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Hack 95. Make Yourself Happy
Turn on your affective system by tweaking your face musclesor getting an eyeful of someone else doing the same. Find yourself a pen, preferably a nontoxic, nonleaky one. We're going to use this little item to improve your quality of life and give you a little pleasure. In Action Put the pen between your teeth, in far enough so that it's stretching the edges if your mouth back without being uncomfortable. Feeling weird? Just hold it there for a little, and appraise your level of mood. You should find that you end up feeling just a little happier. If you want to go for the reverse effect, remove the pen (maybe give it a wipe), then trap it between your upper lip and nose like a mustache. If you're feeling anything, it's likely to be a touch of gloom, particularly in contrast to when you had the pen in your mouth. Alternatively, if you're pen-averse, refer to the pictures in [Hack #94] and scrutinize the smiling face for a while. You should find yourself perked upwhile the unhappy photo will likely send you downhill if you stare at it a little. How It Works Emotional expressions are much more than just by-products of our affective system, the system that deals with emotions. Expressions serve as agents that transmit emotions to other individuals and are crucial in creating and maintaining our own emotional experience. And while aspects of this may be conscious and deliberatemy girlfriend may throw me a grin to let me know she's not mad that I've been glued to the computer all evening, and that reassurance will make me happythere is a deeply automatic component. This is termed primitive contagion and is characterized as a three-stage process: it begins with perception, which triggers mimicry, which itself produces emotion. [Hack #94] deals with how we perceive emotions, so here we`ll unpack the other two stages: mimicry and resulting emotion. Mimicry An array of experiments shows that, when emotional faces are presented, subjects produce corresponding facial expressions. For example, subjects can tell from recordings of their faces which emotions they must have been looking at originally. Additionally, facial EMG changes occur after only a few hundred milliseconds: the zygomatic muscles (in the cheeks) used for smiling show more activity after seeing a happy face, while the corrugator muscles (between the eyes, at the top of the nose) used for frowning are more active after viewing anger.
It seems this is something we just can't help. Show emotional faces (photographs in newspapers usually fit the bill) to a friend and look for the flicker of mimicry his face invariably betrays. The stronger the expression portrayed in the picture, the stronger your subject's emotional response. The phenomenon can even be found when a face is shown subliminally Section 9.3 and [Hack #99] and the viewer is unaware of seeing any kind of expressive face; the facial muscles betray the effect. Resulting emotion The act of making an emotional expression has an effect on our emotional state. This has been shown experimentally, most convincingly when the experience is divorced as much as possible from labels like "smiling" (as in the case of pushing back on your lip): simply activating critical muscles produces the effect. This deep coupling to the motor system (a fundamental and ancient function of the brain) underlines the primitive nature of emotions. Direct and automatic feedback means muscular changes make you happier in general without having to invoke concepts of "happy" or a "smile": a joke really is funnier with the pen in your mouth. These stepsobservation, facial mimicry, and finally acquisition of the observed emotionare an effective way of unifying a group of people under one emotion and therefore of marshaling social units to act together. You can see the benefits of having a whole group being scaredaroused and ready for rapid actionif the situation warrants it, rather than some of the group not taking the threat seriously and everyone else trying to convince them. Lengthy persuasion can be avoided given that emotional communication is often automatic. Emotions act as orienting systems, and the adaptive benefit is clear when you consider the importance of rapid mobilization of individuals in a group under certain circumstances: confrontation, escape, or rejection of poisonous food. In Real Life Stand-up comics could learn a thing or two from our exampleperhaps comedy clubs should have a pen-in-mouth policy. The broader point is that, for any communicator, direct visual or aural contact is extremely useful as a means of emotionally orienting an audience. If you want them to be angry, CAPS LOCK WON'T CUT IT relative to a tremor in the voice or a scowl. Similarly, smiles and laughter are contagious. Remote communication can reduce the availability of these cues, although the advent of videoconferencing and other technologies is changing this. Emoticons are a simple attempt to hack into this system, although it remains for the cunning designer to find ever more effective ways of simulating truly contagious emotions. We may also note that women are more facially expressive in response to emotional stimuli, although it is uncertain whether they are also more emotionally affected; one could consider how gender differences could affect social dynamics. See Also · "Left Brain Right Brain" (http://www.abc.net.au/catalyst/stories/s1139554.htm) includes a further experiment you can perform, exploring the relationship between mouth muscles and emotion. · Ulf Dimberg, U., Thunberg, M., & Elmehed, K. (2000). Unconscious facial reactions to emotional facial expressions. Psychological Science 11(1), 86-89. · Wild, B., Erb, M., & Bartels, M. (2001). Are emotions contagious? Evoked emotions while viewing emotionally expressive faces: Quality, quantity, time course and gender differences. Psychiatry Research, 102, 109-124. · Levenson, R. W., Ekman, P., & Friesen, W. V. (1990). Voluntary facial action generates emotion-specific autonomic nervous system activity. Psychophysiology, 27(4), 363-384. Alex Fradera & Disa Sauter
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Hack 96. Reminisce Hot and Cold
 
Find the fire that's cooking your memory systems.
