The mind is different from the brain, just as psychology is different from biology. Although mental processes are associated with some biochemical/neurological operations, some researchers and the popular media have misrepresented the association between the two systems as the causal relation (biochemical changes cause psychological experiences) or simply seen the two as the same.
With the growing use of psychophysiological measures such as fMRI, PET, EEG, MEG, and optical neuroimaging, it has become pervasive to hear that biological events underlie (are more fundamental than) psychological events. For example, announcements such as "depression is a chemical imbalance" or "schizophrenia is a brain disease" became the mainstream during the past two decades. Neuroimaging has also been used to explain political or voting behaviors or attitudes, criminal behavior or other social interactions (e.g., Miller, 2010). Although some people believe that neuroimaging or biochemical processes provide the true understanding of the human mind, on the other side of the debate are scientists who are deeply skeptical of placing too much confidence in neuroscience and are offended by the premature claims (Diener, 2010).
Fortunately, some psychologists (e.g., Beck, 2010; Gernsbacher, 2010; Miller, 2010) have identified major problems with the claim that "biological events underlie the psychological events." Their main points can be summarized as the follows:
First, Correlation is not causation. The reverse relation (psychological events cause biological events) is equally or more likely. Biological events unfold along with the psychological events, but thinking, decision-making, problem solving and other cognitive function or dysfunction, emotional or motivational regulation, and other mental health or mentally ill symptoms are psychological. Such statements that psychological events are nothing more than brain events or the brain is the seat of our drives, temperaments and thought are logically erroneous. The biological approach, including research based on functional magnetic resonance (fMRI), magnetoencephalography (MEG), or electroencephalography (EEG) or on chemical imbalance, endocrine, genetic, immunological, or autonomic measures, may identifies some biological changes when people are engaged in mental activities, but it does not show that biological changes cause psychological experiences. In fact, the reverse may be true.
For example, research has show that after aerobic exercise, there were structural and functional brain changes. One does not have depression because one has a chemical imbalance, it is equally likely that being depressed causes chemical imbalance, just as one first sees the view as beautiful before gasping but one does not find the view beautiful because one gasps (Miller, 2010). Both pharmacological and psychological treatments (e.g., psychotherapy) can lead to changes in brain activity, as assessed by positron emission tomography (PET) or EEG. Reviews of studies of cognitive behavioral therapy or other learning activities (e.g., working-memory training) show that they lead to fMRI-recorded brain changes. In addition, PTSD-related trauma has been shown as cause brain changes (Miller, 2010).
Second, there is no specific correspondence between brain states and psychological states.
For instance, researchers readily interpret activation in the amygdala as reflecting the intense attachment, vigilant protectiveness, and empathy that characterize normal maternal attachment when the research subjects are mothers looking at photos of their children, whereas they construe activation in the same region as suggesting sexual/aggressive behavior when the participants are boyfriends listening to sentences such as "my girlfriend gave a gorgeous birthday present to her ex-boyfriend" (See Gernsbacher, 2010). There is likely an indefinite set of potential neural implementations of a given psychological phenomenon. Conversely, a given neural circuit may serve different psychological functions at different times or in different individuals (Miller, 2010).
A related issue is that the localization of the brain region for a specific psychological activity is problematic. For example, the hippocampus appears to be crucially involved in relational memory, but the hippocampus activity is not the same as memory. They have different meanings. Research with fMRI or MEG has not demonstrated that the memory deficit is located in the hippocampus. Memory deficits are functional impairments that are conceived in cognitive, computational, and overt behavioral terms, not in biological terms (Miller, 2010).
Third, there is a common tendency to confuse biological with innate (Beck, 2010).
A difference in the brain between two groups in no way indicates that the behavior under study is not learned. In fact, all learned behaviors will in some way change the brain.
According to Beck (2010), nonexperts and the mass media are "fooled" by scientific-sounding, but uninformative, neuroscience language because people tend to have blind, misguided confidence in biological data and find brain images and neuroscience language more convincing than results that make no reference to the brain. People are also attracted to the deceptively simply messages they afford. The emphasis that biology underlies psychology is promoted by additional factors: the business interest of pharmaceutical companies and some political pressures.
In short, fundamentally psychological concepts require fundamentally psychological explanations. Observations about biological phenomena can richly inform, but not replace, psychological explanations (Miller, 2010).
Beck, D. M. (2010). The appeal of the brain in the popular press. Perspectives on Psychological Science, 5, 762-766. doi: 10.1177/1745691610388779
Diener, E. (2010). Neuroimaging: voodoo, new phrenology, or scientific breakthrough? Introduction to special section on fMRI. Perspectives on Psychological Science, 5, 714-715.
Gernsbacher, M. A. (2010). Stigma from psychological science: Group differences, not deficits-introduction to stigma special section. Perspectives on Psychological Science, 5, 687. doi: 10.1177/1745691610388767
Miller; G. A. (2010). Mistreating psychology in the decades of the brain. Perspectives on Psychological Science, 5, 716-743. doi: 10.1177/1745691610388774