sense that

the fake hand is actually your own and

that's when the experimenter grabs a

hammer and whacks the fake hand with it

which makes you recoil in panic and yeah

it's kind of mean but this illusion has

actually turned out to be super useful

it's helping programmers create better

virtual realities and it's also being

used in medical treatments the trick is

called the rubber hand illusion and it

was first published by a group of

researchers back in 1998 when they

discovered that if your real hand is

hidden you can convince your brain to

adopt a fake hand as your own there's a

good reason why your brain just

misplaces a part of your body you've

known and loved your entire life it has

to do with multi-sensory integration

when your brain takes information from

all of your senses and puts it together

to create one cohesive picture of the

world usually your brain can do this

really well and your perceptions are

pretty accurate sometimes though the

process can go wrong because your brain

trusts certain kinds of sensory input

more than others when it's building that

big picture in this case it gives more

weight to what you're seeing with your

eyes and feeling with your skin so you

see the fake hand in the spot where your

real hand should be looking like well a

hand and you feel touches that match

what you see happening to the fake hand

your brain trusts that more than your

proprioception the sense telling you

where your hand actually is in space so

it just corrects your proprioception to

match what it thinks is the most

accurate version of what's happening

that's why you feel like the fake hand

is yours even though you know it's not

real and you react to the hammer but the

rubber hand illusion is useful for more

than just scaring people researchers can

also use it to make virtual reality or

vr seem more realistic in a 2010 study

for example computer scientists from

university college london tested whether

the rubber hand illusion would make it

seem more like you'd actually stepped

into a simulated world they had 20

university students use vr headsets and

controllers to experience different

simulations then the researchers

monitored their reactions to the

simulations using both questionnaires

and what's known as galvanic skin

response which measures the intensity of

your emotional responses based on how

much you're sweating they found that

when the simulation included virtual

arms that were in danger of being

injured the player's alertness spiked

they were bracing their own bodies for

impact as if they were actually about to

be hurt but they didn't tend to brace

themselves that way when the simulation

just had plain arrows instead of virtual

arms since this was a small study

there's still a whole lot we don't know

about how the rubber hand illusion

applies to virtual reality but the

experiment has been replicated by other

researchers since then with similar

results studies like this could pave the

way for new techniques and hardware for

more realistic simulations and that

would be useful for more than just

awesome video games realistic immersive

simulations might also help people in

physical therapy since you can have

patients try exercises in ways that

would be impossible in the real world if

you set up a simulation with less

gravity for example and a version of the

rubber hand illusion is already being

used in another kind of therapy called

mirror box therapy it's used to treat

phantom limb pain where people feel pain

from a limb that's been removed as

though it's still a part of their body

phantom limb pain is especially hard to

treat because

there's nothing there mirror box therapy

uses a box with a mirror on it set up to

reflect the patient's remaining limb in

a way that makes it look like the

missing limb is actually there as the

patient looks at the reflection they do

stretches and exercises with their

remaining limb their brain reads what

they're seeing in the mirror as the

missing limb moving stretching and

generally being healthy and turns off

the painful alarm bells dozens of

studies have tested mirror box therapy

and they've found that it does work so

the rubber hand illusion may be a weird

cognitive flaw but by exploiting it we

can create some amazing virtual worlds

and hopefully help people with

rehabilitation and pain too your brain

trusts your sense of vision more than

your sense of touch and it's a

subconscious preference we seem to have

a lot of subconscious responses to food

here's another one fast food was

invented to help us keep up with our

fast-paced world but it's also had some

unintended psychological consequences by

putting us in a hurried mindset fast

food can make us more impatient and not

just in a drive-through line it can

influence our choices and situations

that don't have anything to do with food

and the weirdest thing is it can alter

your behavior even if you're not eating

it just the fact that it's out there can

change your brain unless you know how to

counteract its effects now to

psychologists impatience isn't just not

having any patience we become impatient

when we have a goal but we find out it's

going to cost us more time or effort

than we originally thought to reach it

