Episodic memory in schizophrenia: the influence of strategy use on behavior and brain activation.
Individuals with schizophrenia demonstrate behavioral and neurobiological deficits in episodic memory. However, recent work suggests that episodic memory deficits in schizophrenia may be mitigated through specific encoding strategies. The current study directly compared brain activity and memory performance associated with two different verbal encoding orientations in the same group of schizophrenia participants, in order to more fully characterize the role of strategy in memory processing in this population. Participants included 18 individuals with schizophrenia and 15 healthy comparison participants. Participants encoded words under two conditions during separate fMRI scanning runs. During Incidental encoding, participants were required to make abstract/concrete judgments for each word. During Intentional encoding, participants were instructed to memorize each word for a later memory test. Free recall and a recognition task (utilizing the Remember/Know paradigm) were performed outside of the scanner. Consistent with prior work, schizophrenia participants recognized more words encoded Incidentally than Intentionally, although free recall remained substantially impaired. Schizophrenia participants were also less likely to give Remember judgments for old words and more likely to give Guess judgments for both old and new words. When functional magnetic resonance imaging data were examined, we found that Incidental encoding was associated with substantially fewer between-group differences (Control>Schizophrenia) than Intentional encoding. Furthermore, schizophrenia participants exhibited intact activity during encoding of items that were subsequently retrieved. Our results suggest that use of an Incidental encoding strategy improved recognition memory among individuals with schizophrenia and resulted in a pattern of encoding-related brain activity that was more similar to that seen in control participants. However, we found that Incidental encoding did not improve free recall in schizophrenia participants and abnormal brain activity in some regions was observed, despite improvements in recognition memory.
Bonner-Jackson
Aaron
A
Departments of Psychology and Psychiatry, Washington University, St. Louis, MO 63130, USA. abonnerj@artsci.wustl.edu
Yodkovik
Naomi
N
Csernansky
John G
JG
Barch
Deanna M
DM
D000328:Adult; D001921:Brain / Q000378:metabolism* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D033182:Intention; D007600:Judgment; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis / Q000209:etiology*; D009483:Neuropsychological Tests; D021641:Recognition, Psychology; D012559:Schizophrenia / Q000150:complications*; D014825:Vocabulary
Hippocampus. 2004;14(1):5-8
15058477
Am J Psychiatry. 2001 Jul;158(7):1114-25
11431234
Biol Psychiatry. 2003 Dec 1;54(11):1154-61
14643082
Arch Gen Psychiatry. 1999 Jul;56(7):639-44
10401510
Schizophr Res. 2000 May 25;43(1):33-46
10828413
Psychol Med. 1998 Sep;28(5):1049-62
9794012
J Abnorm Psychol. 1974 Feb;83(1):14-22
4812427
Brain. 2001 Feb;124(Pt 2):399-412
11157567
Nature. 1997 Aug 7;388(6642):582-5
9252188
Cereb Cortex. 2001 Dec;11(12):1150-60
11709486
Cereb Cortex. 2002 Oct;12(10):1048-56
12217968
Neuropsychol Rev. 2003 Jun;13(2):43-77
12887039
Biol Psychiatry. 2005 Jul 1;58(1):47-55
15992522
Biol Psychiatry. 2004 Apr 1;55(7):668-75
15038994
J Abnorm Psychol. 2002 Aug;111(3):478-94
12150424
Am J Psychiatry. 1999 Sep;156(9):1358-66
10484945
Brain Lang. 2002 Mar;80(3):287-95
11896642
Am J Psychiatry. 2003 Oct;160(10):1802-8
14514494
Magn Reson Med. 1995 May;33(5):636-47
7596267
Schizophr Res. 2006 Apr;83(2-3):121-30
16497485
Neuroimage. 2004 Apr;21(4):1337-49
15050559
Am J Psychiatry. 2004 Jun;161(6):1004-15
15169688
Am J Psychiatry. 2003 Jul;160(7):1305-12
12832246
Neuroimage. 1997 Oct;6(3):156-67
9344820
Nat Rev Neurosci. 2001 Jan;2(1):51-61
11253359
Br J Psychiatry. 2005 Dec;187:500-9
16319401
Biol Psychiatry. 2003 Jan 1;53(1):48-55
12513944
Am J Psychiatry. 1995 Dec;152(12):1737-42
8526239
J Neurosci. 1998 Mar 1;18(5):1841-7
9465008
Am J Psychiatry. 2005 Oct;162(10):1840-8
16199830
J Abnorm Psychol. 1978 Jun;87(3):303-13
681601
Psychol Med. 1997 Mar;27(2):383-93
9089831
Am J Psychiatry. 2003 May;160(5):911-8
12727695
Science. 1998 Aug 21;281(5380):1185-7
9712581
J Nerv Ment Dis. 1983 Jul;171(7):426-30
6864200
J Abnorm Psychol. 1984 May;93(2):172-7
6725750
Cortex. 2003 Sep-Dec;39(4-5):1009-26
14584564
Neuron. 2003 Aug 14;39(4):713-26
12925284
Neuroimage. 2005 Apr 15;25(3):653-60
15808966
J Abnorm Psychol. 1992 Aug;101(3):487-94
1500605
Cereb Cortex. 2001 Sep;11(9):837-48
11532889
J Cogn Neurosci. 2001 Apr 1;13(3):406-15
11371316
Science. 1998 Aug 21;281(5380):1188-91
9712582