Our emotional system contributes not just to how we respond to the world at a given moment, but how we store representations of what has happened in the past. The makeup of our memories is not decided dispassionately by an impartial documentary reel in our brain, but by passionate, loaded mechanisms that draw out the aspects with the most juice.
10.5.1. In Action
Read the following two tales.1 There will be a quiz at the end of class.
10.5.1.1 Tale 1
"A mother and her son are leaving home in the morning. She is taking him to visit his father's workplace. The father is a laboratory technician at Victory Memorial Hospital. While walking along, the boy sees some wrecked cars in a junkyard, which he finds interesting.
"At the hospital, the staff are preparing for a practice disaster drill, which the boy will watch. Makeup artists were able to create realistic-looking injuries on actors for the drill.
"After the drill, while the father watched the boy, the mother left to phone her other child's preschool. Running a little late, she phones the preschool to tell them she will soon pick up her child. Heading to pick up her child, she hails a taxi at the number 9 bus stop."
10.5.1.2 Tale 2
"A mother and her son are leaving home in the morning. She is taking him to visit his father's workplace. The father is a laboratory technician at Victory Memorial Hospital.
"While crossing the road, the boy is caught in a terrible accident, which critically injures him. At the hospital, the staff prepares the emergency room, to which the boy is rushed. Specialized surgeons were able to reattach the boy's severed feet.
"After the surgery, while the father stayed with the boy, the mother left to phone her other child's preschool. Feeling distraught, she phones the preschool to tell them she will soon pick up her child. Heading to pick up her child, she hails a taxi at the number 9 bus stop."
OK, it's a very easy quiz: which tale stands out more for you? It's likely to be Tale 2.
Cahill and McGaugh's study1 used extended versions of these tales, in order to investigate our current hack: the special status of emotional events in memory. It's generally the second story that is more memorable, particularly the central sectionthis is peculiar because other memory studies indicate that we're typically better at remember events at the beginning and at the end of a story like this. This, along with evidence coming from similar studies, suggests that we have a specialized memory response to emotional stimuli.
The central section of the story isn't more memorable because it contains an unusual emotional event (we remember unusual events better), it's more memorable because of the physical effect emotion has on you. If you did this test while on propranolol, a drug that prevents physiological arousal by blocking beta-adrenergic receptors (preventing increase in heart rate and release of adrenaline), you would find the emotional parts of the story no more memorable than the dull parts. On the flip side, if you were given yohimbine, a drug that increases arousal by stimulating the activity of the adrenaline product norepireprine and so causing a more rapid heart rate, the memory for these sections would be even greater. We don't find it emotional because it is objectively memorable, but it becomes memorable because we are allowed (in the absence of drugs like propanonol) to find it emotional.
10.5.2. How It Works
It's indisputably very useful for the memory system to give special status to events that set off our affective, emotional system. Fearful stimuli, disgusting food sources, kith who have angered youall are elements worth remembering. However, a memory system totally preoccupied with emotional content would constantly disregard the worthy in favor of the frivolous, never retaining any information about currently neutral stimuli (such as food when one is not hungry) when there are more emotional stimuli present. The current best guess is that we resolve this by possessing two memory systemsa "hot" system for dealing with emotional information and a "cool" one for handling neutral content. Increasingly, the evidence suggests that this is instantiated in the brain through a primary memory system built around the hippocampus [Hack #89] for cool content, while hot content is handled in the amygdala, the limbic structure involved in various aspects of emotion processing.
There is evidence to implicate the amygdala in memory.2 Lesions in the amygdala disrupt learninga type of memory that has a motivational, and hence emotional, componentand imaging studies show that greater amygdala activation during the study of emotional information (but not neutral information) is associated with better memory for it. (Interestingly, the lateralization seems to be gender-determined, with different parts of the amygdalaleft and rightbeing used by women and men, respectively.) Epinephrine (adrenaline) enhances memory performance, but only if the amygdala is intact. Finally, patients with amygdalic lesions (the amygdala is damaged) are more poorly conditioned to aversive stimuli; that is, they don't learn to cease behavior that causes them pain.
