Allgemeine und Biologische Psychologie

Planarians

One of the most fundamental bifurcations in the evolution of the brain is the step from diffuse neural nets such as in jellyfish to a structured "rope-ladder" nervous system with a central and a peripheral part in bilateralians. The latter have for the first time a preferred direction of movement, which comes along with cephalization, the development of a head with an accumulation of sensory organs and ganglia. The cerebral ganglia of early bilateralians might be seen as earliest predecessors of the brain.

One oft he most simple bilateralians are planarians. They are excellent model organisms not only for their remarkable capabilities of regeneration, but also because their nervous system, dopaminergic system and their neurotransmitters are very similar to that of humans. Planarians are probably close relatives to the ancestors of vertebrates, and less related to other invertebrates.

We test the cognition of Schmidtea mediterranea, a freshwater planarian used in regeneration and developmental studies, with a variety of paradigms and setups. In our research, we explore their visual, tactile and spatial memory with t-mazes and test for operant conditioning and simple problem-solving. Furthermore, we look into lateralization and preferences in individuals and the whole population.

 

Schmidtea mediterranea
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Schmidtea MeditteraneaOrganisms Lab down