Alzheimer’s Disease and Amyloid Plaques

Arthur was once a pillar of his community, a devoted leader at the local church whose sharp intellect and quiet dignity inspired those around him. Yet as the clouds of cognitive decline gradually descended, his world transformed into a maze of confusion and fear. Within the caregiving environment, Arthur occasionally uttered harsh words or resisted strongly when caregivers attempted to assist him with personal hygiene. To outside observers, such reactions might be labeled as defiant or aggressive behavior. However, through the lens of humanistic psychology, these actions can be understood as the final efforts of a self-attempt to protect its identity when the sense of personal control is being stripped away. Arthur is not merely a patient; he represents the profound complexity of cognitive aging, where biological loss intertwines with the resilient human struggle to preserve dignity and personhood.

Diagnostic Framework: From Dementia to Neurocognitive Disorder

In the era of the DSM-5-TR, the traditional term dementia has been replaced with the more scientifically precise concept of Major Neurocognitive Disorder. This shift is not merely semantic; rather, it reflects a deeper understanding of the specific cognitive domains affected while also removing the misconception that such conditions occur exclusively in older adults or are inevitably degenerative.

To establish a diagnosis, clinicians must identify significant cognitive decline from a previous level of functioning in at least one of six core cognitive domains: complex attention, executive function, learning and memory, language, perceptual, motor function, or social cognition. Importantly, these impairments must be severe enough to interfere with independence in everyday activities.

In cases such as Arthur’s, impairments in executive function often produce particularly devastating consequences. He may not only forget the names of loved ones but also lose the ability to plan or carry out complex, multi-step tasks. Another crucial clinical feature is that patients frequently demonstrate a lack of insight into their own condition. For this reason, assessing the severity of impairment cannot rely solely on patient self-report; it must be supplemented with objective observations from family members and standardized neuropsychological testing.

The Amyloid Hypothesis: Three Decades of Dominance and the Tremor of Scientific Scandal

Since Alois Alzheimer first identified dark plaques between neurons in the brains of patients in the early 1900s, medicine believed it had discovered a key clue to understanding the disease. By the 1990s, the Amyloid Cascade Hypothesis had become the dominant theory in neuroscience, proposing that the abnormal accumulation of beta-amyloid protein directly triggers neuronal death and the cognitive symptoms associated with dementia.

The dominance of this hypothesis shaped enormous research investment. Over the past three decades, billions of dollars have been poured into hundreds of clinical trials designed to eliminate or inhibit amyloid accumulation. Yet clinical reality has delivered a sobering result: nearly all amyloid-targeting interventions have failed. Even when modern antibody therapies successfully reduce amyloid plaque levels in the brain, patients’ cognitive functioning often shows little improvement. In some trials, cognitive decline has even progressed more rapidly compared with control groups.

Amid this impasse, a soluble amyloid oligomer known as Aβ*56 was introduced in a 2006 study by Sylvain Lesné, presented as a potential molecular smoking gun responsible for memory impairment. This discovery briefly revived hope that the amyloid hypothesis could still explain Alzheimer’s pathology. However, the field was shaken again in 2022 when a detailed investigation revealed evidence of manipulated Western blot image data in several of Lesné’s publications. The revelation cast serious doubt on the reliability of related findings and suggested that the scientific community may have spent decades pursuing a misleading direction, while the true mechanisms underlying Alzheimer’s disease might lie in alternative pathways that remain insufficiently explored.

When Love Becomes the Antidote: Psychosocial Interventions in Alzheimer’s Care

While biologists continue to investigate the molecular mechanisms of disease-related proteins, psychologist Tom Kitwood proposed a different perspective through the model of person-centered care. Kitwood argued that the deterioration experienced by individuals with dementia is not solely the result of neurological damage; it is often exacerbated by what he termed malignant social psychology, patterns of interaction that isolate patients, strip them of autonomy, and treat them as though they have lost their personhood.

Rather than focusing exclusively on deficits, this approach emphasizes meeting five fundamental psychosocial needs of individuals with dementia: comfort, attachment, inclusion, occupation, and identity. These needs converge around a central principle, love, unconditional acceptance, and deep empathy.

When these psychosocial needs are met, individuals with Alzheimer’s disease may gradually emerge from the shadows of fear, confusion, and anger. In doing so, they can regain moments of emotional harmony and peace, like returning home to a mist-filled garden of memories where their personhood is still recognized and protected until the very end.

Conclusion

Arthur’s story reminds us that Alzheimer’s disease is not merely a biological problem of proteins and plaques within the brain. It is also a profound human experience in which cognitive decline intertwines with an enduring effort to preserve identity and dignity. The ongoing debates surrounding the amyloid hypothesis illustrate that science is still searching for a comprehensive explanation of the disease’s underlying mechanisms. Yet even while biological answers remain incomplete, psychology offers a crucial insight: the way we treat individuals living with Alzheimer’s can profoundly shape the quality of their remaining life.

Person-centered care emphasizes that behind behaviors that may appear confusing or difficult lies a human being with fundamental psychological needs for connection, safety, and recognition. When families, caregivers, and communities approach Alzheimer’s disease with empathy rather than solely with diagnostic labels, they do more than reduce suffering, they help safeguard the remaining fragments of the individual’s personhood.

References

American Psychiatric Association. (2022). Diagnostic and statistical manual of mental disorders (5th ed., text rev.). https://doi.org/10.1176/appi.books.9780890425787

Barron, S. (2025). Psychopharmacology. In R. Biswas-Diener & E. Diener (Eds.), Noba textbook series: Psychology. Champaign, IL: DEF Publishers.

Kitwood, T. (1997). The experience of dementia. Aging & Mental Health, 1(1), 13–22.

Queen, T., & Smith, J. (2025). Aging. In R. Biswas-Diener & E. Diener (Eds.), Noba textbook series: Psychology. Champaign, IL: DEF Publishers.

Science.org. (2022). Faked Beta-Amyloid Data. What Does It Mean?

Vasquez, K. (2025). Neurocognitive disorders. Alverno College PSY 250.