Overview

Memory is part of our existence as human beings. It shapes us, impacts our relationships, and allows us to engage with the world. Memory loss can be extremely disturbing, whether temporary or as part of a chronic process.

There are some common myths and misconceptions about memory loss, which tend to lead to stigmatisation and anxiety. The majority of people wrongly believe, for instance, that all memory loss is due to traumatic brain injury or dementia.

Knowledge that Transient Global Amnesia (TGA) is a reversible syndrome and is benign can minimise anxiety.

Understanding Transient Global Amnesia (TGA)

Transient global amnesia is an acute, transient episode of memory loss which occurs in isolation - i.e., it is not associated with an underlying neurological disease.

By definition, it is a benign condition, impairing short-term memory but not long-term memory, and does not impair the individual's ability to recognise themselves or others.

Transient global amnesia is a relatively rare condition that is seen in fewer than 1% of the population in any given year. It is most frequently seen in middle-aged and older populations.¹

Most people with TGA present with the following symptoms:

• Abrupt onset of memory loss: TGA presents with an abrupt onset of memory loss, and the individual describes being in a "blank" state
• Inability to store new memories: During the episode, the individual is unable to remember new experiences or retain information, which may continue from a few minutes to 24 hours 
• Retained awareness of identity: TGA does not disrupt the person's awareness of him/herself; they are aware of where they are and who they are

TGA attacks are usually of short duration and resolve completely. Heightened emotional experiences, exercise, and stressful events have been reported to precipitate TGA attacks.²

Distinguishing TGA from other amnesic disorders

Memory loss can happen in more than one way and can be due to numerous underlying disorders. It is essential to be aware of the distinguishing characteristics of such disorders so that appropriate care and support can be provided.

Dementia

Dementia is an overarching term for neurologic conditions that increasingly affect cognitive function and are of severity sufficient to impede daily activity. Alzheimer's disease is the most prevalent type of dementia.

Key features:

• Dementia is a progressive condition with worsening symptoms that accumulate over time. TGA is not a progressive condition and is temporary, with individuals reverting to their pre-event level of cognitive functioning after the incident
• Cognitive function becomes worse as dementia progresses and involves language, judgment, and reasoning functions. TGA is not typically found to impair any cognitive function with the exception of the temporary impairment of memory³

Stroke

Stroke occurs when the brain is deprived of blood supply due to a blockage (ischemic stroke) or haemorrhage (hemorrhagic stroke) and does not receive a sufficient amount of oxygen.

Key differences

Memory loss as a result of stroke is immediate and is usually coupled with signs that you can identify using the FAST test:

• Face weakness
• Arm weakness
• Speech difficulties
• Time to call the emergency services

Unlike TGA, the impact of a stroke can lead to permanent damage to the brain and can be life-threatening, depending on the size and location of the brain injury.⁴

Transient Ischemic Attacks (TIAs)

TIAs or "mini-strokes" are a brief interruption of blood flow to the brain, leading to stroke-like symptoms that recover in 24 hours.

Key features:

• TGA is primarily an amnestic disorder, whereas TIAs can have a myriad of neurological deficits, including weakness, difficulty with speech, dizziness, or vision loss
• TIAs are often a sign of a greater likelihood of a “full-blown” stroke, while TGA is an innocuous syndrome and does not predict other complications⁵
• Individuals who experience a TIA must receive immediate medical care to minimise the risk of future strokes

Other causes of amnesia

Aside from TGA, dementia, and stroke, there are many other causes of amnesia, including:

• Traumatic brain injury: Physical trauma can result in significant loss of short- and long-term memory, as well as other essential mental functions, and even impulsivity and personality changes
• Substance misuse or withdrawal: Some drugs can influence memory performance. This is also known as substance-induced amnesia
• Psychological factors: Trauma or stress may cause dissociative amnesia and cause loss of memory regarding some experience or event⁶

Diagnosis and treatment

A correct diagnosis is necessary in determining the correct line of action. Medical physicians typically assess individuals through neurological examination and cognitive tests.

