Learning To Blog & Blogging To Learn

Blog With Me?

As the holiday season rolls in full swing and the festivities begin, Christmas decorations become delightfully impossible to avoid.  Snowmen, gingerbread families, doves, and penguins seem to pop-up everywhere amongst decorated Christmas trees, wreaths, and lights.  To keep with the spirit of the season, my blog this week will revolve around those mini-tuxedo dawning creatures, the penguins.

During three months out of the year, king penguins alternate care duties on land with foraging trips on the sea between mates.  However, king penguins live in extremely large colonies consisting of anywhere from a few hundred to 500,000 mating pairs, which poses a major problem.  Upon returning from sea, finding a single penguin in such a massively dense crowd, about 2.2 breeders per square meter, seems nearly impossible.  To make matters more difficult, king penguins lack a nest.  Instead, the mate on land incubates the egg on his feet, allowing him to move within the colony during storms or disputes with neighbors.  The resulting “short distance movement [. . .] creates an important problem in relocating one’s mate” (Lengagne et al., 1999).  The work of Lengagne, Jouventin, and Aubin aimed to study how penguins are able to handle such a problem and have found that the “difficulty in relocating mates posed by wandering incubation has been partially solved by the use of acoustic signals” (Lengagne et al., 1999).  Acoustic calls are first produced by the returning penguin as he aims to identify his mate.  His mate calls in reply, providing more information on her location within the colony.  They repeat this process until they are reunited.  In addition to the aforementioned, each pair faces difficulties due to their environment.  Not only do windy and snowy conditions drown out and degrade the sound of their calls, but the background noises due to conspecific calls with similar temporal and spectral characteristics from other calling penguins generate an extreme jamming effect.

Lengagne et al. observed 28 pairs marked for individual identification from the laying of their egg to the end of the brooding stage (when both parents leave the chick to forage for food).  The calls of each individual of interest were recorded.  While one of the penguins were out foraging for food, the calls of that absent penguin were played to its mate at a distance of 20, 15, 14, 13, 12, 11, 10, 9, 8, and 7 meters away in a randomized fashion.  It is important to note that the calls were played back in the morning during calm and dry weather.  They then noted the response of the penguin and categorized them either as positive (where the penguin calls in reply to the broadcast signal of its absent mate, interpreted as recognition of its mate’s signal) or negative (where there is no vocal response and the penguin fails to reply, interpreted as failure to discriminate the broadcast signal of its absent mate).  They also observed what they termed the Distance of First Emission, or the distance between the two penguins at the beginning of the acoustic search when the first call by the returning penguin was made.  They kept track of the Number of Display Calls emitted by the Arriving and Incubating penguins, termed NCA and NCI, in addition to the Time Delay, or the time taken between the first call of the arriving penguin and the moment of unification.

Lengagne et al. found that 71% of the incubating or brooding penguins moved, on average, a distance of 4.4 meters while their mate was away foraging (total, combining the results from both the incubating and brooding stages).  Transforming this linear distance into the maximum radius of circular areas produced an area of presence of 65.7 meters squared.  Within this area, the number of mating pairs was estimated to about 145.

Image

They also found the average discrimination distance to be 8.8 meters such that at 8.8 meters, the penguins called back in response to their returning mate indicating that there was recognition of the initial call.

Image

Image

The average distance between the two penguins when the returning penguin made his first call was 8.3 meters.

Lengagne et al. found that there were strong correlations between Time Delay and the DFE, between the NCA and DFE, and the NCA and Time Delay.

ImageImageImage

The data showed that the returning penguins called an average of 5 times over an average time of 114 seconds to reunite with its partner, and 70.17% of the time, its partner was able to discriminate the very first call of the returning penguin.

