Tangled Up

When Alzheimer’s disease enters a family, it rarely arrives with clarity. A forgotten appointment, a repeated story, a moment of sudden disorientation—small fractures that raise frightening questions about the future. Tangled Up: The History and Science of Alzheimer’s Disease is Professor Michael Hornberger’s clear, readable guide to what is happening inside the brain, why it happens, and what today’s science can do about it.

This is not a vague “brain health” overview. It is a lay-friendly journey through the neuroscience of Alzheimer’s disease: how the earliest brain changes build silently over years; how they translate into the symptoms families see; and why the story of Alzheimer’s is, at its heart, a story of proteins — amyloid plaques and tau tangles — becoming dangerously tangled up.

Hornberger begins where the modern field began: early 20th-Century Germany, where Alois Alzheimer met Auguste Deter, the first patient whose symptoms were linked to distinctive microscopic changes in the brain. Alongside Alzheimer stands the overlooked Oskar Fischer — another pioneer whose discovery deserves to be remembered. Part history, part scientific detective story, these opening chapters bring human voices and hard evidence together.

From there, Tangled Up moves into what most of us fear most: memory. Hornberger explains how episodic memory works—how the brain encodes, stores, and retrieves the events of our lives — and why Alzheimer’s disease disrupts access to recent memories first. You’ll understand why a loved one may seem to be “living in the past,” why the same questions return again and again, and why some everyday forgetfulness is normal ageing, while other patterns deserve attention.

One of the book’s most valuable contributions is its spotlight on an under-recognised early warning sign: spatial disorientation. Getting lost in familiar places, confusion in one’s own home, and a shrinking “mental map” can appear early and carry real-world risk. Tangled Up shows how the brain’s navigation systems work and why Alzheimer’s can unsettle them — offering a new lens for understanding behaviour and planning for safety without surrendering dignity.

At the core of the book is a deep dive into plaques and tangles. You’ll learn what amyloid and tau normally do, how they go awry, how they spread through the brain,...