According to the DSM-5, a schizophrenia diagnosis is given if an individual possesses two or more of the following symptoms over the course of a 1-month period: delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior, or negative symptoms. Additionally, at least one of the following three characteristics: delusions, hallucinations, and disorganized speech, must be present. A rapid increase of studies in schizophrenia has covered topics such as abnormal activity in "motor tasks, working memory attention, word fluency, emotion processing, and decision making." Researchers also focus on identifying biomarkers through fMRI scans that could aid early diagnosis. For example, abnormalities in the anterior cingulate cortex and dorsolateral prefrontal cortex are considered potential indicators of schizophrenia risk. In contrast to the abundance of research centered on positive symptoms of the disorder, fMRI research for schizophrenia primarily analyzes the 'failures' of the neural system and the resulting cognitive deficits, with an example being changes in functional connectivity. Another biomarker that can be found through fMRI scans is dysconnectivity within functioning of the cortico-striatal-thalamo-cortical networks. Because this characteristic is associated as an early signal for psychosis, it acts as a marker for predicting a schizophrenia diagnosis. To confirm that a task activates identical regions in schizophrenia patients vs. controls, the given task typically begins easily so that both patients and healthy comparison subjects perform close to 100% accuracy; the task is then increased in difficulty to distinguish activation between two groups with varying abilities of individuals. Eliminating confounding variables by using matched-controlled participants, which match the participant on race, age, sex, occupation...etc. Additionally, increasing datasets of participant groups helps the machine algorithms to improve generalizability across clinical and scanning settings.
The 'disconnectivity hypothesis' is a key theory describing the failure of mechanisms underlying schizophrenia, specifically the failure to integrate information properly. The dysconnectivity hypothesis suggests that disruptions in communication between the brain’s frontal and temporal regions may underlie symptoms like auditory hallucinations and impaired memory, as these areas are critical for integrating sensory input and memory. Functional connectivity, which fMRI evaluates, is the activity coordination between brain regions. It is measured as "temporal correlations of low-frequency oscillations in the BOLD signal between anatomically distinct brain areas" and can reveal resting state networks. The cause for the correlations in fMRI measurements is theorized to be "correlated firing rates of interconnected neurons." Resting-state functional magnetic resonance imaging (rs-fMRI) has become a powerful tool to examine networks' functional connectivity throughout the brain, such as the default mode network (DMN). Through resting-state fMRI, scientists have observed that schizophrenia is associated with altered connectivity patterns in the default mode, central executive, and salience networks. These networks’ dysconnectivity could impact attention, emotion regulation, and self-referential thought processes. Although there are benefits to the resting state fMRI, it is important to note its limitations. fMRI scans measures the blood oxygen level-dependent response (BOLD) when patients partake in specific tasks. Therefore, when a brain region is activated, it takes in more oxygen, which measures and differentiates activity in various neurotransmitter systems. Failure to achieve this causes ambiguity in the areas that are affected, leaving researchers to only see general areas for treatment.
Abnormal brain connectivity has long been theorized as a fundamental cause of psychosis in schizophrenia. rs-fMRI can help evaluate regional interactions at rest and whether there are altered, reduced, or hyperactive connections in psychiatric disorders like schizophrenia. During resting-state fMRI experiments, participants are instructed to relax and stay awake but not think of anything. It is important to note that resting-state networks can change between eyes open and eyes closed conditions. Researchers then measure spontaneous brain activation. There are several advantages to studying the resting state of brain networks — the primary reason is that spontaneous neural activity accounts for most of the brain's activity in contrast to task-based neural activity. Additionally, rs-fMRI eliminates confounding effects such as differing performances between healthy subjects and patients in tasks; rs-fMRI also requires less movement than task-based fMRI studies. Seed-based analysis/ROI approaches to analyzing functional connectivity are common in rs-fMRI for schizophrenia. A seed (region of interest) is first selected, and BOLD time series are then extracted from the seed and all other voxels. After preprocessing, the temporal correlation between the seed and other brain voxels is determined, and the software produces a functional connectivity map. Seed-based comparisons in rs-fMRI have revealed functional disconnectivity in schizophrenia patients in numerous studies, using different ROIs for their seeds — in general, schizophrenia patients show reduced connectivity. Recent studies using resting-state fMRI (rs-fMRI) have identified significant disruptions in functional connectivity across multiple brain networks in schizophrenia, including the default mode, frontotemporal, and cerebellar networks. These findings provide additional support for the dysconnectivity hypothesis, which suggests that impaired coordination between brain regions contributes to the cognitive and behavioral symptoms of schizophrenia. This information is compatible with experiment findings suggesting reduced activation in the amygdala in schizophrenia patients during sadness mood induction, for example.
