Table 5.

Genetic and Environmental Correlations Between Verbal Fluency and Executive Functions

Fluency Measure	Common EF		Updating-/WM- Specifica		Shifting-Specific
	rg	re	rg	re	rg	re
Age 17
General Fluency	0.37	0.84	0.54	-	−0.11	−0.54
	[.22, .54]	[.27, .99]	[.39, .74]		[−.30, .07]	[−.86, −.11]
Semantic-Specific	0.03	0.14	0.38	-	0.30	0.58
	[−.21, .24]	[−.39, .76]	[.11, .64]		[.06, .57]	[.15, 1.0]
Age 56
General Fluency	0.71	0.20	0.40	0.10	-	-
	[.47, .95]	[−.17, .58]	[.26, .58]	[−.29, .46]
Semantic-Specific	0.53	0.27	0.02	0.17	-	-
	[.11, .87]	[−.27, .93]	[−.26, .26]	[−.41, .72]

Note: Genetic (r_g) and environmental (r_e) correlations between executive functions and verbal fluency (and their 95% confidence intervals) are displayed in adolescents (top) and middle-aged adults (bottom). The total variance explained by genetic (a²) and nonshared environmental influences (e²) were nearly identical to those displayed in Figures 2 and 3. Shared environmental correlations were not estimated because, in all cases, one or both variables had no evidence for shared environmental influences. Nonshared environmental correlations between the Updating-Specific factor and fluency factors (age 17) were not estimated because the environmental estimate on the Updating-Specific factor was also zero (see Figure 2a). Genetic and environmental correlations were not estimated directly but computed from the output of the Cholesky decomposition. Factor loadings and residual ACEs on individual tasks are also not displayed, but were similar to those in Figures 2 and 3. Also not displayed, there were implied correlations between General Fluency and Semantic-Fluency through their overlap with EFs (r_g=.18, r_e=−.20 at age 17, r_g=.39, r_e=.07 at age 56). Both models fit well, χ²(663)=826.24, p<.001, RMSEA=.034, CFI=.938 for age 17, χ²(565)=637.92, p=.018, RMSEA=.019, CFI=.985 for age 56. Significant correlations are displayed in bold (p < .05).

^aindicates Updating-Specific at age 17 but Working Memory-Specific at age 56.