Operant conditioning at the NC Zoo Category: Brain & Behavior • News Posted on: September 22, 2008 8:36 AM, by Dave Munger You might think the zoo is an odd place for psychology bloggers to meet up. But on Saturday not only did Greta and I get a chance to connect with some of our readers and fellow bloggers, we also received some fascinating insight into the psychology of zookeeping. Our group toured the North Carolina Zoo, led by Jayne Owen Parker, Ph.D., the Director of Conservation Education of the Zoo Society. As we strolled from exhibit to exhibit and listened to Jayne's comments, we were struck by how frequently psychology enters into the daily routine of managing a zoo. Through operant conditioning, the animals are trained to assist the zookeepers in practically every zoo function, from feeding, to grooming, to medication and contraception. Operant conditioning is simply the use of rewards and punishment to modify behavior, and examples of this process abound at the zoo. When Jim and Nora were younger, we visited the zoo quite regularly, and one of our favorite animals was the elephant (or "Dumbo" as our kids called them). But the NC Zoo provides the elephants with a generous enclosure, and it seemed that every time we visited, they were at the far end of their space, to the consternation of children who wanted to get a close look. Don't elephants like toddlers? On Saturday, we were excited to see an elephant right up near the viewing area: Jayne told us that this wasn't a coincidence. In the last decade, zookeepers realized that their feeding schedule was affecting the elephants' behavior. Every day at closing time, they let the elephants into the barn for feeding. For several hours, as feeding time approached, the hungry pachyderms gradually sidled towards the gate, so they'd get their food as soon as the gate opened. So the zoo placed a new gate near the front of the enclosure, and now at the end of the day the elephants go through that gate and then back through a chute to the barn to get fed. So now the elephants sidle towards the excited zoo visitors in anticipation of dinner, and everyone is happy! (By the way, there's a great article on elephants in this month's National Geographic.) At the elk and bison exhibit, Jayne explained that these animals would be content to remain in their large "prairie" enclosure day and night, year-round, even in rain, snow, and sleet. But the keepers occasionally do need to get the animals into the barn, for instance if a tornado or hurricane is approaching. So they trained all the animals to respond to a sound played over a loudspeaker. Now whenever the sound is played they go to the barn to get a reward. This is done daily, even though it's not strictly necessary, so that the keepers know the animals will respond in an emergency situation. In fact, every animal in the zoo is trained to come to a unique sound, so that they can all be rounded up quickly, or a single species can be isolated as the situation demands. Conditioning, Jayne told us, was a much safer and effective way to care for the animals than older methods like shooting the animals with tranquilizer darts. Even dangerous animals like grizzly bears can be trained to rear up onto a special apparatus, placing their claws and snouts in designated spots, and exposing their razor-sharp teeth for brushing. "The animals love to be trained," she said. The sea lions used to get so excited in anticipation of a training session that their behavior became unnatural for several hours each day, so trainers had to vary the training schedule in order to avoid this problem. For more on the visit and the meetup, check out Bora's post, which includes links to all the other bloggers' posts about the event. (And thanks, Bora, for taking the pictures in this post!) Basic concepts: Reinforcement and punishment Category: Analysis Posted on: August 6, 2007 9:52 AM, by Dave Munger It would be difficult to come up with a more frequently confused concept in psychology than reinforcement and punishment. In fact, "reinforcement" and "punishment" aren't difficult to understand on their own: Reinforcement simply means any means of increasing or encouraging the designated behavior; punishment is any means of inhibiting or decreasing the designated behavior. It was only when B.F. Skinner devised the "positive" and "negative" descriptors that he became the bane of college students for generations to come. Rather than "positive" and "negative," things would have been much simpler if he had used the terms "by adding" and "by removing." The easiest concept to remember is "positive reinforcement." If you want to train a rat to push a lever, you can reward it by offering a food pellet every time the lever is pressed. The rat will learn very quickly to push the lever. This is positive reinforcement, or "reinforcement by adding." But people quickly become confused by the term "negative reinforcement." It's much easier to understand if you think of it as "reinforcement by removing." If the