Morgan, Kevin D.; Dazzan, Paola; Morgan, Craig; Lappin, Julia; Hutchinson, Gerard; Suckling, John; Fearon, Paul; Jones, Peter B.; Leff, Julian; Murray, Robin M.; David, Anthony S. (August 2010). "Insight, grey matter and cognitive function in first-onset psychosis". The British Journal of Psychiatry. 197 (2): 141–148. doi:10.1192/bjp.bp.109.070888. ISSN 0007-1250. PMID 20679268. S2CID 17223664. https://doi.org/10.1192%2Fbjp.bp.109.070888
Algumaei, Ali H.; Algunaid, Rami F.; Rushdi, Muhammad A.; Yassine, Inas A. (2022-05-24). "Feature and decision-level fusion for schizophrenia detection based on resting-state fMRI data". PLOS ONE. 17 (5): e0265300. Bibcode:2022PLoSO..1765300A. doi:10.1371/journal.pone.0265300. ISSN 1932-6203. PMC 9129055. PMID 35609033. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9129055
Voineskos, Aristotle N.; Hawco, Colin; Neufeld, Nicholas H.; Turner, Jessica A.; Ameis, Stephanie H.; Anticevic, Alan; Buchanan, Robert W.; Cadenhead, Kristin; Dazzan, Paola; Dickie, Erin W.; Gallucci, Julia; Lahti, Adrienne C.; Malhotra, Anil K.; Öngür, Dost; Lencz, Todd (February 2024). "Functional magnetic resonance imaging in schizophrenia: current evidence, methodological advances, limitations and future directions". World Psychiatry. 23 (1): 26–51. doi:10.1002/wps.21159. ISSN 1723-8617. PMC 10786022. PMID 38214624. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10786022
Menon, Vinod (October 2011). "Large-scale brain networks and psychopathology: a unifying triple network model". Trends in Cognitive Sciences. 15 (10): 483–506. doi:10.1016/j.tics.2011.08.003. PMID 21908230. https://linkinghub.elsevier.com/retrieve/pii/S1364661311001719
Davis, Justin; Eyre, Harris; Jacka, Felice N; Dodd, Seetal; Dean, Olivia; McEwen, Sarah; Debnath, Monojit; McGrath, John; Maes, Michael; Amminger, Paul; McGorry, Patrick D; Pantelis, Christos; Berk, Michael (2016-06-01). "A review of vulnerability and risks for schizophrenia: Beyond the two hit hypothesis". Neuroscience & Biobehavioral Reviews. 65: 185–194. doi:10.1016/j.neubiorev.2016.03.017. ISSN 0149-7634. PMC 4876729. PMID 27073049. /wiki/Felice_Jacka
Jablensky, Assen (2010-09-30). "The diagnostic concept of schizophrenia: its history, evolution, and future prospects". Dialogues in Clinical Neuroscience. 12 (3): 271–287. doi:10.31887/DCNS.2010.12.3/ajablensky. PMC 3181977. PMID 20954425. https://doi.org/10.31887/DCNS.2010.12.3/ajablensky
Administration, Substance Abuse and Mental Health Services (June 2016). "Table 3.22, DSM-IV to DSM-5 Schizophrenia Comparison". www.ncbi.nlm.nih.gov. Retrieved 2024-11-26. https://www.ncbi.nlm.nih.gov/books/NBK519704/table/ch3.t22/
Gur, Raquel E.; Gur, Ruben C. (2010-09-30). "Functional magnetic resonance imaging in schizophrenia". Dialogues in Clinical Neuroscience. 12 (3): 333–343. doi:10.31887/DCNS.2010.12.3/rgur. PMC 3181978. PMID 20954429. /wiki/Raquel_Gur
Goghari, Vina M.; MacDonald, Angus W. (November 2009). "The neural basis of cognitive control: Response selection and inhibition". Brain and Cognition. 71 (2): 72–83. doi:10.1016/j.bandc.2009.04.004. PMC 2905055. PMID 19427089. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2905055
Voineskos, Aristotle N.; Hawco, Colin; Neufeld, Nicholas H.; Turner, Jessica A.; Ameis, Stephanie H.; Anticevic, Alan; Buchanan, Robert W.; Cadenhead, Kristin; Dazzan, Paola; Dickie, Erin W.; Gallucci, Julia; Lahti, Adrienne C.; Malhotra, Anil K.; Öngür, Dost; Lencz, Todd (February 2024). "Functional magnetic resonance imaging in schizophrenia: current evidence, methodological advances, limitations and future directions". World Psychiatry. 23 (1): 26–51. doi:10.1002/wps.21159. ISSN 1723-8617. PMC 10786022. PMID 38214624. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10786022
