Angelica Staniloiu

Memory, autonoetic consciousness, and the self ☆

Memory is a general attribute of living species, whose diversification reflects both evolutionary and developmental processes. Episodic-autobiographical memory (EAM) is regarded as the highest human ontogenetic achievement and as probably being uniquely human. EAM, autonoetic consciousness and the self are intimately linked, grounding, supporting and enriching each others development and cohesiveness. Their development is influenced by the socio-cultural-linguistic environment in which an individual grows up or lives. On the other hand, through language, textualization and social exchange, all three elements leak into the world and participate to the dynamic shaping and re-shaping of the cultural scaffolding of the self, mental time traveling and EAM formation. Deficits in self-related processing, autonetic consciousness, emotional processing and mental time traveling can all lead to or co-occur with EAM disturbances, as we illustrate by findings from EAM impairments associated with neurological or psychiatric disorders.

Amygdala in action: Relaying biological and social significance to autobiographical memory

The human amygdala is strongly embedded in numerous other structures of the limbic system, but is also a hub for a multitude of other brain regions it is connected with. Its major involvement in various kinds of integrative sensory and emotional functions makes it a cornerstone for self-relevant biological and social appraisals of the environment and consequently also for the processing of autobiographical events. Given its contribution to the integration of emotion, perception and cognition (including memory for past autobiographical events) the amygdala also forges the establishment and maintenance of an integrated self. Damage or disturbances of amygdalar connectivity may therefore lead to disconnection syndromes, in which the synchronous processing of affective and cognitive aspects of memory is impaired. We will provide support for this thesis by reviewing data from patients with a rare experiment of nature - Urbach-Wiethe disease - as well as other conditions associated with amygdala abnormalities. With respect to memory processing, we propose that the amygdalas role is to charge cues so that mnemonic events of a specific emotional significance can be successfully searched within the appropriate neural nets and re-activated.

The impairment of recollection in functional amnesic states

INTRODUCTION Functional amnesia refers to various forms of amnesia, which have no direct organic brain basis. Psychological stress and trauma were etiologically linked to its development across various cultures. METHODS We have studied several patients with functional amnesia, employing neuropsychological and neuroimaging methods. Herein we provide a review of the current understanding of the phenomenology, neuropsychology and neurobiology of functional amnesia, which we illustrate by reference to five own case descriptions and other cases presented in the literature. RESULTS Functional amnesia is mostly of retrograde nature and presents in the form of a memory blockade or repression to recollect episodic-autobiographical events, which may cover the whole past life. Sometimes, the recollection impairment is localized to certain time epochs. In comparison to functional retrograde amnesia, functional isolated anterograde amnesia is much rarer and data on its neurobiology are scant. In patients with functional amnesia with pronounced retrograde episodic-autobiographical memory impairments, we identified changes in brain metabolism, above all reductions in the temporo-frontal regions of the right hemisphere. Recently, even subtle structural changes in the white matter of the (right) frontal cortex were described in functional retrograde amnesia by other researchers. CONCLUSIONS The disruption in recollection in functional amnesia is often accompanied by changes in personality dimensions, pertaining to cognition (self-related processing, theory of mind), autonoetic consciousness and affectivity. This suggests that functional amnesia is a multifaceted condition. We hypothesize that the recollection deficit in functional retrograde amnesia primarily reflects a desynchronization between a frontal lobe system, important for autonoetic consciousness, and a temporo-amygdalar system, important for evaluation and emotions. Despite assumptions that functional amnesia can always be reversed, several cases of functional amnesia were found to follow a chronic course, suggesting a need for longitudinal prospective studies to quantify possible global cognitive deterioration over time and its neural underpinnings.

Ganser syndrome with work-related onset in a patient with a background of immigration

Introduction. A substantial proportion of the recently published cases of dissociative disorders have a background of immigration (Fujiwara et al., 2008). Among the dissociative disorders, Ganser syndrome is an uncommon form that has as central symptom the giving of approximate answers to questions (vorbeireden). The predisposing and triggering factors of Ganser syndrome are poorly defined. Furthermore, this condition might cooccur with other psychiatric disorders. Here we describe a patient with a background of immigration, who, after an objectively minor work-related head injury, developed severe and persistent psychiatric symptoms, with features of Ganser syndrome. Methods. The patient was assessed medically, psychiatrically, and by neuropsychological testing. Results. The patient is a man with no known previous psychiatric history, who lived in several countries and encountered a series of stressful experiences in the process of migration. Several years after immigrating to his current country of residency, he developed severe psychiatric symptoms of Major Depressive Disorder, with Psychotic Features and Ganser syndrome. The symptoms, which emerged after a mild head injury, have persisted for more than a year, despite treatment. Conclusions. The similarity between this case and other reports suggests that psychosocial stresses accompanying immigration may have a catalytic effect in triggering and maintaining dissociative symptomatology.

