Herkistymiskäyttäytyminen

Herkistymiskäyttäytyminen, often translated as sensitization behavior, refers to a phenomenon where an organism's response to a particular stimulus increases or becomes more pronounced after repeated exposure to that stimulus. This is in contrast to habituation, where the response decreases with repeated exposure. Sensitization is a form of non-associative learning, meaning it does not involve forming a connection between two different stimuli or between a stimulus and a response. Instead, it modifies the organism's reaction to a single, repeated stimulus.

This heightened responsiveness can manifest in various ways, such as increased motor activity, faster reaction times, or a more intense physiological response like heightened arousal. For example, a creature that is repeatedly startled by a sudden loud noise might become more sensitive to subsequent noises, reacting more strongly even to sounds that are less intense than the initial one. This phenomenon is thought to serve an adaptive purpose, potentially by enhancing an organism's awareness of and readiness to respond to potentially harmful or important stimuli in its environment.

Sensitization has been observed across a wide range of species, from invertebrates like Aplysia sea slugs, where it has been extensively studied in the context of simple neural circuits, to more complex organisms including mammals. The underlying mechanisms often involve changes in neurotransmitter release and receptor sensitivity at the synaptic level, leading to an amplified signal transmission within neural pathways. Understanding sensitization behavior provides insights into the fundamental processes of learning, memory, and neural plasticity.