In Brief

Chimpanzees who have early cultural experiences with humans may develop the brain capacity for paying better attention to conceptual and memory tasks, according to research presented by Ohio State University psychologist Sally Boysen, PhD, at APA's 2003 Annual Convention.

Her research suggests that cognitive differences may exist between chimpanzees raised in a structured human environment with constant, nurturing communication from caretakers--called enculturation--and chimpanzees that grew up in the wild or in lab environments without enrichment. Chimps whose formative years included interactive teaching techniques such as looking at picture books and playing naming games probably develop more enhanced neural pathways, especially in their frontal lobes, Boysen therorized. Such development allows them to attend significantly better to the communicative features of human interactions and to reference human gestures and other dialogue-like systems used by their teachers.

"We're bringing chimpanzees who already have a huge cognitive capacity into a rich cultural environment, and they just blossom," said Boysen, who has worked with chimps for 30 years--even raising some of the babies in her home.

When chimps are taught at a young age how to interact with humans, their brains form new neural pathways, a greater number of dendritic connections and heavier frontal lobes, Boysen conjectured--a hard theory to test because squirmy chimps don't cooperate well in MRI machines. That prep work of interacting with humans is what allows them to, later in life, perform startlingly complex tasks like numerical processing, including counting objects and adding their quantities, as well as learning to use written English words and letters with a touch-screen computer.

But enculturation has to happen early in life, from birth to 3 or 4 years old, Boysen said. Otherwise, chimps raised in the wild or an unsocialized laboratory setting never develop the executive brain function to attend to the critical features of a problem-solving situation or conceptual task. "You can't teach an old chimp to pay attention," she explained.

From studying this type of brain development in chimps, Boysen said there's much to glean about brain development in children and the kind of environmental stimulation and communication skills that they need to develop normal attention abilities.

"Our schools likely have many children who have not had the benefit of that kind of socialized attention and directed learning," Boysen said. "And I think once you go past what might be a sensitive period without rich communication with kids, it may be too late. They're going to have challenges for life."