behavior you want to reinforce is pushing a lever, you can also train the rat by removing something when the lever is pushed. For example you could play an annoying sound, and pushing the lever could stop the sound. The rat will quickly learn to press the lever whenever the sound is played. This is negative reinforcement, or "reinforcement by removing." Things get trickier when you talk about punishment, or decreasing a behavior. What is "positive punishment"? It's punishment by adding, remember? Suppose you want to train a rat to stay in one corner of his cage. You could play the annoying sound whenever it is in the wrong part of the cage. This is exactly the way "invisible fences" for dogs work: a sensor on the dog's collar detects the electrical current from the buried wire and plays a high-frequency sound whenever the dog crosses it. Eventually the dog learns to stay in its yard and out of the neighbor's flower bed. This is positive punishment, or "punishment by adding." And what about negative punishment? That's probably the trickiest concept of all. What would "punishment by removing" be? Well, think again about training the rat to stay in one corner. You could attach electrodes to its brain and give it a pleasurable electrical stimulation. Then when it left its corner, you could remove the stimulation -- that's punishment for going to the wrong spot in the cage. With a nice enough stimulation, such as simulating sex, it wouldn't take long to get the rat to stay in its corner all the time. You could also think of this as positive reinforcement: you're rewarding the rat for the desired behavior of staying in its corner. However, the two concepts are different. You couldn't in any way say that the first example of providing food when a rat presses a lever is "negative punishment." Each of these can be effective methods of training, but positive reinforcement seems to get all the good press. Why is that? When used correctly, positive reinforcement can indeed be extremely effective. Rats learn very quickly to press the correct lever if it always results in a food reward; you can even train them to press a lever dozens of times to get a single food pellet. It can also be a great way to teach your kids good behavior: if you give a young child a sticker every time she brushes her teeth, she'll do a lot of tooth- brushing. Punishment, meanwhile -- especially positive punishment -- is discouraged in most child- rearing advice books. Why? If it's effective for training rats and dogs, won't kids learn in the same way? The problem is that children live in a much more complex social environment than dogs and rats. You want your child to stay in his seat at the restaurant, but you also want to talk to your friends. From your perspective, yelling at him when he gets out of his chair is punishment, but from his perspective, that's the only time you're talking to him. While he may not like being yelled at, he prefers it to being ignored, so from the child's perspective, you're not punishing him for getting out of his seat, you're reinforcing that behavior. It would probably be better to reward him for staying in his seat by including him in the conversation, or letting him play with a favorite toy if he stays seated. (Though this second option is problematic because the ultimate goal is for children to stay in their seats and not play with toys in restaurants. Maybe you should just get a baby sitter.) But there are times when punishment is really the only effective way to train your kids. You don't want to use a reward schedule as the only way to prevent dangerous behavior like running into traffic: one mistake can be tragic, and you can't practically reward your child every time she doesn't run out into the street. A time-out when she doesn't listen to your warnings or heads in the wrong direction is probably more effective. Though it sounds "cruel," we have often found very negative punishment to be very effective. If Jim and Nora were fighting over a toy, the quickest way to get them to stop fighting was simply to remove the toy ("punishment by removing"). It didn't take long for them to learn that trying to get a toy by stealing it from your sibling was not effective! ShareThis Comments #1 Alfie Kohn argues against all these behaviorist methods -- particularly rewards -- in his book, Punished be Rewards. The argument is quite compelling: Kohn demonstrates that people actually do inferior work when they are enticed with money, grades, or other incentives. Programs that use rewards to change people's behavior are similarly ineffective over the long run. Promising goodies to children for good behavior can never produce anything more than temporary obedience. In fact, the more we use artificial inducements to motivate people, the more they lose interest in what we're bribing them to do. Rewards turn play into work, and work into drudgery. One example that he gives for this phenomenon is that some parents now offer money (a reward) in exchange for good grades -- but