and that's not always a bad thing

impatience can motivate us to act either

to switch goals or to remove obstacles

to them like if you're stuck in surprise

traffic and need to find a new way home

but it can also cause us to act

impulsively and irrationally so maybe

instead of finding a new route you might

start honking at the cars in front of

you overall this side of impatience can

make us agitated and less happy and fast

food can be part of the problem

psychologists and other researchers have

discovered three big ways our instant

nuggets and dollar tacos are

intensifying our impatience the first

involves a phenomenon called behavioral

priming this happens when exposure to a

stimulus influences a person's behavior

often on a subconscious level

researchers tested this effect in a 2010

study published in psychological science

they primed participants by flashing

fast food logos from restaurants like

mcdonald's and kfc on a screen for 12

milliseconds that's eight times faster

than the blink of an eye and faster than

subjects brains could consciously

register the images still the

researchers found that this unconscious

exposure to fast food symbols ramped up

participants reading speeds by 17

even though the reading test was untimed

and a different experiment from that

study found similar results so just

thinking about fast food made people

more likely to speed up another study

found that fast food also heightens our

impatience by making it harder for us to

stop and smell the roses or the french

fries i guess in 2013 researchers looked

into whether fast food makes people so

impatient that they're less able to

savor life they gave participants a

survey that assessed their ability to

savor experiences then they calculated

the ratio of fast food restaurants to

full service restaurants in each

participant's neighborhood they found

that people who lived in areas with high

concentrations of fast food were less

likely to savor their experiences and

while more research needs to be done on

why the research team hypothesized that

it's the well fast part of fast food

that reminder about hyper efficiency may

keep us from slowing down to appreciate

experiences which might indirectly

affect our happiness too finally it

turns out that this impatience might not

just have an effect on our emotional

well-being but maybe also our finances

in a study published in the journal of

personality and social psychology in

2013 researchers investigated whether

fast food made people more financially

impatient essentially that means people

lost the patience to save money for a

rainy day and in this study they did the

paper found that the more fast food

restaurants a person was surrounded by

the less likely they were to save money

again they didn't even need to eat the

food just standing in front of a fast

food joint elevated people's financial

impatience scientists found that people

outside these eateries are more likely

to accept a smaller gift card in the

moment rather than receive a larger gift

card later and although this study

didn't specifically control for income

others have and the effect still holds

researchers believe this is because fast

food restaurants serve as a subconscious

prime that influences our behavior fast

food is all about saving time so just

being exposed to it could up our

impatience levels and our desire to

choose immediate rewards but good news

just because fast food is everywhere

doesn't mean you're doomed to a life of

checking the clock studies suggest that

we can enhance our patients just by

imagining a future outcome this is due

to the framing effect which happens when

our decisions are influenced by the way

information is presented like in a 2017

study scientists tested how people's

patients levels changed if a question

was framed as a single either or

decision or as a sequence of choices and

consequences that's called sequence

framing so when participants were asked

whether they wanted to get either a

hundred dollars that day or wait 30 days

for 120

they were more likely to choose taking

the money immediately but when

participants were asked whether they'd

rather have a hundred dollars tomorrow

and zero dollars in 30 days or zero

dollars tomorrow and a hundred and

twenty dollars in 30 days they were more

likely to choose the delayed payment

that's because the sequence framing in

the second scenario helped participants

imagine all the choices and consequences

what it would be like at every step in

the timeline and that made them more

patient for the positive outcome so of

all things imagination may be our best

weapon against impatience especially of

the fast food variety so now we've

touched on the psychology of each sense

but maybe not because contrary to what

they told you in elementary school the

five senses don't necessarily encompass

all of our senses the greek philosopher

aristotle used sensory experiences and

body parts to propose that humans have

five senses and you've probably heard of

them before sight smell touch taste and

sound but almost as soon as he proposed

them people noticed things that didn't

fit the bill like when you feel hungry

or dizzy do you sense that through one

