The determination of cognitive deficits as well as the use of advanced neuroimaging technique in epileptic patients is important especially in IGE because it reveals the possibility of seizures arise from focal brain pathology in what appear otherwise as generalized epilepsy syndromes.Methods: Thirty IGE patients (10 with JME, 10 with GTC and 10 with CAE), and 10 healthy matched controls were submitted to a neuropsychological evaluation using a battery of psychometric tests for assessment of global intellectual functions, attention, memory, mental speed and information processing and to a single voxel MRS of Rt thalamus and prefrontal cortex measuring N-acetylaspartate (NAA) and NAA/creatine (Cr).Results: Patients with IGE were found to perform worse than controls in all administered tasks with a significant correlation between the poor performance of the patients and the duration of the epilepsy or seizure frequency. A significant reduction of Rt thalamic and prefrontal cortex NAA and NAA/Cr ratio was observed in patients with IGE with a significant correlation between the change in neurometabolites of the patients and the seizure frequency. JME patients show significant reduction of NAA/Cr ratio in prefrontal cortex in comparison to other patients groups.Discussion: This study shows evidence of impaired cognitive functions, in addition to neuronal dysfunction in the Rt thalamus and prefrontal cortex of patients with IGE, supporting the notion of abnormal thalamo-cortical circuitry as a substrate of seizure generation in this form of epilepsy. JME patients can show some frontal dysfunction, which may affect both epileptogenic features and cognitive processes.