Friday, January 20, 2017

Forgetfulness and Memory Loss at Work

Forgetfulness and Memory Loss

Forgetfulness or failure to remember information, is a common complaint. All of us have at some time or the other forgotten to make that important call, to pick up some items from the store, an anniversary or birthday, or a colleague’s name. Students forget what they have “learnt” during exams. We often can’t remember where we have left our car keys, our wallet or that important document. Is it normal? And more importantly; when do we need to seek help?

Forgetfulness or memory loss and difficulty concentrating are common symptoms of mental health disorders. This is specially so in depression, anxiety disorders, ADHD (Attention Deficit Hyperactivity Disorder), and dementias as shown in the examples below.
A young working professional seeks help for increased forgetfulness and poor ability to focus at work. Further probing reveals decreased interest in doing things at work and home. She is also irritable, depressed and her sleep is disturbed. These symptoms of low mood can exist in the background of memory loss and problems with focus.
A student during exams has high anxiety causing memory loss. She cannot recall the answer to a certain question. She gets nervous. This causes her to make mistakes in the next question. She tends to panic; fail to recall what she studied. This vicious cycle is common in anxiety disorders and can manifest as problems with concentration, memory and forgetfulness.
An older person does not just forget the name of his neighbour (something that may happen to any of us); but also who she is. He has problems using money, and with shopping. Difficulties at work manifest towards the end of the career. Dementias affect the aged; cause memory loss and affect the context of the memory. 
A young professional person has problems organising and completing projects at work. There may be a history of attention and academic problems in school. Working memory gaps are common in this group. ADHD is a common cause of this problem in adults.

Memory Processing in the Brain

To understand further, it helps to know in brief how memory works. It is a 3 stage process
Encoding
The stage when sounds, images and other sensations are given meaning is called encoding. Sensations are coded electrically for access by other brain areas. (We hear a catchy song from a new movie).
Storage
The process of association or tagging the input with other bits of data to make it persist. The song thus gets stored in our long term memory. Initially, the song remains for a very short while. At this point it is in our working or short term memory. It is encoded. However, we forget the song as the next scene unfolds on screen. The song is repeated at the end of the movie; someone hums the song as we leave the hall. The visuals of the song, and the feelings evoked, the fact that it was a famous actor, then reinforce the memory and makes it persist.
Retrieval
When we need to use this stored data, the brain fishes it out from its long term memory. The more the associations or tags we formed earlier, the more easily the brain can access the information.
Problems in memory can therefore occur at any of these stages. Many of these occur at the stage of encoding because we are simply not paying attention; and many other distractions are vying for our focus at the same time. (e.g checking our FB messages while studying). The brain does not multi-task, it can only do one thing at a time.

Repetition, rehearsal and organisation help in fixing and storage of long term memory. The more widespread and elaborate the connections, and the more data available about an input, the more the connections formed by the brain, and the easier it is for the brain to retrieve the information when required. Many cases of forgetting are due to retrieval failures. The information is there in long term memory but we are unable to access it. This is why we can recall certain things at a later date.
Depression affects memory in many ways. Being unable to concentrate is a symptom of depression. Repeated depressive thoughts also block the learning process through distraction. This affects the stage of encoding. Disturbed sleep which is a common symptom in depression hampers fixing into long term memory.
Forgetfulness is common in ADHD of adults. ADHD lowers the power to focus. The person is easily distracted. The attention span is reduced. This impairs short term or working memory. ADHD persists in up to 40% of aduts.
Anxiety gives rise to pointless thoughts (“my father will be so angry if I don't crack this exam”) which frustrates attempts to retrieve the matter learned. The anxiety provoking thoughts distract from the text which is being studied and impedes the  encoding process.
In dementia there is destruction and loss of brain cells. Dementia blocks all stages of the memory and learning process. The process is not reversible.

Forgetfulness and Memory Loss – when to seek help?

  • When it affects our work, or the quality of our work
  • When the failure to learn and recall affects our daily activities and functioning
  • When there are also problems including sleep, appetite, inter-personal or behaviour changes.
  • When it is strange - leaving keys in the fridge 
  • When it can harm - often leaving cooking burner on, leaving doors unlocked at night
In normal forgetfulness, the person may recall the memory when some cues are given. The memories were encoded, they just needed some reminder to access them. In clinical disorders resulting in memory loss the memories were never laid down in the first place, or the storage structures in the brain are destroyed. Access to these memories may not be possible. 
References
  1. Brydges CR, Ozolnieks KL, Roberts G. Working memory - not processing speed - mediates fluid intelligence deficits associated with attention deficit/hyperactivity disorder symptoms. J Neuropsychol. 2015 Dec 31. doi: 10.1111/jnp.12096. [Epub ahead of print]

Thursday, September 27, 2012

Alzheimer's caregiver techniques


world alzheimers day 2012

Caregivers living with persons having Alzheimer's Disease face specific problem behaviours. These behavioural problems result from memory loss that is the hallmark symptom of Alzheimer's. We have previously discussed resources giving hope for dementia caregivers. Caregiver do's and dont's for mental illnesses in general have also been highlighted. Living with Alzheimer's Disease is the theme for World Alzheimer's Day 2012. In this post we specify methods to help caregivers living with persons having Alzheimer's handle problems related to memory loss and reduce the burden of  care at home.

