Hostname: page-component-76fb5796d-45l2p Total loading time: 0 Render date: 2024-04-29T12:16:38.876Z Has data issue: false hasContentIssue false

The processing of emotional prosody and semantics in schizophrenia: relationship to gender and IQ

Published online by Cambridge University Press:  22 October 2007

M. R. M. Scholten*
Affiliation:
Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Centre, Utrecht, The Netherlands
A. Aleman
Affiliation:
BCN NeuroImaging Centre, University of Groningen, Groningen, The Netherlands
R. S. Kahn
Affiliation:
Department of Psychiatry, Rudolf Magnus Institute of Neuroscience, University Medical Centre, Utrecht, The Netherlands
*
*Address for correspondence: M. R. M. Scholten, M.D., Ph.D., Department of Psychiatry, UMC Utrecht, P.O. Box 85500, 3508 GAUtrecht, Reference No. A 00.241, The Netherlands. (Email: mrmscholten@cs.com)

Abstract

Background

Female patients with schizophrenia are less impaired in social life than male patients. Because social impairment in schizophrenia has been found to be associated with deficits in emotion recognition, we examined whether the female advantage in processing emotional prosody and semantics is preserved in schizophrenia.

Method

Forty-eight patients (25 males, 23 females) and 46 controls (23 males, 23 females) were assessed using an emotional language task (in which healthy women generally outperform healthy men), consisting of 96 sentences in four conditions: (1) neutral-content/emotional-tone (happy, sad, angry or anxious); (2) neutral-tone/emotional-content; (3) emotional-tone/incongruous emotional-content; and (4) emotional-content/incongruous emotional-tone. Participants had to ignore the emotional-content in the third condition and the emotional-tone in the fourth condition. In addition, participants were assessed with a visuospatial task (in which healthy men typically excel). Correlation coefficients were computed for associations between emotional language data, visuospatial data, IQ measures and patient variables.

Results

Overall, on the emotional language task, patients made more errors than control subjects, and women outperformed men across diagnostic groups. Controlling for IQ revealed a significant effect on task performance in all groups, especially in the incongruent tasks. On the rotation task, healthy men outperformed healthy women, but male patients, female patients and female controls obtained similar scores.

