This essay will explore the depths of cognitive neuroscience, focusing on the most common methods of brain scanning with particular reference to non-invasive techniques, while also discussing the ethical considerations on some more invasive methods in cognitive neuroscience. For many years there has been intense debate among neuroscientists when considering ethical considerations in cognitive neuroscience. While it is quite certain that invasive methods are the most effective when localizing functions within the brain, they are also highly unethical and therefore less effective methods must be used for human participants, although on some occasions it is more feasible to use a subject not human. in which case rats are regularly used. It is therefore the responsibility of neuroscientists to identify the most effective method of brain scanning for that particular purpose. Some of the most common non-invasive brain scanning techniques are EEG (electroencephalogram), fMRI (functional magnetic resonance imaging), and PET (positron). Emission topography). This essay will evaluate the effectiveness of these methods by comparing them with invasive methods in order to evaluate which of these methods may be the most appropriate alternative to invasive techniques. To address the ethical considerations involved in cognitive neuroscience, the first method to be developed was the PET scan, introduced in the late 1950s. This is a small amount of radioactive glucose (2-deoxyglucose) to be injected into the carotid artery and accumulated in the most active areas of the body, emitting gamma radiation. These signals are then picked up by computer sensors and transcribed into images of the brain, in this case, it may be more appropriate to use a slower method such as a PET or fMRI could provide a more in-depth description of the activities occurring in the brain. A final consideration in this research is the combination of two methods, such as EEG and fMRI, as both provide undeniable strengths. While EEGs are useful for measuring neuronal activities, fMRIs are useful for localizing specific areas within the brain, and because of this, both methods are able to work together to provide a high-resolution image of the brain while the EEG will allow the researcher to keep a trace of neural activities within the brain. Works Cited http://www.biomedresearches.com/root/pages/researches/epilepsy/eeg_fmri_and_pet.html http://en.wikibooks.org/wiki/Cognitive_Psychology_and_Cognitive_Neuroscience/Behavioural_and_Neuroscience_Methods#EEG