Lengagne et al. discuss how the efficiency of these uniting calls is accomplished.  The returning penguin “progresses silently towards a preferred area of the colony, named the attachment zone, probably using topographic cues” then starts its acoustic search (Lengagne et al., 1999).  However, because the individually specific calls propagates among the bodies and background noise of thousands of penguins, the broadcast distance is reduced, the signal degrades, and masking effects alter the frequency and temporal domains of the calls, which all ultimately impairs the communication process.  However, the fact that the majority of the incubating king penguins discriminate their incoming mates at their first emission implies that acoustic communication is a particularly efficient strategy in this species” (Lengagne et al., 1999).

One thing to bring up, though, is the distinction limitation of observing performance.  Just because the penguin does not respond to the returning bird (negative response) does not mean that it does not recognize its partners call.  Maybe the penguins hear their mates’ calls, however it takes energy to call back out to them (they don’t have much energy taken that they haven’t eaten for so long while their mates are out obtaining food).  Therefore, even if they hear that their mate is far away, they could wait a little longer until they know their mate is close enough so it is more likely they will be reunited.  It could be argued that this increases efficiency and energy utilization.  In addition, there is a difference between hearing their mates call as opposed to recognizing it.  The distance of 8.8 meters relates to a clear, calm, and dry environment where the main variable would be recognition.  However, if the environment were snowy or windy, it becomes an issue of whether or not the penguins can even hear each other in the first place.

Another thing of discussion revolves around their methods.  At what loudness did they play back the calls?  Although they played the calls at set distances, maybe the loudness they played it out actually corresponded to a different distance.  For example, if they played the recorded call back too loudly, having the speaker 11 meters away could actually be interpreted as the penguin being only 9 meters away.

Lengagne et al. looked at how far away the returning bird is from the brooding penguin once the brooding penguin calls back, indicating recognition by the brooding penguin.  However, I am curious to know if this is the same distance required for the returning bird to recognize the calls of the brooding bird.  Maybe there is something about moving around (by the returning penguin) that makes it different when compared to staying in one general location (the brooding penguin) in regards to hearing and recognizing calls.  When all is said and done, however, this is still an amazing feat penguins accomplish each year.

To obtain a better understanding of the difficult situation penguins are faced with, please see the following video at 1:00 (1:00 on will show you how noisy and crowded the colonies are):

Attached are some pictures illustrating just how densely populated the penguin colonies are.  The difficulties of finding ones mate can further be appreciated.

Lengagne, T., Jouventin, P., & Aubin, T. (1999). Finding one’s mate in a king penguin colony: efficiency of acoustic communication. Behaviour, 833-846.

So far, we have…

So far, we have only looked at studies that used positive reinforcement to achieve behavior that is something positive for both the subject and those around him or her.  This week, we will look at how positive reinforcement can actually produce and increase behavior that may be harmful and even lead to one’s detriment.  In the article by Billings et al. we see a study on how “reinforcement can induce children to falsely implicate themselves in wrongdoing” (Billings et al. 125).  Their verbal behavior can be manipulated and shaped such that the accuracy of their statements is greatly reduced.  Depending on how an interview is conducted, an interviewer can induce false accusations and confessions of wrongdoings.  Additionally, these results are robust such that the children “continue to affirm their accusations even when challenged” later on (Billings et al. 126).  First let’s look at how such a phenomenon is achieved.  We will then look at why this phenomenon may occur.

Ninety-nine 5 to 9-year-olds are introduced to and are allowed to play with a colorful toy in their elementary school.  After a span of three days, the experimenters remove the toy and claim that someone has taken the toy, probably just to play with it.  They explain that they believe a student is responsible and that they need the children’s help to find out what has happened to it and who has taken it.  Each child is then taken separately to be interviewed and is questioned in a “warm, supportive way” (Billings et al. 128).  The experimenters manipulate how the children are interviewed such that the control group of children are asked straightforward suggestive questions while the reinforcement group children are approached with the same suggestive questions but with an addition of reinforcement after every question answered with a “yes.”  Reinforcement includes verbal responses such as “Thanks!” “Great!” “You’re being a real help.” 