Gur, Raquel E.; Gur, Ruben C. (2010-09-30). "Functional magnetic resonance imaging in schizophrenia". Dialogues in Clinical Neuroscience. 12 (3): 333–343. doi:10.31887/DCNS.2010.12.3/rgur. PMC 3181978. PMID 20954429. /wiki/Raquel_Gur
Voineskos, Aristotle N.; Hawco, Colin; Neufeld, Nicholas H.; Turner, Jessica A.; Ameis, Stephanie H.; Anticevic, Alan; Buchanan, Robert W.; Cadenhead, Kristin; Dazzan, Paola; Dickie, Erin W.; Gallucci, Julia; Lahti, Adrienne C.; Malhotra, Anil K.; Öngür, Dost; Lencz, Todd (February 2024). "Functional magnetic resonance imaging in schizophrenia: current evidence, methodological advances, limitations and future directions". World Psychiatry. 23 (1): 26–51. doi:10.1002/wps.21159. ISSN 1723-8617. PMC 10786022. PMID 38214624. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10786022
Gur, Raquel E.; Gur, Ruben C. (2010-09-30). "Functional magnetic resonance imaging in schizophrenia". Dialogues in Clinical Neuroscience. 12 (3): 333–343. doi:10.31887/DCNS.2010.12.3/rgur. PMC 3181978. PMID 20954429. /wiki/Raquel_Gur
Schultze-Lutter, Frauke; Theodoridou, Anastasia (February 2017). "The concept of basic symptoms: its scientific and clinical relevance". World Psychiatry. 16 (1): 104–105. doi:10.1002/wps.20404. PMC 5269478. PMID 28127912. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5269478
Javitt, Daniel C. (2009-04-01). "When Doors of Perception Close: Bottom-up Models of Disrupted Cognition in Schizophrenia". Annual Review of Clinical Psychology. 5 (1): 249–275. doi:10.1146/annurev.clinpsy.032408.153502. ISSN 1548-5943. PMC 4501390. PMID 19327031. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4501390
Schultze-Lutter, Frauke; Theodoridou, Anastasia (26 January 2017). "The concept of basic symptoms: its scientific and clinical relevance". World Psychiatry. 16 (1): 104–105. doi:10.1002/wps.20404. PMC 5269478. PMID 28127912. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5269478
Javitt, Daniel C. (2009-04-01). "When Doors of Perception Close: Bottom-up Models of Disrupted Cognition in Schizophrenia". Annual Review of Clinical Psychology. 5 (1): 249–275. doi:10.1146/annurev.clinpsy.032408.153502. ISSN 1548-5943. PMC 4501390. PMID 19327031. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4501390
Javitt, Daniel C. (2009-04-01). "When Doors of Perception Close: Bottom-up Models of Disrupted Cognition in Schizophrenia". Annual Review of Clinical Psychology. 5 (1): 249–275. doi:10.1146/annurev.clinpsy.032408.153502. ISSN 1548-5943. PMC 4501390. PMID 19327031. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4501390
Green, Michael F.; Horan, William P.; Lee, Junghee (October 2015). "Social cognition in schizophrenia". Nature Reviews Neuroscience. 16 (10): 620–631. doi:10.1038/nrn4005. ISSN 1471-003X. PMID 26373471. https://www.nature.com/articles/nrn4005
Javitt, Daniel C. (2009-04-01). "When Doors of Perception Close: Bottom-up Models of Disrupted Cognition in Schizophrenia". Annual Review of Clinical Psychology. 5 (1): 249–275. doi:10.1146/annurev.clinpsy.032408.153502. ISSN 1548-5943. PMC 4501390. PMID 19327031. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4501390
