1
|
Lauzon C, Chiasso D, Rabin JS, Ciaramelli E, Rosenbaum RS. Ventromedial Prefrontal Cortex Does Not Play a Selective Role in Pattern Separation. J Cogn Neurosci 2024; 36:435-446. [PMID: 38060255 DOI: 10.1162/jocn_a_02096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Humans have the capacity to form new memories of events that are, at times, highly similar to events experienced in the past, as well as the capacity to integrate and associate new information within existing knowledge structures. The former process relies on mnemonic discrimination and is believed to depend on hippocampal pattern separation, whereas the latter is believed to depend on generalization signals and conceptual categorization supported by the neocortex. Here, we examine whether and how the ventromedial prefrontal cortex (vMPFC) supports discrimination and generalization on a widely used task that was primarily designed to tax hippocampal processes. Ten individuals with lesions to the vMPFC and 46 neurotypical control participants were administered an adapted version of the mnemonic similarity task [Stark, S. M., Yassa, M. A., Lacy, J. W., & Stark, C. E. L. A task to assess behavioral pattern separation (BPS) in humans: Data from healthy aging and mild cognitive impairment. Neuropsychologia, 51, 2442-2449, 2013], which assesses the ability to distinguish previously learned images of everyday objects (targets) from unstudied, highly similar images (lures) and dissimilar images (foils). Relative to controls, vMPFC-lesioned individuals showed intact discrimination of lures from targets but a propensity to mistake studied targets and similar lures for dissimilar foils. This pattern was accompanied by inflated confidence despite low accuracy when responding to similar lures. These findings demonstrate a more general role of the vMPFC in memory retrieval, rather than a specific role in supporting pattern separation.
Collapse
Affiliation(s)
- Claire Lauzon
- Department of Psychology and Centre for Vision Research, York University, Toronto, Canada
- Rotman Research Institute, Toronto, Canada
| | - Daniel Chiasso
- Centre for Studies and Research in Cognitive Neuroscience, University of Bologna, Italy
| | - Jennifer S Rabin
- University of Toronto, Canada
- Harquail Centre for Neuromodulation, Hurvitz Brain Sciences Program, Sunnybrook Research Institute, Toronto, Canada
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Canada
| | - Elisa Ciaramelli
- Centre for Studies and Research in Cognitive Neuroscience, University of Bologna, Italy
- Department of Psychology 'Renzo Canestrari', University of Bologna, Bologna, Italy
| | - R Shayna Rosenbaum
- Department of Psychology and Centre for Vision Research, York University, Toronto, Canada
- Rotman Research Institute, Toronto, Canada
| |
Collapse
|
2
|
Adam-Darque A, Ptak R, Schneider S, Schnider A. Anatomical and functional predictors of disorientation after first-ever brain damage. Neuropsychologia 2023; 187:108601. [PMID: 37263576 DOI: 10.1016/j.neuropsychologia.2023.108601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/20/2023] [Accepted: 05/29/2023] [Indexed: 06/03/2023]
Abstract
BACKGROUND AND OBJECTIVES Disorientation is a frequent consequence of acute brain injury or diffuse disorders, such as confusional states or dementia. Its anatomical correlates are debated. Impaired memory as its commonly assumed mechanism predicts that disorientation is associated with medial temporal damage. The alternative is that disorientation reflects defective orbitofrontal reality filtering (ORFi) - a specific failure to identify whether thoughts or memories refer to present reality or not. The latter is a function of the posterior orbitofrontal cortex and connected structures. This study examined the mechanisms and anatomical basis of disorientation in an unselected group of patients with first-ever subacute brain injury. METHODS Participants hospitalized for neurorehabilitation were asked to participate in this observational cohort study if they had first-ever organic hemispheric brain dysfunction as evident in a localizable brain lesion or verbal amnesia (often without localizable brain damage). Orientation to time, place, situation and person was tested with a 20-items questionnaire. To identify the mechanisms of disorientation, we determined its correlations with executive tasks, verbal episodic memory, and ORFi in all patients. ORFi was examined with a continuous recognition task, which measures learning and item recognition in the first run, and ORFi as reflected in the increase of false positive responses in the second run (temporal context confusion). Lesions of patients having localizable brain damage were manually delineated and normalized before entering multivariate lesion-symptom-mapping (LSM) to determine anatomical predictors of orientation. RESULTS Eighty-four patients (61.1 ± 14.4 years, 29 women) were included. Among measures of memory and executive functioning, a step-wise regression retained temporal context confusion (R = -0.71, p < 0.0001), item recognition (R = 0.67, p < 0.0001) and delayed free recall (R = 0.63, p < 0.0001) as significant predictors of orientation. LSM was possible in 67 participants; it revealed an association of disorientation with damage of the right OFC and the bilateral head of the caudate nucleus. CONCLUSION Disorientation in non-confused, non-demented patients with first-ever brain damage is associated with impaired orbitofrontal reality filtering and memory dysfunction, but not with executive dysfunction. Its main anatomical determinant is damage to the orbitofrontal cortex and its subcortical relay, the head of the caudate.
