The symptoms of dementia can differ depending on the cause of the dementia and the stage of the disease. Although late-stage signs and symptoms may be similar across etiologies, early stage symptoms can vary considerably. For example, individuals with FTD and Huntington's disease experience behavior changes and depression; those with primary progressive aphasia experience gradual loss of language function but relatively well-preserved memory; and individuals with Binswanger's disease (a type of vascular dementia) experience stroke-related neurological symptoms, including dysarthria and dysphagia (Hegde, 2006).
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In general, individuals with dementia experience a gradual loss of memory and other cognitive functions. As the disease progresses, early symptoms intensify, eventually affecting the ability to communicate effectively and function independently.
Listed below are examples of common signs and symptoms of dementia. Not every person with dementia will experience all of these symptoms, and symptoms can vary depending on the underlying neuropathology and individual differences.
- Easily distracted
- Difficulty attending, unless input is restricted/simplified
- Decreased information-processing speed—thinking/processing takes longer than usual
- Episodic memory deficits, including difficulty remembering autobiographical events, situations, and experiences
- Short-term/working memory deficits—rapid forgetting of information recently seen or heard
- Difficulty recalling names of family and friends
- Difficulty acquiring and remembering new information (e.g., appointments or events, new routines) without specific supports or strategies
- Difficulty setting goals and planning, including reliance on others to plan activities and/or make decisions
- Poor judgment and impaired reasoning and problem-solving abilities (e.g., making decisions without regard to safety)
- Difficulty multitasking and handling complex tasks—need to focus on one task at a time
- Difficulty responding to feedback
- Poor self-monitoring and ability to correct own errors
- Lack of inhibition
- Lack of mental flexibility
- Difficulty completing previously familiar activities or navigating in familiar environments
- Inability to recognize familiar people, common objects, sounds, and so forth
- Inability to find objects in direct view, independent of visual acuity
- Other visuo-perceptual difficulties, such as trouble with depth perception and sensitivity to light
- Less concise (empty) discourse with fewer ideas
- Economy of utterances (using fewer words) and stereotypy of speech
- Repetitious/perseverative language (e.g., asking the same question repeatedly)
- Word-finding difficulties signaled by long latencies, paraphasias, and word substitutions
- In people who are bilingual, errors in selecting and maintaining appropriate language during conversation (Friedland & Miller, 1999)
- In people who are bilingual, regression to primary language (Kokorelias, Ryan, & Elliot, 2017; Mendez, Perryman, Pontón, & Cummings, 1990)
- Tangential language
- Grammatical errors, including omission or incorrect use of articles, prepositions, auxiliary verbs, and so forth
- Use of jargon and loss of meaningful speech
- Impaired ability to compose meaningful written language
- Difficulty following and maintaining conversation
- Language comprehension deficits
- Difficulty following multistep commands
- Reading comprehension difficulties with complex materials
- Anger and aggression
- Anxiety or agitation
- Forgetfulness and confusion
- Repetitive actions
- New suspicions
- Wandering and getting lost
- Trouble sleeping
- Mood fluctuations, including agitation and crying
- Negative reaction to questioning
- Loss of initiative and motivation
Behavioral and psychosocial symptoms are common in dementia (see, e.g., Müller-Spahn, 2003). Responsive behaviors—a subset of these symptoms—are thought to be expressions of unmet needs (e.g., pain), responses to the environment (e.g., overcrowding), expressions of psychosocial needs (e.g., depression), and responses to caregivers and other individuals.
Behavioral and psychosocial changes can lead to frustration and misunderstanding between the individual with dementia and his or her caregiver. Since these reactions are often forms of communication, it is important for caregivers to consider why the behavior is occurring and to explore ways to facilitate better communication (e.g., react differently, be understanding, modify/adapt the environment, and focus on a different activity).
Behaviors: How To Respond When Dementia Causes Unpredictable Behaviors [PDF] from the Alzheimer’s Association for more information.
The cognitive changes associated with dementia can have a significant impact on day-to-day communication. For example, a decline in memory, attention, executive functioning, and/or language processing can make it difficult to follow and participate in conversation.
- process information more slowly;
- lose track of the topic;
- miss the point; and
- repeat information.
With more significant cognitive decline,
- they may become disoriented to time and place;
- they may have difficulty remembering recent events;
- their verbal output may be reduced and less substantive; and
- their ability to express thoughts, wants, and needs may be affected.
Swallowing function changes as we age. These changes may be more pronounced in individuals with dementia, and swallowing difficulties may appear sooner (Groher, 2015). Overall, 13%–57% of individuals with dementia have swallowing impairment (Alagiakrishnan, Bhanji, & Kurian, 2013). Rates of swallowing impairment for individuals with dementia in long-term care may be as high as 53%–60% (Alagiakrishnan et al., 2013; Park et al., 2013).
Difficulties are not limited to swallowing dysfunction—cognitive and behavioral changes associated with dementia can also have an impact on eating. Early on, individuals may have difficulty shopping for groceries and planning and preparing meals independently (Arrighi, Gélinas, McLaughlin, Buchanan, & Gauthier, 2013; Hickey, Cleary, Coulter, & Bourgeois, 2018). They may forget to eat, initiate eating less often, or have difficulty determining the need to eat (Arrighi et al., 2013; Bourgeois & Hickey, 2009). As the disease progresses, they may become more distracted during mealtime or have difficulty self-feeding, recognizing foods, or using various eating utensils (Aselage & Amella, 2011; Bourgeois & Hickey, 2009; Lee & Song, 2015; Rogus-Pulia, Malandraki, Johnson, & Robbins, 2015; Wu & Lin, 2015).
Eating and swallowing difficulties may place an individual at greater risk for choking and aspiration pneumonia (Bourgeois & Hickey, 2009) and may eventually result in malnutrition, dehydration, and weight loss (Hanson, Ersek, Lin, & Carey, 2013; Jensen, Compher, Sullivan, & Mullin, 2013).