Caregiver techniques for Alzheimer's

  1. Regular routine enables basic activities of daily living for a longer period of time. Make a visual time-table and regularly remind the person with Alzheimers to consult it so it becomes a habit.
  2. Keep large clocks in each room and remind them of the time at every opportunity.
  3. A personalised calendar with large figures helps plan and anticipate potentially confusing events such as a festival or travel.
  4. A room with a window is great for orientation. Natural daylight and dark phases maintain the sleep-wake cycle.
  5. Greet at every new meeting with date and time. The date is particularly difficult for a person with Alzheimer's to learn - it changes every day -  hence the disorientation. Repetition will keep the person with Alzheimers disease current with the month and year for longer.
  6. Keep familiar objects like photos, phone, books, and decorative pieces in the same place. People with Alzheimer's often have to move from one set of caregivers to another. Placing these objects in the same general positions helps them to avoid confusion and  anxiety.
  7. Photographs are important visual memory pegs. Two or three frames with photographs of the caregiver families and old friends reassures the person with Alzheimer's disease and facilitates their smooth transition between caregivers.
  8. An identity card is essential for every person with  Alzheimer's. It must contain an address and an emergency contact number. It should be worn at all times, even inside the  house. Your loved one can wander out of an open door and not  be able to find her way back. Reinforce and rehearse showing or consulting the identity card on being asked for address or phone number.
  9. Encourage and let them do the  things they can. Don't take over every activity or your caregiver burden will increase. Prompt them when they hesitate or take time. Help them in those activities they are unable to do.
Anti-dementia drugs delay nursing home admissions for upto a year. To make home this stay meaningful and to reduce the burden of care these methods need to be used by caregivers living with Alzheimer's Disease patients.

Friday, August 31, 2012

Alzheimers disease - mild cognitive impairment countdown

alzheimers timeline

Alzheimers dementia is usually diagnosed when memory loss and behavioural symptoms are readily apparent to their caregivers. At this stage the primary concern is to slow further deterioration. Caregivers at the clinic have often wished they could have looked into the future. Many have a history of Alzheimers disease in their elderly and wondered whether there was an earlier way of knowing. New knowledge gives us hope in this direction.

Alzheimers disease before memory loss

We now have the beginnings of a time line in the countdown to dementia. It is now possible to trace the beginnings of Alzheimers Dementia up to 20 years before its manifestation with memory loss and impaired function.

20

Beta-amyloid levels in the cerebrospinal fluid (CSF)  begin to drop 20 years before the onset of dementia. Alzheimer's Disease is characterized by toxic deposition of specific beta-amyloid (Aβ1-42) plaques around the brain cells. In normal aging beta-amyloid continues to increase in the brain fluid. However, in Alzheimers Dementia brain fluid beta-amyloid is markedly reduced.This is due to reduce clearance of beta-amyloid from the brain to the blood and CSF, as well as increased beta-amyloid plaque deposition in the brain.

15

15 years before dementia onset, beta-amyloid deposits can be detected by amyloid imaging PET scans. The best known amyloid PET tracer is Pittsburgh Compound-B (PIB). PIB retention is found in over 90% clinically diagnosed AD patients.
Tau protein accumulation inside the brain cells (neurons) is the second hallmark of Alzheimer's disease.  Microtuble associated protein tau (MAPT) in the brain fluid (CSF) increases with age. In Alzheimer's disease tau levels are markedly increased and reflects damage to the neurons and axons (brain cells). High CSF tau level differentiates mild cognitive impairment (MCI) from that which progresses to Alzheimer's disease.
Shrinkage or atrophy of the brain becomes detectable by MRI. This atrophy is visible in brain structures that are essential for the conscious memory of facts and events. These areas are located in the brain’s medial temporal lobe. This shrinkage is apparent on using a visual rating system which also measures its severity. The more extensive the brain atrophy, the more advanced the clinical stage of Alzheimer’s disease.

10

PET Scan (FDG-PET) changes in the way the brain uses glucose are apparent 10 years before dementia. These PET scan changes correlate with progression of Alzheimers disease.
Episodic memory loss begins at this stage. Episodic memory loss is the inability to learn new information or to recall previously learned information. It manifests as forgetting of recent events and conversations, repetitive questions, repetitive retelling of stories, forgetting the date, forgetting appointments, misplacing objects, losing valuables, and forgetting that food is cooking on the stove. The formation of new episodic memories requires intact medial temporal lobes of the brain; these are progressively destroyed in Alzheimers disease.

5

Mild cognitive impairment (MCI) deveelops 5 years before dementia. People with mild cognitive impairment have problems with thinking and memory loss. Mild cognitive impairment does not interfere with everyday activities. Persons with mild cognitive impairment are often aware of their forgetfulness.
Preventive therapies for Alzheimers disease (AD) require the development of biomarkers that are sensitive to subtle brain changes occurring in the preclinical stage of the disease. Early diagnostics is necessary to identify and treat at risk individuals before irreversible neuronal loss occurs.
Sources
  1. Bateman R. The dominantly inherited Alzheimer's network trials: an opportunity to prevent Alzheimer's disease. Program and abstracts of the Alzheimer's Association International Conference 2012; July 14-19, 2012; Vancouver, British Columbia, Canada. Featured research session F3-04
  2. Christian Humpel. Identifying and validating biomarkers for Alzheimer's disease. Trends Biotechnol. 2011 January; 29(1): 26–32. doi: 10.1016/j.tibtech.2010.09.007
  3. Duara R, Loewenstein DA, Potter E, Appel J, Greig MT, Urs R, Shen Q, Raj A, Small B, Barker W, Schofield E, Wu Y, Potter H. Medial temporal lobe atrophy on MRI scans and the diagnosis of Alzheimer disease. Neurology. 2008 Dec 9;71(24):1986-92.
  4. Mosconi L, Berti V, Glodzik L, Pupi A, De Santi S, de Leon MJ. Pre-clinical detection of Alzheimers disease using FDG-PET, with or without amyloid imaging. J Alzheimers Dis. 2010;20(3):843-54.