Collapse
Affiliation(s)
- Alexandra Adam-Darque
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, 1211, Geneva 14, Switzerland
| | - Radek Ptak
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, 1211, Geneva 14, Switzerland
| | - Stephan Schneider
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, 1211, Geneva 14, Switzerland
| | - Armin Schnider
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, 1211, Geneva 14, Switzerland.
| |
Collapse
|
3
|
Colás-Blanco I, Chica AB, Thiebaut de Schotten M, Busquier H, Olivares G, Triviño M. Impaired attention mechanisms in confabulating patients: A VLSM and DWI study. Cortex 2023; 159:175-192. [PMID: 36634529 DOI: 10.1016/j.cortex.2022.09.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/26/2022] [Accepted: 09/13/2022] [Indexed: 12/23/2022]
Abstract
Attention is one of the most studied cognitive functions in brain-damaged populations or neurological syndromes, as its malfunction can be related to deficits in other higher cognitive functions. In the present study, we aimed at delimiting the attention deficits of a sample of brain-injured patients presenting confabulations by assessing their performance on alertness, spatial orienting, and executive control tasks. Confabulating patients, who present false memories or beliefs without intention to deceive, usually show memory deficits and/or executive dysfunction. However, it is also likely that attention processes may be impaired in patients showing confabulations. Here, we compared confabulating patients' attention performance to a lesion control group and a healthy control group. Confabulating patients' mean overall accuracy was lower than the one of healthy and lesion controls along the three experimental tasks. Importantly, confabulators presented a greater Simon congruency effect than both lesion controls and healthy controls in the presence of predictive spatial cues, besides a lower percentage of hits and longer RTs in the Go-NoGo task, demonstrating deficits in executive control. They also showed a higher reliance on alerting and spatially predictive orienting cues in the context of a deficient performance. Grey and white matter analyses showed that patients' percentage of hits in the Go-NoGo task was related to damage to the right inferior frontal gyrus (pars triangularis and pars opercularis), whereas the integrity of the right inferior fronto-occipital fasciculus was negatively correlated with their alertness effect. These results are consistent with previous literature highlighting an executive dysfunction in confabulating patients, and suggest that some additional forms of attention, such as alertness and spatial orienting, could be selectively impaired in this clinical syndrome.
Collapse
Affiliation(s)
- Itsaso Colás-Blanco
- Laboratoire Mémoire, Cerveau et Cognition, Université Paris Cité, Boulogne-Billancourt, Île de France, France; Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, Spain; Department of Experimental Psychology, Faculty of Psychology, University of Granada, Spain.
| | - Ana B Chica
- Mind, Brain, and Behavior Research Center (CIMCYC), University of Granada, Spain; Department of Experimental Psychology, Faculty of Psychology, University of Granada, Spain.
| | - Michel Thiebaut de Schotten
- Brain Connectivity and Behaviour Group, Sorbonne Universities, Paris France; Groupe d'Imagerie Neurofonctionnelle, Institut des Maladies Neurodégénératives-UMR 5293, CNRS, CEA University of Bordeaux, Bordeaux, France
| | - Heriberto Busquier
- Grupo CSUR de epilepsia Refractaria, Servicio de Neurocirugía, Hospital Virgen de Las Nieves, Granada, Spain
| | - Gonzalo Olivares
- Grupo CSUR de epilepsia Refractaria, Servicio de Neurocirugía, Hospital Virgen de Las Nieves, Granada, Spain
| | - Mónica Triviño
- Servicio de Neuropsicología. Hospital Universitario San Rafael, Granada, Spain
| |
Collapse
|
4
|
Habiby Alaoui S, Adam-Darqué A, Ptak R, Schnider A. Distinct outcome processing in deterministic and probabilistic reversal learning. Cortex 2021; 141:224-239. [PMID: 34098424 DOI: 10.1016/j.cortex.2021.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 12/23/2020] [Accepted: 04/21/2021] [Indexed: 11/18/2022]
Abstract
Anticipations that fail to happen are important drivers of behavioral adaptation. Their processing appears to depend on the context. In a deterministic environment, where a stimulus unequivocally predicts the outcome, processing of absent outcomes involves the posterior orbitofrontal cortex (OFC). Failure has been linked to reality confusion with confabulations and disorientation. In a probabilistic environment, absent outcomes appear to be processed by the anterior cingulate cortex (ACC) rather than the OFC. Failure has been associated with poor decision making and schizophrenia. These data suggest different mechanisms depending on the context. Here, healthy human subjects made two formally similar reversal learning tasks, but one with deterministic, the other with probabilistic instructions. Brain activity was monitored using high-density electroencephalography. We found that in the deterministic task, negative outcomes, which unequivocally call for a behavioral switch, induced a distinct frontal potential at 200-300 msec. Computational modeling indicated a strong association of evoked potentials with prediction error, surprise, and behavioral adaptation. In the probabilistic task, where behavioral adaptation follows the cumulated processing of outcomes, negative outcomes evoked potentials that were associated with prediction error and surprise, but had a weak link with subsequent behavior. Outcome processing in the probabilistic task induced stronger activation than the deterministic task of an extended network including the ACC, OFC and striatum at 300-400 msec. In both tasks, negative outcomes were processed differently from positive outcomes at 400-600 msec, possibly reflecting updating of the outcome record. We conclude that the brain disposes of at least two distinct systems processing outcomes with unequivocal or ambiguous behavioral significance. These systems differ along behavioral, clinical, electrophysiological and anatomical dimensions.
