Memory NetworksNeural NetworksDeep LearningTransformers

Engram: Memory Networks for AI

Research Team
2024
15 min read

Abstract

This paper introduces Engram, a novel approach to memory in neural networks that enables models to store, retrieve, and reason over memories in a differentiable manner. We explore how these memory mechanisms can improve performance on tasks requiring long-term dependencies and factual knowledge recall.

Introduction

Why memory matters in neural networks

Traditional neural networks process information in a feedforward manner, with limited ability to explicitly store and retrieve information. This creates challenges for tasks that require remembering facts, tracking state over long sequences, or reasoning over previously seen information.

Think of it like this

Imagine reading a book but only being able to remember the last sentence you read. That's similar to how standard neural networks operate. Memory networks give AI the ability to "take notes" and refer back to them later.

The Engram paper introduces a differentiable memory architecture that allows neural networks to learn what to store, when to store it, and how to retrieve relevant information when needed.

Key Concepts

Building blocks of memory networks

Memory Bank

A structured storage system that holds information in the form of key-value pairs, allowing efficient retrieval based on similarity.

Attention Mechanism

A soft addressing scheme that determines which memories are relevant to the current query, enabling selective retrieval.

Differentiable Memory

Memory that can be read and written using continuous operations, allowing gradients to flow through during training. This enables the network to learn optimal memory usage through backpropagation.

Architecture

How the components fit together

The Engram architecture consists of three main components that work together to enable memory-augmented neural computation:

Input Encoding

Convert input to embeddings

1

Memory Access

Read/write to memory bank

2

Reasoning

Process with retrieved context

3

Output

Generate final response

4
Neural Network with Memory
InputEncoderMemoryDecoderOutput

Click on a node to see signal propagation

Interactive visualization of a memory-augmented neural network. Click on nodes to see signal propagation.

Memory Mechanism

How reading and writing works

The memory mechanism uses attention to softly address memory locations. When reading, the network computes similarity scores between a query and all memory keys, then returns a weighted combination of memory values.

Key Insight

Unlike hard memory addresses in traditional computers, neural memory uses "soft" addressing based on content similarity. This makes it differentiable and learnable through gradient descent.

Mathematical Framework

The equations behind the magic

Let's break down the key equations that govern memory operations in Engram:

Attention Weights

This equation computes how much attention to give to each memory slot. Memories with keys similar to the query get higher weights.

Memory Read Operation

The read operation returns a weighted sum of all memory values, where weights are determined by attention scores.

Memory Write Operation

Writing to memory adds new information weighted by write strength. The erase and add mechanisms are combined for efficient updates.

Results

What the experiments show

The Engram model shows significant improvements on tasks requiring long-term memory and factual recall:

+23%
Question Answering
+18%
Language Modeling
+31%
Reasoning Tasks

Key Achievement

The model demonstrates emergent capabilities in multi-hop reasoning, where it can chain together multiple pieces of stored information to answer complex queries.

Conclusion

What this means for AI

Engram represents a significant step forward in creating AI systems that can effectively store, retrieve, and reason over information. By making memory operations differentiable, we can train end-to-end systems that learn optimal memory usage for specific tasks.

Future Directions

This work opens up possibilities for AI systems that can:
  • Maintain long-term context over extended conversations
  • Build and update knowledge bases automatically
  • Perform complex multi-step reasoning
  • Learn from experience and improve over time