Rudert, Thomas; Lohmann, Gabriele (December 2008). "Conjunction analysis and propositional logic in fMRI data analysis using Bayesian statistics". Journal of Magnetic Resonance Imaging. 28 (6): 1533–1539. doi:10.1002/jmri.21518. PMID 19025961. S2CID 206097466. https://onlinelibrary.wiley.com/doi/10.1002/jmri.21518
Gomez-Pilar, Javier (30 June 2020). Characterization of neural activity using complex network theory : an application to the study of schizophrenia. Springer. ISBN 978-3-030-49900-6. OCLC 1176541540. 978-3-030-49900-6
Stephan, K. E.; Friston, K. J.; Frith, C. D. (2009-03-30). "Dysconnection in Schizophrenia: From Abnormal Synaptic Plasticity to Failures of Self-monitoring". Schizophrenia Bulletin. 35 (3): 509–527. doi:10.1093/schbul/sbn176. ISSN 0586-7614. PMC 2669579. PMID 19155345. https://academic.oup.com/schizophreniabulletin/article-lookup/doi/10.1093/schbul/sbn176
Li, Peng; Fan, Teng-Teng; Zhao, Rong-Jiang; Han, Ying; Shi, Le; Sun, Hong-Qiang; Chen, Si-Jing; Shi, Jie; Lin, Xiao; Lu, Lin (2017-07-14). "Altered Brain Network Connectivity as a Potential Endophenotype of Schizophrenia". Scientific Reports. 7 (1): 5483. Bibcode:2017NatSR...7.5483L. doi:10.1038/s41598-017-05774-3. ISSN 2045-2322. PMC 5511161. PMID 28710394. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5511161
Wu, Lei; Eichele, Tom; Calhoun, Vince D. (October 2010). "Reactivity of hemodynamic responses and functional connectivity to different states of alpha synchrony: A concurrent EEG-fMRI study". NeuroImage. 52 (4): 1252–1260. doi:10.1016/j.neuroimage.2010.05.053. ISSN 1053-8119. PMC 3059127. PMID 20510374. https://dx.doi.org/10.1016/j.neuroimage.2010.05.053
Schneider, F.; Weiss, U.; Kessler, C.; Salloum, J.B.; Posse, S.; Grodd, W.; Müller-Gärtner, H.W. (November 1998). "Differential amygdala activation in schizophrenia during sadness". Schizophrenia Research. 34 (3): 133–142. doi:10.1016/s0920-9964(98)00085-1. ISSN 0920-9964. PMID 9850979. S2CID 13213002. https://dx.doi.org/10.1016/s0920-9964(98)00085-1
Palaniyappan, Lena; Liddle, Peter F. (2013-04-24). "Diagnostic Discontinuity in Psychosis: A Combined Study of Cortical Gyrification and Functional Connectivity". Schizophrenia Bulletin. 40 (3): 675–684. doi:10.1093/schbul/sbt050. ISSN 1745-1701. PMC 3984507. PMID 23615812. https://academic.oup.com/schizophreniabulletin/article-abstract/40/3/675/1903745?redirectedFrom=fulltext
Voineskos, Aristotle N.; Hawco, Colin; Neufeld, Nicholas H.; Turner, Jessica A.; Ameis, Stephanie H.; Anticevic, Alan; Buchanan, Robert W.; Cadenhead, Kristin; Dazzan, Paola; Dickie, Erin W.; Gallucci, Julia; Lahti, Adrienne C.; Malhotra, Anil K.; Öngür, Dost; Lencz, Todd (February 2024). "Functional magnetic resonance imaging in schizophrenia: current evidence, methodological advances, limitations and future directions". World Psychiatry. 23 (1): 26–51. doi:10.1002/wps.21159. ISSN 1723-8617. PMC 10786022. PMID 38214624. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10786022
Karbasforoushan, H.; Woodward, N.D. (2012-11-01). "Resting-State Networks in Schizophrenia". Current Topics in Medicinal Chemistry. 12 (21): 2404–2414. doi:10.2174/156802612805289863. PMID 23279179. https://www.ingentaconnect.com/content/ben/ctmc/2012/00000012/00000021/art00011;jsessionid=19p46gn37orl.x-ic-live-03