As the names imply, the hot system is impulsive and quick, producing rapid physical responses (such as a flush of shame) in comparison to the more reflective, contemplative cool system. Current models suggest that that information flows through the hot system in order to reach the cool system, and as a consequence, all input gets cooked: emotional components are amplified and accentuated, potentially at the expense of other details.
The idea that the amygdala is involved in hot, emotional memory is supported by the discovery that the memory boost associated with emotional words doesn't occur if the stria terminalisthis is the connective junction that links the amygdala to the rest of the brainis no longer intact. For example, if this junction is removed, norepinephrine (which is associated with arousal) ceases to produce memory benefits. Similarly, glucocorticoid, a stress hormone, enhances learning if it is plugged into the hippocampus, unless the amygdala is damaged or chemically blocked. So it is clear the amygdala and hippocampus memory systems are not working in isolation.
The evidence that there are two systems at all comes from the differential effects of stress on the two types of memory: increasing arousal always enhances memory for emotional features, but memory for the neutral features (such as context and detail) starts to suffer under high conditions. Seeing one change (an increase of arousal) have two different effects is good evidence for multiple systems.
10.5.3. In Real Life
Apart from our own observations that emotionally charged events will be memorable (to the point where it is difficult to imagine how it could be otherwise), the most powerful example of the preoccupation with emotion designed into our memory systems is post-traumatic stress disorder (PTSD).3 Individuals suffering from PTSD experience flashbacks, the intrusion of imagery and memories from or related to the traumatic events that typically produced the condition. The worse the trauma, the more likely that PTSD will result, and sufferers have consistently higher resting heart rate and blood pressure, relative to a comparable group.
It is established that PTSD patients have smaller hippocampal volumes, although it is not clear whether the traumatic stress reduces the hippocampus or whether smaller hippocampi are a risk factor for PTSD. These individuals show poorer general memory performance, and while the flashbacks themselves are full of vivid detail, they are often gappy and the patients show inability to actively recall any other details besides those that impose themselves upon them. This would fit with the two-systems theory: the flashbacks themselves have well-coded (or "hyperencoded") emotional content, but the stress precluded the recording of further detail. While the emotional content comes easily to mind, their general high level of stress, possibly coupled with suboptimal transfer from the hot to cool systems, produces poorer memory for the cold, neutral information.
10.5.4. End Notes
1. Reprinted and abridged from Consciousness and Cognition, Vol 4, No 4, Cahill, L., & McGaugh, J., "A Novel Demonstration of Enhanced Memory Associated with Emotional Arousal," pages 410-421, Copyright (1995), with permission from Elsevier.
2. A good book to get a full picture of amygdala, learning, and memory: LeDoux, J. (1996) The Emotional Brain: The Mysterious Underpinnings of Emotional Life. New York: Simon & Schuster.
3. The Post-Traumatic Stress Disorder Alliance (http://www.ptsdalliance.org/home2.html) hosts educational resources on this condition.
10.5.5. See Also
· "How Brain Gives Special Resonance to Emotional Memories" (http://www.sciencedaily.com/releases/2004/06/040610081107.htm).
Alex Fradera & Disa Sauter
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Hack 97. Look Where I'm Looking
We are innately programmed to follow other people's eye gaze to see what they are looking at. It's so deeply ingrained that even cartoon eyes can interfere with our mental processing of direction.
Eyes are special. They're part of a two-way sense. Wherever I look, you can tell what I'm looking at. You can tell if I'm paying attention to you or not, as well as hazarding a good guess as to what I'm really thinking about. Following gaze isn't a learned behavior. As far as the brain's concerned, gaze direction is a first-class citizen of the real world, as important as location. In the case of location, the Simon Effect [Hack #56] demonstrates that we have a tendency to react to a prompt in the same direction as that stimulus. This hack shows that we interpret gaze direction in much the same way as location: a cartoon pair of eyes looking in one direction has the same effect.
10.6.1. In Action
A team at the University of Padua in Italy constructed an experiment to see the effect of gaze.1 They drew a pair of cartoon eyesjust two ovals with a colored oval (the iris) within each, as shown in Figure 10-5. The irises were colored either blue or green, and the cartoon could be looking either straight ahead or to one of the sides.
