New replicable anxiety-related measures of wall vs. center behavior of mice in the open field

Anxiety is a widely studied psychiatric disorder and is thought to be a complex and multidimensional phenomenon. Sensitive behavioral discrimination of animal models of anxiety is crucial for the elucidation of the behavioral components of anxiety and the physiological processes that mediate them. Commonly used behavior paradigms of anxiety usually include only a few automatically collected measures; these do not exhaust the behavioral richness exhibited by animals, thus perhaps missing important differences between preparations. The aim of the present study was to expand the repertoire of automatically collected measures in a classical test of anxiety: behavior in relation to the wall in the open field. We present an algorithm, based on the Software for the Exploration of Exploration strategy, which automatically partitions the mouse path into intrinsically defined patterns of movement near the wall and in the center. These patterns are used to design new end points, which provide an articulated description of various aspects of behavior near the wall and in the center. Sixteen new end points were designed with data from C57BL/6J and DBA/2J mice tested in three laboratories. The strain differences in all end points were evaluated on another data set to assess their validity and were found to remain stable. Ten of the sixteen end points were found to discriminate between the two strains in a replicable manner. The entire set of end points can be used on various genetic and pharmacological models of anxiety with good prospects of providing fine discrimination in a replicable manner.

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Effect of Estrous Cycle on Behavior of Females in Rodent Tests of Anxiety

Frontiers in Psychiatry ◽

10.3389/fpsyt.2021.711065 ◽

2021 ◽

Vol 12 ◽

Author(s):

Thelma A. Lovick ◽

Hélio Zangrossi

Keyword(s):

Menstrual Cycle ◽

Animal Models ◽

Estrous Cycle ◽

Conditioned Fear ◽

Strain Differences ◽

Basic Research ◽

Cycle Phase ◽

Behavioral Tests ◽

Animal Models Of Anxiety ◽

Fear And Anxiety

Anxiety disorders are more prevalent in women than in men. In women the menstrual cycle introduces another variable; indeed, some conditions e.g., premenstrual syndrome, are menstrual cycle specific. Animal models of fear and anxiety, which form the basis for research into drug treatments, have been developed almost exclusively, using males. There remains a paucity of work using females and the available literature presents a confusing picture. One confound is the estrous cycle in females, which some authors consider, but many do not. Importantly, there are no accepted standardized criteria for defining cycle phase, which is important given the rapidly changing hormonal profile during the 4-day cycle of rodents. Moreover, since many behavioral tests that involve a learning component or that consider extinction of a previously acquired association require several days to complete; the outcome may depend on the phase of the cycle on the days of training as well as on test days. In this article we consider responsiveness of females compared to males in a number of commonly used behavioral tests of anxiety and fear that were developed in male rodents. We conclude that females perform in a qualitatively similar manner to males in most tests although there may be sex and strain differences in sensitivity. Tests based on unconditioned threatening stimuli are significantly influenced by estrous cycle phase with animals displaying increased responsiveness in the late diestrus phase of the cycle (similar to the premenstrual phase in women). Tests that utilize conditioned fear paradigms, which involve a learning component appear to be less impacted by the estrous cycle although sex and cycle-related differences in responding can still be detected. Ethologically-relevant tests appear to have more translational value in females. However, even when sex differences in behavior are not detected, the same outward behavioral response may be mediated by different brain mechanisms. In order to progress basic research in the field of female psychiatry and psychopharmacology, there is a pressing need to validate and standardize experimental protocols for using female animal models of anxiety-related states.

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Phenomenology and Epidemiology of Trichotillomania

10.1093/oxfordhb/9780195389715.013.0039 ◽

2012 ◽

Author(s):

Samuel R. Chamberlain

Keyword(s):

Animal Models ◽

Psychiatric Disorder ◽

Hair Loss ◽

Functional Impairment ◽

Repetitive Behaviors ◽

Hair Pulling ◽

Affect Dysregulation ◽

Obsessive Compulsive

Trichotillomania is a psychiatric disorder characterized by recurrent hair pulling, leading to hair loss and functional impairment. This chapter reviews the phenomenology and epidemiology of trichotillomania, and considers its relationship with putative obsessive-compulsive spectrum conditions and other body-focused repetitive behaviors. Salient animal models of the disorder, along with findings in human patients using neuroimaging and cognitive probes, are summarized. A brain-based model of trichotillomania is formulated, focusing on affect dysregulation, addiction, and impulse dyscontrol. Finally, the chapter flags cardinal questions for the attention of future clinical and research scrutiny.

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