The modified hole board as a large-scale screen for cognitive alterations
E. Binder, A. Roedel, F. Holsboer and F. Ohl
Max Planck Institute for Psychiatry, Munich, Germany
To understand the influence of a genetic or pharmacological interference on a complex organism, reliable phenotyping methods are of great importance. Therefore, it is necessary to develop dependable behavioral tests that enable us to obtain a differential, and thus a reliable image of the phenotype of an animal.
The modified hole board (mHb) represents a large-scale screening method that allows the reliable investigation and differentiation of a wide variety of behavioral dimensions (e.g. anxiety, arousal, social affinity, exploration and activity) and their interaction in one test. As previous studies have shown, the mHb reveals a realistic and complex overall view of an animal's behavioral phenotype, thus representing a highly useful tool in screening for novel animal models. Since many psychiatric disorders are accompanied by cognitive dysfunctions, it would also be valuable to be able to identify cognitive alterations in the mHb.
Hence, we integrated an object recognition test into the experimental set-up. The object recognition task is mediated primarily by the perirhinal cortex, and it is known that patients suffering from Alzheimer's disease or amnesia are impaired in recognizing objects when compared to controls. To investigate the reliability of the assessment of cognitive performance in the mHb, three mouse strains (C57BL/6, DBA/2 and C3H) were first phenotyped using the mHb test and then tested in a standardized object recognition test in a novel home cage. Next, we tested the same mouse strains in a complex visuo-spatial version of the mHb to evaluate cognitive processes, such as working memory and declarative memory, which differ from those displayed in the object recognition task.
Our results with these three strains of mice showed that the cognitive diversities in recognizing objects observed in the phenotyping screen were reproduced in the selective object recognition test, but that no matching outcomes could be found in the visuo-spatial task. In summary, we show that the mHb could well be used as a reliable large-scale screen for specific cognitive alterations.
Paper presented at Measuring Behavior 2002 , 4th International Conference on Methods and Techniques in Behavioral Research, 27-30 August 2002, Amsterdam, The Netherlands