ABSTRACT: Animal models are essential to investigate the mechanisms responsible for the cognitive and motor alterations in minimal or clinical hepatic encephalopathy (HE). The characterization of these mechanisms allows identifying new therapeutic targets which modulation may improve neurological function in patients. Animal models also allow testing if treatments directed to modulate these targets improve cognitive and motor function. These studies require evaluation of cognitive and motor function in animal models. It is important to understand which tests can be performed in rodents, which cognitive and motor aspects are evaluated by the tests and how they can be related to cognitive and motor dysfunction in the patients. The earliest alterations in patients with minimal HE (MHE) include attention deficits, psychomotor slowing, impairment of visuo-motor and bimanual coordination, of working memory, spatial memory, long-term memory, spatial orientation, verbal learning, concentration, balance and equilibrium, associated with increased falls. To understand the mechanisms involved in each type of cognitive and motor alteration in MHE the behavioral tests in animal models should be designed to evaluate these neurological alterations by procedures that maximize the translatability to the human situation and the utility to evaluate treatments to improve cognitive and motor impairment. Many functions are evaluated in humans using pencil or computerized tests such as number connection tests, repetition of series of words or numbers, naming colors, and other actions which can't be reproduced exactly in animal models. Functions such as verbal learning can't be evaluated in animal models. However, a good number of cognitive and motor processes impaired in patients with MHE may be evaluated in rodents using appropriate behavioral tests. For example, a combination of properly designed tests in the radial maze, Morris water maze, object recognition and object location allows evaluating with high sensitivity working memory, reference memory and distinguishing the spatial and non-spatial components of working and reference memory. These components are altered in rats with MHE and different mechanisms are involved in the impairment of different components. Also, there are pharmacological treatments that restore selectively working or reference memory and spatial or non-spatial learning and memory in rats with MHE. There are also appropriate test to assess some motor alterations: hypokinesia, fine motor coordination or balance. Studies based on proper use of animal models will accelerate the advance in understanding the mechanisms involved in MHE and will open new therapeutic approaches to improve quality of life and life span of the patients.