grades are supposed to be the reward. So it seems that you end up in an escalating arms race scenario as the reinforcement loses its appeal and you have to constantly sweeten the deal. This effect is probably more prominent when reinforcement is at the social-isolation/love-withdrawal level than at lower order needs like the food/water/sleep/pain level, but we'd normally consider the latter to be abusive. Posted by: Mike-2 | August 6, 2007 1:13 PM #2 Mike-2, I had to post my first ever comment in order to correct some fallacies in your post. 1. As stated by Dave Munger, it is important to understand the term "reinforcement" and not confuse it with "reward." If the reinforcement is actually "reinforcing," then it must increase the behavior. If it "loses its effectiveness," it does not mean that artificial reinforcement does not work; it means that this particular reward has lost its reinforcing value. 2. In fact, behavior theory predicts this: When reinforcement is presented on a fixed schedule (you get this every single time you do this), it loses its effectiveness and can be easily extinguished. For example, if you get A for every B, then A would eventually lose its reinforcing properties and the frequency of B would decrease. 3. Artificial reinforcement, due to its effectiveness, is often implemented to establish a new or difficult behavior. Once the behavior has been established, the goal is to reduce the frequency/artificiality of the reinforcer. 4. As a behaviorist, I would not recommend that a parent reinforce good grades with money. Instead, I would recommend them to reinforce good study/homework habits using naturally occurring consequences, such TV/computer/phone privileges. 5. There exist a mountain of published data on the effectiveness of reinforcement. I would argue that the examples you provide do not prove that artificial reinforcement does not work. Instead, they're perfect examples of how not understanding the intricacies of reinforcement/punishment may lead to difficulties when implementing these strategies in the real world. Posted by: Terri | August 6, 2007 4:34 PM #3 the examples you provide do not prove that artificial reinforcement does not work. Terri, that's a relief, because I never attempted to say that reinforcement doesn't work. What I am saying is that, assuming that we want our children to grow up to be moral, hard-working and successful adults who think for themselves, helping them learn to develop intrinsic motivations is preferable to a purely behaviorist approach of carrots and sticks, which don't teach anything other than to seek out carrots and avoid sticks. Rewards and punishments may teach a child to mouth the words 'I'm sorry' for hurting someone, but they cannot teach genuine remorse or compassion. Perhaps as a behaviorist, you see no distinction between the two, or simply don't value the inner qualities. That's fine, but for parents who do, behaviorist approaches are inadequate. Posted by: Mike-2 | August 6, 2007 7:32 PM #4 Mike-2, I don't see anything in the post above, or in Terri's comment, that suggests that reinforcement is the only type of learning that occurs in children. In fact, Dave's restaurant example specifically states that a behaviorist approach isn't best in all situations. I'm not sure who's telling you it's the only tool you have as a parent, but they're not on this blog. However, there are some things you might want to teach a child before that child is ready for abstract reasoning. Speech development is one area where reinforcement from parents is huge. Parents who attend to and repeat verbalizations reinforce them. Later reinforcement selectively rewards verbalizations that approximate words, frequently by giving the child whatever (s)he has learned to ask for. It has its place. Posted by: Stephanie Z | August 6, 2007 9:15 PM #5 As it happens I am just beginning to read Kohn's Punished By Rewards, so I too had it in mind reading this article. I'd be very interested to read a review of the book by someone with the appropriate psychological training (who has actually read the book, not just someone's short quotes from it, natch :-) Posted by: Mathematician | August 7, 2007 8:07 AM #6 Stephanie, the overwhelming majority of parenting books focus exclusively on behavior modification. The only serious disagreement is whether certain types of punishment or rewards are more effective -- the traditionalist favoring the former, and the modern, "permissive" parent favoring the latter. This blog post follows those modern parenting assumptions, e.g. "the ultimate goal is for children to stay in their seats and not play with toys in restaurants." To me, the ultimate goal would be for children to be respectful of others when in public places, and behaviorist methods are not helpful for that goal. Posted by: Mike-2 | August 7, 2007 5:31 PM #7 How can you say behaviorist methods aren't helpful for having children behave or be respectful in public places? A quick "I like the way you said thank you to the