There are five groups of interview questions:

1) Filler Question: these questions are expected to produce a “yes” answer.  (“Do you remember the Brain Warp toy?”)

2) Guilty Knowledge Questions: these questions ask for information the child cannot possess unless he or she is present when the toy is taken.  (“When the kids took the toy, did the toy make a loud noise?”)

3) Direct Witnessing Questions: these questions ask if the child has directly observed the toy as it is taken.  (“Did you see the kids take the toy?”)

4) confession Questions: these questions ask if the child has personally participated in the taking of the toy.  (“Did you help another kid take the toy?”)

5) Leading correct Questions: these questions ask the child for information that the child does in fact possess.  (“Did the toy have different colors?”)

The Guilty Knowledge, Direct Witnessing, and Confession questions are classified as the misleading questions that are potentially self-incriminating.  Results are calculated based on the percentage of times the children answer “yes,” either verbally or nonverbally, to one of these three categories of questions.  Billings et al. find that the simple reinforcement tactics can in fact “induce children to make false incriminating admissions against themselves” such that 52% falsely admit to guilty knowledge concerting the theft, 30% falsely admit to witnessing it, and 18% falsely confess to participating to the theft with their corresponding control group counterparts resulting in 36%, 10%, and 6% respectively (Billings et al. 133).

Billings et al. also find that “conversations with teachers afterwards [indicate] that the children generally [enjoy] being questioned, even though from a strictly legal viewpoint, they [implicate] themselves in an apparent theft” (Billings et al. 133).  Why then are children willing to admit to being part of or being responsible for something negative which may give rise to punishment?  Their sense of enjoyment may stem from the fact that this type of reinforcement causes them to feel like they are doing something praiseworthy and honorable at the immediate time frame. In this experiment, it is important to Billings et al. that everything is conducted such that the children have a positive frame of mind and lack any anxiety.  Although they are admitting to something that is condoned, they are more focused on their prevalent actions which are prompting praise.  Or it could be that due to their limited experience, the children may be failing to recognize that “by making false claims of guilty knowledge or direct witnessing, they [are] thereby implicating themselves in the theft” (Billings et al. 134).  Instead, they think that they are just helping and are not realizing the ramifications of their claims.  It could also be that they do understand the consequences and are paying attention to both, but merely outweigh the “negative utility of possible self-incrimination [with] the positive utility of receiving praise and approval from the interviewer” (Billings et al. 135).  They lack the ability to forego the immediate positive consequences to avoid the more remote negative consequences.

The reason that this is so important is because Billings et al. mention additional studies of adults and adolescents that find similar results.  Positive reinforcement and feedback can “induce adult eyewitnesses to make inaccurate statements or report false memories.  Older individuals will sometimes even make false self-accusations in response to social pressure and other influences” (Billings et al. 126-127).  Although the type of reinforcement and tactics used must differ slightly due to the age differences, this phenomenon still persists.  In regards to our legal systems, the consequences for an individual therefore can heavily depend on the interrogation and interview process and the level of experience each individual has.  How much conscious control do we actually have then of our outcomes and present situations?  In this study, “gentle tactics [. . .] are able to extract self-incrimination admissions from children and even several full confessions in a matter of a few minutes” (Billings et al. 136).  Emphasis must be placed on the gentleness of these techniques and the fast manner in which they work.  While being questioned, one may not realize how bad a situation they are getting into since the process may seem so demure and safe due to the positive aspect of the rewards.  In addition, one may think that nothing consequential can result from a questioning of only a few minutes.  This type of positive reinforcement therefore is an enemy in disguise that is harder to reveal than if being interrogated in a harsh, accusatory manner.  The limitation for this study, however, is that the crime is a theft-crime.  If the crime is instead something more serious, such as breaking the toy, will the results change? 

