The Neuwirth Hole-board Test™ is an adaptation of the standard rodent Hole-board test used to assess the cognitive abilities of rodents, such as spatial discrimination, learning, and memory. It combines features from the conventional Hole-board test and the Open Field Arena to assess cognitive abilities, exploratory behaviors, and anxiety-like behaviors in rodents. Neuwirth (2014) and Neuwirth et al. (2017) developed this apparatus to investigate the neuroprotective effects of taurine administration on anxiety-like behaviors learning deficits induced by neurodevelopmental Pb2+ exposure in rodents. 

The Neuwirth Hole-board Test™ consists of a chamber with a perforated floor consisting of sixteen 1″ holes spaced equally apart throughout the apparatus floor. On the first test-day, fear and escape responses (i.e., anxiety-like behaviors) can be examined through the Neuwirth Hole-board Test™ by observing freezing behaviors in the subjects, measuring the latency to make the first head poke in one of the holes of the apparatus, and counting the frequency of head pokes. On the second test day, under each of the four corners of the apparatus, Petri dishes holding contextual odorant cues can be placed. The odorants should be of four different cues, which are used to encourage exploration in the subjects and also be used to observe the effect of different odors on exploratory behaviors in rodents.  The same dependent measures are recorded on test day two and the change in these dependent measures from test day one indicates an inhibitory shift from the behavioral avoidance systems to the behavioral approach systems in rodents. Moreover, the Neuwirth Hole-board™ can also be used to observe the effect of different pharmacological manipulations, brain lesions, and rodent models of diseases and disorders that have behavioral phenotypes for GABAergic-dependent behaviors, anxiety-like behaviors, and exploratory behaviors in rodents. Moreover, since the Neuwirth Hole-board Test™ is an adaptation of the conventional Hole-board test, it can also assess several unconditioned behaviors like the conventional Hole-board test apparatus, such as locomotor activity, habituation, risk assessment, social affinity, and arousal in rodents. 

Other hole-board tests or hole-board test adaptations to study rodent behavior and other animals’ behavior include the Automated Hole-board, the Olfactory Hole-board, and the Pig Hole-board. 

Clean the apparatus after every test to prevent odor cues from previous tests that would otherwise confound subsequent rodent task performance. Appropriately illuminate the apparatus at 300 Lux. Use a behavioral tracking and recording system such as the Behavior Cloud can be used to assist with observations.

The Neuwirth Hole-board Test™  is adapted to improve the protocols of the conventional rodent Hole-board test.  Day one is dedicated to testing anxiety-associated behaviors while the subject encounters a novel environment, while day two tests for exploratory behaviors to the odor cues. The subject is familiarized with the environment on day two which allows for a more accurate analysis of exploratory behaviors as a functional test of the rodent’s GABAergic system and its expression in their ability to exhibit an inhibitory shift through their behaviors.

Neuwirth Hole-board Test™  

The Neuwirth Hole-board Test™ consists of testing the subjects on the apparatus on two consecutive days using the following protocol:

• Day 1 – place the subject in the Neuwirth Hole-board Test™ and allow it to explore the apparatus for 10 minutes.
• Day 2 – place four different olfactory gradients on separate Petri dishes below the four corners of the apparatus. Place the subject in the apparatus and allow it to explore it for 10 minutes. The olfactory gradients are used to encourage exploratory behaviors.

Investigation of the effect of Taurine administration on learning deficits induced by developmental Pb2+ (lead) exposure in rats 

Neuwirth et al. (2017) investigated the effect of taurine administration on learning deficits induced by developmental lead exposure in Long-Evan rats using the Neuwirth Hole board. Before testing, control rat pups were fed a regular diet while the lead-exposed rats were fed a diet containing 1.5g/kg lead acetate. Twenty-two subjects were randomly assigned to four treatment groups: Control, Control + Taurine, Lead, and Lead +Taurine. Testing on the Neuwirth Holeboard was performed on two consecutive days when the subjects were at postnatal day 30-40. The Taurine groups were administered with 43 mg/kg i.p. injection of Taurine 15 minutes before testing. On the first day, the subjects were allowed to explore the apparatus for 10 minutes to assess their anxiety behaviors. Testing on the second day was performed in the same manner as the first day; however, four Petri dishes, each having a novel olfactory gradient (vanilla, lemon, orange, and almond) were placed below the four corners of the Neuwirth Holeboard apparatus to encourage exploratory behaviors. The results from day 1 indicated that lead exposure increased freezing behaviors. On day 2, lead exposure reduced exploration behaviors as compared to controls. Moreover, Taurine administration showed little effects on control on both testing days; however, taurine administration in the lead-exposed subjects reduced freezing and increased exploration behaviors at similar levels to controls.

• The Neuwirth Hole-board Test™  is an adaptation of the conventional rodent Hole-board test and is designed to improve the study of anxiety-like behaviors vs. exploratory-versus in rodents.
• The Neuwirth Hole-board Test™  is used to assess anxiety-like behaviors and exploratory behaviors in rodents.
• It is an adaptation of the conventional rodent Hole-board test. Therefore, it can be used to examine several other unconditioned rodent behaviors as well, such as spatial working memory and spatial learning. 
• It consists of a chamber with a perforated floor containing sixteen 1″ holes spaced equally apart. Under each hole, contextual cues or food rewards can be placed.
• The Neuwirth Hole-board Test™  can test the effect of different drugs or diseases and disorders on anxiety-like behaviors and exploratory behaviors of rodents. 

1. Neuwirth, L. S., Volpe, N. P., Corwin, C., Ng, S., Madan, N., Ferraro, A. M., Furman, Y., & El Idrissi, A. (2017). Taurine Recovery of Learning Deficits Induced by Developmental Pb2+ Exposure. Advances in experimental medicine and biology, 975 Pt 1, 39–55. https://doi.org/10.1007/978-94-024-1079-2_4