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The assessment of memory functions related to medial temporal lobe has become one of the most important issues on current neuropsychology. On this communication, we review the results which our research group has achieved using two functional magnetic resonance Image procedures to assess memory function: Hometown walking task and an encoding/retrieval task using complex images. Nine patients with tumoural temporal lesions performed the hometown walking task. The results of these patients showed either a bilateral or contralesional representation of memory function. These results confirm those obtained by Jokeit, Okujava y Woermann (2001), and they seem to prove that this protocol is useful to determine the preservation of memory function in the non damaged hemisphere. On the other hand, the images encoding/retrieval task has been run by two groups of four patients diagnosed as Alzheimer disease and mild cognitive impairment, and another group of five patients who participated as a control group. According to our hypothesis, the results have shown a lower activation at the left parahippocampal gyrus in mild cognitive impairment and Alzheimer disease patients than controls, just as a lower bilateral activation in the same structure for the Alzheimer group than the control group. As a whole, our results show how important may become functional magnetic resonance image for neuropsychological assessment of memory, and as a diagnostic tool for CNS diseases.

Aims: This paper reviews and describes cases involving useful protocols for pre-surgical evaluation in functional magnetic resonance imaging (fMRI) of the motor, mnemonic and linguistic functions., Development: The application of fMRI in pre-surgical evaluation allows us to pinpoint the anatomical location of a function in relation to the lesion. This technique therefore appears as an alternative to the classical intraoperative tests, which are more aggressive and costly. The paper describes aspects and considerations of fMRI with regard to the methodology and procedure employed in its application, as well as the control of contaminating variables that can affect results. The language protocols are described in terms of lateralisation and localisation, and are divided into expressive and receptive language protocols, together with linguistic protocols for overall stimulation that allow the localisation of both expressive and receptive areas. Concerning the motor protocols, we describe the procedures for patients with and without difficulties in their movement. Lastly, we review and describe the memory protocols that give rise to bilateral stimulation in the mesial temporal areas, which allows both lateralisation and localisation of the hippocampal and parahippocampal areas that are functionally significant for the patients' memory. Each of the protocols is illustrated with cases carried out by our work team., Conclusions: The development of new protocols for pre-surgical evaluation must be guided by greater delimitation and consistency in functional stimulation, as well as analysis of the behaviour displayed.