Table 1. Performance of spectral analysis algorithms in simulation dataa.

Whole brainb	K1 (mL g−1 min−1)			Vb			λ			rCPS (nmol g−1 min−1)
‘True' value	0.050			0.068			0.764			1.69
	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)
Unfiltered	0.081±0.047	61.4%	94.5%	0.065±0.005	−5.0%	7.3%	0.851±0.073	11.3%	9.6%	1.27±0.44	−24.5%	25.9%
Highpass EC filter	0.049±0.003	−2.4%	6.0%	0.072±0.006	5.2%	8.8%	0.746±0.037	−2.4%	4.8%	1.80±0.25	6.9%	14.6%
With restricted grid	0.051±0.001	1.8%	2.0%	0.068±0.001	−0.6%	1.5%	0.773±0.006	1.1%	0.8%	1.64±0.08	−3.0%	4.6%
SAIF	0.051±0.001	0.9%	1.9%	0.068±0.001	−0.5%	1.9%	0.762±0.006	−0.3%	0.8%	1.72±0.05	2.0%	2.7%
Frontal cortexc	K1 (mL g−1 min−1)			Vb			λ			rCPS (nmol g−1 min−1)
‘True' value	0.051			0.071			0.757			1.79
	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)
Unfiltered	0.087±0.060	70.1%	118.1%	0.067±0.006	−6.1%	8.5%	0.869±0.083	14.8%	11.0%	1.14±0.59	−36.0%	33.2%
Highpass EC filter	0.050±0.002	−2.2%	3.9%	0.075±0.005	5.1%	7.0%	0.721±0.038	−4.8%	5.0%	2.11±0.31	18.0%	17.6%
With restricted grid	0.052±0.001	1.7%	2.0%	0.071±0.002	−0.5%	2.8%	0.750±0.008	−0.9%	1.1%	1.88±0.06	5.3%	3.2%
SAIF	0.052±0.001	1.4%	2.1%	0.071±0.001	−0.7%	1.4%	0.764±0.008	0.9%	1.0%	1.75±0.06	−2.3%	3.3%
Corona radiatad	K1 (mL g−1 min−1)			Vb			λ			rCPS (nmol g−1 min−1)
‘True' value	0.031			0.032			0.792			0.89
	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)
Unfiltered	0.074±0.064	137.5%	210.1%	0.027±0.007	−16.8%	22.2%	0.887±0.075	11.9%	9.5%	0.66±0.27	−26.2%	30.3%
Highpass EC filter	0.029±0.003	−6.9%	9.9%	0.036±0.005	11.0%	15.8%	0.762±0.049	−3.8%	6.2%	0.99±0.18	11.2%	20.2%
With restricted grid	0.032±0.001	2.7%	3.3%	0.032±0.002	−1.4%	6.2%	0.799±0.012	0.8%	1.5%	0.87±0.06	−2.5%	6.2%
SAIF	0.032±0.001	1.5%	3.9%	0.032±0.002	−1.7%	5.7%	0.793±0.012	0.1%	1.5%	0.90±0.05	1.1%	5.4%
Hippocampuse	K1 (mL g−1 min−1)			Vb			λ			rCPS (nmol g−1 min−1)
‘True' value	0.036			0.082			0.674			1.91
	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)	Estimated value (mean±s.d.)	Bias (%)	RMSE (%)
Unfiltered	0.165±0.197	356.2%	649.7%	0.067±0.021	−18.7%	31.6%	0.838±0.137	24.4%	31.8%	1.34±0.76	−29.8%	49.8%
Highpass EC filter	0.033±0.003	−8.4%	12.0%	0.089±0.007	8.1%	12.0%	0.578±0.086	−14.3%	19.1%	2.71±0.75	42.1%	57.6%
With restricted grid	0.037±0.002	1.6%	0.5%	0.081±0.005	−1.7%	0.2%	0.659±0.032	−2.2%	0.1%	2.07±0.21	8.5%	0.1%
SAIF	0.037±0.002	1.9%	6.7%	0.080±0.005	−1.9%	6.0%	0.668±0.032	−0.9%	4.8%	2.00±0.20	4.8%	11.7%

rCPS, regional rates of cerebral protein synthesis; RMSE, root mean square error; SAIF, spectral analysis with iterative filter.

^aNumber of noise realizations=1000.

^bSimulation parameters: w_aK_1a=0.042 mL g⁻¹ min⁻¹; w_bK_1b=0.0082 mL g⁻¹ min⁻¹; k_2a+k_3a=0.15 min⁻¹; k_2b+k_3b=0.029 min⁻¹; k_4a=0.047 min⁻¹; k_4b=0.0089 min⁻¹; V_b=0.068; noise level N=0.20 nCi min/mL.

^cSimulation parameters: w_aK_1a=0.044 mL g⁻¹ min⁻¹; w_bK_1b=0.0075 mL g⁻¹ min⁻¹; k_2a+k_3a=0.13 min⁻¹; k_2b+k_3b=0.018 min⁻¹; k_4a=0.042 min⁻¹; k_4b=0.0059 min⁻¹; V_b=0.071; noise level N=0.25 nCi min/mL.

^dSimulation parameters: w_aK_1a=0.021 mL g⁻¹ min⁻¹; w_bK_1b=0.0102 mL g⁻¹ min⁻¹; k_2a+k_3a=0.15 min⁻¹; k_2b+k_3b=0.041 min⁻¹; k_4a=0.040 min⁻¹; k_4b=0.0107 min⁻¹; V_b=0.032; noise level N=0.36 nCi min/mL.

^eSimulation parameters: w_aK_1a=0.020 mL g⁻¹ min⁻¹; w_bK_1b=0.016 mL g⁻¹ min⁻¹; k_2a+k_3a=0.115 min⁻¹; k_2b+k_3b=0.022 min⁻¹; k_4a=0.055 min⁻¹; k_4b=0.010 min⁻¹; V_b=0.082; noise level N=0.70 nCi min/mL.