Show/hide main menu


News Highlights

'Strikingly similar' brains of man and fly may aid mental health research

Posted on 11/04/2013
Brain of an adult fruitfly - Dr Frank Hirth, King's College London

Brain of an adult fruitfly (magenta) and central complex (green) - Image credit: Dr Frank Hirth, King's College London

A new study by scientists at King's College London's Institute of Psychiatry and the University of Arizona (UA) published in Science reveals the deep similarities in how the brain regulates behaviour in arthropods (such as flies and crabs) and vertebrates (such as fish, mice and humans). 

The findings shed new light on the evolution of the brain and behaviour and may aid understanding of disease mechanisms underlying mental health problems.

Based on their own findings and available literature, Dr Frank Hirth (King's) and Dr Nicholas Strausfeld (UA) compared the development and function of the central brain regions in arthropods (the 'central complex') and vertebrates (the 'basal ganglia').

Research suggests that both brain structures derive from embryonic stem cells at the base of the developing forebrain and that, despite the major differences between species, their respective constitutions and specifications derive from similar genetic programmes.

The authors describe that nerve cells in the central complex and the basal ganglia become inter-connected and communicate with each other in similar ways, facilitating the regulation of adaptive behaviours. In other words, the response of a fly or a mouse to internal stimuli such as hunger or sleep, and external stimuli such as light/dark or temperature, are regulated by similar neural mechanisms.

Dr Hirth from the Department of Neuroscience at King's Institute of Psychiatry says: "Flies, crabs, mice, humans: all experience hunger, need sleep and have a preference for a comfortable temperature so we speculated there must be a similar mechanism regulating these behaviours. We were amazed to find just how deep the similarities go, despite the differences in size and appearance of these species and their brains."

Dr Strausfeld, a Regents Professor in the UA's Department of Neuroscience and the Director of the UA's Center for Insect Science, says: "When you compare the two structures, you find that they are very similar in terms of how they're organized. Their development is orchestrated by a whole suite of genes that are homologous between flies and mice, and the behavioral deficits resulting from disturbances in the two systems are remarkably similar as well."

In humans, dysfunction of the basal ganglia can cause severe mental health problems ranging from autism, schizophrenia and psychosis, to neurodegeneration - as seen in Parkinson's disease, motor neurone disease and dementia - as well as sleep disturbances, attention deficits and memory impairment. Similarly, when parts of the central complex are affected in fruit flies, they display similar impairments.

Dr Hirth (King's) adds: "The deep similarities we see between how our brains and those of insects regulate behaviour suggest a common evolutionary origin. It means that prototype brain circuits, essential for behavioural choice, originated very early and have been maintained across animal species throughout evolutionary time. As surprising as it may seem, from insects' dysfunctional brains, we can learn a great deal about how human brain disorders come about."

The findings suggest that arthropod and vertebrate brain circuitries derive from a common ancestor already possessing a complex neural structure mediating the selection and maintenance of behavioural actions.

Although no fossil remains of the common ancestor exist, trace fossils, in the form of tracks criss-crossing the seafloor hundreds of millions of years ago, reveal purposeful changes in direction.

Dr Strausfeld (UA) says: "If you compare these tracks to the tracks left behind by a foraging fly larva on an agar plate or the tunnels made by a leaf-mining insect, they’re very similar. They all suggest that the animal chose to perform various different actions, and action selection is precisely what the central complex and the basal ganglia do."

The trace fossils may thus support the early existence of brains complex enough to allow for action selection and a shared ancestry of neural structures between invertebrates and vertebrates.

The study was funded by the UK Medical Research Council (MRC), the Royal Society, Parkinson's UK, Motor Neurone Disease Association, Alzheimer's Research UK, Foundation Thierry Latran (to F.H.), and the Air Force Research Laboratories and the Centre for Insect Science at the University of Arizona (to N.J.S.).

Paper reference: Strausfeld, N.J. and Hirth, F. 'Deep homology of arthropod central complex and vertebrate basal ganglia', Science 340, 157-161 d.o.i:10.1126/science.1231828

For further information, please contact Seil Collins, Press Officer, King's College London, Institute of Psychiatry. Tel: (+44) 0207 848 5377 email:

For further information about King’s visit our 'King’s in Brief' page

News Highlights:

News Highlights...RSS FeedAtom Feed

£1.3m grant for epilepsy self-management trial

£1.3m grant for epilepsy self-management trial

Researchers at King's Institute of Psychiatry have been awarded £1.3m by the NIHR to assess the effectiveness of self-management education for adults with poorly-controlled epilepsy.
Epigenetic changes shed light on biological mechanism of autism

Epigenetic changes shed light on biological mechanism of autism

Scientists from King's Institute of Psychiatry have identified patterns of epigenetic changes involved in autism, shedding light on the biological mechanism by which environmental influences regulate the activity of certain genes involved in the development of autism.
IoP at Wonder Season: art & science of the brain

IoP at Wonder Season: art & science of the brain

Staff and students from the Institute of Psychiatry at King's took part in a wide range of events for the Wellcome Trust Wonder Season at the Barbican, inspiring children and adults alike about the world of neuroscience.
Sitemap Site help Terms and conditions  Privacy policy  Accessibility  Modern slavery statement  Contact us

© 2020 King's College London | Strand | London WC2R 2LS | England | United Kingdom | Tel +44 (0)20 7836 5454