Nav: Home

Comparison of primate brains hints at what makes us human

November 23, 2017

A detailed comparative analysis of human, chimpanzee and macaque brains reveals elements that make the human brain unique, including cortical circuits underlying production of the neurotransmitter dopamine. To pinpoint differences among primate brains, André M. M. Sousa et al. evaluated brain tissue samples from six humans, five chimpanzees, and five macaques. They generated transcriptional profiles of 247 tissue samples in total, representing several different brain regions (hippocampus, amygdala, striatum, mediodorsal nucleus of thalamus, cerebellar cortex, and neocortex). The researchers found that 11.9% of messenger RNAs and 13.6% of microRNAs exhibited human-specific up-regulation or down-regulation of genes in at least one brain region. Of particular note, the authors found that human brains exhibited significant up-regulation of two genes that encode enzymes involved in dopamine biosynthesis: tyrosine hydroxylase (TH) and dopa (3,4-dihydroxyphenylalanine) decarboxylase (DDC). Dopamine is known to play a role in aspects of cognition and behavior, such as working memory, reasoning, reflective exploratory behavior, and overall intelligence. This up-regulation of dopamine-related gene expression prompted the researchers to quantify and compare TH+ interneurons in 45 adult brains of nine primate species. The authors confirmed that humans, indeed, have a higher number of TH+ interneurons in both the dorsal caudate nucleus and putamen (striatum) when compared with the nonhuman primates analyzed in this study. The authors discuss possible explanations for the differences in TH+ neurons for these brain regions, for example, differences related to neuron migration and/or differentiation.
-end-


American Association for the Advancement of Science

Related Dopamine Articles:

Brain scans show dopamine levels fall during migraine attacks
Using PET scans of the brain, University of Michigan researchers showed that dopamine falls and fluctuates at different times during a migraine headache.
Hard choices? Ask your brain's dopamine
Salk researchers learn how dopamine governs ongoing decisions, yielding insights into Parkinson's, drug addiction.
Alcoholism may be caused by dynamical dopamine imbalance
Researchers from the Higher School of Economics, Ecole Normale Supérieure, Paris, Indiana University and the Russian Academy of Sciences Nizhny Novgorod Institute of Applied Physics have identified potential alcoholism mechanisms, associated with altered dopaminergic neuron response to complex dynamics of prefrontal cortex neurones affecting dopamine release.
Precise technique tracks dopamine in the brain
MIT researchers have devised a way to measure dopamine in the brain much more precisely than previously possible, which should allow scientists to gain insight into dopamine's roles in learning, memory, and emotion.
Neurotrophic factor GDNF is an important regulator of dopamine neurons in the brain
New research results are expanding our understanding of the physiological role of the glial cell line-derived neurotrophic factor GDNF in the function of the brain's dopamine systems.
More Dopamine News and Dopamine Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#534 Bacteria are Coming for Your OJ
What makes breakfast, breakfast? Well, according to every movie and TV show we've ever seen, a big glass of orange juice is basically required. But our morning grapefruit might be in danger. Why? Citrus greening, a bacteria carried by a bug, has infected 90% of the citrus groves in Florida. It's coming for your OJ. We'll talk with University of Maryland plant virologist Anne Simon about ways to stop the citrus killer, and with science writer and journalist Maryn McKenna about why throwing antibiotics at the problem is probably not the solution. Related links: A Review of the Citrus Greening...