Home About us Contact
|
Home About us Contact | ||
|
|
||
Memory Processing (memory + processing)
Selected AbstractsBinge Drinking Affects Attentional and Visual Working Memory Processing in Young University StudentsALCOHOLISM, Issue 11 2009Alberto Crego Background:, Binge Drinking (BD) typically involves heavy drinking over a short time, followed by a period of abstinence, and is common among young people, especially university students. Animal studies have demonstrated that this type of alcohol consumption causes brain damage, especially in the nonmature brain. The aim of the present study was to determine how BD affects brain functioning in male and female university students, during the performance of a visual working memory task. Methods:, Event-related potentials (ERPs) were recorded, with an extensive set of 32 scalp electrodes, in 95 first-year university students (age range 18 to 20 years), comprising 42 binge drinkers (BD) and 53 controls, in a visual "identical pairs" continuous performance task. Principal components analysis was used to identify and analyze the N2 (negative waveform with a latency around 200 to 300 ms related to attentional processes) and P3 (positive waveform with a latency around 300 to 600 ms related to working memory processes) components of the ERPs. Results:, In the matching condition of the task, the N2 component in central and parietal regions was significantly larger in the BD than in the control group. In the control group, the P3 component was larger in the matching than in the nonmatching condition in the frontal, central, and parietal regions, whereas the BD group did not show any significant differences between conditions in any region. Conclusions:, The results of this study confirm the presence of electrophysiological differences between young university student binge drinkers and controls during the execution of a visual task with a high working memory load. The larger N2 in the BD group suggests higher levels of attentional effort required by this group to perform the task adequately. The absence of any differences in the P3 component in the different conditions (matching and nonmatching stimuli) in the BD group suggests a deficiency in the electrophysiological differentiation between relevant and irrelevant information, which may reflect some impairment of working memory processes. [source] Two-way active avoidance training-specific increases in phosphorylated cAMP response element-binding protein in the dorsal hippocampus, amygdala, and hypothalamusEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2005Subhash Saha Abstract Previous studies have demonstrated that the activation of pontine-wave (P-wave) generating cells in the brainstem during post-training rapid eye movement (REM) sleep is critical for the consolidation of memory for two-way active avoidance (TWAA) learning in the rat. Here, using immunocytochemistry, we investigated the spatio-temporal distribution of CREB phosphorylation within different parts of the dorsal hippocampus, amygdala, and hypothalamus following a session of TWAA training in the rat. We show that the TWAA training trials increased phosphorylation of CREB (p-CREB) in the dorsal hippocampus, amygdala, amygdalo-hippocampal junction (AHi), and hypothalamus. However, the time intervals leading to training-induced p-CREB activity were different for different regions of the brain. In the dorsal hippocampus, p-CREB activity was maximal at 90 min and this activity disappeared by 180 min. In the AHi, activity of the p-CREB peaked by 180 min and disappeared by 360 min. In the amygdala, the p-CREB activity peaked at 180 min and still remained higher than the control at the 360 min interval. In the hypothalamus, at 90 min p-CREB activity was present only in the ventromedial hypothalamus; however, by 180 min this p-CREB activity was also present in the dorsal hypothalamus, perifornical area, and lateral hypothalamus. By 360 min, p-CREB activity disappeared from the hypothalamus. This TWAA training trials-induced spatiotemporal characteristic of CREB phosphorylation, for the first time, suggests that REM sleep P-wave generator activation-dependent memory processing involves different parts of the dorsal hippocampus, amygdala, and hypothalamus. [source] Changes in NOS protein expression and activity in the rat hippocampus, entorhinal and postrhinal cortices after unilateral electrolytic perirhinal cortex lesionsHIPPOCAMPUS, Issue 5 2003Ping Liu Abstract The integrity of the perirhinal cortex is critical for certain types of learning and memory. One important issue relating to the function of this region is its interaction with other brain areas that play a role in memory processing. This study investigates the time course of changes in activity and protein expression of nitric oxide synthase (NOS), which transforms L -arginine into nitric oxide (NO) and citrulline, in the hippocampus and the entorhinal and postrhinal cortices after unilateral electrolytic lesions of the perirhinal cortex. Electrolytic lesions of the perirhinal cortex resulted in long lasting changes in NOS activity and protein expression in the entorhinal and postrhinal cortices (,2 weeks post-lesion). In contrast, there was a small and transient decrease in nNOS expression (with no change in NOS activity) in the dorsal portion of the hippocampus. iNOS was not expressed in any region examined at any time point. These findings provide the first evidence that electrolytic lesions of the perirhinal cortex can result in long-term neurochemical changes in its anatomically related structures. Given that NO has been implicated in neuroplasticity processes, the interpretation of memory impairments induced by electrolytic lesions of the perirhinal cortex (and possibly, therefore, other brain regions) need to be considered with regard to these findings. Hippocampus 2003;13:561,571. © 2003 Wiley-Liss, Inc. [source] Reversible inactivation of the hippocampal formation in food-storing black-capped chickadees (Poecile atricapillus)HIPPOCAMPUS, Issue 4 2003Michael W. Shiflett Abstract The role of the hippocampal formation (HF) in memory processing was assessed in food-storing black-capped chickadees (Poecile atricapilla) by reversibly inactivating the HF during different memory tests. The memory tests required birds to remember a location based on spatial cues only, or based on a combination of both spatial and distinct visual cues. Inactivation of the HF impaired short-term spatial memory, but not visual-spatial memory. Inactivation of the HF impaired the retrieval of short-term (15 min) spatial memories, but not long-term (3-h) spatial memories. The pattern of deficits produced by inactivation of the HF in chickadees suggests a possible function of the hippocampal specialization of food-storing birds, as well as extends the notion of functional homology between the avian and mammalian HF. Hippocampus 2003;13:437,444. © 2003 Wiley-Liss, Inc. [source] Octopus Gonadotrophin-Releasing Hormone: A Multifunctional Peptide in the Endocrine and Nervous Systems of the CephalopodJOURNAL OF NEUROENDOCRINOLOGY, Issue 4 2009H. Minakata The optic gland, which is analogous to the anterior pituitary in the context of gonadal maturation, is found on the upper posterior edge of the optic tract of the octopus Octopus vulgaris. In mature octopus, the optic glands enlarge and secrete a gonadotrophic hormone. A peptide with structural features similar to that of vertebrate gonadotophin-releasing hormone (GnRH) was isolated from the brain of octopus and was named oct-GnRH. Oct-GnRH showed luteinising hormone-releasing activity in the anterior pituitary cells of the Japanese quail Coturnix coturnix. Oct-GnRH immunoreactive signals were observed in the glandular cells of the mature optic gland. Oct-GnRH stimulated the synthesis and release of sex steroids from the ovary and testis, and elicited contractions of the oviduct. Oct-GnRH receptor was expressed in the gonads and accessory organs, such as the oviduct and oviducal gland. These results suggest that oct-GnRH induces the gonadal maturation and oviposition by regulating sex steroidogenesis and a series of egg-laying behaviours via the oct-GnRH receptor. The distribution and expression of oct-GnRH in the central and peripheral nervous systems suggest that oct-GnRH acts as a multifunctional modulatory factor in feeding, memory processing, sensory, movement and autonomic functions. [source] No persisting effect of partial sleep curtailment on cognitive performance and declarative memory recall in adolescentsJOURNAL OF SLEEP RESEARCH, Issue 1-Part-I 2010MARTA KOPASZ Summary Growing evidence indicates that sleep facilitates learning and memory processing. Sleep curtailment is increasingly common in adolescents. The aim of this study was to examine the effects of short-term sleep curtailment on declarative memory consolidation in adolescents. A randomized, cross-over study design was chosen. Twenty-two healthy subjects, aged 14,16 years, spent three consecutive nights in the sleep laboratory with a bedtime of 9 h during the first night (adaptation), 4 h during the second (partial sleep curtailment) and 9 h during the third night (recovery). The control condition consisted of three consecutive nights with bedtimes of 9 h. Both experimental conditions were separated by at least 3 weeks. The acquisition phase for the declarative tests was between 16:00 and 18:00 hours before the second night. Memory performance was examined in the morning after the recovery night. Executive function, attention and concentration were also assessed to control for any possible effects of tiredness. During the 4-h night, we observed a curtailment of 50% of non-rapid eye movement (non-REM), 5% of slow wave sleep (SWS) and 70% of REM sleep compared with the control night. Partial sleep curtailment of one night did not influence declarative memory retrieval significantly. Recall in the paired-associate word list task was correlated positively with percentage of non-REM sleep in the recovery night. Declarative memory consolidation does not appear to be influenced by short-term sleep curtailment in adolescents. This may be explained by the high ability of adolescents to compensate for acute sleep loss. The correlation between non-REM sleep and declarative memory performance supports earlier findings. [source] Recall and recognition of brand names: A comparison of word and nonword name typesPSYCHOLOGY & MARKETING, Issue 7-8 2002Dawn Lerman Despite the common recommendation that brand names be memorable, little is known about the effect of brand name type on various forms of memory processing such as recall and recognition. As such, this article extends prior research by comparing recall and recognition for three sets of brand names: words versus nonwords, relevant (i.e., related to a product attribute) words versus irrelevant (i.e., unrelated to a product attribute) words, and relevant words cuing an advertised attribute versus relevant words cuing an unadvertised attribute. The results of an experimental study indicate that memory for these brand name types depends on whether it is accessed via recall or recognition. Based on these results, implications for naming new products are discussed. © 2002 Wiley Periodicals, Inc. [source] Cytoarchitectonic and chemoarchitectonic subdivisions of the perirhinal and parahippocampal cortices in macaque monkeysTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 6 2007Kadharbatcha S. Saleem Abstract Although the perirhinal and parahippocampal cortices have been shown to be critically involved in memory processing, the boundaries and extent of these areas have been controversial. To produce a more objective and reproducible description, the architectonic boundaries and structure of the perirhinal (areas 35 and 36) and parahippocampal (areas TF and TH) cortices were analyzed in three macaque species, with four different staining methods [Nissl and immunohistochemistry for parvalbumin, nonphosphorylated neurofilaments (with SMI-32), and the m2 muscarinic acetylcholine receptor]. We further correlated the architectonic boundary of the parahippocampal cortex with connections to and from different subregions of anterior area TE and with previously published connections with the prefrontal cortex and temporal pole (Kondo et al. [2005] J. Comp. Neurol. 493:479,509). Together, these data provided a clear delineation of the perirhinal and parahippocampal areas, although it differs from previous descriptions. In particular, we did not extend the perirhinal cortex into the temporal pole, and the lateral boundaries of areas 36 and TF with area TE were placed more medially than in other studies. The lateral boundary of area TF in Macaca fuscata was located more laterally than in Macaca fascicularis or Macaca mulatta, although there was no difference in architectonic structure. We recognized a caudal, granular part of the parahippocampal cortex that we termed "area TFO." This area closely resembles the laterally adjacent area TE and the caudally adjacent area V4 but is clearly different from the more rostral area TF. These areas are likely to have distinct functions. J. Comp. Neurol. 500:973,1006, 2007. © 2006 Wiley-Liss, Inc. [source] | |||||||||||||