Placeholder Image

字幕列表 影片播放

  • Here’s a riddle, my Hobbitses: What’s something we all experience, all the time,

  • that we can’t really measure, and barely have words to define? You can’t hold it

  • in your hand, or take a bite out of it. It isn’t something you learn or practice; it

  • just IS.

  • Consciousness. Every science has certain concepts that are

  • so fundamental, yet abstract, that we have a hard time finding the appropriate words

  • to describe them. Ask a physicist and theyll tell you energy and space defy simple definitions.

  • Biologists know if something is alive, but have a harder time explaining what life actually

  • is. Ask a psychologist what consciousness is, and youll getyoull get a slippery

  • answer. For the purposes of this conversation, were

  • going to actually loosely define consciousness as our awareness of ourselves and our environment.

  • It’s this awareness that allows us to take in and organize information from many sources

  • and senses, at once. American psychologist William James thought

  • of consciousness as a continuously moving, shifting, and unbroken stream, hence the term

  • stream of consciousness.” Others think of it as the brain’s roving flashlight,

  • shining down an unbroken beam of light that highlights one thing, and then moves on to

  • the next. The point is, your conscious experience is

  • forever shifting--for example, right now hopefully youre focused on the words coming out of

  • my mouth, but with a little shift - your mind might wander to how you really should shower

  • today, and your chair is uncomfortable, and you suddenly have to pee, and can you believe

  • what Bernice said?!

  • Do I smell pizza?

  • HEY! EYES HERE! WERE LEARNING! Beyond that moment-to-moment shifting, consciousness

  • allows us to contemplate life, think about infinity, and ride a unicycle across a tightrope

  • while juggling melons, at least in theory.

  • Our consciousness helps us plan our futures, consider consequences, and reflect on the

  • past. It is both the most familiar, and the most mysterious part of our lives.

  • It’s kind of like The Force -- but for the little universes inside our heads.

  • [INTRO] Throughout our daily lives we flit back and

  • forth between various states of consciousness, including waking, sleeping, and various altered

  • states. These can occur spontaneously, like dreaming, or be physiologically sparked, like

  • a drug-induced hallucination, or be triggered psychologically, through meditation or hypnosis,

  • for example.

  • Were going to take the next three episodes to look closely at these different states

  • of consciousness, but let’s start with what it really means to be awake.

  • For centuries, scientists learned what they could about the brain solely through clinical

  • observation. And they learned a lot, for sure, but with today’s technology, were actually

  • able to see some of the structures and activity inside a living, working brain - its electrical,

  • metabolic, and magnetic signatures displayed on screens for our wonder and amusement.

  • The field of cognitive neuroscience is the study of how brain activity is linked with

  • our mental processes, including thinking, perception, memory, and language. Like other

  • kinds of neuroscience, it uses neuroimaging technologies to consider links between specific

  • brain states and conscious experiences. And there’s more than one way to scan a

  • brain. Structural imaging shows the brain’s anatomy, and is useful in identifying large-scale

  • tumors, diseases, and injuries. In contrast, functional imaging shows us electromagnetic

  • or metabolic activity in the brain, like blood flow, to let us observe correlations between

  • specific mental functions and activity in particular brain areas.

  • So, yes, neuroimaging has been revolutionizing the field of psychology, much like telescopes

  • and microscopes did for astronomy and biology. But on the other hand, some of this technology

  • is very new, and there’s plenty of disagreement about how to interpret neuroimaging findings.

  • Remember, correlation does not equal causation. So, activity in a certain brain region while

  • having certain kinds of thoughts might be useful to know, but it’s not the end of

  • the conversation. Weve already talked a lot about how function

  • is often localized in the brain and how everything psychological is simultaneously biological--so

  • it stands to reason our thoughts and emotions could in part be illustrated by a bright flare

  • on a dark screen. Weve also collected a fair amount of evidence

  • that we don’t just have one layer of consciousness - a single tape playing various tunes - but

  • rather, something more like two layers, each supported by its own personal bio-psycho-social

  • pit crew. I’m talking about one of the dual process

  • models of consciousness--the idea that our conscious, deliberate mind could be saying,

  • look! a squirrel! while our implicit, automatic mind is simultaneously subprocessing like

  • a computer: color: brown, tail: bushy, movement: climbing, distance: 20 meters, association:

  • my sister had a squirrel phobia as a child, implicit bias: I think that squirrels are

  • ruining America. All of which might weigh upon my behavior upon seeing the little guy.

  • By some estimates, all your senses are scooping up nearly 11 million bits of information,

  • EVERY SECOND. And yet, you consciously register only about 40 at time. So how do we keep focused

  • and filter out all the chatter to actually get stuff done?

  • With selective attention, of course! Selective attention is how we focus our consciousness

  • on one particular stimulus or group of stimuli, effectively tuning out the rest. Your consciousness

  • is like a spotlight on a busy stage. There are other things going on around you that

  • your automatic, subprocessor brain is covertly registering. But for those moments when you

  • shine your spotlight, most of the other stimuli fall away.