Towards solving the riddle of forgetting in functional amnesia: recent advances and current opinions

Remembering the past is a core feature of human beings, enabling them to maintain a sense of wholeness and identity and preparing them for the demands of the future. Forgetting operates in a dynamic neural connection with remembering, allowing the elimination of unnecessary or irrelevant information overload and decreasing interference. Stress and traumatic experiences could affect this connection, resulting in memory disturbances, such as functional amnesia. An overview of clinical, epidemiological, neuropsychological, and neurobiological aspects of functional amnesia is presented, by preponderantly resorting to own data from patients with functional amnesia. Patients were investigated medically, neuropsychologically, and neuroradiologically. A detailed report of a new case is included to illustrate the challenges posed by making an accurate differential diagnosis of functional amnesia, a condition that may encroach on the boundaries between psychiatry and neurology. Several mechanisms may play a role in “forgetting” in functional amnesia, such as retrieval impairments, consolidating defects, motivated forgetting, deficits in binding and reassembling details of the past, deficits in establishing a first person autonoetic connection with personal events, and loss of information. In a substantial number of patients, we observed a synchronization abnormality between a frontal lobe system, important for autonoetic consciousness, and a temporo-amygdalar system, important for evaluation and emotions, which provides empirical support for an underlying mechanism of dissociation (a failure of integration between cognition and emotion). This observation suggests a mnestic blockade in functional amnesia that is triggered by psychological or environmental stress and is underpinned by a stress hormone mediated synchronization abnormality during retrieval between processing of affect-laden events and fact-processing.

Social cognition in a case of amnesia with neurodevelopmental mechanisms

Episodic–autobiographical memory (EAM) is considered to emerge gradually in concert with the development of other cognitive abilities (such as executive functions, personal semantic knowledge, emotional knowledge, theory of mind (ToM) functions, language, and working memory). On the brain level its emergence is accompanied by structural and functional reorganization of different components of the so-called EAM network. This network includes the hippocampal formation, which is viewed as being vital for the acquisition of memories of personal events for long-term storage. Developmental studies have emphasized socio-cultural-linguistic mechanisms that may be unique to the development of EAM. Furthermore it was hypothesized that one of the main functions of EAM is the social one. In the research field, the link between EAM and social cognition remains however debated. Herein we aim to bring new insights into the relation between EAM and social information processing (including social cognition) by describing a young adult patient with amnesia with neurodevelopmental mechanisms due to perinatal complications accompanied by hypoxia. The patient was investigated medically, psychiatrically, and with neuropsychological and neuroimaging methods. Structural high resolution magnetic resonance imaging revealed significant bilateral hippocampal atrophy as well as indices for degeneration in the amygdalae, basal ganglia, and thalamus, when a less conservative threshold was applied. In addition to extensive memory investigations and testing other (non-social) cognitive functions, we employed a broad range of tests that assessed social information processing (social perception, social cognition, social regulation). Our results point to both preserved (empathy, core ToM functions, visual affect selection, and discrimination, affective prosody discrimination) and impaired domains of social information processing (incongruent affective prosody processing, complex social judgments). They support proposals for a role of the hippocampal formation in processing more complex social information that likely requires multimodal relational handling.

Neuroscience, neuroimaging and the law

Violence is a phenomenon we are daily confronted with in the media and everyday life. Yearly more than one and a half million of humans are reported to lose their lives due to violence. Violence has links to aggression, an almost universal phenomenon in animal kingdom that may in some instances serve the purpose of survival of species (e.g., the maternal aggression for defending offspring). Violence is classified according to target and mode. Our focus here is on the individual violent behavior toward others and contributions from neuroimaging to understanding its putative neurobiological underpinnings and reframing the “nature-nurture” debate. Historical tracing of the nature-nurture discussion concerned with the etiology of individual violent and criminal behavior reveals back and forth shifts from biological to environmental determinism. At one pole of the dialectics, we find incisive arguments for an incorrigible biological determinism, at the other, an embracement of a naı̈ve environmental causality (Heide and Solomon, 2006; Caspi et al., 2010). Despite persistence of terminologies such as “genes of violence” or “born to be criminal” in both scientific literature and media, a careful review of recent advances in neuroscience, genetics, epigenetics and neuroimaging nowadays paints a more nuanced and complex picture of the current neuroscientific understanding of the underpinnings of the individual violent behavior. Individual violent behavior can be viewed as a complex behavior that arises from a dynamic and likely time-sensitive interplay between genes and environment (including personal and cultural environment). Advances in the epigenetic field have taught us that genes (nature) and environment (nurture) cannot anymore be seen as separate, additive entities. Instead environmental factors can influence gene expression and brain development and synaptic plasticity in a time-dependent fashion. This suggests a role for time-sensitive environmental manipulations and opens a pathway of hope for designing violence prevention strategies.

