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Studying memory in infants can be challenging, as they cannot express their subjective recollection verbally. In this study we use a novel method with which we can assess episodic recognition memory through pupillometry, using identical procedures and stimuli for infants and adults. In three experiments of 4-and 7-month- old infants, and adults we show that the adult pupillary response is larger to previously seen than to never seen items (old/new effect). Pupil dilations index subjective memory experience in adults, producing distinct pupil dilations to items judged as remembered, familiar, and new, regardless of actual previous exposure (Experiment 1). Seven-month- old infants demonstrate a clear pupillary old/new effect, very similar to that of adults (Experiment 2), whereas 4-month- olds do not demonstrate such an effect (Experiment 3). Our findings suggest that the mnemonic mechanisms that serve infants’ and adults’ episodic recognition memory are more similar than previously asserted: they are not fully developed at 4 months of age but that there is contiguity in human episodic memory development from 7 months of age. [ABSTRACT FROM AUTHOR]

While there is ample evidence that the hippocampus is functionally heterogeneous along its longitudinal axis, there is still no consensus regarding its exact organization. Whereas spatial memory tasks frequently engage the posterior hippocampus, the regions engaged during episodic memory are more varying and may depend on the specific nature of the stimuli. Here, we investigate the effect of stimulus content on the location of hippocampal recruitment during episodic memory encoding and retrieval of pictorial and verbal material with a meta-analysis approach, using activation likelihood estimation and restricting the analysis to the hippocampus. Verbal material was associated with left-lateralized anterior activation, compared to pictorial material that recruited a more posterior aspect of the hippocampus, primarily within the right hemisphere. This effect held for encoding of both single items and item-item associations but was less clear during retrieval. The findings lend further support to a functional subdivision of the hippocampus along its longitudinal axis and indicate that the content of episodic memories is one factor that determines the location of hippocampal recruitment. [ABSTRACT FROM AUTHOR]

Autobiographical memory in major depression has been characterized as overgeneralized, with patients recalling few episodic details, prioritizing general schematic events. However, whether this effect reflects impaired episodic or semantic memory, or domain-general cognitive processes, is unknown. We used the Autobiographical Interview (Levine, Svoboda, Hay, Winocur, & Moscovitch, 2002) to derive episodic and semantic contributions to autobiographical memory in patients with severe major depression. We also assessed memory for public events and famous people. Depressed patients were impaired on episodic, but not semantic, autobiographical memory from 2 weeks to 10 years before testing. They were also impaired on memory for public events, possibly because they followed the news less than controls. Patients' memory for famous names was not impaired, although this was strongly associated with non-episodic memories to a greater degree than in controls. The findings suggest a specific impairment of episodic autobiographical memory in depression that is not fully accounted for by domain-general processes involved in strategic retrieval. [ABSTRACT FROM AUTHOR]

The hippocampus is crucial for episodic autobiographical memory retrieval. Functional neuroimaging evidence suggests that it is similarly engaged in recent and remote retrieval when memories are matched on vividness and personal importance. Far fewer studies have investigated the nature of hippocampal-neocortical coactivation in relation to memory remoteness. The purpose of this study was to examine hippocampal activity and functional connectivity as a function of memory age. Unlike most studies of autobiographical memory, we included autobiographical memories formed in the days and weeks before scanning, in addition to truly remote memories on the order of months and years. Like previous studies, we found that the hippocampus was active bilaterally regardless of memory age, with anterior activity increasing up to 1 yr and then decreasing, and with posterior activity being less sensitive to memory age. More importantly, hippocampal functional connectivity varied with memory age. Retrieving recent memories (≤1 yr) showed a late coactivation of the hippocampus and areas of the autobiographical memory network, whereas retrieving remote memories (10 yrs) showed an early negative coactivation of the hippocampus and left inferior frontal gyrus followed by a positive coactivation with anterior cingulate. This finding may reflect that the hippocampus is more strongly integrated with the autobiographical memory network for recent than for remote memories, and that more effort is required to recover remote memories. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: It has been unclear to what extent memory is affected in frontotemporal lobar degeneration (FTLD). Since patients usually have atrophy in regions implicated in memory function, the frontal and/or temporal lobes, one would expect some memory impairment, and that the degree of atrophy in these regions would be inversely related to memory function. The purposes of this study were (1) to assess episodic memory function in FTLD, and more specifically patients’ ability to episodically re-experience an event, and determine its source; (2) to examine whether memory performance is related to quantified regional brain atrophy. FTLD patients (n =18) and healthy comparison subjects (n =14) were assessed with cued recall, recognition, “remember/know” (self-reported re-experiencing) and source recall, at 30min and 24h after encoding. Regional gray matter volumes were assessed with high resolution structural MRI concurrently to testing. Patients performed worse than comparison subjects on all memory measures. Gray matter volume in the left medial temporal lobe was positively correlated with recognition, re-experiencing, and source recall. Gray matter volume in the left posterior temporal lobe correlated significantly with recognition, at 30min and 24h, and with source recall at 30min. Estimated familiarity at 30min was positively correlated with gray matter volume in the left inferior parietal lobe. In summary, episodic memory deficits in FTLD may be more common than previously thought, particularly in patients with left medial and posterior temporal atrophy. [Copyright &y& Elsevier]

