We have studied the magnetic and magnetotransport properties of Pr0.50Ca0.50CoO3 (prepared using high pressure routes). We find that below the metal-insulator and spin state transition (MIT), the system can be described as a paramagnetic insulator. In this regime, it presents a considerable negative magnetoresistance (20%-40%), while above MIT the magnetoresistance is negligible or even slightly positive. These results seem in contradiction with the spin state picture usually drawn for this system.