Dopamine modulates visual threat processing in the superior colliculus via D2 receptors

AbstractDopamine (DA) system is intriguing in the aspect that distinct, typically opposing physiological functions are mediated by D1 dopamine receptors (Drd1) and D2 dopamine receptors (Drd2). Both Drd1+ and Drd2+ neurons were identified in superior colliculus (SC), a visuomotor integration center known for its role in defensive behaviors to visual threats. We hypothesized that Drd1+ and Drd2+ neurons in the SC may play a role in promoting instinctive defensive responses.Optogenetic activation of Drd2+ neurons, but not Drd1+ neurons, in the SC triggered strong defensive behaviors. Chemogenetic inhibition of SC Drd2+ neurons decreased looming-induced defensive behavior, suggesting involvement of SC Drd2+ neurons in defensive responses. To further confirm this functional role of Drd2 receptors, pretreatment with the Drd2+ agonist quinpirole in the SC impaired looming-evoked defensive responses, suggesting an essential role of Drd2 receptors in the regulation of innate defensive behavior. Inputs and outputs of SC Drd2+ neurons were investigated using viral tracing: SC Drd2+ neurons mainly receive moderate inputs from the Locus Coeruleus (LC), whilst we did not find any incoming projections from other dopaminergic structures. Our results suggest a sophisticated regulatory role of DA and its receptor system in innate defensive behavior.

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A role for cerebral cortex in the suppression of innate defensive behavior

10.1101/2020.12.22.424023 ◽

2020 ◽

Author(s):

Silvia Natale ◽

Maria Esteban Masferrer ◽

Senthilkumar Deivasigamani ◽

Cornelius T. Gross

Keyword(s):

Cerebral Cortex ◽

Defensive Behavior ◽

Surgical Removal ◽

Aversive Stimuli ◽

Defensive Responses ◽

Defensive Behaviors ◽

Cortical Regions ◽

Neuron Function ◽

Stressful Stimulus

AbstractThe cerebral cortex is involved in the control of cognition and the processing of learned information and it appears to have a role in the adaptation of behavior in response to unpredictable circumstances. In addition, the cortex may have a role in the regulation of innate responses since rodents, cats or primates with surgical removal or accidental destruction of cortical regions show excessive irritability, aggression and rage elicited by threatening stimuli. However, it remains unclear whether cortex has an acute role in suppressing innate threat responses because the imprecision and chronic nature of these lesions leaves open the possibility that compensatory processes may underlie some of these phenotypes. In the present study we used pharmacogenetic inhibition to precisely, rapidly and reversibly suppress cortical pyramidal neuron function and examine its contribution to defensive behaviors elicited by a variety of innately aversive stimuli. Inhibition of cortex caused an increase of defensive responses elicited by an aggressive conspecific, a novel prey, and a physically stressful stimulus. These findings are consistent with a role of cortex in the acute inhibition of innate defensive behaviors.

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Pharmacological evidence for a role of D2 dopamine receptors in the defensive behavior of the mouse

Behavioral and Neural Biology ◽

10.1016/s0163-1047(88)90804-7 ◽

1988 ◽

Vol 50 (1) ◽

pp. 98-111 ◽

Cited By ~ 34

Author(s):

Stefano Puglisi-Allegra ◽

Simona Cabib

Keyword(s):

Dopamine Receptors ◽

Defensive Behavior ◽

D2 Dopamine Receptors

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Sequential arousal and airway-defensive behavior of infants in asphyxial sleep environments

Journal of Applied Physiology ◽

10.1152/jappl.1997.83.1.219 ◽

1997 ◽

Vol 83 (1) ◽

pp. 219-228 ◽

Cited By ~ 83

Author(s):

Anna S. Lijowska ◽

Nevada W. Reed ◽

Barbara A. Mertins Chiodini ◽

Bradley T. Thach

Keyword(s):

Defensive Behavior ◽

Complete Sequence ◽

Bedding Material ◽

Limb Movements ◽

Defensive Responses ◽

Defensive Behaviors ◽

Stereotyped Behaviors ◽

Motor Activities ◽

Eyes Open ◽

Multiple Measurements

Lijowska, Anna S., Nevada W. Reed, Barbara A. Mertins Chiodini, and Bradley T. Thach. Sequential arousal and airway-defensive behavior of infants in asphyxial sleep environments. J. Appl. Physiol. 83(1): 219–228, 1997.—Infants are prone to accidental asphyxiation. Therefore, we studied airway-defensive behaviors and their relationship to spontaneous arousal behavior in 41 healthy sleeping infants (2–26 wk old), using two protocols: 1) infant was rebreathing expired air, face covered by bedding material; and 2) infant was exposed to hypercarbia, face uncovered. Multiple measurements of respiratory and motor activities were recorded (video, polygraph). The infants’ response to increasing hypercarbia consisted of four highly stereotyped behaviors: sighs (augmented breaths), startles, thrashing limb movements, and full arousal (eyes open, cry). These behaviors occurred abruptly in self-limited clusters of activity and always in the same sequence: first a sigh coupled with a startle, then thrashing, then full arousal. Incomplete sequences (initial behaviors only) occurred far more frequently than the complete sequence and were variably effective in removing the bedding covering the airway. In both protocols, as inspired CO2increased, incomplete arousal sequences recurred periodically and with increasing frequency and complexity until the infant either succeeded in clearing his/her airway or was completely aroused. Spontaneous arousal sequences, identical to those occurring during hypercarbia, occurred periodically during sleep. This observation suggests that the infant’s airway-defensive responses to hypercarbia consist of an increase in the frequency and complexity of an endogenously regulated, periodically occurring sequence of arousal behaviors.

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