Abstract: Although it is well established that alcohol impairs episodic memory encoding, it is unknown how this occurs on a cerebral level. We scanned intoxicated and sober individuals with functional magnetic resonance imaging (fMRI) while they encoded various materials that were recalled the following day. Alcohol impaired memory for object pairs and face–name pairs, but not for words and phrase–word pairs. Impaired performance was associated with reduced bilateral prefrontal activation and non-specific activation of the parahippocampal gyrus. These results suggest that alcohol impairs episodic memory by interfering with activity of regions involved in encoding, and further indicate which regions are critical for human memory. [Copyright &y& Elsevier]

Abstract: The aging, non-demented brain undergoes several physiological changes, some of which may affect cognitive function. The goal of the present study was to examine the associations between subcortical and periventricular white matter hyperintensities (WMHs), cortical and subcortical atrophy, and cognitive function (episodic memory, word fluency, attention, and perceptual, cognitive, and motor speed). This was done within a European collaborative study, Cardiovascular Determinants of Dementia (CASCADE), in which magnetic resonance imaging (MRI) was performed on community-dwelling individuals. The study includes 1254 persons from eight European study centers, ranging between 64 and 76 years of age (M 69.4±3.3; 55% men). When demographics (age, education, and sex), study center, and concurrent brain changes had been adjusted for, periventricular WMHS predicted lower performance in word fluency and the Stroop test (time), and subcortical atrophy predicted lower performance in motor speed and the Stroop test (errors). The findings are consistent with findings from lesion and functional neuroimaging studies. [Copyright &y& Elsevier]