of the five senses or is that a separate

sense scientists have debated how many

senses you have for over 2 000 years

because it all comes down to what we

consider a sense scientists classify

senses by distinguishing between

sensation and perception sensation is

all physical it's just the body

detecting a piece of sensory information

what scientists call a stimulus and

perception is organizing and

interpreting that stimulus so a

perception is what we are consciously

aware of for example if you touch a cat

your skin can sense its fur and as this

information gets processed by the brain

you also perceive its softness so

basically sensation is all about the

body perception is all about the brain

neurons sense with tiny receptors that

translate and transfer the electrical

signal generated from physical stimulus

like touching a cat these signals then

get organized and interpreted in

different parts of our brains leading to

our conscious awareness and

understanding of the stimulus like the

softness of the cat's fur and a lot of

the time when people talk about senses

this is what they really mean perception

consciously experiencing or feeling

something so the number of senses that

you have depends on which process

sensation or perception you're taking

into consideration if you think about

the sensory stimuli themselves there

would only be three senses first light

stimuli translates to vision second

chemical stimuli is taste and smell and

third mechanical stimuli account for

touch and hearing then you have

aristotle's original five senses which

were based on perceptions caused by

external stimuli that were detected by

visible sensory organs like your eyes or

nose but there are definitely things

that we can sense that don't have

visible sensory organs attached to them

for example you can sense hot and cold

respectively with your skin but that is

a different thing than touch and we have

a sense of balance through the

vestibular system in your inner ear

which is a detection of motion and

spatial orientation so a definition

requiring external stimuli starts with

these original five and adds temperature

and balance for seven total senses so we

can also feel things that aren't coming

from the outside like pain which is

another sense and of course the source

of pain can be from something external

like a bump or a cut but sometimes it's

a stomachache or a headache with no

external cause there's also

proprioception which lets you sense

movement and where your body is in space

that lets you judge things like how

flexed or extended your limbs are while

doing things like walking if you close

your eyes and let someone move your body

around like a doll you will be able to

describe exactly how you are positioned

without looking because we can sense the

angles of our joints and the length of

our muscles so seven external senses

plus pain and proprioception brings us

up to nine total and nine is the

favorite answer for a lot of

neuroscientists but some people also add

a general category for internal states

like hunger thirst or needing to use the

bathroom so that's 10 senses i guess but

what about things that we can detect but

we're not consciously aware of are those

senses our bodies have receptors for

things like the acidity of our

cerebrospinal fluid and our glucose

levels but we aren't ever aware of

having slightly acidic or basic spinal

fluid you can also break some of the

other senses into more specific

divisions so the category of an internal

state could be broken into each state

individually hunger and thirst would be

two different senses and even needing to

go to the bathroom would be separated

into two senses but also we can detect

the intensity of light and color

independently of each other so maybe

vision is actually two senses so if you

think about senses as stimuli our body

can detect now we're somewhere in the

low 20s but we can go higher we could

think about all of the specialized and

unique kinds of receptors as different

senses vision isn't just broken down

into brightness and color anymore color

is subdivided into different wavelengths

corresponding to red green and blue each

color has a specific kind of receptor

specialized for responding to its

wavelength haste is now salty sweet

bitter sour and umami so now we're up to

33 senses at least because that's not

counting the more than 400 different

types of smell receptors or each

individual auditory receptor that

corresponds with a different pitch so

now we've all lost track but i think

we're in the thousands of senses and

that's just in us humans other animals

like migratory birds can navigate using

the magnetic field of the earth but

ultimately this question is not how many

senses you have but what a sense is

which comes down to perception or how

you make sense of the world surrounding

you which goes way beyond more than just

the original five senses it's not as cut

and dry as we used to think for

something that seems so physical there's

a lot of psychology to how we take in

the world around us thanks for watching

this episode of scishow psych if you'd

like to keep learning about your sense

of sight you might enjoy another

compilation about how you see colors

[Music]

