Electrical stimulation of midbrain tectum structures, particularly the dorsal periaqueductal gray (dPAG) and inferior colliculus (IC), produces defensive responses, such as freezing and escape behavior. Freezing also ensues after termination of dPAG stimulation (post-stimulation freezing). These defensive reaction responses are critically mediated by γ-aminobutyric acid and 5-hydroxytryptamine ...

objective: biomaterial technology, when combined with emerging human induced pluripotent stem cell (hipsc) technology, provides a promising strategy for patient-specific tissue engineering. in this study, we have evaluated the physical effects of collagen scaffolds fabricated at various freezing temperatures on the behavior of hipsc-derived neural progenitors (hipsc-nps). in addition, the coati...

We studied the effects of perospirone (SM-9018), a novel serotonin-2 (5-HT2) and dopamine-2 (D2) receptor antagonist (SDA), on conditioned fear stress (CFS)-induced freezing behavior in rats and compared its actions with those of other antipsychotics. Exposure of rats to the environment previously paired with foot shock induced marked freezing behavior, which was reduced by the anxiolytic diaze...

2,4,5 dihydro 2,5 trimethylthiazoline (TMT) is a synthesized component of red fox anal secretions that reliably elicits defensive behaviors in rats and mice. TMT differs from other predator odors because it is a single molecule, it can be synthesized in large quantities, and the dose for exposure is highly controllable in an experimental setting. TMT has become a popular tool for studying the b...

Freezing of gait (FOG) is a common, disabling gait disturbance in Parkinson's disease (PD) and other Parkinsonian syndromes. Freezing also occurs during non-gait movements involving the upper limbs. The mechanisms underlying freezing are complex, likely involving motor, cognitive, and sensory systems that contribute to the episodes. Here, we reported a 60-year-old female with a 24-year history ...

Animals present an enormous variety of behavioral defensive mechanisms, which increase their survival, but often at a cost. Several animal taxa reduce their chances of being detected and/or recognized as prey items by freezing (remaining completely motionless) in the presence of a predator. We studied costs and benefits of freezing in immature Eumesosoma roeweri (Opiliones, Sclerosomatidae). Pr...

ackground: A key to successful adaptation is the ability to regulate emotional responses in relation to changing environmental emands or contexts. ethods: High-resolution PET fluoro-deoxyglucose (FDG) scanning in rhesus monkeys was performed during two contexts (alone, nd human intruder with no eye contact) during which the duration of anxiety related freezing behavior was assessed. Correlation...