Pre- load these (perception)

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1 Pre- load these (perception) ì h"p:// v=vjg698u2mvo&feature=player_embedded ì h"p:// CpKaFCCV2Uz qnjzw&index=6 ì h"p://www2.psych.ubc.ca/~rensink/flicker/download ì h"p:// v=vbpg_obgtwg&feature=related

2 Pre- load these (memory) h"p:// h"p://

3 Cognitive Neuroscience ì

4 What is cognitive neuroscience? ì Cogni&on from Labn: Con (with) + Gnosco (to know) ì Cognibve neuroscience is the study of how our brains allow us to think, perceive, and reason. ì Cognibve neuroscienbsts study things such as a"enbon, learning, memory, percepbon, and decision making.

5 Introducing Memory Memory can be divided into two broad categories: Short- term memory Long- term memory These memory systems rely on different brain systems.

6 Short- term memory ì The magic number for short- term memory is 7±2 items. ì ì Chunking : a technique we use to overcome this limitabon. We chunk phone numbers is not too easy to remember, but is manageable. ì Short- term memory normally lasts only a few seconds. ì But if we keep repeabng what we re trying to remember, we can hold it longer. This is called rehearsal.

7 Long- term memory ì Informabon stored in short- term memory can be transferred to long- term memory. This is called encoding ì This process involves rehearsal, emobonal impact, and fisng the new memory into your network of associabons. ì Unfortunately not a process we have much control over.

8 Memory storage Short- term memory Encoding Long- term memory

9 How is long- term memory stored? ì Case study: HM ì ì In order to cure intractable seizures, surgeons tried a new operabon called a medial temporal lobectomy. This resulted in the removal of the hippocampus.

10 The hippocampus

11 Hippocampus

12

13 What happens without a hippocampus? ì HM recovered from surgery and was ostensibly healthy. But he had serious memory problems. ì HM had good short- term memory, and he could remember everything before the surgery, but he was completely incapable of forming new long- term memories. Anterograde amnesia

14 What does the hippocampus do? ì Judging from HM s condibon, it seems that the hippocampus is cribcal for forming new memories. ì It s not, however, where memories are stored, otherwise HM would have also forgo"en everything he already knew.

15 What doesn t the hippocampus do? ì HM couldn t remember events, at least not explicitly. But he was capable of gesng be"er at tasks through pracbce. Auer daily pracbce, HM was able to get very good at mirror tracing tasks, even though he never remembered having done them.

16 The Psychology of Learning ì

17 Classical Conditioning ì Ivan Pavlov ( ) first described this simple form of learning in dogs. ì Pavlov s dog

18 Classical Conditioning

19 Operant Conditioning ì B.F. Skinner ( ) ì A great innovator in the field of learning. ì Believed that most learning, even in humans, works according to the principles of operant condiboning.

20 See Video The Skinner Box

21 See Video Operant Conditioning

22 Spatial Learning Rats can be placed in mazes to study their spabal memory. The Morris Water Maze is a commonly used test of spabal memory. Rats are placed in a tub full of murky water, and swim about unbl they discover a hidden plaxorm. Later on, they are tested for how quickly they can find that plaxorm again.

23 Spatial Learning ì Spabal learning depends on the hippocampus. ì Rats with hippocampal lesions cannot solve the Morris Water Maze. ì In a famous study, London taxi drivers were shown to have larger hippocampi as a funcbon of their years of experience on the job.

24 Cognition and Perception ì

25 What is perception? ì The five senses deliver the raw material for your brain to process, but your brain needs to do a lot of work to interpret this informabon. ì What you experience is much richer than just what your senses tell you. ì Percepbon is an ill- posed problem

26 Why should the brain take shortcuts? ì The truth is that scienbsts aren t enbrely sure as to why we perceive these illusions. But if the brain makes a mistake, there s usually a good reason for it.

27 The eyes deliver a poor quality image ì Naturally the world we perceive appears crystal clear. But the message coming from the eyes is anything but.

28 The retina is poorly designed Rods and cones are the light- sensing cells of the rebna. Rods: low resolubon, can t see colour. Cones: high resolubon, can see colour. But the rods and cones are at the back of the rebna, behind all kinds of other cells!

29 Only a small part of the eye has good definition Almost all of your cones are concentrated in your fovea. Fovea Blind spot This means that only the fovea has colour vision and high definibon There s also a big spot on your rebna where there are no photoreceptors a blind spot.

30 The bottom line: your eyes deliver a poor quality image. ì Yet we never nobce (usually).

31 The brain has to fill in the blanks ì Because vision is ambiguous, the brain has to do a lot of work in order to make sense of the world. ì The brain has to make assumpbons about things, since it would take too long to test everything.

32 What can illusions teach us about the brain? ì The brain can make do with limited informabon it fills in gaps

33 The whole is more than the sum of its parts

34 Click here to add title ì oh god how did this get in here im not good with computers

35 Which line is longer? The Ponzo illusion

36 Another Ponzo illusion

37 Inferred depth/size Li"le is known about how the brain perceives depth using cues. It is currently believed to involve the visual cortex (occipital lobe) and the parietal lobe.

38 The Ebbinghaus illusion

39 The Ebbinghaus illusion a cross- modal illusion Our eyes seem to tell us that the two orange circles are different sizes. Even though we know they are the same, they sbll look different. What would happen if we made a real- life version of this illusion, and asked a volunteer to grab the orange circle? Would they use the right grip, or would their grip be too big or too small (since their eyes are deceiving them).

40 The Ebbinghaus illusion: cross- modality ì The answer: people use the correct grip size!

41 How the Ebbinghaus illusion works Where pathway Occipital lobe - > Parietal lobe What pathway Occipital lobe - > Temporal lobe Basically, the motor areas of the brain get the correct informabon, but the recognibon areas of the brain get the wrong informabon.

42 Attention ì The world is a busy place. Your brain needs a way to filter out the useless stuff and keep only the important informabon. What do people naturally pay a"enbon to?

43 Attention ì A"enbon is like a spotlight. It helps you see things that are important, and hides the background. Again, the brain gets a very fuzzy picture of the world, and it can t spend forever deciphering the enbre picture. It has to be selecbve.

44 Two flavors of attention ì Top- down a"enbon: ì Paying a"enbon to something on purpose ì Example: Trying to keep focused in class. ì Involves the execubve funcboning in the frontal lobes acbng to direct sensory processing.

45 Can attention fail you? ì What happens if you don t pay a"enbon to something? That s obviously bad. Are there ways a"enbon can be fooled?

46 ì See website. Change blindness

47 What s going on? ì Nobody is quite sure why change blindness happens. But we know some things: ì The brain s visual short- term memory is very limited. It doesn t need to store much informabon since you usually have your eyes open. ì You need to know where to look in order to see a change. The brain can only remember a small part of a picture long enough to look for changes.

48 ì See youtube link Inattentional blindness

49 What s going on? ì Your brain is lazy, and tends to subsbtute past experience for paying a"enbon to things. Ball games don t usually have gorillas, so people ouen don t nobce it. ì Example: Flight simulator study

50 ì See person switch video Some more examples