Collapse
Affiliation(s)
- Selim Habiby Alaoui
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University of Geneva, Switzerland
| | - Alexandra Adam-Darqué
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University of Geneva, Switzerland
| | - Radek Ptak
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University of Geneva, Switzerland; Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital of Geneva, Switzerland
| | - Armin Schnider
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University of Geneva, Switzerland; Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital of Geneva, Switzerland.
| |
Collapse
|
5
|
Abstract
Patients with Alzheimer's Disease (AD) not only are suffering from amnesia but also are prone to memory distortions, such as experiencing detailed and vivid recollections of episodic events that have never been encountered (i.e., false memories). To describe and explain these distortions, we offer a review to synthesize current knowledge on false memory in AD into a framework allowing for better understanding of the taxonomy and phenomenology of false memories and of the cognitive mechanisms that may underlie false memory formation in AD. According to this review, certain phenomenological characteristics of memories (e.g., high emotional load, high vividness, or high familiarity) result in misattributions in AD. More specifically, this review proposes that generalized decline in cognitive control and inhibition in AD may result in difficulties in suppressing irrelevant information during memory monitoring, especially when irrelevant (i.e., false) information is characterized by high emotion, vividness, or familiarity. This review also proposes that binding deficits in AD decrease the ability to retrieve relevant contextual details, leading to source monitoring errors and false memories. In short, this review depicts how phenomenological characteristics of memories and failures of monitoring during retrieval contribute to the occurrence of false memory in AD.
Collapse
|
6
|
Frontolimbic affective bias and false narratives from brain disease. Med Hypotheses 2019; 128:13-16. [PMID: 31203901 DOI: 10.1016/j.mehy.2019.04.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 04/28/2019] [Indexed: 11/23/2022]
Abstract
Since the nineteenth century, clinicians and investigators have systematically evaluated the origin of delusions and psychotic thinking. One major clue to understanding the neurobiological underpinnings of delusions is the emergence of false narratives from brain disease. In addition to delusions themselves, there are a range of other false narratives not due to deliberate lying and resulting from neurological disorders, including provoked confabulations, fantastic confabulations, false memories, magical thinking, dream delusions, and "fantastic thinking". A comparison of their characteristics, similarities, and differences suggest a hypothesis: despite different sources for their false narrative experiences, such as unusual thoughts or perceptions, all false narratives from brain disease involve erroneous or mismatched "affective biases" applied to the experiences. Affective labels usually signal the sense of rightness, sense of familiarity, and the external vs. internal origin of an experience, and they can be altered by limbic neuropathology. The location and involvement of neuropathology that facilitates false narratives involves frontolimbic regions and their connections, particularly on the right. Future investigations can focus on frontolimbic mechanisms involved in the provision of the intrinsically-linked affective biases, which indicate the nature and external/internal origin of experiences.
Collapse
|
7
|
Abstract
OBJECTIVES To investigate a possible confabulation resilience of the developing brain. METHODS We performed a literature search on confabulation in PubMed and identified all empirical studies of children and adolescents under the age of 18. RESULTS The analysis identified only three case studies of confabulation in children under the age of 18 of 286 empirical studies of confabulation. This reveals a striking discrepancy in the number of reported cases caused by brain injury between children and adults. We hypothesize that there may be a resilience toward confabulation in the developing brain and present three tentative explanations regarding the possible underlying mechanisms. CONCLUSIONS Additional awareness on the scarcity of reported cases of confabulation in children could lead to important insights on the nature of confabulation and greater understanding of the resilience and plasticity of the developing brain. (JINS, 2019, 25, 426-431).
