Amnesia for Violent Offenses: Factors Underlying Memory Loss and Recovery

Article Figures & Data

Table 1

Offense Characteristics

Variable	Nonamnesic (n = 19)	Amnesic (n = 31)	χ^2/t	p
Index offense, n (%)
Homicide	15 (79%)	28 (90%)	0.50^*	0.48
Crime of passion, n (%)	3 (16%)	15 (48%)	5.43	0.025
Intoxication, n (%)
Alcohol	11 (58%)	18 (58%)	0.00	0.99
Drugs	4 (21%)	6 (19%)	0.00^*	1.00

Table 2

Neuropsychological Tests

Variable	Nonamnesic (n = 19)	Amnesic (n = 31)	χ^2/t	p
NART IQ, mean (SD)	106.21 (9.20)	108.23 (10.12)	−0.71	0.48
Weschler Logical Memory, mean (SD)^*
Immediate	27.95 (5.89)	24.55 (6.99)	1.77	0.08
Delayed	22.95 (7.55)	19.77 (7.26)	1.48	0.15
Camden Memory Tests, mean (SD)^*
Paired-Associate Learning (1)/24^†	19.00 (3.43)	18.42 (3.69)	0.56	0.58
Paired-Associate Learning (2)/24	22.74 (1.76)	22.10 (2.34)	1.03	0.31
Pictorial Recognition Memory /30	29.05 (1.31)	29.29 (1.37)	−0.61	0.55
Topographical Recognition Memory/30	25.42 (4.21)	24.61 (3.54)	0.73	0.47
Recognition of Words/25	24.68 (0.48)	24.55 (0.93)	0.59	0.56
Recognition of Faces/25	24.42 (0.69)	24.58 (0.67)	−0.81	0.42

Table 3

Psychometric Measures

Variable	Nonamnesic (n = 19)	Amnesic (n = 31)	χ^2/t	p
Peritraumatic Dissociation, mean (SD)
Including amnesia measure (PTD 1)	13.68 (5.53)	21.00 (5.68)	−4.38	<0.0001
Excluding amnesia measure (PTD 2)	12.11 (4.59)	17.54 (5.29)	−3.64	<0.001
Dissociative Experiences, mean (SD)	10.64 (9.91)	17.33 (14.56)	−1.76	0.08
Impact of Event Scale, mean (SD)
Total	33.22 (12.65)	32.61 (11.40)	0.17	0.86
Avoidance	15.61 (6.82)	15.29 (6.03)	0.17	0.87
Intrusion	17.61 (6.83)	17.32 (6.68)	0.15	0.89
Shame, mean (SD)
Total	39.11 (11.07)	44.23 (13.08)	−1.42	0.16
Characterological	17.63 (5.95)	20.81 (7.52)	−1.56	0.13
Behavioral	15.68 (5.21)	16.48 (5.27)	−0.52	0.60
Bodily	5.95 (2.78)	6.94 (2.99)	−1.17	0.25
Repressive coping, n (%)	11.0 (58%)	15.0 (48%)	0.43	0.51
MAS, mean (SD)	6.11 (4.14)	7.87 (5.05)	−1.28	0.21
MC, mean (SD)	19.26 (5.13)	18.19 (6.17)	0.63	0.53
Memory characteristics mean (SD)
Perceived	96.28 (9.42)	83.07 (17.13)	3.32	<0.0025
Imagined	21.22 (4.40)	19.67 (3.98)	1.23	0.23
Neutral	96.33 (9.59)	84.96 (18.31)	2.72	<0.01

P values in bold represent significant differences. PTD, peritraumatic dissociation. MAS, Manifest Anxiety Scale; MC, Marlowe-Crowne Social Desirability Scale.

Table 4

Length of the Amnesic Gap

Variable	Group 1 Never Amnesic (n = 19)	Group 2 Recovered Amnesic (n = 16)	Group 3 Still Amnesic (n = 15)
Time of offense (minutes)
Mean (SD)	0	668.1 (1439.8)	58.3 (117.8)
Median	0	120.0	1.0
Seven year follow-up (minutes)
Mean (SD)	0	363.2 (1114.4)	58.3 (117.8)
Median	0	0.1	1.0
Degree of memory return, %
Complete, mean (SD)		6 (37.5)	0
Partial, mean (SD)		10 (62.5)	0

Table 5

Comparison of Long vs. Short Amnesic Gaps and Recovered vs. Nonrecovered Amnesic Participants

Variable	Long vs. Short Amnesic Gap χ^2/t (p)	Recovered vs. Nonrecovered χ^2/t (p)
Blackouts	3.77 (0.05)^*	7.43 (<0.01)
Alcohol dependence	3.65 (0.06)^*	3.04 (0.08)
Alcohol intoxication	0.009 (0.93)	0.88 (0.35)
Shame
Characterological	−1.14 (0.26)	1.90 (0.07)
Behavioral	−2.48 (<0.025)	0.76 (0.45)
MAS	−0.27 (0.79)	1.94 (0.06)
PTD excluding amnesia	−3.24 (<0.005)	1.08 (0.29)
Tariff	−2.46 (<0.025)	0.60 (0.56)

Table 6

Quality of Current Memory in the Three Groups

Variable	Group 1 Never Amnesic (n = 19)	Group 2 Recovered Amnesic (n = 16)	Group 3 Still Amnesic (n = 15)	χ^2/F	p
Memory characteristics, mean (SD)
Perceived	96.28 (9.42)	87.07 (14.54)	78.08 (19.38)	5.91	<0.005
Imagined	21.22 (4.40)	19.07 (3.26)	20.42 (4.78)	1.10	0.34
Neutral	96.33 (9.59)	89.33 (20.46)	79.50 (14.19)	4.45	<0.025