Psychology Wiki
Register
Advertisement

Assessment | Biopsychology | Comparative | Cognitive | Developmental | Language | Individual differences | Personality | Philosophy | Social |
Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology |

Cognitive Psychology: Attention · Decision making · Learning · Judgement · Memory · Motivation · Perception · Reasoning · Thinking  - Cognitive processes Cognition - Outline Index


In Alzheimer’s disease and olfaction can be impaired. Indeed this is so characteristic that Solomon et al (1998) [1] suggested that the Pocket Smell Test could be used as a diagnostic tool to distinguish between the condition and major depression.


Hyposmia - decreased ability to smell[]

Doty[2] reviewed 13 studies investigating olfaction in Alzheimer's patients compared to age-matched controls and identified that the majority of studies found significantly decreased function in Alzheimer's patients.

Nordin and Murphy[3] also documented impaired olfaction in patients with possible Alzheimer's.

Morgan et al.[4] reported that odor identification tasks could be useful in diagnosing Alzheimer's and that possible language deficits in this group were not responsible for the difficulties in smell identification.


Anosmia - lack of ability to smell[]

For some people wih Alzeimers the sense of smell can disappear completely.[5]


Neuroscience[]

A postmortem study by Reyes et al (1993) [6] has demonstrated increased numbers of neurofibrillary tangles and neuritic plaques in the olfactory cortex of Alzheimer's patients versus age-matched control subjects. DotyCite error: Invalid <ref> tag; refs with no name must have content has suggested that the magnitude of the olfactory deficit parallels the progression and severity of the Alzheimer's process.


References[]

  1. Solomon, Gary S.; Petrie, William M. Hart, James ; Brackin, Henry B. Jr. (1998). Olfactory Dysfunction Discriminates Alzheimer's Dementia From Major Depression. The Journal of Neuropsychiatry and Clinical Neurosciences ;10:64-67.
  2. Doty RL: Olfactory dysfunction in neurodegenerative disorders, in Smell and Taste in Health and Disease, edited by Getchell TV. New York, Raven, 1991, pp 735—751
  3. Nordin S, Murphy C: Impaired sensory and cognitive olfactory function in questionable Alzheimer's disease. Neuropsychology 1996; 10:113—119
  4. Morgan CD, Nordin S, Murphy C: Odor identification as an early marker for Alzheimer's disease: impact of lexical functioning and detection sensitivity. J Clin Exp Neuropsychol 1995; 17:793—803
  5. Solomon GS (1994). Anosmia in Alzheimer's disease. Percept Mot Skills ; 79:1249—1250,
  6. Reyes PF, Deems DA, Suarez MG: (1993). Olfactory-related changes in Alzheimer's disease: a quantitative neuropathological study. Brain Research Bulletin  ; 32:1—5

[[category:Olfactory perception]

Advertisement