Since the second part of the 19th century, there has been a great increase in the number of international scientific congresses, and they appear a necessary step in the maturation of knowledge. The first person to explicitly suggest the necessity of an international congress of psychology was Julian Ochorowicz (1850–1917), who was considered the founder of Polish psychology. In 1881 he sent an article to Théodule Ribot, editor of Revue Philosophique de la France et de l'Étranger , entitled “Project of an International Congress of Psychology,” which was published in Ribot's journal. In it he described the dispersed state of psychology in 1881 and the previous 50 years, including 12 subdisciplines ranging from psychophysics to the psychology of art, and how it should aim for unification. He suggested collective efforts to progress rapidly, with widespread collaboration and the continuous exchange of observations, information, and experiments. Having international congresses would constitute a forum for such exchanges, and in his article he outlined the steps that should be taken for putting together the first international congress of psychology. The proposal was quite extensive and fanciful, making Ribot somewhat doubt its realizability. Nevertheless, the first international psychology congress took place in Paris in 1889, 8 years after the publication of Ochorowicz's article. This quick development could be attributed to the creation of the psychology societies, one of the first being La Société de Psychologie Physiologique , which was created in France in 1885. The creation of this society also contributed to psychology being recognized as a scientific domain. In line with this, the final programme of the congress was less extensive than that proposed in Ochorowicz's article, focusing on physiological aspects and ignoring the philosophical ones. In the present paper, the historical context of Ochorowicz's article is outlined, followed by a translation of his article. Au cours de la seconde moitié du XIXe siècle, les congrès scientifiques internationaux se sont multipliés; ils apparaissaient comme une étape nécessaire dans la maturation du savoir. La première personne qui a explicitement proposé la nécessité d'un congrès international de psychologie fut Julian Ochorowicz (1850–1917), considéré comme le fondateur de la psychologie polonaise. En 1881, il envoie un article à Théodule Ribot, directeur de la « Revue philosophique de la France et de l'étranger », ayant pour titre « Projet d'un congrès international de psychologie » qui fut publié dans le journal de Ribot. Dans l'article, il décrit la psychologie en 1881 et son état de dispersion depuis une cinquantaine d'années, comprenant 12 sous‐disciplines allant de la psychophysique à la psychologie de l'art, et propose des solutions pour son unification. Il suggère une prise de conscience collective pour avancer rapidement, avec des collaborations et des échanges continus d'observations, d'informations et d'expériences. Les congrès internationaux constitueraient un forum pour ce genre d'échanges. De plus, dans l'article, il décrit les étapes nécessaires pour mettre en place le premier congrès international de psychologie. La proposition était très large et un peu utopique, ce qui a rendu Ribot un peu sceptique sur la possibilité de réaliser une telle manifestation. Néanmoins, le premier congrès international de psychologie se tint à Paris en 1889, 8 ans après la publication de l'article d'Ochorowicz. Ce développement rapide peut certainement être attribué à la création des sociétés de psychologie. Une des premières d'entre elles, la Société de psychologie physiologique, fut créée en France en 1885. La création de cette société contribua aussi à ce que la psychologie soit reconnue dans le domaine scientifique. En lien avec cela, le programme final du congrès fut plus restrictif que celui proposé dans l'article d'Ochorowicz puisqu'il fut centré sur les aspects physiologiques de la psychologie en laissant de côté les aspects philosophiques. Cet article contient la traduction du texte d'Ochorowicz et est précédé par une description du contexte historique de sa publication. Desde la segunda mitad del siglo 19, el número de congresos internacionales científicos ha aumento, lo que parece un paso necesario para la maduración del conocimiento. La primera persona que sugirió explícitamente la necesidad de un congreso de psicología fue Julian Ochorowicz (1850–1917), considerado el fundador de la psicología polaca. En 1881 envió un artículo a Théodule Ribot, editor del Revue Philosophique de la France et de l'Étranger , titulado ‘Project of an International Congress of Psychology’ que Ribot publicó en su revista. En él describía el estado disperso de la psicología en 1881 y los 50 años previos, lo que incluye doce subdisciplinas que abarcan de la psicofísica a la psicología del arte, y cómo debe aspirar a la unificación. Él sugirió el esfuerzo colectivo para progresar rápidamente, con la colaboración amplia y el intercambio continuo de observaciones, información y experimentos. El congreso constituiría un foro para tales intercambios, y en este artículo delineó los pasos que debían seguirse para organizar el primer congreso internacional de psicología. La propuesta era extensa y ambiciosa, lo que hizo dudar a Ribot de su viabilidad. No obstante, el primer congreso internacional de psicología se llevó a cabo en París en 1889, ocho años después de la publicación del artículo de Ochorowicz. Este rápido desarrollo podría atribuirse a la creación de las sociedades científicas, de las cuales una de las primeras fue La Société de Psychologie Physiologique creada en Francia en 1885. La creación de esta sociedad también contribuyó a la psicología al reconocerse como un dominio científico. Dentro de este contexto, el programa final del congreso fue menos extenso que el propuesto en el artículo de Ochorowicz, al concentrarse en los aspectos fisiológicos e ignorar los filosóficos. En el presente trabajo, se delinea el contexto histórico del artículo de Ochorowicz, seguido de una traducción de su artículo. [ABSTRACT FROM AUTHOR]

