Lennart Heimer (11 March 1930 – 12 March 2007), was a Swedish-American
neuroscientist and
professor at the Massachusetts Institute of Technology and the University of Virginia. He was most noted for mapping circuits of the brain in the
limbic lobe and
basal ganglia, structures that play central roles in emotion processing and movement.
[ Society for Neuroscience Obituary: Lennart Heimer]
Background
Heimer was born in Östersund,
Sweden. He completed his medical training at the University of Gothenburg. In 1965, Heimer was recruited to join the faculty at the MIT Department of Psychology and Brain Science.
Research
Heimer's first notable achievement was the development of the Fink-Heimer silver stain for mapping the smallest ends of
axons in the brain. With this and other tract-tracing techniques, he made his most well known contribution: a new structural framework for the
striatum. Heimer identified the nucleus accumbens and the olfactory tubercle as striatal structures and termed them the "
ventral striatum."
[Groenewegen HJ, Trimble M. The ventral striatum as an interface between the limbic and motor systems CNS Spectr. 2007 Dec;12(12):887-92.][Stopczynski et al. proliferation in the striatum during postnatal development: preferential distribution in subregions of the ventral striatum Brain Struct Funct. 2008 Sep; 213(0): 119–127.] The traditional striatal structures, the
caudate nucleus and
putamen are, strictly speaking, now termed the 'dorsal' striatum, though in practice the term "
striatum" without qualification generally refers just to the dorsal striatum. Heimer is also known for helping to elaborate the anatomical concept of the extended amygdala, first proposed by his collaborator, Jose de Olmos.
[Elias WJ, Ray DK, Jane JA. Lennart Heimer: concepts of the ventral striatum and extended amygdala. Neurosurg Focus. 2008;25(1):E8.]