Yu, Qingbao; A. Allen, Elena; Sui, Jing; R. Arbabshirani, Mohammad; Pearlson, Godfrey; D. Calhoun, Vince (2012-11-01). "Brain Connectivity Networks in Schizophrenia Underlying Resting State Functional Magnetic Resonance Imaging". Current Topics in Medicinal Chemistry. 12 (21): 2415–2425. doi:10.2174/156802612805289890. PMC 4429862. PMID 23279180. https://www.ingentaconnect.com/content/ben/ctmc/2012/00000012/00000021/art00012;jsessionid=6k1n1mcqser33.x-ic-live-02
Li, Peng; Fan, Teng-Teng; Zhao, Rong-Jiang; Han, Ying; Shi, Le; Sun, Hong-Qiang; Chen, Si-Jing; Shi, Jie; Lin, Xiao; Lu, Lin (2017-07-14). "Altered Brain Network Connectivity as a Potential Endophenotype of Schizophrenia". Scientific Reports. 7 (1): 5483. Bibcode:2017NatSR...7.5483L. doi:10.1038/s41598-017-05774-3. ISSN 2045-2322. PMC 5511161. PMID 28710394. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5511161
Yu, Qingbao; A. Allen, Elena; Sui, Jing; R. Arbabshirani, Mohammad; Pearlson, Godfrey; D. Calhoun, Vince (2012-11-01). "Brain Connectivity Networks in Schizophrenia Underlying Resting State Functional Magnetic Resonance Imaging". Current Topics in Medicinal Chemistry. 12 (21): 2415–2425. doi:10.2174/156802612805289890. PMC 4429862. PMID 23279180. https://www.ingentaconnect.com/content/ben/ctmc/2012/00000012/00000021/art00012;jsessionid=6k1n1mcqser33.x-ic-live-02
Yu, Qingbao; A. Allen, Elena; Sui, Jing; R. Arbabshirani, Mohammad; Pearlson, Godfrey; D. Calhoun, Vince (2012-11-01). "Brain Connectivity Networks in Schizophrenia Underlying Resting State Functional Magnetic Resonance Imaging". Current Topics in Medicinal Chemistry. 12 (21): 2415–2425. doi:10.2174/156802612805289890. PMC 4429862. PMID 23279180. https://www.ingentaconnect.com/content/ben/ctmc/2012/00000012/00000021/art00012;jsessionid=6k1n1mcqser33.x-ic-live-02
Li, Peng; Fan, Teng-Teng; Zhao, Rong-Jiang; Han, Ying; Shi, Le; Sun, Hong-Qiang; Chen, Si-Jing; Shi, Jie; Lin, Xiao; Lu, Lin (2017-07-14). "Altered Brain Network Connectivity as a Potential Endophenotype of Schizophrenia". Scientific Reports. 7 (1): 5483. Bibcode:2017NatSR...7.5483L. doi:10.1038/s41598-017-05774-3. ISSN 2045-2322. PMC 5511161. PMID 28710394. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5511161
Li, Peng; Fan, Teng-Teng; Zhao, Rong-Jiang; Han, Ying; Shi, Le; Sun, Hong-Qiang; Chen, Si-Jing; Shi, Jie; Lin, Xiao; Lu, Lin (2017-07-14). "Altered Brain Network Connectivity as a Potential Endophenotype of Schizophrenia". Scientific Reports. 7 (1): 5483. Bibcode:2017NatSR...7.5483L. doi:10.1038/s41598-017-05774-3. ISSN 2045-2322. PMC 5511161. PMID 28710394. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5511161
Dabiri, Mona; Dehghani Firouzabadi, Fatemeh; Yang, Kun; Barker, Peter B.; Lee, Roland R.; Yousem, David M. (2022-11-15). "Neuroimaging in schizophrenia: A review article". Frontiers in Neuroscience. 16. doi:10.3389/fnins.2022.1042814. ISSN 1662-453X. PMC 9706110. PMID 36458043. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9706110
Tuovinen, Noora; Hofer, Alex (2023-04-06). "Resting-state functional MRI in treatment-resistant schizophrenia". Frontiers in Neuroimaging. 2. doi:10.3389/fnimg.2023.1127508. ISSN 2813-1193. PMC 10406237. PMID 37554635. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10406237
Barch, Deanna M.; Csernansky, John G. (2007-07-01). "Abnormal Parietal Cortex Activation During Working Memory in Schizophrenia: Verbal Phonological Coding Disturbances Versus Domain-General Executive Dysfunction". American Journal of Psychiatry. 164 (7): 1090–1098. doi:10.1176/ajp.2007.164.7.1090. ISSN 0002-953X. PMID 17606661. https://ajp.psychiatryonline.org/doi/full/10.1176/ajp.2007.164.7.1090