The PFC, through its high degree of interconnectivity with cortical and subcortical brain areas, mediates cognitive and emotional processes in support of adaptive behaviors. This includes the formation of fear memories when the anticipation of threat demands learning about temporal or contextual cues, as in trace fear conditioning. In this variant of fear learning, the association of a cue and shock across an empty trace interval of several seconds requires sustained cue-elicited firing in the prelimbic cortex (PL). However, it is unknown how and when distinct PL afferents contribute to different associative components of memory. Among the prominent inputs to PL, the hippocampus shares with PL a role in both working memory and contextual processing. Here we tested the necessity of direct hippocampal input to the PL for the acquisition of trace-cued fear memory and the simultaneously acquired contextual fear association. Optogenetic silencing of ventral hippocampal (VH) terminals in the PL of adult male Long-Evans rats selectively during paired trials revealed that direct communication between the VH and PL during training is necessary for contextual fear memory, but not for trace-cued fear acquisition. The pattern of the contextual memory deficit and the disruption of local PL firing during optogenetic silencing of VH-PL suggest that the VH continuously updates the PL with the current contextual state of the animal, which, when disrupted during memory acquisition, is detrimental to the subsequent rapid retrieval of aversive contextual associations.

SIGNIFICANCE STATEMENT Learning to anticipate threat from available contextual and discrete cues is crucial for survival. The prelimbic cortex is required for forming fear memories when temporal or contextual complexity is involved, as in trace fear conditioning. However, the respective contribution of distinct prelimbic afferents to the temporal and contextual components of memory is not known. We report that direct input from the ventral hippocampus enables the formation of the contextual, but not trace-cued, fear memory necessary for the subsequent rapid expression of a fear response. This finding dissociates the contextual and working-memory contributions of prelimbic cortex to the formation of a fear memory and demonstrates the crucial role for hippocampal input in contextual fear learning.

Pattern separation and completion are fundamental hippocampal computations supporting memory encoding and retrieval. However, despite extensive exploration of these processes, it remains unclear whether and how top-down processes adaptively modulate the dynamics between these computations. Here we examine the role of expectation in shifting the hippocampus to perform pattern separation. In a behavioral task, 29 participants (7 males) learned a cue-object category contingency. Then, at encoding, one-third of the cues preceding the to-be-memorized objects, violated the studied rule. At test, participants performed a recognition task with old objects (targets) and a set of parametrically manipulated (very similar to dissimilar) foils for each object. Accuracy was found to be better for foils of high similarity to targets that were contextually unexpected at encoding compared with expected ones. Critically, there were no expectation-driven differences for targets and low similarity foils. To further explore these effects, we implemented a computational model of the hippocampus, performing the same task as the human participants. We used representational similarity analysis to examine how top-down expectation interacts with bottom-up perceptual input, in each layer. All subfields showed more dissimilar representations for unexpected items, with dentate gyrus (DG) and CA3 being more sensitive to expectation violation than CA1. Again, representational differences between expected and unexpected inputs were prominent for moderate to high levels of input similarity. This effect diminished when inputs from DG and CA3 into CA1 were lesioned. Overall, these novel findings strongly suggest that pattern separation in DG/CA3 underlies the effect that violation of expectation exerts on memory.

SIGNIFICANCE STATEMENT What makes some events more memorable than others is a key question in cognitive neuroscience. Violation of expectation often leads to better memory performance, but the neural mechanism underlying this benefit remains elusive. In a behavioral study, we found that memory accuracy is enhanced selectively for unexpected highly similar foils, suggesting expectation violation does not enhance memory indiscriminately, but specifically aids the disambiguation of overlapping inputs. This is further supported by our subsequent investigation using a hippocampal computational model, revealing increased representational dissimilarity for unexpected highly similar foils in DG and CA3. These convergent results provide the first evidence that pattern separation plays an explicit role in supporting memory for unexpected information.

Preterm born children have cognitive problems that include deficits in working memory. Computer-based working memory training has been reported to improve cognitive function in children.

A computer-based working memory training program designed for preschoolers seems effective in very low birth weight children, not only on working memory tasks, but also by having a generalizing effect regarding memory and learning. (Read the full article)

You don't have to fork over a bunch of cash to get a bunch of storage. PNY flash drives, SD cards, and portable drives are on sale at Amazon, with prices starting as low as $5.84.

A look back at prior attempts to renew the federal law makes one thing clear: We're drifting further and further away from the idea of a strong federal role in K-12 accountability.

By manipulating the expression of one gene, geneticists can induce a form of “stress memory” in plants that is inherited by some progeny, giving them the potential for more vigorous, hardy and productive growth, according to Penn State researchers, who suggest the discovery has significant implications for plant breeding.

Mark Alpert made a generous gift $200,000 in memory of his late wife, Claire, to establish the Mark E. and Claire L. Alpert Graduate Fellowship in the Department of Civil and Environmental Engineering at Penn State.

"Rest in peace my dear friend," Deepika had written earlier

"Rest in peace my dear friend," Deepika had written earlier

With the passing of former President George H. W. Bush on November 30, 2018 President Trump has ordered United States flags at all government buildings and facilities be flown at half-staff beginning immediately in honor and tribute to the memory of President George H.W. Bush, and as an expression of public sorrow. In concurrence with […]

Senior Jack Boyle's game-winning buzzer-beater sent Pomona-Pitzer to the Division III Sweet 16. But due to the pandemic, it would be his last shot.

