Published online by Cambridge University Press: 30 November 2019
Unlike the degenerative disorders that cause dementias, which stem from a modest number of aberrant processes, aging-related cognitive changes reflect a host of mechanisms. These include mechanisms associated with a person’s condition, e.g., drugs, pain, depression, and sleep disorders. They include mechanistic changes linked to the aging process, e.g., enhanced neural network noise, increased neighborhood density, age of acquisition effects, degraded selective engagement of neural networks, alteration of the balance between volitional and reactive intention and attention, declines in neurotransmitter function, and brain ontogenesis over the life span. They include changes best characterized as senescent physiology and best demonstrated in decline in functions essential to episodic memory formation related to impaired encoding in the hippocampal cornu amonis (CA) fields and slowed neurogenesis in the hippocampal dentate gyrus. Finally, they include processes best characterized as senescent pathology, the best understood being degradation of myelin and associated reduction of central conduction velocities and slowing of processing speed. No longer should cognitive changes associated with aging be viewed as a simple manifestation of a unitary aging process. The large number of mechanisms at play and their complexity offer many opportunities for therapeutic intervention.
To save this book to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.