waiter" is repeating/reinforcing good manners. Also, pointing out how patient and grown up acting a child is when sitting quietly and waiting his turn to speak is another easy bit of positive reinforcing a parent can do while in a restaurant. What it takes is a parent who is attentive to good behavior rather than bad behavior. Behavior modification isn't just about toys, candy and money - those are low level rewards that should be replaced for more subtle, social rewards as soon as possible. Punishment should be used sparingly. Taking a toy away to resolve an argument is fine. Shock collars of any sort should only be used as a last resort. Of course, the less creative and emotionally in control a parent, the more likely they are to resort to punishment. Posted by: guinea pig | August 8, 2007 2:01 PM #8 How can you say behaviorist methods aren't helpful for having children behave or be respectful in public places? I didn't say that. Behaviorist methods can be effective for modifying behavior, they just don't instill the values that most parents would like their children to have. Most people recognize that there's a distinction between merely behaving respectfully and real empathy, and my point is that, by their very nature, behaviorist incentives can't teach empathy. Rewarding empathy is actually counter-productive, because it focuses the child solely on their own needs instead of understanding them in the context of others' needs. Posted by: Mike-2 | August 8, 2007 10:06 PM #9 Guinea pig, you might be interested to read the book, but basically, the argument is that even the kind of apparently innocuous behaviourist methods you mention can, in the long run, *decrease* the likelihood of the behaviour you intend to encourage. Two questions arise: does it really, and why? To answer the first we need experiments, which of course are hard to design well; but many are reported in Kohn's book, with references to the original research. The answers to the second are mostly speculation, but for example, we may suggest that rewarding the child with e.g "I like the way you..." causes the child to pay attention to the praise not the action that elicited it. The action gets reclassified as something which is done to get praise, rather than something which is done for some other reason. That is, the intrinsic motivation for doing the action is actually decreased. I think it's complex, and I don't fully understand the issues: don't mistake me for someone who thinks Kohn reports the One True Answer. I do think it's interesting, though, and a lot chimes with my experience. For example, independently, in my university we are in the process of decreasing the amount of summative assessment (coursework which contributes to the students' final mark) because it is looking as though it's having the opposite effect to that intended: instead of ensuring that students engage with the courses, it's actually stifling their enthusiasm. Of course that's a complex issue too, don't get me wrong! Posted by: Mathematician | August 9, 2007 5:34 AM #10 I really enjoy the discussion and posts on this blog. Everyone here is much more well versed in pyshcology, but I do hear what Mike-2 is getting at. I am hearing that using the behaviorist's approach can change the surface, but it doesn't help change the deep inner truths that we want to teach our children. If that is true, then how would one go about teaching things like empathy, respect, passion, and love? Or are they learned by changing behaviors? Thanks for the great reads everyone. Posted by: The Happy Rock | August 9, 2007 4:46 PM #11 Interesting thoughts, Happy Rock. I remember being taught empathy and respect though I can't say what method was being used. One of my earliest memories is of my dad asking me how I could forget to fill my dog's water bowl because he was totally dependant on me and totally devoted to me. Guilt! I still have an image of that dog looking up at me with big sad eyes and to this day I never forget to fill my dog's water bowl at least once a day. And, Mathematician, I thought we'd be further along with using behaviorism by now. I volunteered briefly doing ABA with autistic toddlers. Some of the things that could be accomplished with these kids by using behaviorial techniques were truly amazing. But I've also observed people working with disabled adults using techniques I considered inappropriate for the situation or sometimes they were just too heavy handed. I guess toddlers are just cuter so people are more motivated to be creative with them. The biggest problem with behaviorism is that it has as much potential for harm as good and can be used as a weapon rather than a teaching method. Posted by: guinea pig | August 9, 2007 9:53 PM #12 I hope this thread isn't completely 'dried up' yet, because it is a discussion I've been looking for. I recently read 'Unconditional Parenting' by Kohn, and previously read 'Punished by Rewards.' I have many questions, both as a parent of four and as a Pediatrician (who regularly