  • Try it at home! Right now, youre consciously watching this lesson on consciousness. You

  • probably don’t notice the feel of your socks on your feet, or the tongue that’s inside

  • your mouth, always filling up your mouth with tongue! But as soon as I mention it, the spotlight

  • of your attention turns to them, you feel those socks on your feet, and youre like

  • wow! It’s weird that there’s a tongue in my mouth!

  • The classic auditory example of selective attention is the cocktail party effect. You

  • could be in a room with 47 people jabbering away, and yet be able to concentrate your

  • hearing on one conversation, tuning out the rest of the voices and background music. But,

  • if the couple next to you were to speak your name, suddenly your cognitive radar would

  • light up and your attention would whip around to the sound of your name, probably trying

  • to figure out if Bernice was talking behind your back again.

  • Bernice!!

  • This roving spotlight of selective attention is pretty handy most of the time, for spies

  • and laypeople alike. But it can also be dangerous, if youre being dumb, and say, texting and

  • driving. When you shift your primary selective attention

  • from driving to OMG, LOLOLOLOLOL, you also unwittingly activate your selective inattention,

  • which means that you failed to see that cyclist who you almost ran over, which would not only

  • have ruined her life but also yours so DON’T TEXT AND DRIVE!

  • In fact, when your full attention is directed elsewhere, you’d be astounded by the scope

  • of obvious things you fail to notice. It’s called inattentional blindness.

  • You may have even already been subject to one of the most famous experiments of inattentional

  • blindness...the Invisible Gorilla or, sometimes, the Moonwalking bear. Just google either of

  • those things if you want to be tested on your awareness and then come back.

  • Pretty great, right?! Given the prompt to count the number of passes one team makes,

  • your consciousness is focused on following the players and the ball, nothing else. You

  • don’t see the players in black, theyre the distraction... also you certainly don’t

  • see the dancing gorilla...or bear...whichever one.

  • The original version of this experiment found that about 50% of people didn’t notice that

  • there was A GORILLA WALKING THROUGH THE ROOM!

  • THAT is how powerfully selective our attention can be. Something to remember next time youre

  • behind the wheel.

  • But you know who understands and exploits inattentional blindness better than anyone?

  • Magicians! Except they call it misdirection. Famous modern

  • magician Teller, of Penn and Teller, saysEvery time you perform a magic trick youre

  • engaging in a experimental psychology.” And we can’t help but be rubes.

  • Magicians also prey on our change blindness, the psychological phenomenon in which we fail

  • to notice changes in our environment. And no, I don’t mean climate change. I mean

  • the failure to recognize the difference between what was there a moment ago, versus what is

  • there now. For example, I have changed shirts several

  • times since this lesson started.

  • In a well-known and often-copied experiment, sometimes called theperson swap,” an

  • experimenter will stop someone in a park and ask for directions. And then, during some

  • staged interruption, the original experimenter will leave and be replaced with a totally

  • different person. Half the time, the subject doesn’t even notice.

  • Fun!

  • One of the many perks of studying psychology with me is you learn all kinds of new ways

  • to mess with people!

  • But while change blindness makes for some really cool parlor tricks, this failure to

  • notice certain things can be dangerous -- say, faulty memories lead to false eyewitness testimonies

  • in court, or when friends get deadlocked in a he-said, she-said disagreement.

  • So, my friends, use The Force. But use it wisely. As one of my favorite psychologists

  • once advised: “A Jedi uses the Force for knowledge and defense, never for attack.”

  • Actually, that was Yoda. Anyway, the bottom line is, we are far less

  • aware of what’s going on around us than we think we are. And that’s just when were

  • awake! Imagine what might slip your notice when youre half-asleep, drunk, hypnotized,

  • or hallucinating! That’s what were gonna talk about next time.

  • Thanks for watching this episode of Crash Course, if you were selectively conscious

  • of my words, you got introduced the our constant struggle to define consciousness, learned

  • a little bit about neuroimaging and its developing role in psychological science, how our consciousness

  • is split into two pieces, deliberate and automatic, and how the brain can be selectively attentive,

  • selectively inattentive, and blind to changes in some surprisingly major ways.

  • If you’d like to sponsor an episode of Crash Course Psychology, get a copy of one of our

  • Rorschach prints, and even be animated into an upcoming episode, just go to subbable.com/crashcourse,

  • and subscribe. This episode was written by Kathleen Yale,

  • edited by Blake de Pastino, and our consultant, is Dr. Ranjit Bhagwat. Our director and editor

  • is Nicholas Jenkins, the script supervisor is Michael Aranda who’s also our sound designer,

  • and our graphics team is Thought Café.

Here’s a riddle, my Hobbitses: What’s something we all experience, all the time,

字幕與單字

影片操作 你可以在這邊進行「影片」的調整,以及「字幕」的顯示

B1 中級

意識--心理學速成班 #8 (Consciousness - Crash Course Psychology #8)

  • 310 40
    Ellen 發佈於 2021 年 01 月 14 日
影片單字