In the experiment reported here, we examined the neurodevelopmental basis of math anxiety by investigating brain response and connectivity during arithmetic problem solving in 7- to 9-year-old children. We showed, for the first time, that in children as young as 7 to 9 years of age, math anxiety is associated with hyperactivity and abnormal effective connectivity of the amygdala, a brain region associated with processing negative emotions and fearful stimuli (Phelps & LeDoux, 2005
). Furthermore, children with high math anxiety also showed distinct multivoxel patterns of neural activity within the amygdala, above and beyond overall differences in signal level.
These results provide converging evidence for aberrant processing within local functional circuits in the amygdala of children with high math anxiety. Children with high math anxiety also showed reduced responses in cortical and subcortical areas that have been consistently associated with mathematical and numerical reasoning in children and adults (Menon, Rivera, White, Glover, & Reiss, 2000
). These differences were related to arithmetic complexity and were independent of sensory, motor, decision-making, or response-selection processes. Additional analysis using SEMA scores as a continuous variable confirmed the observed pattern of increased right basolateral amygdala responses and decreased fronto-parietal activation with math anxiety. Furthermore, these effects occurred independently of individual differences in trait anxiety, working memory, and performance.
Our findings suggest that math anxiety is associated with aberrant activity in the right amygdala. The recent availability of cytoarchitectonic maps based on the spatial distribution of cortical and subcortical neurons provided more detailed information about amygdala subregions involved in math anxiety (Amunts et al., 2005
). Using these maps, we identified the basolateral nucleus as the most prominent site of hyperactive amygdala response in our study. The basolateral nucleus of the amygdala plays an important role in learned fear, as demonstrated by classical conditioning studies in healthy adults (Buchel, Dolan, Armony, & Friston, 1999
; Phelps, Delgado, Nearing, & LeDoux, 2004
). Our study extends these findings to problem-solving situations outside the traditional experimental contexts involving viewing fearful or angry faces (McClure et al., 2007
), and our results further suggest that these amygdala regions are specifically involved in anxiety experienced during math problem solving.
Network-level analysis (Bressler & Menon, 2010
; Rowe, 2010
) provided novel insights into impaired functional circuits underlying math anxiety in children, and two findings are noteworthy here. First, the right amygdala showed greater effective connectivity with the ventromedial prefrontal cortex in the HMA group than in the LMA group. Previous studies in adults have suggested that the ventromedial prefrontal cortex regulates negative emotions by modulating amygdala activity (Etkin, Prater, Hoeft, Menon, & Schatzberg, 2010
; Etkin & Wager, 2007
). Enhanced effective connectivity between these regions may facilitate compensatory mechanisms that allowed children with high math anxiety to perform well, albeit at a lower level than children with low math anxiety. Second, the posterior parietal cortex regions known to be involved in numerical and math problem solving (Wu et al., 2009
) also showed reduced effective connectivity with amygdala regions that were hyperactive in children with high math anxiety. In conjunction with this, children with high math anxiety showed weaker activation in the posterior parietal cortex than did children with low math anxiety.
Thus, in children in the LMA group, the amygdala was coupled with brain areas that facilitate efficient task processing, whereas in children in the HMA group, the amygdala showed greater coupling with cortical regions involved in processing and regulating negative emotions. An emerging body of research suggests that the amygdala is involved in complex cognitive-emotional behaviors arising from its dynamic interactions with multiple brain areas (Pessoa, 2008
). Our findings are consistent with this view and suggest that hyperactive amygdala function contributes to aberrant functional interactions during mathematical problem solving.
Our findings support the notion that math anxiety is stimulus- and situation-specific. Amygdala hyperactivity in the HMA group was observed in conjunction with lower problem-solving accuracy, despite the fact that the HMA group was matched with the LMA group on multiple domain-general measures, including IQ, working memory, reading, and trait anxiety. One mechanism by which anxiety is thought to influence performance is through reduced capacity for working memory, attention, and cognitive-control processes engaged during math problem solving (Beilock & Decaro, 2007
). Two key results support this interpretation. First, compared with the LMA group, children in the HMA group showed reduced responses in regions involved in working memory and attention, including the dorsolateral prefrontal cortex, presupplementary motor area, and basal ganglia (Chang, Crottaz-Herbette, & Menon, 2007
). Second, compared with children in the LMA group, children in the HMA group also showed reduced responses in posterior parietal cortex regions known to play a critical role in numerical and mathematical cognition (Rivera et al., 2005
; Wu et al., 2009
In both children and adults, functional neuroimaging studies have consistently implicated the intraparietal sulcus, within the posterior parietal cortex, as a region specifically involved in the representation and manipulation of numerical quantity (Ansari, 2008
; Dehaene, Piazza, Pinel, & Cohen, 2003
). Performance on mathematical information processing also critically involves activation and deactivation in a more distributed network of regions, such as the superior parietal lobule and the angular gyrus (Delazer et al., 2003
; Menon et al., 2000
; Wu et al., 2009
). These observations support our hypothe- sis that math anxiety is associated with reduced cognitive information-processing resources during arithmetic task performance in the developing brain.
It is remarkable that cognitive information-processing deficits arising from math anxiety can be traced to brain regions and circuits that have been consistently implicated in specific phobias and generalized anxiety disorders in adults. In this context, it is also noteworthy that children as young as 7 to 9 years of age can consciously report on their own anxiety in situations involving mathematical problem solving and that the effects of this subjective measure can be traced to individual differences in amygdala response and connectivity. Our findings not only emphasize parallels between math anxiety and other anxiety disorders but also validate math anxiety as a genuine type of stimulus and situation-specific anxiety.
Our study provides new insights into the neurobiological mechanisms and developmental basis of math anxiety in children and highlights the importance of assessing math anxiety at a young age. Brain-imaging data can be particularly useful in the identification of domain-specific and domain-general brain systems related to math anxiety; these identifications can, in turn, be used to design remediation strategies based on treatments that work on other phobias. In addition, studies such as ours can also provide crucial information on how problem solving and reasoning are affected by math and performance anxiety. Further elucidation of the relationship between math anxiety and general academic anxiety as well as the neurodevelopmental mechanisms underlying math anxiety can spur new ways of thinking about early treatment of a disability that has significant implications for an individual’s long-term academic and professional success.