Dynamics of Hippocampal and Cortical Activation during Consolidation of a Nonspatial Memory

Observations of temporally graded retrograde amnesia after hippocampal damage suggest that the hippocampal region plays a critical, time-limited role in memory consolidation. However, these observations do not indicate where permanentmemory is stored, nor do they clarify whether the hippocampus normally remains involved in a nonessential way. Evidence from multiple neural imaging studies indicate the time-limited role of the hippocampus and suggest that the anterior cingulate cortex is a critical storage site of different types of long-term memory. However, each of the previous studies examined spatial memory, leaving open the question of whether different cortical areas support long-term memory for other types ofmaterial. We characterized the course of involvement of cortical and hippocampal areas in animals trained in an explicitlynonspatial task. First, we confirmed previous findings that hippocampal damage produces temporally graded retrogradeamnesia for the social transmission of a food preference (STFP) within our experimental protocol. Damage to thehippocampal region 1 d, but not 21 d, after training impaired subsequent recall of STFP. Then, we characterized theanatomical patterns of activation of the immediate early gene c-fos during retrieval of STFP immediately and 1, 2, and 21 dafter training. The ventral subiculum was activated during retrieval shortly after learning, but the level of activation declined at successive times. In contrast, olfactory recipient regions including piriform, entorhinal, and orbitofrontal cortex showed the opposite pattern, increasingly greater activation in successively later retrieval tests. These findings support the view that different cortical networks support long-term memory for different types of information

The Hippocampus is Preferentially Associated with Memory for Spatial Context

The existence of a functional-anatomic dissociation for retrieving item versus contextual information within subregions of the medial temporal lobe (MTL) is currently under debate. We used a spatial source memory paradigm during event-related functional magnetic resonance imaging to investigate this issue. At study, abstract shapes were presented to the left or right of fixation. During test, old and new shapes were presented at fixation. Participants responded whether each shape had been previously presented on the “left,” the “right,” or was “new.” Activity associated with contextual memory (i.e., source memory) was isolated by contrasting accurate versus inaccurate memory for spatial location. Item-memory-related activity was isolated by contrasting accurate item recognition without contextual memory with forgotten items. Source memory was associated with activity in the hippocampus and parahippocampal cortex. Although item memory was not associated with unique MTL activity at our original threshold, a region-of-interest (ROI) analysis revealed item-memory-related activity in the perirhinal cortex. Furthermore, a functional-anatomic dissociation within the parietal cortex for retrieving item and contextual information was not found in any of three ROIs. These results support the hypothesis that specific subregions in the MTL are associated with item memory and memory for context

Managing A Changing Relationship: China's Japan Policy in the 1990s

This paper was prepared for the conference on "China into the twenty-first century: Strategic partner and...or peer competitor

Nationalism, Geopolitics, and Naval Expansionism From the Nineteenth Century to the Rise of China

Naval nationalism can encourage expansionist maritime policies, which can force acquisitions that are not informed by strategic interests and that ultimately undermine security and contribute to unnecessary and costly great-power conflict

The New Left and the Human Service Professions

There are three characteristics of the New Left which had impact on social and human service professionals. Egalitarianism produced distrustof orthodox professional detachment from and power over poor and minority persons. The movement also gave expression to guilt, for some, over their privileged backgrounds. The New Left\u27s decentralist views about power produced an orientation to local insurgency: the organization of neighborhood and community activist organizations. In combination, for those influenced by the movement and entering the professions, a characteristic type of new professionalism arose: advocacy for the interests and organizations of the oppressed. Illustrations of this process are found in city planning and the academic disciplines, as well as other traditional and social service professions

Problems of Advocacy

The recent past has seen the erosion, and among some, the rejection, of social science neutrality and professional detachment. Among the typical expressions of a new professionalism is the underdog advocate, who wishes to lend his or her skills to the cause of less-than-equal groups in the society. The paper analyzes the problems confronting such advocates. The first is the discrepancy between career routes and success behavior on one hand, and the needs of poor people on the other. The second is the difficulty encountered by middle strata professionals in cross-class and cross-cultural communication, including their own ignorance of the structure and dynamics of minority and poor peoples\u27 communities. The third problem faced by the advocates is that the mere addition of their expert skills to the struggles of the deprived is not necessarily or usually adequate in terms of power resources. If advocates have, however, a modest definition of their possible accomplishment, and if they view underprivileged groups as the main actors in their own behalf, their roles may be defined more realistically