Conclusion

The advantage in emotional prosodic and semantic processing in healthy women is preserved in schizophrenia, whereas the male advantage in visuospatial processing is lost. These findings may explain, in part, why social functioning is less compromised in women with schizophrenia than in men.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Aleman, A, Kahn, RS (2005). Strange feelings: do amygdala abnormalities dysregulate the emotional brain in schizophrenia? Progress in Neurobiology 77, 283298.Google ScholarPubMed
Aleman, A, Kahn, RS, Selten, J-P (2003). Sex differences in the risk of schizophrenia: evidence from meta-analysis. Archives of General Psychiatry 60, 565571.CrossRefGoogle ScholarPubMed
Allen, LS, Richey, MF, Chai, YM, Gorski, RA (1991). Sex differences in the corpus callosum of the living human being. Journal of Neuroscience 11, 933942.CrossRefGoogle ScholarPubMed
Andreasen, NC, Flaum, M, Arndt, S (1992). The Comprehensive Assessment of Symptoms and History (CASH). An instrument for assessing diagnosis and psychopathology. Archives of General Psychiatry 49, 615623.CrossRefGoogle ScholarPubMed
Barch, DM, Carter, CS, Cohen, JD (2004). Factors influencing Stroop performance in schizophrenia. Neuropsychology 18, 477484.CrossRefGoogle ScholarPubMed
Barch, DM, Carter, CS, Hachten, PC, Usher, M, Cohen, JD (1999). The ‘benefits’ of distractibility: mechanisms underlying increased Stroop effects in schizophrenia. Schizophrenia Bulletin 25, 749762.CrossRefGoogle ScholarPubMed
Baxter, LC, Saykin, AJ, Flashman, LA, Johnson, SC, Guerin, SJ, Babcock, DR, Wishart, HA (2003). Sex differences in semantic language processing: a functional MRI study. Brain and Language 84, 264272.CrossRefGoogle ScholarPubMed
Bell, EC, Willson, MC, Wilman, AH, Dave, S, Silverstone, PH (2006). Males and females differ in brain activation during cognitive tasks. Neuroimage 30, 529538.CrossRefGoogle ScholarPubMed
Bergemann, N, Mundt, C, Parzer, P, Jannakos, I, Nagl, I, Salbach, B, Klinga, K, Runnebaum, B, Resch, F (2005). Plasma concentrations of estradiol in women suffering from schizophrenia treated with conventional versus atypical antipsychotics. Schizophrenia Research 73, 357366.CrossRefGoogle ScholarPubMed
Besson, M, Magne, C, Schon, D (2002). Emotional prosody: sex differences in sensitivity to speech melody. Trends in Cognitive Science 6, 405407.CrossRefGoogle ScholarPubMed
Borod, JC, Martin, CC, Alpert, M, Brozgold, A, Welkowitz, J (1993). Perception of facial emotion in schizophrenic and right brain-damaged patients. Journal of Nervous and Mental Disease 181, 494502.CrossRefGoogle ScholarPubMed
Bozikas, VP, Kosmidis, MH, Anezoulaki, D, Giannakou, M, Andreou, C, Karavatos, A (2006). Impaired perception of affective prosody in schizophrenia. Journal of Neuropsychiatry and Clinical Neurosciences 18, 8185.CrossRefGoogle ScholarPubMed
Buchanan, RW, Holstein, C, Breier, A (1994). The comparative efficacy and long-term effect of clozapine treatment on neuropsychological test performance. Biological Psychiatry 36, 717725.CrossRefGoogle ScholarPubMed
Buchanan, TW, Lutz, K, Mirzazade, S, Specht, K, Shah, NJ, Zilles, K, Jancke, L (2000). Recognition of emotional prosody and verbal components of spoken language: an fMRI study. Brain Research. Cognitive Brain Research 9, 227238.CrossRefGoogle ScholarPubMed
Burton, LA, Henninger, D, Hafetz, J (2005). Gender differences in relations of mental rotation, verbal fluency, and SAT scores to finger length ratios as hormonal indexes. Developmental Neuropsychology 1, 493505.CrossRefGoogle Scholar
Collaer, ML, Hines, M (1995). Human behavioral sex differences: a role for gonadal hormones during early development? Psychological Bulletin 118, 55107.CrossRefGoogle ScholarPubMed
Condray, R, Steinhauer, SR, van Kammen, DP, Kasparek, A (2002). The language system in schizophrenia: effects of capacity and linguistic structure. Schizophrenia Bulletin 28, 475490.CrossRefGoogle ScholarPubMed