Rationale: Little is known about acute effects of alcohol on memory encoding and retrieval on different limbs (ascending and descending) of the blood alcohol concentration (BAC) curve. Objectives: This extensive experiment was designed to examine alcohol's effects on memory encoding and retrieval throughout a protracted drinking episode. Methods: In a 9-h session, male participants consumed either alcohol (1 ml/kg) or placebo (n= 32/32) over a period of 90 min and learned various materials in different memory tasks before, during, and after consuming the drinks, while their BAC levels were monitored. A week later, in a similar session, they were tested on learned materials before, during, and after drinking. Mood was assessed throughout both sessions. Results: Alcohol impaired recall of words more than recognition, and cued recall most severely. Perceptual priming and picture recognition were not affected by alcohol. Alcohol impaired encoding in cued recall, recognition of completed word fragments, and free recall regardless of limb, but impaired retrieval in word recognition only during the ascending BAC. Alcohol increased negative mood on the descending limb during the first session, and on the ascending limb during the second session. Conclusions: Under naturalistic drinking conditions, alcohol's effects on memory depend on task, memory process, and limb of the BAC curve. The differential effects of alcohol on retrieval during the ascending and descending limbs demonstrate the importance of examining the differential effects on the two limbs. [ABSTRACT FROM AUTHOR]

This study explores implicit memory within the domain of text processing. Three experiments were designed to study cross-modality priming in a word-stem completion test following presentation of target words in the context of a coherent text. Four main results emerged. First, we found a significant priming effect for words previously studied in a text, this priming is higher with low-frequency words than with high-frequency words. Second, subjects demonstrated more repetition priming when study and test modalities matched than when they were different. Third, the magnitude of the priming effect in the visual condition varied with the perceptual processing of the text read. Fourth, priming effects did not depend on subjects' remembering of the words of text read as measured by a yes/no recognition test since no modality effect was found in this latter memory test. These results challenge Levy's (1993) view and are discussed in the framework of the transfer appropriate processing view proposed by Roediger, Weldon and Challis (1989). [ABSTRACT FROM AUTHOR]

Recollection of previously experienced events is a key element of human memory that entails recovery of spatial, perceptual, and mental state details. While deficits in this capacity in association with brain disease have serious functional consequences, little is known about individual differences in autobiographical memory (AM) in healthy individuals. Recently, healthy adults with highly superior autobiographical capacities have been identified (e.g., LePort, A.K., Mattfeld, A.T., Dickinson-Anson, H., Fallon, J.H., Stark, C.E., Kruggel, F., McGaugh, J.L., 2012. Behavioral and neuroanatomical investigation of Highly Superior Autobiographical Memory (HSAM). Neurobiol. Learn. Mem. 98(1), 78–92. doi: 10.1016/j.nlm.2012.05.002). Here we report data from three healthy, high functioning adults with the reverse pattern: lifelong severely deficient autobiographical memory (SDAM) with otherwise preserved cognitive function. Their self-reported selective inability to vividly recollect personally experienced events from a first-person perspective was corroborated by absence of functional magnetic resonance imaging (fMRI) and event-related potential (ERP) biomarkers associated with naturalistic and laboratory episodic recollection, as well as by behavioral evidence of impaired episodic retrieval, particularly for visual information. Yet learning and memory were otherwise intact, as long as these tasks could be accomplished by non-episodic processes. Thus these individuals function normally in day-to-day life, even though their past is experienced in the absence of recollection. [ABSTRACT FROM AUTHOR]

Background: leukocyte telomere length (TL) is considered a marker of biological aging. Several studies have investigated the link between leukocyte TL and aging-associated functional attributes of the brain, but no prior study has investigated whether TL can be linked to brain atrophy and white matter hyperintensities (WMHs); two prominent structural manifestations of brain aging.Methods: we investigated whether leukocyte TL was related to brain atrophy and WMHs in a sample of 102 non-demented individuals aged 64–75 years.Results: shorter TL was related to greater degree of subcortical atrophy (β = −0.217, P = 0.034), but not to cortical atrophy. Furthermore, TL was 371 bp shorter (P = 0.041) in participants exhibiting subcortical WMHs, and 552 bp shorter (P = 0.009) in older participants exhibiting periventricular WMHs.Conclusion: this study provides the first evidence of leukocyte TL being associated with cerebral subcortical atrophy and WMHs, lending further support to the concept of TL as a marker of biological aging, and in particular that of the aging brain. [ABSTRACT FROM AUTHOR]

