Table 5.

Statistical effects of monoamine metabolite levels (ng/mg protein) in select regions of the auditory telencephalon (see Table 3 for abbreviations) and song control system (see Table 4 for abbreviations) on song count (n = 16 males for dopamine metabolite in HVC; n = 18 males for all other monoamine metabolites). Comparisons were made between the directions of the significant relationships (i.e. positive or negative correlations) and the direction of the previously reported significant relationships between the monoamine metabolite of interest and either song environment or mean song length.

Independent Variables	Estimate	Standard Error	z Score	p-value
Norepinephrine metabolite in CMM	−0.1485	0.1752	−0.85	> 0.2
Intercept	3.2895	0.3057	10.76	< 0.001
Serotonin metabolite in CMM	0.4769	0.0552	8.64	< 0.001
Intercept	1.4405	0.3809	3.78	< 0.001
CONSISTENT with positive relationship with song environment
Serotonin metabolite in NCMd	0.1784	0.0278	6.43	< 0.001
Intercept	2.5322	0.3046	8.31	< 0.001
INCONSISTENT with negative relationship with mean song length
Dopamine metabolite in NCMv	0.2145	0.0348	6.16	< 0.001
Intercept	2.9645	0.2451	12.10	< 0.001
CONSISTENT with positive relationship with song environment
Serotonin metabolite in NCMv	0.0200	0.0100	5.78	< 0.001
Intercept	2.3342	0.2451	7.99	< 0.001
CONSISTENT with positive relationship with song environment
Dopamine metabolite in MAN	−0.0204	0.0366	−0.56	> 0.2
Intercept	3.1957	0.2833	11.28	< 0.001
Norepinephrine metabolite in Area X	−0.5311	0.1469	−3.61	< 0.001
Intercept	3.5351	0.2633	13.43	< 0.001
CONSISTENT with negative correlation with mean song length
Dopamine metabolite in Area X	0.0020	0.0010	2.15	0.032
Intercept	2.8397	0.3128	9.08	< 0.001
INCONSISTENT with negative correlation with mean song length
Dopamine metabolite in HVC	−0.0217	0.1763	−0.12	> 0.2
Intercept	3.1811	0.2879	11.05	< 0.001