Despite earlier studies showing differences in the prefrontal cortex, later studies suggest that psychopathy is more tightly linked to deficiencies in the limbic and paralimbic areas of the brain. This explains why they are completely rational but morally insane. Hence, if the main aspects of psychopathy stem from these lower regions, they can still use their higher regions to function day to day without raising as many suspicions. For example, when assessing if something is morally right or wrong, psychopaths need to critical think while the rest of us are able to feel it. Therefore, using neurological imaging in addition to the Hare Checklist, a reliable diagnosis of psychopathy can be made.