Habituation mechanisms and their importance for cognitive function

Sensory processing in autism spectrum disorders and Fragile X syndrome—From the clinic to animal models

“…Humans or animals with normal PPI display strongly attenuated startle responses (by up to 70–90%) to the loud acoustic stimulus if it is preceded by the quieter pre-pulse stimulus, whereas individuals with diminished sensorimotor gating display less attenuation of startle responses by the pre-pulse (Braff et al, 1992; Swerdlow et al, 1994). The neural circuitry mediating acoustic startle responses is well-described and seems to be highly conserved (Schmid et al, 2014; Swerdlow et al, 1999). Secondary auditory neurons in the cochlear nucleus (cochlear root in mice and rats) innervate giant neurons in the caudal pontine reticular formation that directly activate cranial and spinal motorneurons (Koch, 1999; Nodal and Lopez, 2003; Swerdlow et al, 1999).…”

“…Sensitization describes the opposite, an increment in response to the same stimulus over time. Habituation and sensitization are thought to be independent processes, modulating the same behavioural response in opposite ways (Groves and Thompson, 1970; Rankin et al, 2009; Schmid et al, 2014). An overall sensitization is often found in the first 2–4 trials of a block of startle-eliciting stimuli, followed by a gradual decline in responses (habituation) to the remainder of presented trials (Aggernaes et al, 2010; Meincke et al, 2004).…”

Habituation Is More Than Learning to Ignore: Multiple Mechanisms Serve to Facilitate Shifts in Behavioral Strategy

“…Animals need to be able to learn, to change their behavior as a result of experience, in order to thrive in constantly changing environments. Habituation, often described as “the simplest form of learning” and a “cognitive building block” required for more complex forms of learning and memory, has served as an important model phenomenon to investigate the neural mechanisms underlying learning . Habituation is a nonassociative form of learning classically defined as a response decrement that results from repeated stimulation and that cannot be explained by sensory adaptation or motor fatigue (Table ) .…”

“…This clear behavioral conservation led to a hypothesis of a conserved mechanism of habituation that spurred scientists to use a multitude of different organisms, behaviors, and experimental approaches to study habituation. This research has not supported the hypothesis of a single mechanism of habituation, but instead has uncovered numerous components of the pre‐ and postsynaptic mechanisms involved (see Box ) . To date, delineated aspects of the molecular mechanisms of habituation ultimately culminate in either decrease in intrinsic neural excitability, homosynaptic depression of excitatory neurotransmission, or network‐level potentiation of inhibitory neurotransmission (see Box ) .…”

Rapid plasticity attenuation soon after birth revealed by habituation in newborn chicks

“…| 445 reported here concerns a ubiquitous phenomenon among human and non-human animals (i.e., habituation), and that regards different types of physiological (Barry, 2009) and motor responses (Rankin & Carew, 1987), as well as cognitive functions (Schmid, Wilson, & Rankin, 2015;Turatto & Pascucci, 2016;Turatto et al, 2017). On the contrary, the form of plasticity FIGURE 3 Habituation, dishabituation, and sensitization as a function of maturation in Gallus gallus, Rattus norvegicus, and Aplysia californica.…”