Thigmotaxis
Thigmotaxis is a behavioral response to tactile stimuli, typically referring to an organism's movement in response to physical contact with surfaces or objects. For example, animals, when placed into a new enclosed space, tend to stay near the perimeter while avoiding the interior area. This is known as wall-following/touching or centrophobic behavior.
This type of movement is genetically grounded and can be observed in both animals and humans.
Types
Positive
This occurs when an organism moves towards or remains in contact with a surface or object. Positive thigmotaxis is often observed in animals seeking shelter or protection, as staying close to surfaces can reduce exposure to predators and environmental hazards.Negative
This occurs when an organism moves away from contact with surfaces or objects. Negative thigmotaxis can be seen in animals that need to navigate open spaces or avoid areas where tactile stimuli indicate danger or discomfort.Examples in animals
Rodents
Laboratory studies of rodents, such as mice and rats, frequently demonstrate positive thigmotaxis. Rodents often prefer to stay close to the walls of an open field or maze, a behavior known as wall-following or thigmotactic behavior. This tendency is utilized in behavioral experiments, such as the open field test, to assess anxiety-like behaviors.Insects
Many insects exhibit thigmotactic behavior. For instance, cockroaches and ants show positive thigmotaxis by staying close to surfaces while foraging or seeking shelter. This behavior helps them navigate complex environments and avoid predation. Similarly to rodents, it is utilized in behavioral experiments, such as the open field test, to assess anxiety-like behaviors.Fish
Certain fish species exhibit thigmotaxis when they seek out and remain close to structures or objects within their aquatic environment. This behavior can provide protection from predators and strong currents.Mechanisms
The mechanisms underlying thigmotaxis involve sensory receptors that detect tactile stimuli. These receptors can be located on various body parts, such as antennae, legs, or skin. When stimulated, these receptors send signals to the nervous system, triggering a motor response that directs the organism's movement.In vertebrates, the mechanoreceptors in the skin, known as tactile or touch receptors, play a significant role in thigmotactic behavior. In invertebrates, specialized sensory organs such as setae or antennae are involved in detecting and responding to tactile stimuli.