dispenses parenting advise for normal as well as developmentally delayed children). It seems that Skinner's behaviourism is pervasive in our culture. Most parents I see (in the rural southeast) use it exclusively. In fact, I notice a strong correlation between old- school 'behavior modification' and strong arm controlling parenting and religiosity. One of the main complaints from these parents about the kids is their 'disrespectfulness' (a hard thing to quantify anyway). Also these parents see Kohn's ideas as simply letting the kids 'run around like wild Indians.' I try to stress the importance of modeling good qualities so that the children learn their value by example, then expecting what has been modeled from them, but not manipulating behaviors via reinforcers. Most people don't get it. The negative effects of controlling parenting techniques are widespread. It starts with night-time sleeping, then picky eater behavior, then potty training. It moves right in to conflicts with older children described above (i.e. behavior in the restaurant, etc). I know it sounds like I'm completely a Kohn supporter, but I do see how reinforcers do things like teach language, but that is subconcious. I'm talking about artificial reinforcers i.e. consequences are engineered by the parents, rather than natural. I think kids respond to being controlled variably. Some may work against the controlling by doing the opposite of the desired action. Some may grow up and become controllers themselves. Any comments on the above incoherant ramblings would be appreciated! Posted by: 7zcata | August 16, 2007 3:57 PM #13 Sorry, the only other comment I wanted to add is that it seems that B.F. Skinner behavior mod. techniques work wonderfully well on autistic children. Is this because they develop abstract thinking later? Is it because our controlling techniques on typically developing children are more subtle but no less utilized? Posted by: 7zcata | August 16, 2007 4:02 PM #14 I probably shouldn't wade too deep into this conversation, but one point I'd like to make is that Skinner's techniques are extremely difficult to implement correctly. Even with rats, experimenters must be highly trained to ensure they aren't rewarding the wrong behavior. As I mention in the original post, the problem isn't so much that Skinner's techniques don't work, it's that all sorts of additional variables are present in a real human environment. Using positive punishment to try to make your child sit in his chair is very difficult to accomplish in real life. Posted by: Dave Munger | August 16, 2007 4:06 PM #15 Dave: so basically, behaviourism may work as a parenting technique, but only if the parent has been trained to PhD level in it? That would explain a lot :-) (I saw a cartoon once with the caption "Children are beautiful behaviourists - and so much better at it than their parents.") 7zcata: could a lot of it be simply that people don't like being controlled by other people - i.e., regardless of how much they like the thing they're doing or the punishment/reward, if they realise that they are being controlled by someone else, they resent it? This feels right to me, and it's consistent with what you say about genuinely natural consequences being better than engineered ones. Then this would imply I think that lacking a fully working theory of mind might stop that resentment, and thereby make behaviourist techniques work better in autistic children (and rats :-) than in neurotypicals. I've never been sure what people mean by "abstract thinking" in this context btw, nor why it should be relevant. Certainly by the time children reach abstract thinking in the Piagetian sense, the parenting-child relationship has an established style - it seems to make little sense to use behaviourism until then, and then switch. Posted by: Mathematician | August 17, 2007 5:12 PM #16 Just because you can, should you? IOW, have you considered if it is morally right to treat children as lab rats? Would you go out to dinner with an adult loved one, and expect that person just to sit there, silent, doing nothing, while you had a conversation with another person? Posted by: basta | September 7, 2007 11:51 AM #17 Basta: Of course it's not a good idea to treat children like rats. For one thing, the cages are much too small (I'm KIDDING). Seriously, though, as I mention several times in the post and comments, trying to get kids to sit still through a meal is a complex and difficult task, and positive punishment is probably not the best way to accomplish it. That doesn't mean that all of Skinner's techniques are bad in all situations. Does anyone have any objection to the strategy of removing a toy when children are fighting over it? That's negative punishment, and if applied properly, it works. We also think it's a good idea to teach kids to sit still at the table, since that's part of having good manners. Including them in the conversation at dinner is an important part of that process, but some of Skinner's techniques can also help.