Corrigan, PW, Hirschbeck, JN, Wolfe, M (1995). Memory and vigilance training to improve social perception in schizophrenia. Schizophrenia Research 17, 257265.CrossRefGoogle ScholarPubMed
Cutting, J (1992). The role of right hemisphere dysfunction in psychiatric disorders. British Journal of Psychiatry 160, 583588.CrossRefGoogle ScholarPubMed
de Vignemont, F, Zalla, T, Posada, A, Louvegnez, A, Koenig, O, Georgieff, N, Franck, N (2006). Mental rotation in schizophrenia. Conscious Cognition 15, 295309.CrossRefGoogle ScholarPubMed
Diamond, MC (1989). Sex and the cerebral cortex. Biological Psychiatry 25, 823825.CrossRefGoogle ScholarPubMed
Driscoll, I, Hamilton, DA, Yeo, RA, Brooks, WM, Sutherland, RJ (2005). Virtual navigation in humans: the impact of age, sex, and hormones on place learning. Hormones and Behavior 47, 326335.CrossRefGoogle ScholarPubMed
Dubb, A, Gur, R, Avants, B, Gee, J (2003). Characterization of sexual dimorphism in the human corpus callosum. Neuroimage 20, 512519.CrossRefGoogle ScholarPubMed
Edwards, J, Jackson, HJ, Pattison, PE (2002). Emotion recognition via facial expression and affective prosody in schizophrenia: a methodological review. Clinical Psychology Review 22, 789832. Erratum in: Clinical Psychology Review (2002) 22, 1267–1285.CrossRefGoogle ScholarPubMed
Edwards, J, Pattison, PE, Jackson, HJ, Wales, RJ (2001). Facial affect and affective prosody recognition in first-episode schizophrenia. Schizophrenia Research 48, 235253.CrossRefGoogle ScholarPubMed
Epting, LK, Overman, WH (1998). Sex-sensitive tasks in men and women: a search for performance fluctuations across the menstrual cycle. Behavioral Neuroscience 112, 13041317.CrossRefGoogle ScholarPubMed
Frederikse, M, Lu, A, Aylward, E, Barta, P, Sharma, T, Pearlson, G (2000). Sex differences in inferior parietal lobule volume in schizophrenia. American Journal of Psychiatry 157, 422427.CrossRefGoogle ScholarPubMed
Frederikse, ME, Lu, A, Aylward, E, Barta, P, Pearlson, G (1999). Sex differences in the inferior parietal lobule. Cerebral Cortex 9, 896901.CrossRefGoogle ScholarPubMed
Fricchione, G, Sedler, MJ, Shukla, S (1986). Aprosodia in eight schizophrenic patients. American Journal of Psychiatry 143, 14571459.Google ScholarPubMed
Gandour, J, Tong, Y, Wong, D, Talavage, T, Dzemidzic, M, Xu, Y, Li, X, Lowe, M (2004). Hemispheric roles in the perception of speech prosody. Neuroimage 23, 344357.CrossRefGoogle ScholarPubMed
Geschwind, N, Galaburda, AM (1987). Cerebral Lateralization: Biological Mechanisms, Associations and Pathology. MIT Press: Cambridge, MA.Google Scholar
Goldstein, JM, Cohen, LS, Horton, NJ, Lee, H, Andersen, S, Tohen, M, Crawford, A, Tollefson, G (2002 b). Sex differences in clinical response to olanzapine compared with haloperidol. Psychiatry Research 110, 2737.CrossRefGoogle ScholarPubMed
Goldstein, JM, Lewine, RRJ (2000). Overview of sex differences in schizophrenia: where have we been and where do we go from here? In Women and Schizophrenia (ed. Castle, D. J., McGrath, J. J. and Kulkarni, J.), pp. 111153. Cambridge University Press: Cambridge, MA.Google Scholar
Goldstein, JM, Seidman, LJ, O'Brien, LM, Horton, NJ, Kennedy, DN, Makris, N, Caviness, VS, Faraone, SV, Tsuang, MT (2002 a). Impact of normal sexual dimorphisms on sex differences in structural brain abnormalities in schizophrenia assessed by magnetic resonance imaging. Archives of General Psychiatry 59, 154164.CrossRefGoogle ScholarPubMed
Gur, RC, Gunning-Dixon, F, Bilker, WB, Gur, RE (2002). Sex differences in temporo-limbic and frontal brain volumes of healthy adults. Cerebral Cortex 12, 9981003.CrossRefGoogle ScholarPubMed
Gur, RE, Kohler, C, Ragland, JD, Siegel, SJ, Bilker, WB, Loughead, J, Phend, N, Gur, RC (2003). Neurocognitive performance and clinical changes in olanzapine-treated patients with schizophrenia. Neuropsychopharmacology 28, 20292036.CrossRefGoogle ScholarPubMed
Häfner, H (2003). Gender differences in schizophrenia. Psychoneuroendocrinology 28 (Suppl. 2), 1754.CrossRefGoogle ScholarPubMed