In closing, it is also important to mention of a case where this phenomenon actually happened.  In 1998, a 7-year-old and 8-year-old boy were charged for first-degree murder after admitting to killing an 11-year-old girl.  Luckily, evidence proved that they could not have possibly been the killers and the charges were dropped.  Investigators believed that the interviewers were responsible for the inaccuracies of the boys’ confessions.    The interviewers bought the children a Happy Meal and reminded them that “good boys tell the truth [. . .] held their hands, told them they were friends, and questioned them about the murder” (Billings et al. 126).  These things could all be seen as positive reinforcement and could have easily manipulated the boys’ statements.

 

Billings, F., Taylor, T., Burns, J., Corey, D., Garven, S., & Wood, J. (2006) Can reinforcement induce children to falsely incriminate themselves? American Psychology, 31, 125-139.

What happens when you introduce something to look forward to in a situation that is bleak and both a psychological and physiological struggle?  This can be the difference that allows for motivation to adhere to treatment regimens for those with medical difficulties.  In fact, the two articles we will discuss this week look at methods for improving adherence to treatment of chronic diseases in children via positive reinforcement.  The importance from these studies stem from the fact that poor adherence is a common problem which, in many cases, is the underlying cause of poor clinical outcomes. Therefore, this may “lead to misconceptions regarding the efficacy of the treatment,” sometimes creating what merely “appears to be a ‘treatment resistant’ disease” (Luersen et al. 5).  The treatment is then perceived to be the problem when, in actuality, the problem is the patient’s willingness to faithfully and correctly stick to the treatment.

Luersen et al. look at this problem of variable adherence and it’s importance as a factor in clinical outcomes.  They review other studies which implement sticker charts to instrumentally train children with chronic diseases to adhere to their respective treatment regimens.  Each time the child completes their specific treatment or reach specified intake levels of substances, the child receives a sticker.  This type of positive reinforcement via the application of a sticker is thought to do two things: (1) It provides the children with an immediate sense of gratification and (2) It helps remind the children (and parents in some cases) whether a treatment has been completed and when the next dose is due.  I will lightly touch upon the studies Luersen et al. focus on but please feel free to look into the specifics involved at http://onlinelibrary.wiley.com/doi/10.1111/j.1525-1470.2012.01741.x/pdf.  Following is an example of a sticker chart:

Image

In a study by Stark et al., 4-12 years old cystic fibrosis patients are rewarded with a sticker each time a calorie goal is met. When compared to control groups, results include greater increase in caloric intake, weight gain, and BMI which was maintained during follow-up testings.

In another study by Stark et al., 4-10 year old juvenile rheumatoid arthritis patients are rewarded in a stepwise fashion with one sticker per increase in calcium intake per meal and for meeting specified calcium goals.  When compared to control groups, results include an increased calcium adherence and greater body bone mass.  Patients 5-12 years old with inflammatory bowel disease also participate in this same type of sticker program which similarly results in an increase in calcium intake and a greater percentage of patients achieving their set calcium goals.

The study of Cass et al. involve tuberculosis patients who are 1-14 years of age.  The introduction of sticker charts in which they are rewarded one sticker for each daily tuberculosis medication ingested makes children 2.4 times more likely to complete their latent tuberculosis infection treatment.

Slifer et al. study 3-5 year old patients with breathing disorders and how the sticker charts increase nightly BiPAP (Bilevel positive airway pressure) use.

In a study by Penica et al., a 2 year old hemophiliac child is rewarded with a sticker for adherence during the IV infusion of clotting factors.  This results in both the decrease in negative behavior and increase in positive behavior during the infusion process.

