Memory systems

Membrane transport Memory Memory banks Memory device Memory-enhancing drug Memory-impairment Memory protection Memory storage device Memory systems Menadione... 

Magnetooptic Materials. The appHcation of magnetooptic effects to optical memory systems, such as for laser beam writing and magnetooptic read, has been the subject of much research. Magnetooptic storage media offer the potential of storing over 120 Mbit/cm of information without contact of the read/write head which would thus be very competitive to floppy disks and tape. 

Transputers. At higher levels of coimectedness there is a wide variety of parallel computers. A great many parallel computers have been built using INMOS Transputer chips. Individual Transputer chips mn at 2 MELOPS or greater. Transputer chips have four communication channels, so the chips can readily be intercoimected into a two-dimensional mesh network or into any other interconnection scheme where individual nodes are four-coimected. Most Transputer systems have been built as additions to existing host computers and are SIMD type. Each Transputer has a relatively small local memory as well as access to the host s memory through the interconnection network. Not surprisingly, problems that best utilize local memory tend to achieve better performance than those that make more frequent accesses to host memory. Systems that access fast local memory and slower shared memory are often referred to as NUMA, nonuniform memory access, architecture. 

Yates, Frances Amelia. The stage in Robert Fludd s memory system. Shakespeare Studs 3 (1967) 138-166. 

Robbins, T.W., Everitt, B J. Limbic-striatal memory systems and drug addiction. Neurobiol. Learn. Mem. 78 625, 2002. 

Nissen MJ, Knopman DS and Schacter DL (1987). Neurochemical dissociation of memory systems. Neurology, 37, 789-794. 

Brennan, P., Kaba, H. and Keveme, E.B. (1990) Olfactory Recognition a simple memory system. Science 250, 1223-1226. 

Chang Q, Gold P. 2003. Switching memory systems during learning Changes in patterns of brains acetylcholine release... 

McIntyre C, Marriott L, Gold P. 2003a. Cooperation between memory systems Acetylcholine release in the amygdala correlates positively with performance on a hippocampus-dependent task. Behavioral Neuroscience 117(2) 320-326. 

Packard M, Cahill L. 2001. Affective modulation of multiple memory systems. Curr Opin Neurobiol 11(6) 752-756. 

White N, McDonald R. 2002. Multiple parallel memory systems in the brain of the rat. Neurobiol Learn Mem 77(2) 125-184. 

Accumulation and reorganization of information can also be achieved on the basis of cis-trans isomerization of olefins in their ion-radical states. An application of the phenomenon in real electron memory systems was claimed (Todres 2001). For the neutral arylethylenes, conversion from... 

Exploiting arylethylenes as bearers of electron memory has the following advantages First, the compounds are commercially available and inexpensive. Second, they work for very long time. Third, transformation of the information recorded is simple and consumes little energy. In other words, creation of electron memory systems through ion-radical route is fruitful. 

Staubli, U., Fraser, D., Faraday, R. and Lynch, G. (1987). Olfactionand the data memory system in rats. Behavioral Neuroscience 101,757-765. 

Desgranges B, Baron JC, de la SayetteV, The neural substrates of memory systems impairment in Alzheimer s disease, 121 611—631, 1998. 

In Table 1 we compare performance data for reported MRAM and FRAM prototypes. The small Fujitsu FRAM is not a prototype it is in large-scale production and found in the memory board of every Sony Playstation 2, as part of the Toshiba memory system. The main advantages of FRAMs over EEP-ROMs or Elash memory are in the WRITE times (100 ns for FRAM, versus 1 xs for Flash and 10 xs for EEPROM), and energy per 32-bit WRITE (1 nj for ERAM versus 1 or 2 mj for EEPROM or Plash). Note that parameters such as READ time or WRITE time for PRAMs are dependent upon actual cell architecture they are not limited by the intrinsic switching time of the ferroelectric thin film, which is typically 220 ps [3]. 

The state of conscious awareness, with orientation of self in time and space, depends on hnely tuned and accurately co-ordinated activity in multiple neuronal networks in the brain (Park Young, 1994). Such activity involves parallel processing in many cortical and subcortical pathways including arousal and memory systems (Chapters 3 and 4) and systems involved in mood (Chapters 5 and 18) and utilises an orchestra of many neurotransmitters. The whole ensemble appears to be synchronised by high frequency (40+ Hz) oscillatory electrical activity which binds the component parts together (Llinas et ah, 1998 Tallon-Baudry Bertrand, 1999). 

For human beings, two different memory categories have been introduced. According to Schacter, imphcit (or unconscious/unaware) memory is revealed when previous experiences facilitate performance on a task that does not require conscious or intentional recollection of those experiences. Explicit memory, in turn, is revealed when the performance of a task requires conscious recollection of previous experiences. These are descriptive concepts that are primarily concerned with a person s psychological experience at the time of memory retrieval. Accordingly, the concepts of implicit and expUcit memory neither refer to nor imply the existence of two independent or separate memory systems (Schacter 1987). As these two memory categories cannot be easily appHed to the situation in animals, they will not be further considered in this chapter. 

Eichenbaum H, Cohen NJ (2001) From conditioning to conscious recollection. Memory systems of the brain. Oxford University Press, New York Eisenberg M, Kobilo T, Berman DE, Dudai Y (2003) Stability of retrieved memory inverse correlation with trace dominance. Science 301 1102-1104 Fanselow MS (1994) Neural organization of the defensive behavior system responsible for fear. Psychon Bull Rev 1 429-438... 

Incongruities such as the dream character who has the physical attributes of one person that we know and the face of another illustrate an indiscriminate but perhaps functionally significant over-inclusiveness in the categories of unconscious memory systems. We can get at this process by using semantic memory tests of subjects awakened from REM and tested both immediately and later when the sleep inertia is over. Compared to waking and to NREM sleep, we find the expected REM enhancement of weak primes (i.e., loose associations) but, to our surprise, not of strong primes (strong associations). 

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