Häfner, H, Maurer, K, Löffler, W, Fätkenheuer, B, an der Heiden, W, Riecher-Rössler, A, Behrens, S, Gattaz, W (1994). The epidemiology of early schizophrenia. Influence of age and gender on onset and early course. British Journal of Psychiatry 164 (Suppl. 23), 2938.CrossRefGoogle Scholar
Halari, R, Mehrotra, R, Sharma, T, Ng, V, Kumari, V (2006 b). Cognitive impairment but preservation of sexual dimorphism in cognitive abilities in chronic schizophrenia. Psychiatry Research 141, 129139.CrossRefGoogle ScholarPubMed
Halari, R, Sharma, T, Hines, M, Andrew, C, Simmons, A, Kumari, V (2006 a). Comparable fMRI activity with differential behavioural performance on mental rotation and overt verbal fluency tasks in healthy men and women. Experimental Brain Research 169, 114.CrossRefGoogle ScholarPubMed
Hall, JA (1978). Gender effects in decoding non-verbal cues. Psychological Bulletin 85, 845857.CrossRefGoogle Scholar
Hall, JA (1984). Non-verbal Sex Differences: Communication Accuracy and Expressive Style. John Hopkins University Press: Baltimore.CrossRefGoogle Scholar
Halpern, DF, LaMay, LM (2000). The smarter sex: a critical review of sex differences in intelligence. Educational Psychology Review 12, 229246.CrossRefGoogle Scholar
Harasty, J, Double, KL, Halliday, GM, Kril, JJ, McRitchie, DA (1997). Language-associated cortical regions are proportionally larger in the female brain. Archives of Neurology 54, 171176.CrossRefGoogle ScholarPubMed
Harvey, PD, Napolitano, JA, Mao, L, Gharabawi, G (2003). Comparative effects of risperidone and olanzapine on cognition in elderly patients with schizophrenia or schizoaffective disorder. International Journal of Geriatric Psychiatry 18, 820829.CrossRefGoogle ScholarPubMed
Hooker, C, Park, S (2002). Emotion processing and its relationship to social functioning in schizophrenia patients. Psychiatry Research 112, 4150.CrossRefGoogle ScholarPubMed
Iwanami, A, Kanamori, R, Isono, H, Okajima, Y, Kamijima, K (1996). Impairment of inhibition of unattended stimuli in schizophrenic patients: event-related potential correlates during selective attention. Neuropsychobiology 34, 5762.CrossRefGoogle ScholarPubMed
Jordan, K, Wustenberg, T, Heinze, HJ, Peters, M, Jancke, L (2002). Women and men exhibit different cortical activation patterns during mental rotation tasks. Neuropsychologia 40, 23972408.CrossRefGoogle ScholarPubMed
Kay, SR, Opler, LA, Fiszbein, A (1986). Positive and Negative Syndrome Scale (PANSS). MultiHealth Systems Inc.: North Tonawanda, NY.Google Scholar
Kimura, D (1999). Sex and Cognition. The MIT Press: Cambridge, MA.CrossRefGoogle Scholar
Kohler, CG, Turner, TH, Bilker, WB, Brensinger, CM, Siegel, SJ, Kanes, SJ, Gur, RE, Gur, RC (2003). Facial emotion recognition in schizophrenia: intensity effects and error pattern. American Journal of Psychiatry 160, 17681774.CrossRefGoogle ScholarPubMed
Kucharska-Pietura, K, David, AS, Dropko, P, Klimkowski, M (2002). The perception of emotional chimeric faces in schizophrenia: further evidence of right hemisphere dysfunction. Neuropsychiatry, Neuropsychology and Behavioral Neurology 15, 7278.Google ScholarPubMed
Leentjens, AF, Wielaert, SM, van Harskamp, F, Wilmink, FW (1998). Disturbances of affective prosody in patients with schizophrenia; a cross sectional study. Journal of Neurology, Neurosurgery and Psychiatry 64, 375378.CrossRefGoogle ScholarPubMed
Leitman, DI, Foxe, JJ, Butler, PD, Saperstein, A, Revheim, N, Javitt, DC (2005). Sensory contributions to impaired prosodic processing in schizophrenia. Biological Psychiatry 58, 5661.CrossRefGoogle ScholarPubMed
Leung, A, Chue, P (2000). Sex differences in schizophrenia: a review of the literature. Acta Psychiatrica Scandinavia 101 (Suppl.), 338.CrossRefGoogle Scholar
Linn, MC, Petersen, AC (1985). Emergence and characterization of sex differences in spatial ability: a meta-analysis. Child Development 56, 14791498.CrossRefGoogle ScholarPubMed