Managing a Changing Relationship: China\u27s Japan Policy in the 1990s

In April 1996, the Army War College\u27s Strategic Studies Institute held its Seventh Annual Strategy Conference. This year\u27s theme was, China into the 21st Century: Strategic Partner and…or Peer Competitor. The author of the following monograph, Dr. Robert S. Ross, of Harvard University\u27s Fairbank Center for East Asian Research, argues that Japan\u27s relationship with China is a key element in the evolving East Asian security structure. From Beijing\u27s perspective, China\u27s Japan policy rivals its relationship with the United States in relative strategic importance. Japan\u27s economic strength and its potential military power make it a major factor in Chinese security calculations. Many of the same factors that affect Sino-American relations and Sino-Russian relations are integral to the relationship between Beijing and Tokyo. Among these are Chinese treatment of dissidents, the Taiwan issue, economic investment, and Japanese military policy and strategy. Today Japanese and Chinese interests compete in many areas, requiring tolerance, patience and diplomatic sophistication to keep competition from evolving into conflict. In the future, these challenges are likely to grow in complexity.https://press.armywarcollege.edu/monographs/1873/thumbnail.jp

Altered intrinsic functional coupling between core neurocognitive networks in Parkinson\u27s disease

Parkinson3s disease (PD) is largely attributed to disruptions in the nigrostriatal dopamine system. These neurodegenerative changes may also have a more global effect on intrinsic brain organization at the cortical level. Functional brain connectivity between neurocognitive systems related to cognitive processing is critical for effective neural communication, and is disrupted across neurological disorders. Three core neurocognitive networks have been established as playing a critical role in the pathophysiology of many neurological disorders: the default-mode network (DMN), the salience network (SN), and the central executive network (CEN). In healthy adults, DMN–CEN interactions are anti-correlated while SN–CEN interactions are strongly positively correlated even at rest, when individuals are not engaging in any task. These intrinsic between-network interactions at rest are necessary for efficient suppression of the DMN and activation of the CEN during a range of cognitive tasks. To identify whether these network interactions are disrupted in individuals with PD, we used resting state functional magnetic resonance imaging (rsfMRI) to compare between-network connectivity between 24 PD participants and 20 age-matched controls (MC). In comparison to the MC, individuals with PD showed significantly less SN–CEN coupling and greater DMN–CEN coupling during rest. Disease severity, an index of striatal dysfunction, was related to reduced functional coupling between the striatum and SN. These results demonstrate that individuals with PD have a dysfunctional pattern of interaction between core neurocognitive networks compared to what is found in healthy individuals, and that interaction between the SN and the striatum is even more profoundly disrupted in those with greater disease severity

Tectonics of the western Gulf of Oman

Also published as: Journal of Geophysical Research 84 (1979): 3479-3489The Oman line, running northward from the Strait of Hormuz separates a continent‐continent plate boundary to the northwest (Persian Gulf region) from an ocean‐continent plate boundary to the southeast (Gulf of Oman region). A large basement ridge detected on multichannel seismic reflection and gravity profiles to the west of the Oman line is probably a subsurface continuation of the Musandam peninsula beneath the Strait of Hormuz. Collision and underthrusting beneath Iran of the Arabian plate on which this ridge lies has caused many of the large earthquakes that have occurred in this region. Convergence between the oceanic crust of the Arabian plate beneath the Gulf of Oman and the continental Eurasian plate beneath Iran to the north is accommodated by northward dipping subduction. A deformed sediment prism which forms the offshore Makran continental margin and which extends onto land in the Iranian Makran has accumulated above the descending plate. In the western part of the Gulf of Oman, continued convergence has brought the opposing continental margin of Oman into contact with the Makran continental margin. This is an example of the initial stages of a continent‐continent type collision. A model of imbricate thrusting is proposed to explain the development of the fold ridges and basins on the Makran continental margin. Sediments from the subducting plate are buckled and incorporated into the edge of the Makran continental margin in deformed wedges and subsequently uplifted along major faults that penetrate the accretionary prism further to the north.Prepared for the Office of Naval Research under Contract N00014-74-C-0262; NR 083-004 and for the National Science Foundation under Grant 76-10417

Corn production : a 4-H project

November, 1949."University of Missouri College of Agriculture and the United States Department of Agriculture Cooperating"--Page [12].Title from caption