Figure 10-5. Cartoon eyes similar to the ones used in the experiment: show this page to someone and watch what her eyes dosee if you can catch her just flicking off to the right as the cartoon eyes trigger her automatic gaze-following routine
People taking part in the experiment had to report the color of the irises, hitting a button on the left for blue and on the right for green. The apparent gaze direction wasn't important at all. Despite that, it was faster to hit the button for green on the right when the eyes were looking the same way (to the right) and slower when they were looking the other way. The same held true for blue and the eyes looking left.
Thinking this might be nothing to do with the ovals looking like eyes, to investigate further, the team put together another task. Instead of ovals, the cartoon "eyes" were squares, with square "irises" in each, and looked much less like eyes (as shown in Figure 10-6). And sure enough, the significant reaction time difference (between gaze pointing in the same direction as the response key and in the opposite direction) went away.
Figure 10-6. Square "eyes" similar to the ones used in the experiment: we don't follow the gaze of robot eyes
It's possible this is why the X Windows toy "xeyes," which puts a pair of eyes on your computer desktop that follow your mouse cursor around, is so uncannily handy for avoiding losing your pointer.2
R.D.
10.6.2. How It Works
Essentially, this experiment shares a mechanism with the Simon Effect [Hack #56] . Given that the brain translates gaze direction into location, the same effect gets triggered: if attention has already been directed to the left because of the stimulus, it takes a very short time more to make a response on the right.
It makes sense that we treat gaze with such respect. If someone's looking at us, it usually means that some kind of interaction, for good or ill, is in motion. And if there are a few people looking at the same place, they've probably spotted something you should know about. Gaze is physically so tiny, but figures large in our social world. Just think how it feels to make eye contact with a stranger (sometimes good, sometimes embarrassing) or how difficult it is to have a conversation with someone looking elsewhere. If you doubt this, try repeatedly glancing over somebody's shoulder while you're talking with him, and see how long it takes him to crossly ask you what you're up to or glance over his shoulder to see what you're looking at.
I've a suspicion that this is why arrows work so well as symbols. Given we can look at cartoons of eyes and still follow gaze, how reduced can that cartoon get and still work? OK, it doesn't work with square eyes, but the salient features of eyes are that they're long and pupils go into the corner and pick up an arrowhead shape when they're looking off to the side. Just like an arrow, in factwhich leaves me wondering whether arrows (in print, in signage, and everywhere) are very good learned symbols or whether they tap into something deeper.
M.W.
This deep gaze perception is also sometimes referred to as shared, or joint, attention. The use of two people paying attention to the same object is most obvious for infants. When infants are learning, they need to be able to make associations between objects, words, actions, and so on. If there were no way to point or direct an infant's attention, it'd be next to impossible to teach her anything. At about 12-18 months, children follow eye gaze: they can observe your eyes, tell what you're looking at, and look over there instead. It's this automatic mechanism of joint attention that is used in making a shared understanding of the world.3
Pointing performs much the same function as gaze, indicating where to pay attention. Of course, this doesn't work for dogs, as is well-known by anyone who's tried pointing as a way to get a dog to look somewhereonly to have the animal stare at the end of the pointing finger. The only way to teach association for dogs, who don't understand such abstract symbols as pointing, is to wait until they're paying attention to whatever you want to teach them about anyway and then do whatever you were going to do. It could be argued that our real defining characteristic, as humans, is the ability to understand the symbol "that." Without it, we wouldn't be able to talk about objects that aren't present, and wouldn't be able to learn from other people's mistakes.
(Some dog lovers may disagree, but then this is what makes them dog lovers, isn't it?)
M.W.
Shared attention is one thing that infants use as a springboard to develop an understanding of other minds, not just the world of objects. Children with autismindividuals with an impaired understanding of other people's intentionsdon't follow gaze automatically as other children do.
10.6.3. In Real Life
The effortless, rapid, almost unconscious encoding of gaze direction makes it an ideal social signal, which, of course, leaves it open for abuse. Spot how many advertisements have a large face with eyes directed exactly at what they want you to read.
10.6.4. End Notes
1. Zorzi, M., Mapelli, D., Rusconi, E., & Umlità, C. (2003). Automatic spatial coding of perceived gaze direction is revealed by the Simon Effect. Psychonomic Bulletin & Review, 10(2), 423-429.
2. Lowcoders have written a Mac OS X clone of xeyes, called iEyes (http://www.lowcoders.net).
3. Driver, J., Davis, G., Ricciardelli, P., Kidd, P., Maxwell, E., & Baron-Cohen, S. (1999). Gaze perception triggers reflexive visuospatial orienting. Visual Cognition, 6(5), 509-540.
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Date: 2015-12-11; view: 637
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