Maki, P, Rich, J, Rosenbaum, RS (2002). Implicit memory varies across the menstrual cycle: estrogen effects in young women. Neuropsychologia 40, 518529.CrossRefGoogle ScholarPubMed
Mandal, MK, Pandey, R, Prasad, AB (1998). Facial expressions of emotions and schizophrenia: a review. Schizophrenia Bulletin 24, 399412.CrossRefGoogle ScholarPubMed
McClure, EB (2000). A meta-analytic review of sex differences in facial expression processing and their development in infants, children, and adolescents. Psychological Bulletin 126, 424453.CrossRefGoogle ScholarPubMed
Mitchell, RL, Elliott, R, Barry, M, Cruttenden, A, Woodruff, PW (2004). Neural response to emotional prosody in schizophrenia and in bipolar affective disorder. British Journal of Psychiatry 184, 223230.CrossRefGoogle ScholarPubMed
Mitchell, TN, Free, SL, Merschhemke, M, Lemieux, L, Sisodiya, SM, Shorvon, SD (2003). Reliable callosal measurement: population normative data confirm sex-related differences. American Journal of Neuroradiology 24, 410418.Google ScholarPubMed
Moody, MS (1997). Changes in scores on the mental rotation test during menstrual cycle. Perceptual and Motor Skills 84, 955961.CrossRefGoogle ScholarPubMed
Mueser, K, Doonan, R, Penn, D, Blanchard, J, Bellack, A, Nishith, P, DeLeon, J (1996). Emotion recognition and social competence in chronic schizophrenia. Journal of Abnormal Psychology 105, 271275.CrossRefGoogle ScholarPubMed
Muller, U, Werheid, K, Hammerstein, E, Jungmann, S, Becker, T (2005). Prefrontal cognitive deficits in patients with schizophrenia treated with atypical or conventional antipsychotics. European Psychiatry 20, 7073.CrossRefGoogle ScholarPubMed
Murphy, D, Cutting, J (1990). Prosodic comprehension and expression in schizophrenia. Journal of Neurology, Neurosurgery and Psychiatry 53, 727730.CrossRefGoogle ScholarPubMed
Nelson, HE (1982). National Adult Reading Test (NART): Test Manual. NFER-Nelson: Windsor, UK.Google Scholar
Nestor, PG, Han, SD, Niznikiewicz, M, Salisbury, D, Spencer, K, Shenton, ME, McCarley, RW (2001). Semantic disturbance in schizophrenia and its relationship to the cognitive neuroscience of attention. Biological Psychology 57, 2346.CrossRefGoogle Scholar
Penn, D, Spaulding, W, Reed, D, Sullivan, M (1996). The relationship of social cognition toward behaviour in chronic schizophrenia. Schizophrenia Research 20, 327335.CrossRefGoogle Scholar
Poole, JH, Tobias, F, Vinogradow, S (2000). The functional relevance of affect recognition errors in schizophrenia. Journal of the International Neuropsychological Society 6, 649658.CrossRefGoogle ScholarPubMed
Raven, JC, Court, JH, Raven, J (1996). Standard Progressive Matrices: with Adult US Norms. Oxford Psychologists: Oxford.Google Scholar
Rilea, SL, Roskos-Ewoldsen, B, Boles, D (2004). Sex differences in spatial ability: a lateralization of function approach. Brain and Cognition 56, 332343.CrossRefGoogle ScholarPubMed
Roberts, JE, Bell, MA (2003). Two- and three-dimensional mental rotation tasks lead to different parietal laterality for men and women. International Journal of Psychophysiology 50, 235246.CrossRefGoogle ScholarPubMed
Ross, ED, Orbelo, DM, Cartwright, J, Hansel, S, Burgard, M, Testa, JA, Buck, R (2001). Affective-prosodic deficits in schizophrenia: comparison to patients with brain damage and relation to schizophrenic symptoms [corrected]. Journal of Neurology, Neurosurgery and Psychiatry 70, 597604. [Erratum in: Journal of Neurology, Neurosurgery and Psychiatry (2001) 71, 283.]CrossRefGoogle ScholarPubMed
Rossell, SL, Bullmore, ET, Williams, SC, David, AS (2002). Sex differences in functional brain activation during a lexical visual field task. Brain and Language 80, 97105.CrossRefGoogle ScholarPubMed
Schirmer, A, Kotz, SA (2003). ERP evidence for a sex-specific Stroop effect in emotional speech. Journal of Cognitive Neuroscience 15, 11351148.CrossRefGoogle ScholarPubMed
Schirmer, A, Kotz, SA, Friederici, AD (2002). Sex differentiates the role of emotional prosody during word processing. Cognitive Brain Research 14, 228233.CrossRefGoogle ScholarPubMed