Hi Folks, A question that I've often received from designers, "Is there a method to determine the amount of memory required before I submit a job? I use distributed processing and need to provide an estimate before submitting jobs." The answer...(read more)

ncsim will consume an increasing ammount of memory when a function has an output port that return an associative array which was not initialized. My simulator version is 12.10-s011.

Below is a code example to reproduce the failure. The code is inside a class (uvm_object):

function void a_function(output bit ret_val[int]);

// empty 

endfunction : get_cov

When the Arduino Mega2560 is added to the first serial port, the dynamic memory is 2000 bytes, and when the second serial serial is added, the dynamic memory is 4000 bytes. Now I need to add the third Serial serial port. The dynamic memory is 6000 bytes. Due to the many variables in the program itself, the dynamic memory is not enough. Please help me how to save the dynamic memory?

launchd on macOS and iOS suffer from a memory corruption issue due to a lack of bounds checking when parsing XPC messages.

macOS and iOS have a vulnerability with ImageIO where memory safety issues occur when processing OpenEXR images.

Whitepaper called Blue Team vs. Red Team: How to run your encrypted binaries in memory and go undetected. This paper discusses the golden frieza project.

The ByteComponentRaster.verify() method in Oracle Java versions prior to 7u25 is vulnerable to a memory corruption vulnerability that allows bypassing of "dataOffsets[]" boundary checks. This exploit code demonstrates remote code execution by popping calc.exe. It was obtained through the Packet Storm Bug Bounty program.

The ShortComponentRaster.verify() method in Oracle Java versions prior to 7u25 is vulnerable to a memory corruption vulnerability that allows bypassing of "dataOffsets[]" boundary checks when the "numDataElements" field is 0. This exploit code demonstrates remote code execution by popping calc.exe. It was obtained through the Packet Storm Bug Bounty program.

This exploit leverages both invalid typecast and memory disclosure vulnerabilities in Microsoft Silverlight 5 in order to achieve code execution. This exploit code demonstrates remote code execution by popping calc.exe. It was obtained through the Packet Storm Bug Bounty program. Google flags this as malware so only use this if you know what you are doing. The password to unarchive this zip is the word "infected".

Microsoft Silverlight 5 suffers from invalid typecast and memory disclosure vulnerabilities that, when leveraged together, allow for arbitrary code execution. A memory disclosure vulnerability exists in the public WriteableBitmap class from System.Windows.dll. This class allows reading of image pixels from the user-defined data stream via the public SetSource() method. BitmapSource.ReadStream() allocates and returns byte array and a count of array items as out parameters. These returned values are taken from the input stream and they can be fully controlled by the untrusted code. When returned "count" is greater than "array.Length", then data outside the "array" are used as input stream data by the native BitmapSource_SetSource() from agcore.dll. Later all data can be viewed via the public WriteableBitmap.Pixels[] property. Exploitation details related to these findings were purchased through the Packet Storm Bug Bounty program.

This Metasploit module exploits a vulnerability on Microsoft Silverlight. The vulnerability exists on the Initialize() method from System.Windows.Browser.ScriptObject, which access memory in an unsafe manner. Since it is accessible for untrusted code (user controlled) it's possible to dereference arbitrary memory which easily leverages to arbitrary code execution. In order to bypass DEP/ASLR a second vulnerability is used, in the public WriteableBitmap class from System.Windows.dll. This Metasploit module has been tested successfully on IE6 - IE10, Windows XP SP3 / Windows 7 SP1 on both x32 and x64 architectures.

The Microsoft Windows kernel suffers from a 64-bit pool memory disclosure vulnerability via REG_RESOURCE_LIST registry values (CmResourceTypeDevicePrivate entries).

The Microsoft Windows kernel suffers from a 64-bit pool memory disclosure vulnerability via REG_RESOURCE_LIST registry values (videoprt.sys descriptors).

The Microsoft Windows kernel suffers from a 64-bit pool memory disclosure vulnerability via REG_RESOURCE_REQUIREMENTS_LIST registry values.

Qualys has discovered a memory leak and a buffer overflow in the dynamic loader (ld.so) of the GNU C Library (glibc).

GNU Barcode version 0.99 suffers from a memory leak vulnerability.

ImageMagick versions prior to 7.0.8-9 suffers from a memory leak vulnerability.

LibTIFF version 4.0.8 suffers from multiple memory leak vulnerabilities.

KVM suffers from an uninitialized memory leak vulnerability in kvm_inject_page_fault.

An information disclosure vulnerability exists when Centaur and TitanSMA fail to properly protect critical system logs such as 'syslog'. Additionally, the implemented Jetty version (9.4.z-SNAPSHOT) suffers from a memory leak of shared buffers that was (supposedly) patched in Jetty version 9.2.9.v20150224.

Nanometrics Centaur version 4.3.23 suffers from an unauthenticated remote memory leak vulnerability.

IRIX suffers from local kernel memory disclosure and denial of service vulnerabilities.

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Little mental challenges can also be both beneficial and fun.

PIC18F2X/4XQ10 Memory Programming Specification

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Protect Against Rootkit and Bootkit Malware in Systems that Boot from External SPI Flash Memory

SST Announces Automotive Grade 1 Qualification of Embedded SuperFlash® Memory on UMC’s 55 nm Platform

Microchip Honored with Best of Show Award at Flash Memory Summit 2019

Memory Products MCC Library V2.4.0

SAMRH71 Using ICC and ECC for Efficient Memory Scrubbing

A communications network secured by the laws of quantum physics would be unhackable, but building one requires a component called a quantum memory, which is still being developed

More than half of us breathe the wrong way, missing out on many benefits from better health to altered consciousness. Here's how to do it right