Retrieval, Monitoring, and Control Processes: A 7 Tesla fMRI Approach to Memory Accuracy

Memory research has been guided by two powerful metaphors: the storehouse (computer) and the correspondence metaphor. The latter emphasizes the dependability of retrieved mnemonic information and draws upon ideas about the state dependency and reconstructive character of episodic memory. We used a new movie to unveil the neural correlates connected with retrieval, monitoring, and control processes, and memory accuracy (MAC), according to the paradigm of Koriat and Goldsmith (1996a,b). During functional magnetic resonance imaging, subjects performed a memory task which required (after an initial learning phase) rating true and false statements [retrieval phase (RP)], making confidence judgments in the respective statement [monitoring phase (MP)], and deciding for either venturing (volunteering) the respective answer or withholding the response [control phase (CP)]. Imaging data pointed to common and unique neural correlates. Activations in brain regions related to RP and MAC were observed in the precuneus, middle temporal gyrus, and left hippocampus. MP was associated with activation in the left anterior and posterior cingulate cortex along with bilateral medial temporal regions. If an answer was volunteered (as opposed to being withheld) during the CP, temporal, and frontal as well as middle and posterior cingulate areas and the precuneus revealed activations. Increased bilateral hippocampal activity was found during withholding compared to volunteering answers. The left caudate activation detected during withholding compared to venturing an answer supports the involvement of the left caudate in inhibiting unwanted responses. Contrary to expectations, we did not evidence prefrontal activations during withholding (as opposed to volunteering) answers. This may reflect our design specifications, but alternative interpretations are put forth.

Dissociation, Memory and Trauma Narrative

Memory has interested both scientific researchers and writers for centuries. The ability to remember things from the past has been viewed not only as a cornerstone for an individual‘s consistent feeling of trans-temporal identity (at least in highly industrialized and individualized countries), but also for preserving a group’s identity and values. (»Je me souviens« – I remember – is the official motto of the province Quebec of Canada). While some authors perceive the ability to memorize and recall things as a high virtue, others emphasize that an important ingredient of the well-being of an individual is the optimal balance between remembering and forgetting (Luria 1987; Hacking 1995). In Greek mythology, drinking from the river Lethe leads to forgetfulness, a potential ailment for traumatic experiences. In other mythologies or stories the same happens if people enter valleys or plains of Forgetfulness. New research attempts nowadays to discover drugs that can soothe people who suffer from recurrent disturbing traumatic memories, by weakening their memories via interfering with their consolidation or post-retrieval consolidation (Brunet et al. 2008). People have been aware for a long time that memory in fact is not reliable, but may be subject to various distortions and biases (K hnel/Markowitsch 2009). Each act of remembering may be viewed in a way as an act of re-transcription (›Nachtr glichkeit‹), re-categorization and to some degree imagination (Modell 2006). Various forms of illnesses accompanied by memory impairments are described in neurology and psychiatry; all of them demonstrate in how many ways remembrances and newly encoded events are modulated and changed by different own previous remembrances as well as by environmental influences. Sigmund Freud was among the most prominent writers on memory distortions, subconscious forms of remembering and trauma-related memory problems (Breuer/ Freud 1895). Freud’s work also constitutes a good example on how memory is influenced by cultural context and various forms of illnesses, especially psychic ones (Freud 1898; 1899; 1901a; 1901b; 1910; 1921). His case studies of trauma might in fact be seen as precursors of a literature that imposed itself after the second World War and was substantially inspired by the Holocaust experiences – the

Neuroimaging and Dissociative Disorders

Although they were for a while “dissociated” (Spiegel, 2006) from the clinical and scientific arena, dissociative disorders have in the last several years received a renewed interest among several groups of researchers, who embarked on the work of identifying and describing their underlying neural correlates. Dissociative disorders are characterized by transient or chronic failures or disruptions of integration of otherwise integrated functions of consciousness, memory, perception, identity or emotion. The DSM-IV-TR (2000) includes nowadays under the heading of dissociative disorders several diagnostic entities, such as dissociative amnesia and fugue, depersonalization disorder, dissociative identity disorder and dissociative disorder not otherwise specified (such as Ganser syndrome). In contrast to DSM-IV-TR, ICD-10 (1992) also comprises under the category of dissociative (conversion) disorder the entity of conversion disorder (with its various forms), which is in DSM-IV-TR (2000) captured under the heading of somatoform disorders (and probably will remain under the same heading in the upcoming DSM-V).