Background: leukocyte telomere length (TL) is considered a marker of biological aging. Several studies have investigated the link between leukocyte TL and aging-associated functional attributes of the brain, but no prior study has investigated whether TL can be linked to brain atrophy and white matter hyperintensities (WMHs); two prominent structural manifestations of brain aging.Methods: we investigated whether leukocyte TL was related to brain atrophy and WMHs in a sample of 102 non-demented individuals aged 64–75 years.Results: shorter TL was related to greater degree of subcortical atrophy (β = −0.217, P = 0.034), but not to cortical atrophy. Furthermore, TL was 371 bp shorter (P = 0.041) in participants exhibiting subcortical WMHs, and 552 bp shorter (P = 0.009) in older participants exhibiting periventricular WMHs.Conclusion: this study provides the first evidence of leukocyte TL being associated with cerebral subcortical atrophy and WMHs, lending further support to the concept of TL as a marker of biological aging, and in particular that of the aging brain. [ABSTRACT FROM AUTHOR]

Abstract: The hippocampus (HC) interacts with distributed brain regions to support memory and shows significant volume reductions in aging, but little is known about age effects on hippocampal whole‐brain structural covariance. It is also unclear whether the anterior and posterior HC show similar or distinct patterns of whole‐brain covariance and to what extent these are related to memory functions organized along the hippocampal longitudinal axis. Using the multivariate approach partial least squares, we assessed structural whole‐brain covariance of the HC in addition to regional volume, in young, middle‐aged and older adults (n = 221), and assessed associations with episodic and spatial memory. Based on findings of sex differences in both memory and brain aging, we further considered sex as a potential modulating factor of age effects. There were two main covariance patterns: one capturing common anterior and posterior covariance, and one differentiating the two regions by capturing anterior‐specific covariance only. These patterns were differentially related to associative memory while unrelated to measures of single‐item memory and spatial memory. Although patterns were qualitatively comparable across age groups, participants' expression of both patterns decreased with age, independently of sex. The results suggest that the organization of hippocampal structural whole‐brain covariance remains stable across age, but that the integrity of these networks decreases as the brain undergoes age‐related alterations. [ABSTRACT FROM AUTHOR]

fMRI studies have identified distinct resting-state functional connectivity (RSFC) networks associated with the anterior and posterior hippocampus. However, the functional relevance of these two networks is still largely unknown. Hippocampal lesion studies and task-related fMRI point to a role for the anterior hippocampus in nonspatial episodic memory and the posterior hippocampus in spatial memory. We used Relevance Vector Regression (RVR), a machine-learning method that enables predictions of continuous outcome measures from multivariate patterns of brain imaging data, to test the hypothesis that patterns of whole-brain RSFC associated with the anterior hippocampus predict episodic memory performance, while patterns of whole-brain RSFC associated with the posterior hippocampus predict spatial memory performance. Magnetic resonance imaging and memory assessment took place at two separate occasions. The anterior and posterior RSFC largely corresponded with previous findings, and showed no effect of laterality. Supporting the hypothesis, RVR produced accurate predictions of episodic performance from anterior, but not posterior, RSFC, and accurate predictions of spatial performance from posterior, but not anterior, RSFC. In contrast, a univariate approach could not predict performance from resting-state connectivity. This supports a functional dissociation between the anterior and posterior hippocampus, and indicates a multivariate relationship between intrinsic functional networks and cognitive performance within specific domains, that is relatively stable over time. [ABSTRACT FROM AUTHOR]

Apolipoprotein E ( APOE ) ε4 has been associated with smaller hippocampal volumes in healthy aging, while findings in young adults are inconclusive. Previous studies have mostly used univariate methods, and without considering potential anterior/posterior differences. Here, we used a multivariate method, partial least squares, and assessed whole-brain structural covariance of the anterior (aHC) and posterior (pHC) hippocampus in young adults ( n = 97) as a function of APOE ε4 status and sex. Two significant patterns emerged: (1) specific structural covariance of the aHC with frontal regions, temporal and occipital areas in APOE ε4 women, whereas the volume of both the aHC and pHC in all other groups co-varied with frontal, parietal and cerebellar areas; and (2) opposite structural covariance of the pHC in ε4 carriers compared to the aHC in non-carriers, with the pHC of ε4 carriers covarying with parietal and frontal areas, and the aHC of ε4 non-carriers covarying with motor areas and the middle frontal gyrus. APOE ε4 has in young adults been associated with better episodic and spatial memory, functions involving the aHC and pHC, respectively. We found no associations between structural covariance and performance, suggesting that other factors underlie the performance differences seen between carriers and non-carriers. Our findings indicate that APOE ε4 carriers and non-carriers differ in hippocampal organization and that there are differences as a function of sex and hippocampal segment. They stress the need to consider the hippocampus as a heterogeneous structure, and highlight the benefits of multivariate methods in assessing group differences in the brain. [ABSTRACT FROM AUTHOR]

