Location
Banissy, M.J., Kanai, R., Walsh, V., & Rees, G. (2012). Inter-individual differences in empathy are reflected in
human brain structure. NeuroImage, 62 , 2034/C02039.
Results and Comments
MRI measures neuroanatomical structures that subserve empathy. Taken together, the cognitive component of
empathy is associated with grey matter volume of the ventral medial Prefrontal Cortex (vmPFC), whereas the
affective component of empathy is associated with grey matter volume of the inferior frontal gyrus, insula and
precuneus. The MRI cannot show the empathic process in action. The extent to which the size of a given brain
structure reflects a particular level of empathy, remains to be determined.
Functional Magnetic Resonance Imaging (fMRI)
(Singer, 2006 ).
Variable
Functional magnetic resonance imaging (fMRI) is an extension of MRI in which high resolution images of
activity levels in neural structures are obtained. Whereas MRI provides images of structural brain anatomy, fMRI
provides real-time images of brain activity by detecting increased blood supply and metabolic function (Blood
Oxygen Level Dependence or BOLD).
Description
A common technique in fMRI is blood oxygen level dependency (BOLD), which measures the hemodynamic
response related to energy use in neurons. Those neurons that are more active will consume more oxygen. fMRI
measures are used with tasks or stimuli that elicit empathy (e.g., PVP) and the corresponding brain activation is
measured. Like the MRI, fMRI has excellent spatial resolution (approximately 2 mm), but has comparatively
poorer temporal resolution (500 to 1000 ms). Another technique that produces spatial representations of active
neurons is positron emission tomography (PET). However, this method has not been used extensively in empa-
thy research (e.g., see Ruby & Decety, 2004; Shamay-Tsoory et al., 2005 ). Research using fMRI reveal the follow-
ing brain regions are associated with the empathic response: medial, dorsal medial, ventromedial and
ventrolateral prefrontal cortex ( Kra¨mer, Mohammadi, Don ˜amayor, Samii, & Mu ¨nte, 2010; Lawrence et al., 2006;
Seitz et al., 2008 ), superior temporal sulcus ( Kra¨mer et al., 2010 ), presupplementary motor area ( Seitz et al., 2008;
Lawrence et al., 2006 ), insula and supramarginal gyrus ( Lawrence et al., 2006; Carr, Iacoboni, Dubeau, Mazziotta,
& Lenzi, 2003 ), and amygdala ( Carr et al., 2003 ). Some of these findings have been extended to children ( Pfeifer,
Iacoboni, Mazziotta, & Dapretto, 2008 ).
Sample
As with MRI, due to the use of specialized equipment and the time consuming testing protocol, empathy
assessment using fMRI has typically used small sample sizes. In addition, it is also necessary that the participants
are screened to rule out the potential influence of a range of other factors on the measurements. Screening is
done for history of psychiatric or neurological disorders, use of medications that affect central nervous system
function, head trauma, substance abuse, and other serious medical conditions. It is also standard practice that
researchers state the number of right handed participants due to the laterality of brain functions. In many fMRI
studies, IQ scores and confirmation of normal or corrected to normal vision is also often stated.
Most research has used healthy adult participants recruited from the university population or local commu-
nity. This has included Carr et al. (2003) who used 7 males and 4 females with a mean age of 29.0 years
(range521 to 39), Lawrence et al. (2006) who used 6 males and 6 females with a mean age of 32.2 years
(SD59.95), Jackson et al. (2005) who used 8 males and 7 females with a mean age of 22.0 years ( SD52.6 years),
Gazzola, Aziz-Zadeh, and Keysers (2006) who used 7 males and 9 females with a mean age of 31 years
(range525 to 45), Seitz et al. (2008) who used 7 males and 7 females with a mean age of 28.6 years ( SD55.5),
Hooker, Verosky, Germine, Knight, and D’Esposito (2010) who used 8 males and 7 females with a mean age of
21.0 years (range 518 to 25), Kra¨mer et al. (2010) who used 11 males and 6 females with a mean age of 27.8 years
(SD54.8). Unlike prior research that has used samples consisting of males and females, Nummenmaa et al.
(2008) used only females ( N510) with a mean age of 26 years ( SD55.6 years). The researchers cited maximizing278 10. MEASURES OF EMPATHY: SELF-REPORT , BEHAVIORAL, AND NEUROSCIENTIFIC APPROACHES
III. EMOTION REGULATION