Key Vocabulary

Vocabulary	Meanings
sense /sɛns/ B1	noun - any of the ways in which people or animals are conscious of the world verb - to be aware of something
perception /pərˈsɛpʃən/ B2	noun - the way something is regarded, understood, or interpreted
sound /saʊnd/ A1	noun - something that you hear verb - to make a noise
vision /ˈvɪʒən/ B1	noun - the ability to see
brain /breɪn/ A2	noun - the organ inside the head that controls thought, memory, feeling, and activity
response /rɪˈspɑns/ B1	noun - a reaction to something that has happened
emotion /ɪˈmoʊʃən/ B1	noun - a strong feeling such as love, anger, or sadness
empathy /ˈɛmpəθi/ C1	noun - the ability to understand and share another person's feelings
research /rɪˈsɜrtʃ/ B1	noun - careful study that is done to find out more about a subject
experiment /ɪkˈspɛrɪmənt/ B1	noun - a scientific test that is done to find out what happens in particular conditions
illusion /ɪˈluʒən/ B2	noun - something that appears to be real but is not
reality /riˈæləti/ B1	noun - the state in which something actually exists
subconscious /sʌbˈkɑnʃəs/ C1	adjective - operating or existing outside of consciousness
conscious /ˈkɑnʃəs/ B2	adjective - aware of something
perceive /pərˈsiv/ B2	verb - to notice or become aware of something
influence /ˈɪnfluəns/ B1	noun - the ability to have an effect on the character or behavior of someone or something verb - to have an effect on the way someone thinks or behaves
respond /rɪˈspɑnd/ B1	verb - to react to something
imagine /ɪˈmædʒɪn/ A1	verb - to form an idea or picture in your mind

Key Grammar Structures

• We've only scratched the surface when it comes to decoding the complex ways our senses interact.

  ➔ Present perfect tense + when‑clause

  ➔ The phrase "**We've only scratched** the surface" uses **have + past participle** to show an action that started in the past and is still relevant now.

• It could be pretty big for synesthesia research.

  ➔ Modal verb + base verb (could be)

  ➔ The modal **could** expresses possibility; it is followed by the base verb **be** to form the conditional meaning “might be”.

• The acoustic reflex is well documented in scientific literature and can be used to gain insight into a lot of different hearing conditions.

  ➔ Passive voice + infinitive of purpose (can be used to)

  ➔ The phrase **is well documented** is in the **passive voice**, focusing on the result rather than the agent. **Can be used to** employs the modal **can** plus the passive infinitive **be used** to express purpose.

• They might be able to register where things are moving in their visual field even though it can't see the thing that's moving.

  ➔ Modal verb 'might' + be able to + concessive clause (even though)

  ➔ The modal **might** shows a low degree of certainty. **Be able to** expresses capability. The clause **even though** introduces a contrast, stating a fact that seems contradictory.

• They found that participants who sniffed fear sweat would also display fear.

  ➔ Reported speech with 'that'-clause + modal 'would' for conditional result

  ➔ The verb **found** introduces a **that‑clause** reporting what was discovered. **Would** is a modal used here to describe a likely result in a hypothetical situation.

• If we close our eyes and let someone move our body around like a doll, you will be able to describe exactly how you are positioned without looking.

  ➔ First conditional (if + present simple, will + infinitive)

  ➔ The **if** clause uses the **present simple** (**close**, **let**) to talk about a real possible future situation. The main clause uses **will be able to** to express future ability.

• The brain trusts your sense of vision more than your sense of touch.

  ➔ Comparative structure (more than)

  ➔ The adjective **more** followed by **than** forms a comparative, indicating that the brain gives greater weight to vision than to touch.

• Even though the researchers found that videos showing situations predictive of loud noises trigger veer, the exact mechanisms remain unknown.

  ➔ Concessive clause with 'even though' + present simple passive

  ➔ The concessive conjunction **even though** introduces a contrast between the finding and the fact that the mechanisms are still unknown. The verb **remain** is in the **present simple passive** sense (remain unknown).

• Because we have a sense of balance through the vestibular system in our inner ear, which is a detection of motion and spatial orientation.

  ➔ Causal clause with 'because' + non‑restrictive relative clause (which is)

  ➔ The **because** clause explains the reason for having balance. The **which is** clause is a **non‑restrictive relative clause**, adding extra information about the vestibular system.