Under or Absent Reporting of Light Stimuli in Testing of Anxiety-Like Behaviors in Rodents: The Need for Standardization

Abstract

Behavioral neuroscience tests such as the Light/Dark Test, the Open Field Test, the Elevated Plus Maze Test, and the Three Chamber Social Interaction Test have become both essential and widely used behavioral tests for transgenic and pre-clinical models for drug screening and testing. However, as fast as the field has evolved and the contemporaneous involvement of technology, little assessment of the literature has been done to ensure that these behavioral neuroscience tests that are crucial to pre-clinical testing have well-controlled ethological motivation by the use of lighting (i.e., Lux). In the present review paper, N = 420 manuscripts were examined from 2015 to 2019 as a sample set (i.e., n = ~20–22 publications per year) and it was found that only a meager n = 50 publications (i.e., 11.9% of the publications sampled) met the criteria for proper anxiogenic and anxiolytic Lux reported. These findings illustrate a serious concern that behavioral neuroscience papers are not being vetted properly at the journal review level and are being released into the literature and public domain making it difficult to assess the quality of the science being reported. This creates a real need for standardizing the use of Lux in all publications on behavioral neuroscience techniques within the field to ensure that contributions are meaningful, avoid unnecessary duplication, and ultimately would serve to create a more efficient process within the pre-clinical screening/testing for drugs that serve as anxiolytic compounds that would prove more useful than what prior decades of work have produced. It is suggested that improving the standardization of the use and reporting of Lux in behavioral neuroscience tests and the standardization of peer-review processes overseeing the proper documentation of these methodological approaches in manuscripts could serve to advance pre-clinical testing for effective anxiolytic drugs. This report serves to highlight this concern and proposes strategies to proactively remedy them as the field moves forward for decades to come.

Involvement of the GABAergic system in PTSD and its therapeutic significance

“…It is important to note that when testing different strains of mice, it would be essential to validate the testing or scoring procedure ( Valentinuzzi et al, 1998 ). To avoid artificially inflated lighting sources and thus ensure freezing behavior is induced in a well-controlled manner, it is suggested to report Lux and control the lighting properly ( Neuwirth et al, 2022 ). When a neutral cue or context [a sound, light, or conditioned stimulus (CS)] occurs with a highly aversive signal or unconditioned stimuli (US) and leads to fear behaviors or conditioned fear responses (CRs), which include freezing, a systemic response to behavior besides breathing, fear acquisition arises [47].…”

Effects of glycogen synthase kinase-3β activity inhibition on cognitive, behavioral, and hippocampal ultrastructural deficits in adulthood associated with adolescent methamphetamine exposure

“…In all behavioral tests, a white LED light with diffuser plate was suspended 2.5 meters above the center of the apparatus, and the illumination of the apparatus floor was approximately 50 Lux. Previous study reported this illumination may have neither anxiogenic stimulus nor anxiolytic stimulus ( Neuwirth et al, 2022 ).…”

Multidimensional behavioral profiles associated with resilience and susceptibility after inescapable stress

“…It is important to emphasize that other factors were controlled during the experimental battery, such as lighting that can provoke behavioral alterations 81 . The light intensity was adjusted in different protocols to minimize light as an aversive factor and avoid compromising performance, which could lead to anxiogenic behaviors described in the literature 82 , based on previously published protocols.…”