Collapse
|
8
|
Thézé R, Manuel AL, Pedrazzini E, Chantraine F, Patru MC, Nahum L, Guggisberg AG, Schnider A. Neural correlates of reality filtering in schizophrenia spectrum disorder. Schizophr Res 2019; 204:214-221. [PMID: 30057100 DOI: 10.1016/j.schres.2018.07.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 05/11/2018] [Accepted: 07/22/2018] [Indexed: 01/28/2023]
Abstract
BACKGROUND A false sense of reality is a characteristic of schizophrenia spectrum disorders (SSD). Reality confusion may also emanate from posterior orbitofrontal cortex (OFC) lesions, as evident in confabulations that patients act upon and disorientation. This confusion can be measured by repeated runs of a continuous recognition task (CRT): patients increase their false positive rate from the second run on, failing to realize that an item is not a repetition within the current run. Correct handling of these stimuli, a faculty called orbitofrontal reality filtering (ORFi), induces a distinct frontal potential at 200-300 ms, the "ORFi potential". Patients with schizophrenia have been reported to fail in this task, too. Here, we explored the electrophysiology of ORFi in SSD. METHODS Evoked potentials, source, and connectivity analyses derived from high-density electroencephalograms of 17 patients with SSD and 15 age-matched healthy controls performing two runs of a CRT. RESULTS Although the patients obtained normal performance, they did not normally express the frontal potential typical of ORFi between 200 and 300 ms. Coherence analysis demonstrated virtually absent functional connectivity in the theta band within the memory network in this period. Source analysis showed increased activity in left medial temporal and prefrontal regions in patients. CONCLUSIONS SSD patients appear to invoke compensatory resources to handle the challenges of reality filtering. An abnormal ORFi potential may be an early biomarker of SSD.
Collapse
Affiliation(s)
- Raphaël Thézé
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| | - Aurélie L Manuel
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| | - Elena Pedrazzini
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| | - Fabrice Chantraine
- Department of Mental Health and Psychiatry, University Hospital of Geneva, Switzerland
| | - Maria Cristina Patru
- Department of Mental Health and Psychiatry, University Hospital of Geneva, Switzerland
| | - Louis Nahum
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| | - Adrian G Guggisberg
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| | - Armin Schnider
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland.
| |
Collapse
|
9
|
Thézé R, Manuel AL, Nahum L, Guggisberg AG, Schnider A. Simultaneous Reality Filtering and Encoding of Thoughts: The Substrate for Distinguishing between Memories of Real Events and Imaginations? Front Behav Neurosci 2017; 11:216. [PMID: 29163088 PMCID: PMC5671946 DOI: 10.3389/fnbeh.2017.00216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 10/18/2017] [Indexed: 11/13/2022] Open
Abstract
Any thought, whether it refers to the present moment or reflects an imagination, is again encoded as a new memory trace. Orbitofrontal reality filtering (ORFi) denotes an on-line mechanism which verifies whether upcoming thoughts relate to ongoing reality or not. Its failure induces reality confusion with confabulations and disorientation. If the result of this process were simultaneously encoded, it would easily explain later distinction between memories relating to a past reality and memories relating to imagination, a faculty called reality monitoring. How the brain makes this distinction is unknown but much research suggests that it depends on processes active when information is encoded. Here we explored the precise timing between ORFi and encoding as well as interactions between the involved brain structures. We used high-density evoked potentials and two runs of a continuous recognition task (CRT) combining the challenges of ORFi and encoding. ORFi was measured by the ability to realize that stimuli appearing in the second run had not appeared in this run yet. Encoding was measured with immediately repeated stimuli, which has been previously shown to induce a signal emanating from the medial temporal lobe (MTL), which has a protective effect on the memory trace. We found that encoding, as measured with this task, sets in at about 210 ms after stimulus presentation, 35 ms before ORFi. Both processes end at about 330 ms. Both were characterized by increased coherence in the theta band in the MTL during encoding and in the orbitofrontal cortex (OFC) during ORFi. The study suggests a complex interaction between OFC and MTL allowing for thoughts to be re-encoded while they undergo ORFi. The combined influence of these two processes at 200-300 ms may leave a memory trace that allows for later effortless reality monitoring in most everyday situations.
Collapse
Affiliation(s)
- Raphaël Thézé
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| | - Aurélie L Manuel
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| | - Louis Nahum
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| | - Adrian G Guggisberg
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| | - Armin Schnider
- Laboratory of Cognitive Neurorehabilitation, Division of Neurorehabilitation, Department of Clinical Neurosciences, University Hospital and University of Geneva, Geneva, Switzerland
| |
Collapse
|
10
|
Ventromedial prefrontal cortex generates pre-stimulus theta coherence desynchronization: A schema instantiation hypothesis. Cortex 2017; 87:16-30. [DOI: 10.1016/j.cortex.2016.10.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 08/28/2016] [Accepted: 10/11/2016] [Indexed: 11/18/2022]
|