Related Experiment Video
Updated: Jan 11, 2026
11:18
Closed-loop Neuro-robotic Experiments to Test Computational Properties of Neuronal Networks
Published on: March 2, 2015
10.8K
Distributed neural computation and the evolution of the first brains.
Vikram Chandra1,2, Mehrana R Nejad3,4, Allison P Kann1,2
1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge MA 02138.
Biorxiv : the Preprint Server for Biology
|November 19, 2025
Summary
The earliest animal brains may have been diffuse nerve nets. Studies on the Hofstenia miamia worm suggest early brains were unregionalized, with specific brain regions evolving later.
Area of Science:
- Evolutionary biology
- Neuroscience
- Zoology
Background:
- The origin of the brain remains poorly understood, with early forms potentially evolving from Precambrian nerve nets.
- Acoel worms represent a crucial sister lineage for understanding the evolution of brains in animals.
Purpose of the Study:
- To investigate the brain structure and function of *Hofstenia miamia* as a model for early brain evolution.
- To determine if *H. miamia*'s brain exhibits regionalization or functional specialization.
Main Methods:
- High-resolution imaging and neural cell type mapping in *Hofstenia miamia*.
- Behavioral studies, including foraging and hunting, before and after brain tissue removal.
Main Results:
- The *Hofstenia miamia* brain is diffuse with minimal anatomical or functional regionalization.
- Worms can forage successfully even after significant portions of the brain are removed, indicating functional redundancy.
- Increased brain tissue enhances performance, but no single region is essential for hunting.
Conclusions:
- The *Hofstenia miamia* brain may be composed of "computationally pluripotent tiles" that interact to produce behavior.
- This suggests early brains evolved from diffuse nerve nets, with regionalization arising as a secondary development.
Related Concept Videos
01:25Neural Circuits
2.6K
Neural circuits and neuronal pools are two of the main structures found in the nervous system. Neural circuits are networks of neurons that work together to carry out a specific task or process. They consist of interconnected neurons and glial cells, which provide structural and metabolic support.
Neuronal pools are collections of nerve cells with similar functions and interact through chemical and electrical signals. These pools include both interneurons (the central neural circuit nodes that...
Neuronal pools are collections of nerve cells with similar functions and interact through chemical and electrical signals. These pools include both interneurons (the central neural circuit nodes that...
2.6K
01:30Neurulation
45.1K
Neurulation is the embryological process which forms the precursors of the central nervous system and occurs after gastrulation has established the three primary cell layers of the embryo: ectoderm, mesoderm, and endoderm. In humans, the majority of this system is formed via primary neurulation, in which the central portion of the ectoderm—originally appearing as a flat sheet of cells—folds upwards and inwards, sealing off to form a hollow neural tube. As development proceeds, the...
45.1K
01:22Neurons as Communicators of the Brain
2.8K
Neurons, the fundamental units of the brain and nervous system, function as the primary transmitters of information throughout the body. Their ability to communicate through electrical and chemical signals is vital for every bodily function, from regulating the heartbeat to processing complex thoughts. Each neuron has three main components: the cell body (soma), dendrites, and an axon, each specialized to facilitate swift and efficient neural communication.
Cell Body
The cell body, also known...
Cell Body
The cell body, also known...
2.8K
01:28Neuronal Communication
2.9K
Neurons, the fundamental units of the brain and nervous system, communicate through complex electrochemical signals that underpin all cognitive and bodily functions. This communication is primarily facilitated by a process involving the generation and propagation of an action potential along the axon of the neuron. When the internal electrical charge of a neuron surpasses a certain threshold, an action potential is triggered. This rapid change in voltage travels swiftly along the axon to the...
2.9K
01:30Organization of the Brain
2.3K
The brain is an integral component of the nervous system and serves as the center for processing sensory inputs, making decisions, and directing bodily actions. This complex organ is organized into three primary sections: the hindbrain, midbrain, and forebrain, each responsible for a range of vital functions.
Hindbrain
The hindbrain, located at the base of the brain, plays a vital role in regulating automatic processes that sustain life. It includes the medulla oblongata, which is essential for...
Hindbrain
The hindbrain, located at the base of the brain, plays a vital role in regulating automatic processes that sustain life. It includes the medulla oblongata, which is essential for...
2.3K
01:20Introduction to Cognitive Psychology
2.2K
Cognitive psychology is the field of psychology dedicated to examining how people think. It attempts to explain how and why we think the way we do by studying the interactions among human thinking, emotion, creativity, language, and problem-solving, as well as other cognitive processes. Cognitive psychology studies how information is processed and manipulated in remembering, thinking, and knowing.
This field emerged in the mid-20th century, following a period dominated by behaviorism, which...
This field emerged in the mid-20th century, following a period dominated by behaviorism, which...
2.2K