Peggy O'Neill Wagner Research Psychologist

Primates Field Operations Manager National Institutes of Health Animal Center

Peggy O'Neill is a Research Psychologist employed by the National Institute of Child Health and Human Development, Laboratory of Comparative Ethology. She has been working in a rehabilitation and research related capacity with nonhuman primates since 1971.

Dear Peggy,


I have a question regarding a seven year old female capuchin. She is a hybrid of Cebus apella and Cebus olivaceus. This capuchin was rejected by her Mother as an infant shortly after birth and was human raised. Her current abnormal behaviors include hyper aggressivity and, characteristic of maturational arrest, a type of autistic rocking with a blanket bunched up between her legs. She will spend much of the day with this blanket, clutching it and laying her head on it while she rocks.

At first, I thought it best to always keep a blanket in with her, even during the warm summer months, thinking that it would give her comfort and, in turn, give her a sense of psychological security. I am now beginning to rethink this practice.


In recent weeks, I have been able to observe a two year old developmentally delayed child from a Russian Orphanage. She sucks the fingers of her left hand. While many children engage in this behavior, it became apparent that when she did this, she would withdraw inward, tuning out the world around her. It has been my observation that this capuchin is very similar. Instead of the blanket giving seeming security and calming the animal, she withdraws from the environment and companions around her. She is seemingly more aggressive towards me as a caregiver when in possession of her blanket, often using it in a combination of chewing and aggressive teeth grinding in displays directed at me. On the other hand, when the blanket is removed for cleaning purposes, she seems to engage herself more in other activities, both lone play/exploration and peer play, grooming and social activity. I am afraid of taking her blanket away on a permanent basis-whether this would be detrimental to her to force her to give up this abnormal behavior. What are your thoughts on this?

Signed, E

Dear E,


You may have answered your own question.

Developmental delay due to lack of stimulation, and or lacking nutrition early in life will have permanent effects, if the brain was not allowed to fully develop. When critical periods end, the ongoing growth, synaptic development stops forever. Cognitive abilities are limited, memory processes are reduced or lacking, and associations needed for learning are impaired or non-existent. The result is an animal or person that simply reacts to incoming sensory input with emotional displays which are basic and usually inappropriate. There are few options for response, thus the impaired individual does the same display over and over, regardless of the new stimulus. I do not know if your animal is impaired in this way. How are the animals' motor abilities? What about vocalizations? Does she appear normal in these other respects? If so, she may lack social skills typical of an adult monkey due to lacking social experience with other monkeys, also required during early development. She would need a non-threatening normal younger peer for companionship in order to learn appropriate social displays.


In addition, if she was raised in a dysfunctional environment where she received positive andnegative feedback that were unpredictable and not consistent with her actions, she could suffer from obsessive and compulsive behavior disorder in order to achieve control, or appear schizophrenic to match the chaotic state of her perceptions. Certain extreme conditions creating severe stress can effect brain chemistry resulting in a whole host of unproductive and unnatural behavior patterns unique to each individual. You will need to provide her with different conditions and simply watch her to see which make her comfortable and which create stress for her. If you like it when she interacts with you calmly and comfortably for long periods, pay attention to her environment. She may have a blanket, perhaps not.


If she cannot sleep without her blanket, then make sure she gets it on a regularly scheduled basis before sleep. Provide dependable routines for her, so she is not upset by surprises. If she behaves better without the blanket, keep it away from her. Perhaps she was terribly spoiled and she behaves the way she does to demand attention. Put her in a sling and carry her everywhere with you to see if she simply has an excessive need for contact comfort. If she was left alone for extended periods during early development she may be severely insecure. See how much of certain conditions she will tolerate. I had a dog once that was seriously abused and thrown off the back of a pickup truck moving at a high rate of speed. He bonded with me and was in terror whenever I was out of his sight. He lived in a constant state of high anxiety. He never had control apparently over the unpredictable and harsh treatment that he received. I allowed him to live out his fantasy and maintain almost continuous contact with myself and the neighbor boys for seven months. Finally he began retreating and seeking independence to play with the other pets. He was actually quite normal after two years of serious positive reinforcement. He lived with me for 10 years and turned out to be the best dog I ever had. Damage done in just a short time early in life can take years to overcome. Check also her diet. Is her behavior related in any way to her feeding schedule or food products? She may suffer from allergies or has a painful toothache which acts up when she eats. That would drive anyone to abnormal behavior. Imagine if you were hungry and needed to eat to survive, but every time you did it hurt so bad, you wish you hadn't.


These are just a few ideas. I wish that I was there so I could come and experience her directly. And by the way. If it turns out that she is afraid of being left alone. You can call on some answering machines and check in with your pets by speaking after the message tone. My pets are very positively responsive to my voice, even if I'm a thousand miles away. If she starts talking back though, better not tell anyone, or they will lock you up!

Let me know how things progress. Patience and a creative imagination are all you need.






To access more information like this Join the SSA today!




For emergency primate help or emergency placement please call:

Debbie Riga


Ann Newman


or email:

Print | Sitemap
© The Simian Society of America, Inc.