Traditional neuroscience has for many years considered the nervous system as an isolated entity and largely ignored influences of the social environments in which humans and many animal species live. In fact, we now recognize the considerable impact of social structures on the operations of the brain and body. These social factors operate on the individual through a continuous interplay of neural, neuroendocrine, metabolic and immune factors on brain and body, in which the brain is the central regulatory organ and also a malleable target of these factors. Social neuroscience investigates the biological mechanisms that underlie social processes and behavior, widely considered one of the major problem areas for the neurosciences in the 21st century, and applies concepts and methods of biology to develop theories of social processes and behavior in the social and behavioral sciences. Social neuroscience capitalizes on biological concepts and methods to inform and refine theories of social behavior, and it uses social and behavioral constructs and data to advance theories of neural organization and function.
Throughout most of the 20th century, social and biological explanations were widely viewed as incompatible. But advances in recent years have led to the development of a new approach synthesized from the social and biological sciences. The new field of social neuroscience emphasizes the complementary relationship between the different levels of organization, spanning the social and biological domains (e.g., molecular, cellular, system, person, relational, collective, societal) and the use of multi-level analyses to foster understanding of the mechanisms underlying the human mind and behavior.
A number of methods are used in social neuroscience to investigate the confluence of neural and social processes. These methods draw from behavioral techniques developed in social psychology, cognitive psychology, and neuropsychology, and are associated with a variety of neurobiological techniques including functional magnetic resonance imaging (fMRI), magnetoencephalography (MEG), positron emission tomography (PET), facial electromyography (EMG), transcranial magnetic stimulation (TMS), electroencephalography (EEG), event-related potentials (ERPs), electrocardiograms, electromyograms, endocrinology, immunology, galvanic skin response (GSR), single-cell recording, and studies of focal brain lesion patients. Animal models are also important to investigate the putative role of specific brain structures, circuits, or processes (e.g., the reward system and drug addiction). In addition, quantitative meta-analyses are important to move beyond idiosyncrasies of individual studies, and neurodevelopmental investigations can contribute to our understanding of brain-behavior associations. The two most popular forms of methods used in social neuroscience are fMRI and EEG. fMRI are very cost efficient and high in spatial resolution. However, they are low in temporal resolution and therefore, are best to discover pathways in the brain that are used during social experiments. fMRI have low temporal resolution (timing) because they read oxygenated blood levels that pool to the parts of the brain that are activated and need more oxygen. Thus, the blood takes time to travel to the part of the brain being activated and in reverse provides a lower ability to test for exact timing of activation during social experiments. EEG is best used when a researcher is trying to brain map a certain area that correlates to a social construct that is being studied. EEGs provide high temporal resolution but low spatial resolution. In which, the timing of the activation is very accurate but it is hard to pinpoint exact areas on the brain, researchers are to narrow down locations and areas but they also create a lot of "noise". Most recently, researchers have been using TMS which is the best way to discover the exact location in the process of brain mapping. This machine can turn on and off parts of the brain which then allows researchers to test what that part of the brain is used for during social events. However, this machine is so expensive that it is rarely used.
Note: Most of these methods can only provide correlations between brain mapping and social events (apart from TMS), a con of Social Neuroscience is that the research must be interpreted through correlations which can cause a decreased content validity. For example, during an experiment when a participant is doing a task to test for a social theory and a part of the brain is activated, it is impossible to form causality because anything else in the room or the thoughts of the person could have triggered that response. It is very hard to isolate these variables during these experiments. That is why self-reports are very important. This will also help decrease the chances of VooDoo correlations (correlations that are too high and over 0.8 which look like a correlation exists between two factors but actually is just an error in design and statistical measures). Another way to avoid this con, is to use tests with hormones which can infer causality. For example, when people are given oxytocin and placebos and we can test their differences in social behavior between other people. Using SCRs will also help isolate unconscious thoughts and conscious thoughts because it is the body's natural parasympathetic response to the outside world. All of these tests and devices will help social neuroscientists discover the connections in the brain that are used to carry out our everyday social activities.
Primarily psychological methods include performance-based measures that record response time and/or accuracy, such as the Implicit Association Test; observational measures such as preferential looking in infant studies; and, self-report measures, such as questionnaire and interviews.