Prof. Onur Gϋntϋrkϋn, Professor of Biological Psychology at the Ruhr University Bochum and 2013 awardee of the highest German research award, the Leibniz Prize, discussed whether neural degrees of freedom exist – i.e. identical mental processes that develop despite different neural wiring.
Mammals, who share very similar brain architectures, are the top predators in every ecosystem. As Prof. Güntürkün noted, they “outsmart the rest.” Influential German neuroanatomist Ludwig Edinger was once convinced that if people understood the evolution of the brain, they would understand the evolution of thought. Edinger’s theory was based on the following evolutionary trajectory: first there were fish, then amphibians, reptiles, birds, and finally mammals, with each species “inventing” and adding new parts to the brain over time.
This developmental trajectory, he attested, accounted for why you could never teach a reptile what you could teach a bird. This notion was widely accepted and persisted as the dominant theory in neuroscience for more than 100 years, but as Prof. Gϋntϋrkϋn and his team have proven, Edinger was ultimately incorrect. In experiments, they have demonstrated that corvids can reach similar levels of cognitive competence as chimps, even though the birds’ brains are much smaller and lighter. Likewise, magpies can obtain the same level of object permanence as human children.
Object permanence is the capacity to understand that objects continue to exist even when they cannot be directly observed. Moreover, magpies not only proceed with the identical stages of cognitive development as human children, but they do so even faster. Magpies are also able to recognize themselves in the mirror. How is it possible that such vastly different brains can produce such similar behavior? Birds have the same neurons as mammals in their neocortex. This means that in terms of brain chemistry, other than by the arrangement of cells, the two species do not markedly differ.Thus, a laminated neocortex, according to Prof. Güntürkün, is not a prerequisite for high cognitive abilities. Whereas Edinger once said, “form before function,” Prof. Gϋntϋrkϋn contradicted, proclaiming, “it’s function before form!”.
Prof. William Hopkins, Professor of Neuroscience and Psychology at Georgia State University, presented on whether apes have a language-ready brain. Humans and chimps not only share a common ancestor from about six million years ago, but they also still have 98 percent of the identical DNA. Modern imaging technology has allowed scientists over the past 20 years to more precisely study how monkeys’ brains work. Research has shown that chimps have the same kinds of cells as humans in the left side of the brain, the region responsible for language abilities.
Even so, chimps are still neurologically wired differently. This might be the reason why apes do not have phonology. In the debate on the origins of language, some argue that in the phase between the existence of chimps’ shared ancestor and today’s modern man, a sign language existed, which was gradually replaced by spoken language. Others reason that evolution directly favored a vocal system for some primates, which ultimately resulted in speech capacities.
In Prof. Hopkins’ opinion, it is most likely a mixture of both theories. Even chimps today use multi-modal means of communication, such as when pointing and screaming at the same time to evoke a specific action from their fellow apes. According to Prof. Hopkins, these attention-seeking sounds most frequently appear to be socially learned. In other words, “if your mom makes these sounds, you make these sounds,” Prof. Hopkins said. Apes are unlikely to communicate only with declarative statements; instead they communicate primarily when needs must be met, such as when requesting food.
Moderator Prof. Dr. Herbert Terrace, Professor of Psychology and Psychiatry at Columbia University, opened the floor to questions from the audience. A lively discussion ensued, with topics ranging from the evolutionary advantages of shrinking the cortex to the relation between social interaction and brain structures.