Reduction in manual asymmetry and decline in fine manual dexterity in right-handed older adults with mild cognitive impairment

Figures & data

Table 1. Means and Standard Deviations of kinematics in both tasks by type of movement.

Right hand
	Reaching		Grasping		Transport		Inserting
	HC	MCI	HC	MCI	HC	MCI	HC	MCI
LinV	44.5(7.4)	43.8(7.1)	8.5(1.6)	8.9(1.9)	34.8(6.3)	32.0(5.0)	7.2(1.4)	7.1(1.5)
CV linV	.32(.07)	.28(.06)	.66(.08)	.69(.10)	.29(.07)	.28(.05)	.74(.09)	.75(.09)
PL	13.7(1.7)	12.7(1.5)	7.9(2.9)	8.8(2.5)	10.7(1.4)	9.6(1.3)	6.9(2.3)	7.4(2.7)
AngV	74.5(23.2)	60.7(19.8)	59.9(24.1)	45.8(15.8)	64.8(22.2)	58.1(21.6)	49.2(15.7)	44.0(17.8)
CV angV	.68(.13)	.51(.15)	.77(.09)	.69(.11)	.76(.11)	.58(.16)	.93(.13)	.73(.17)
Angle	41.3(8.6)	45.5(11.8)	37.3(12.3)	47.7(17.5)	56.1(7.7)	63.6(11.3)	46.0(9.3)	53.0(11.2)
CV angle	.14(.05)	.15(.09)	.24(.13)	.28(.16)	.10(.04)	.10(.05)	.22(.08)	.24(.12)
Left hand
	Reaching		Grasping		Transport		Inserting
	HC	MCI	HC	MCI	HC	MCI	HC	MCI
LinV	35.5(4.8)	42.1(7.2)	6.5(1.2)	8.1(1.9)	27.2(4.0)	28.4(5.8)	6.2(1.3)	6.7(1.3)
CV linV	.48(.07)	.32(.08)	.53(.07)	.69(.10)	.44(.05)	.33(.08)	.63(.09)	.74(.08)
PL	15.9(1.6)	13.6(2.0)	5.2(2.1)	7.6(1.7)	12.8(1.5)	10.4(2.2)	5.5(1.5)	8.3(2.8)
AngV	62.5(13.7)	54.0(16.7)	40.2(12.8)	45.8(15.8)	51.4(15.5)	48.2(17.7)	35.6(13.2)	40.0(17.1)
CV angV	.67(.11)	.51(.16)	.73(.09)	.69(.09)	.82(.10)	.56(.17)	.93(.15)	.77(.15)
Angle	35.6(8.4)	43.0(11.5)	31.0(11.1)	38.5(11.9)	47.3(7.5)	56.1(10.3)	41.9(9.4)	52.5(10.2)
CV angle	.19(.06)	.19(.10)	.20(.09)	.30(.15)	.15(.06)	.12(.05)	.20(.09)	.26(.11)

Note. HC = healthy controls. MCI = mild cognitive impairment. LinV = linear velocity (cm/s). PL = path length (cm). AngV = angular velocity (°/s). CV = coefficient of variation.

Figure 1. Note. Mean ± SE laterality indices for kinematic variables during Reaching (A) and Transport (B) showing significant group differences. HC = healthy controls. MCI = mild cognitive impairment. LinV = linear velocity (cm/s). PL = path length (cm). AngV = angular velocity (°/s). CV = coefficient of variation. p < 0.01**; p < 0.001***.

Figure 2. Note. Mean ± SE laterality indices for kinematic variables during Grasping (A) and Inserting (B) showing significant group differences. HC = healthy controls. MCI = mild cognitive impairment. LinV = linear velocity. PL = path length. AngV = angular velocity. CV = coefficient of variation. p < .05*; p < 0.01**; p < 0.001***.

Table 2. Group differences in laterality indices of kinematics.

	Reaching				Grasping				Transport				Inserting
	HC	MCI	F	η^2p	HC	MCI	F	η^2p	HC	MCI	F	η^2p	HC	MCI	F	η^2p
LinV	.11	.02	43.28***	.327	.13	.05	13.52***	.132	.12	.06	12.72***	.125	.08	.02	7.17**	.075
CV linV	–.21	–.06	52.13***	.369	.11	.01	37.68***	.297	–.21	–.08	39.51***	.307	.08	.01	18.86***	.175
PL	–.07	–.03	10.83**	.108	.21	.07	24.18***	.214	–.09	–.03	10.63**	.107	.08	–.06	19.78***	.182
AngV	.08	.05	.36	.004	.13	.05	4.21*	.045	.10	.09	.10	.001	.17	.06	7.45**	.007
CV angV	.01	.01	.02	.001	.03	–.01	3.16	.034	–.04	.01	2.85	.031	–.01	–.03	2.21	.024
Angle	.08	.03	2.47	.027	.10	.09	.01	.000	.09	.06	1.34	.015	.05	.01	4.34*	.047
CV angle	–.15	–.12	.31	.003	.09	–.05	5.32*	.056	–.19	–.13	1.24	.014	.06	–.04	4.54*	.048

Note. HC = healthy controls. MCI = mild cognitive impairment. LinV = linear velocity. PL = path length. AngV = angular velocity. CV = coefficient of variation. *** p < .001, ** p < .01, * p < .05. Df = 89 for all comparisons.

Table 3. Bivariate correlations between right–left hand kinematic outcomes and comparisons by group.

Kinematic variables	Reaching			Grasping			Transport			Inserting
	r HC	r MCI	p	r HC	r MCI	p	r HC	r MCI	p	r HC	r MCI	p
Linear velocity	0.615	0.667	NS	0.350	0.478	NS	0.634	0.577	NS	0.593	0.449	NS
CV linear velocity	0.324	0.549	NS	0.296	0.495	NS	0.342	0.447	NS	0.079	0.278	NS
Path length	0.364	0.665	0.027	0.640	0.322	0.026	0.310	0.468	NS	0.385	0.568	NS
Angular velocity	0.207	0.216	NS	0.375	0.401	NS	0.115	0.492	0.026	0.558	0.327	NS
CV angular velocity	0.233	0.374	NS	0.143	0.342	NS	0.134	0.522	0.021	0.242	0.534	NS
Angle	0.355	0.330	NS	0.005	0.215	NS	0.208	0.462	NS	0.622	0.507	NS
CV angle	0.057	0.273	NS	0.061	0.323	NS	−0.007	0.375	0.038	0.623	0.559	NS

Note. HC = healthy controls. MCI = mild cognitive impairment. r = Pearson correlation coefficient. CV = coefficient of variation.

Data availability statement

The datasets for this article cannot be made publicly available due to restrictions of the Norwegian Research Ethics Committee. However, upon reasonable request, summary statistics can be obtained from the corresponding author (CRA).