Brain imaging via CT scans and MRI scans is one of the very important tools to employ in TGA's differentiation from other conditions that may potentially be the underlying condition, like tumour or stroke. With them, doctors can exclude lethal neurological disease.⁷

Transient Global Amnesia (TGA) will resolve on its own without intervention. The approach during an attack is to let the individual settle and ensure there is no underlying condition for memory loss. Physicians will attempt to exclude serious diseases such as stroke or neurological disorders by observation and diagnostic examination.

For dementia, interventions are sophisticated and tend to be medication for loss avoidance of mental faculties and restoration of mental functioning. Cognitive therapy and supportive therapy are extremely useful in alleviation quality-of-life deficits and enabling the individual to live as independently as feasible. Intervention aims at enabling the individual and his or her carers or family members to manage the issues of a chronic neurological condition.

For TIAs and stroke, immediate medical treatment is needed to reduce damage and prevent further injury. Based on the stroke, treatments include medications that dissolve blood clots, surgery, or other interventions to restore the flow of blood to the brain.

Following blockage treatment, rehabilitation, i.e., physical therapy, speech therapy, etc., is typically the follow-up treatment. Life-saving interventions are sometimes necessary in severe cases, based on the location and severity of the stroke. Rehabilitation is designed to regain as much function as the individual will have and to deal with long-term consequences.⁸

Emotional impact of amnesic conditions

People with TGA describe their attacks as bewildering and terrifying. They may know that they cannot remember what occurred some time ago, but know who they are. Not being in control of the attack is scary, although the person knows that the attack will resolve. Because TGA also interferes with memory for new information, it may be difficult to keep from getting anxious. Other people should remain calm with the victim of TGA and offer any reassurance they can, reassuring them that everything will soon be back to normal.

In contrast, people experiencing dementia or stroke are susceptible to issues with chronic loss of cognitive function and loss. The relatives and carers also feel the emotional toll of managing and taking care of the loved ones with such illnesses. There are support groups available for family members and carers of people with dementia, stroke, and other conditions.

Creating a supportive environment around individuals dealing with memory loss, either temporary or permanent, is critical. Family and friends are to offer emotional support and reassurance. They can guide them to feelings of acceptance and identification with referral to professional consultation to eliminate anxiety and hasten the recovery process. 

Coping mechanisms

Care and coping strategies can soothe people experiencing TGA episodes, as well as other memory conditions:

• Memory journal: Writing can help people to record their experiences and remember things
• Establishing routines: Developing a routine daily schedule can be comforting and enhance memory recall
• Support-seeking: Attending therapy or a support group generates a sense of belonging and open communication about memory loss

If you or a loved one is experiencing memory loss, it's crucial to ask for help. The knowledge that you are not alone and assistance can be found may be some comfort at times of despair.

Summary

Understanding that Transient Global Amnesia (TGA) is different from other types of memory loss is crucial in reducing fear and giving proper support to those who are going through it.

TGA is a benign, temporary condition where individuals forget their recent memories and are unable to form new ones. They can recognise themselves and others. The attacks last from a few hours to an entire day and typically go away on their own with no lasting effects.

TGA differs from conditions like dementia, stroke, or TIAs:

• Dementia causes progressive loss of memory and cognitive ability, affecting a person's lifestyle and worsening with time
• Stroke causes sudden and permanent brain damage and memory loss, with other symptoms like weakness or slurred speech
• TIAs, or "mini-strokes," have symptoms similar to those of a stroke but clear within 24 hours and can suggest future stroke risk
• Other forms of memory loss, such as traumatic brain injury, drug abuse, and psychological trauma, may affect memory but are caused by and treated differently

It is startling and disorienting to have an experience of memory loss, even a temporary one such as TGA. It is essential to give emotional support to reduce anxiety.

In chronic conditions like dementia or after a stroke, the emotional effect is longer-lasting and is experienced not only by the individual but also by the caregivers.

Having a memory book or establishing a routine can help daytime functioning and reduce stress.

Group counselling or therapeutic counselling can help make people less lonely and provide you with helpful skills to manage memory loss.

Since TGA is a harmless and reversible condition, awareness about it can reduce unnecessary worry, and awareness about the symptoms of more serious conditions can initiate proper treatment. Increased awareness about memory loss and coping strategies you can use can help make distressing situations easier to navigate for people experiencing TGA and their loved ones.