Schirmer, A, Kotz, SA, Friederici, AD (2005). On the role of attention for the processing of emotions in speech: sex differences revisited. Brain Research. Cognitive Brain Research 24, 442452.CrossRefGoogle ScholarPubMed
Schirmer, A, Zysset, S, Kotz, SA, Yves von Cramon, D (2004). Gender differences in the activation of inferior frontal cortex during emotional speech perception. Neuroimage 21, 11141123.CrossRefGoogle ScholarPubMed
Schlaepfer, TE, Harris, GJ, Tien, AY, Peng, L, Lee, S, Pearlson, GD (1995). Structural differences in the cerebral cortex of healthy female and male subjects: a magnetic resonance imaging study. Psychiatry Research 61, 129135.CrossRefGoogle ScholarPubMed
Schmand, B, Lindeboom, J, van Harskamp, F (1992). Dutch Reading Test for Adults: Manual [Nederlandse leestest voor volwassenen: handleiding; NLV]. Swets & Zeitlinger: Lisse.Google Scholar
Scholten, M, Aleman, A, Montagne, B, Kahn, R (2005). Schizophrenia and processing of facial emotions: sex matters. Schizophrenia Research 78, 6167.CrossRefGoogle ScholarPubMed
Shaywitz, BA, Shaywitz, SE, Pugh, KR, Constable, RT, Skudlarski, P, Fulbright, RK, Bronen, RA, Fletcher, JM, Shankweiler, DP, Katz, L, Gore, JC (1995). Sex differences in the functional organization of the brain for language. Nature 373, 607609. Comment in: Nature (1995) 373, 561–562.CrossRefGoogle ScholarPubMed
Sheehan, DV, Lecrubier, Y, Sheehan, KH, Amorim, P, Janavs, J, Weiller, E, Hergueta, T, Baker, R, Dunbar, GC (1998). The Mini-International Neuropsychiatric Interview (M.I.N.I.): the development and validation of a structured diagnostic psychiatric interview for DSM-IV and ICD-10. Journal of Clinical Psychiatry 59, 2233.Google ScholarPubMed
Shenton, ME, Dickey, CC, Frumin, M, McCarley, RW (2001). A review of MRI findings in schizophrenia. Schizophrenia Research 49, 152.CrossRefGoogle ScholarPubMed
Shepard, RN, Metzler, J (1971). Mental rotation of three-dimensional objects. Science 171, 701703.CrossRefGoogle ScholarPubMed
Siegel-Hinson, RI, McKeever, WF (2002). Hemispheric specialisation, spatial activity experience, and sex differences on tests of mental rotation ability. Laterality 7, 5974.CrossRefGoogle ScholarPubMed
Silverman, I, Phillips, K (1993). Effects of oestrogen changes during the menstrual cycle on spatial performance. Ethology and Sociobiology 4, 257270.CrossRefGoogle Scholar
Tong, Y, Gandour, J, Talavage, T, Wong, D, Dzemidzic, M, Xu, Y, Li, X, Lowe, M (2005). Neural circuitry underlying sentence-level linguistic prosody. Neuroimage 28, 417428.CrossRefGoogle ScholarPubMed
Vingerhoets, G, Berckmoes, C, Stroobant, N (2003). Cerebral hemodynamics during discrimination of prosodic and semantic emotion in speech studied by transcranial Doppler ultrasonography. Neuropsychology 17, 9399.CrossRefGoogle ScholarPubMed
Walder, D, Seidman, L, Cullen, N, Su, J, Tsuang, M, Goldstein, J (2006). Sex differences in language dysfunction in schizophrenia. American Journal of Psychiatry 163, 470477.CrossRefGoogle ScholarPubMed
Weiss, E, Siedentopf, CM, Hofer, A, Deisenhammer, EA, Hoptman, MJ, Kremser, C, Golaszewski, S, Felber, S, Fleischhacker, WW, Delazer, M (2003). Sex differences in brain activation pattern during a visuospatial cognitive task: a functional magnetic resonance imaging study in healthy volunteers. Neuroscience Letters 344, 169172.CrossRefGoogle ScholarPubMed
Woodruff, PW, Wright, IC, Bullmore, ET, Brammer, M, Howard, RJ, Williams, SC, Shapleske, J, Rossell, S, David, AS, McGuire, PK, Murray, RM (1997). Auditory hallucinations and the temporal cortical response to speech in schizophrenia: a functional magnetic resonance imaging study. American Journal of Psychiatry 154, 16761682.CrossRefGoogle ScholarPubMed
Wright, IC, Rabe-Hesketh, S, Woodruff, PW, David, AS, Murray, RM, Bullmore, ET (2000). Meta-analysis of regional brain volumes in schizophrenia. American Journal of Psychiatry 157, 1625.CrossRefGoogle ScholarPubMed