Luersen et al. findings therefore support their claim that the sticker charts are effective at increasing adherence to therapy in children with chronic disease.  Moreover, the effect is robust, working across a wide variety of chronic pediatric diseases.  What’s important about this is that these interventions improved the clinical outcomes, which is the ultimate goal of the adherence modifying methods.  What is the reason for the apparent success of this approach?  One can speculate that introducing a reward program gives the patients something to look forward to and want to work for.  It is something positive in their already adverse and tiresome life.  Medical difficulties, especially chronic diseases, not only burden the body but also have significant psychological ramifications.  It is not normal for a child to have to go through the demanding treatments, to be restricted from everyday activities, to be constantly worrying about their health.  Therefore, giving them some kind of encouragement, something rewarding, something positive is extremely important.  The desire to adhere to their treatments is instilled through this instrumental positive reward.

To further understand this type of instrumental conditioning, specifically positive reinforcement, let us now go in depth into one of the studies which results in similar findings as the studies above. This four patient study by Magrab et al. include one 11-year old, two 13-year olds, and one 18 year-old, all of whom are in the pediatric hemodialysis unit receiving dialysis treatment 2-3 times a week.  A serious problem among all four subjects, which is actually common for many pediatric patients undergoing dialysis treatment due to renal failure, is adherence to strict dietary restrictions.  Failure to follow the prescribed diets results in “increase risk for fluid overload and congestive heart failure, hypertension, hyperkalemia, azotemia, and bone disease” (Magreb et al. 573).  Because few techniques are found to be successful at maintaining compliance to the dietary restrictions, Magrab et al. wish to test the success of a token economy on these type of patients.  Their token economy is a bit different than the conventional in that only reinforcement is delivered (never is anything taken away).  In order to receive a reinforcement of 2-3 points, weight gain between dialysis sessions must be equal to or less than 2 pounds.  Weight gain is used as a measure of fluid intake, and 2 pounds represents the largest amount of fluid safe for dialysis.  Eighteen points are equivalent to $2.00 for purchasing prizes or rewards.  What is unique about the specific reward system of this study when compared to the previous studies discussed is that it is a “specially for you” system.  The children are allowed to construct their own prize list and indicate specifically what rewards the want to work for (as long as it is not food).  In addition, a chart which records their respective point achievements is posted in a very visual location in the unit for further motivation and recognition.  Each week the child’s point count is gathered, and he or she is allowed to exchange the earned points for their predetermined prizes.

Thankfully, the results of Magrab et al. are promising.  Compared to the baseline data, a reduction in the amount of weight gained found is found between dialysis sessions such that the average baseline gain is 2.18 lbs while the average treatment gain is .97 lbs.  In addition, a substantial change in the percentage of sessions in which the patients exceed acceptable weight gains decreases from a baseline of 47% to 20% during treatment.  It is also noticed that any extreme weight fluctuation that occurs during baseline is reduced during treatment.

Again, it can be hypothesized that the reason why this type of reward system is successful is because many psychosocial adjustments must be made when one is ill and “severe restrictions or major changes in eating style may become further barriers to normal social activity” (Magrab et al. 573).  Therefore, many more negative things are introduced into the lives of these patients.  By introducing something positive, these children have something to look forward to, something to work for.  This essentially enhances the quality of their lives and provides a type of “life motivation” (Magrab et al. 578).  A reward system can also give the patients a sense of control over something in a situation they have little control over.  They gain a sense of power over their present states.  Moreover, the special thing about this case is that the children are able to choose exactly what they want their reward to be.  This then tweaks the system so that the motivation to complete the task, to adhere to their dietary restrictions, is greatest.  In the other studies, the value of stickers may be different from one patient to another.  However, in this study, the value of the reward is high for all patients.

 

Magrab, P. R. & Papadopoulou, Z. L. (1977) The effect of a token economy on dietary compliance for children on hemodialysis. Journal of Applied Behavior Analysis, 10(4), 573-578.

 

Luersen, K., Davis, S., Kaplan, S., Abel, T., Winchester, W., & Feldman, S. (2012) Sticker charts: A method for improving adherence to treatment of chronic diseases in children. Pediatric Dermatology, 1-6.