The anterior hippocampus has been implicated in associative memory, and along with hippocampal volume, this type of memory declines with age. However, few cross-sectional studies include middle-aged samples, making it unclear at what point these age-related changes occur. In addition, although men and women have been shown to differ in associative memory and rates of age-related hippocampal atrophy, sex-differences in aging are rarely studied. To address these issues, we assessed memory for word-pairs, hippocampal volume and activation during encoding and retrieval, across middle-aged (n = 39) and older (n = 44) participants, specifically in relation to sex. Older adults showed significantly poorer associative memory compared to middle-aged adults, paralleled by smaller anterior hippocampi and less activation during successful retrieval. The age-by-sex interaction observed in memory performance was also mirrored in the volume and activation of the hippocampus, indicating more pronounced age-effects in men as compared to women. These results indicate a specific role of the anterior hippocampus in verbal associative memory and suggest they both decline between middle-age and older age. [ABSTRACT FROM AUTHOR]

The apolipoprotein E ( APOE ) ϵ4 allele is known to be a major genetic risk factor for Alzheimer’s disease (AD). It has been linked to especially episodic memory decline and hippocampal atrophy in both healthy and demented elderly populations. In young adults, ϵ4 carriers have shown better performance in episodic memory compared to non-carriers. Spatial memory, however, has not been thoroughly assessed in relation to APOE in spite of its dependence on the hippocampus. In this study, we assessed the effect of APOE genotype on a variety of spatial and episodic memory tasks as well as hippocampal volume assessed through manual tracing in a sample of young adults ( N = 123). We also assessed whether potential effects were modulated by sex. The presence of one or more ϵ4 alleles had positive effects on spatial function and memory and object location memory, but no effect on word recognition. Men were superior to women in spatial function and memory but there were no sex differences in the other tasks. In spite of APOE ϵ4 carriers having superior performance in several memory tasks, no difference was found as a function of APOE genotype in hippocampal volume. To our knowledge, this study is the first to show that APOE ϵ4 has a positive effect on spatial ability in young adults. [ABSTRACT FROM AUTHOR]

Sex differences in episodic and spatial memory are frequently observed, suggesting that there may be sex-related structural differences in the hippocampus (HC). Earlier findings are inconsistent, possibly due to a known variability along the hippocampal longitudinal axis. Here, we assessed potential sex differences in hippocampal volume and structural covariance with the rest of the brain in young men and women (N=76), considering the anterior (aHC) and posterior (pHC) hippocampus separately. Women exhibited a larger pHC than men adjusted for brain size. Using partial least squares, we identified two significant patterns of structural covariance of the aHC and pHC. The first included brain areas that covaried positively and negatively in volume with both the aHC and pHC in men, but showed greater covariance with the aHC than pHC in women. The second pattern revealed distinct structural covariance of the aHC and pHC that showed a clear difference between men and women: in men the pHC showed reliable structural covariance with the medial and lateral parietal lobes and the prefrontal cortex, whereas in women the aHC showed reliable structural covariance with the anterior temporal lobe bilaterally. This pattern converges with resting state functional connectivity of the aHC and pHC and suggests that these hippocampal sections interact with different brain regions, consistent with a division of labor with regards to episodic and spatial memory. Our findings lend support to a division of the HC into an anterior and posterior part and identify sex as a potential moderating factor when investigating hippocampal structure and connectivity. [ABSTRACT FROM AUTHOR]

Highlights: [•] We investigate neural correlates of sex differences in spatial memory. [•] Men are better than women at recalling their starting location. [•] Both men and women activate the posterior hippocampus during the task. [•] Men show a right-lateralization in activity not present in women. [•] Greater right-lateralization is associated with better performance. [ABSTRACT FROM AUTHOR]