Stroke's Impact: Altered Sensations And Touch After Effects

A stroke can cause a loss of touch sensation, known as somatosensory impairment, which occurs in 50-80% of stroke survivors. This loss of touch can be temporary or permanent, and can be accompanied by other symptoms such as numbness, prickling or tingling in the hands or feet, extreme sensitivity to touch, or a feeling of wearing gloves or socks when you're not.

The loss of touch sensation can be caused by damage to the brain, specifically the part of the brain that is connected to sensation receptors in the body. This can interfere with the way you detect things like pain, temperature or pressure, which can become potentially harmful to your health. For example, a reduced ability to detect vibration, touch and pressure increases your risk of injuries, including pressure ulcers.

There is a therapy called SENSe therapy which has been developed to help stroke survivors improve their sense of touch. It has been shown to be effective in a randomised controlled trial and has helped hundreds of stroke survivors improve their ability to undertake everyday tasks such as cooking, dressing, eating and driving.

A stroke can affect the part of the brain connected to sensation receptors in the body, which can interfere with the sense of touch

The sense of touch is important for physical, mental and emotional health. It helps us gather information about the world around us, and deepens our relationships with others. As we grow older, our ability to perceive touch can change or even fade. This is usually a normal part of aging, but a reduced sense of touch can sometimes mean something more serious is going on.

A stroke can happen when blood flow to the brain is blocked or when there's sudden bleeding in the brain. It is more common in older people, and the likelihood of having a stroke nearly doubles every decade after the age of 55. Strokes are more common in people with diabetes, hypertension and high cholesterol, as these conditions can affect the small arteries penetrating the brain.

There are a few other reasons why the sense of touch may change or fade as someone gets older. These include nutrient deficiencies, nerve damage from an injury, and diminished blood flow to the brain.

A loss of touch can be a symptom of a more serious issue, such as an underlying medical problem, diminished blood flow, a nutrient deficiency, or nerve damage from an injury

Underlying Medical Problem

A stroke is an underlying medical problem that can cause a loss of touch. A stroke occurs when blood flow to the brain is interrupted or reduced, preventing brain tissue from getting oxygen and nutrients. This can lead to brain damage and a loss of touch sensation.

Diminished Blood Flow

Diminished blood flow to the nerves can result in hypoesthesia, or a loss of sensation, in the affected area. This can be caused by various factors, including trauma from a blow or fall, metabolic abnormalities such as diabetes, compression that causes swelling, or pressure on a nerve.

Nutrient Deficiency

Nutrient deficiencies, particularly vitamin B-12 and magnesium deficiencies, can also lead to hypoesthesia. Vitamin B-12 is essential for maintaining healthy nerve cells, and a deficiency can cause numbness and tingling in the hands and feet. Similarly, magnesium plays a crucial role in nerve function, and a deficiency can result in numbness and tingling sensations.

Nerve Damage from Injury

Injuries that damage nerves can also lead to a loss of touch sensation. This includes trauma from a blow or fall, compression that causes swelling, repetitive movements that put pressure on a nerve, or needle injections near a nerve. Nerve damage can interrupt the signals between the brain and the affected area, resulting in a loss of touch sensation.

A loss of touch can put you at risk of injuries, including pressure ulcers, burns, and hypothermia

A stroke can cause a loss of touch sensation, which can put you at risk of injuries, including pressure ulcers, burns, and hypothermia.

Pressure Ulcers

Pressure ulcers, also known as pressure sores, occur when prolonged pressure on the skin hinders blood circulation and tissue turnover, leading to skin damage and necrosis. People with paralysis caused by a stroke are at an increased risk of developing pressure ulcers due to prolonged bed rest. Evidence-based nursing interventions, such as regular repositioning and skin care, can effectively prevent and reduce the incidence of pressure ulcers in stroke patients.

Burns

After a stroke, individuals may experience a loss of touch sensation, which can increase the risk of burn injuries. Impaired touch sensation can make it difficult to perceive temperature and pain accurately, leading to accidental burns. Additionally, the sensory loss can affect the individual's ability to interact with their environment and perform daily tasks, further increasing the risk of burn injuries.

Hypothermia

Hypothermia occurs when the body's core temperature drops below 35°C. Stroke patients, especially those with limited mobility, are at risk of hypothermia as they may be unable to protect themselves from cold environments. The natural response to cold temperatures includes physiological changes, such as shivering and increased metabolic rate, to generate heat. However, if these measures are insufficient, the body's temperature can drop dangerously low, leading to severe hypothermia. During severe hypothermia, the heart rate slows down and may become irregular, eventually leading to cardiac arrest.

Touch is important for physical, mental, and emotional health, and can deepen social connections

Touch is a basic human need with emotional, mental, and physical benefits. It is a key component in fostering deeper connections and emotional bonds, and has a wide range of benefits for both mental and physical health. Touch can reduce stress and promote feelings of relaxation by releasing oxytocin, a hormone that helps regulate our stress response. It also improves our immune system function by increasing levels of immune cells in the bloodstream. Touch can further reduce symptoms of anxiety, depression, and other mental health conditions.

Touch is important from the moment of birth, as babies need to cling, suckle, and rest on caregivers. This practice forms the bonds at the heart of our familial social structure and is a key tool for survival. Even as we age, touch remains critical to our social and emotional growth. For example, a study found that students were three times as likely to speak up in class after their teacher patted them in a friendly manner.

Touch can also inspire positive thinking and expand trust by releasing oxytocin, which helps inspire positive thinking and an optimistic outlook on the world. It can further reduce social anxiety and stress by increasing levels of dopamine and serotonin, two neurotransmitters that help regulate mood and relieve stress and anxiety.

Touch is known to improve the function of the immune system as well as reduce diseases associated with the heart and blood. For example, one study on women found that receiving more hugs from their partners led to lower heart rates and blood pressure.

Touch is an essential part of human relationships and has numerous benefits for mental and physical health. By incorporating healthy, consensual physical touch into our lives, we can experience a range of benefits that can improve our overall well-being.

Touch involves nerve endings in the skin perceiving things like pain, temperature, pressure, vibration, and body position

Touch is one of the principal sensations that can be elicited by sensory nerve endings in the skin. These nerve endings can also elicit pain, itch, warmth, and cold. The skin is supplied by both myelinated and unmyelinated branches of spinal nerves. Nerve branches enter the dermis from the subcutaneous fat and form both a superficial and a deep nerve plexus. Unmyelinated branches from either plexus terminate in nerve endings that may be simple or specialised. Terminals from a single axon may serve an area as broad as 1 cm^2 and overlap with nerve endings from other axons.

The skin has a high sensitivity to rapid mechanical stimulation, with positional movements of less than 1 μm detectable. Sensations of cold persist continuously when skin temperature is below 30°C, and sensations of warmth persist continuously when it is above 37°C. Changes in temperature of 0.03°C can be detected, especially if the skin temperature changes faster than 0.007°C/sec. Thermal sensitivity is highest on the face. At temperatures below 18°C and above 45°C, pain is produced. Pain may also be induced by pressure greater than 50 g/mm^2 and by disruption of skin. A number of chemicals injected into the skin may also elicit pain.

Specialised non-encapsulated nerve endings known as mucocutaneous endings are found in areas such as the lip, eyelid, tongue, gums, and glans penis. These are all areas of extreme sensitivity. Each mucocutaneous ending is a corpuscle composed of a network of unmyelinated nerve fibres surrounded by slightly condensed connective tissue but no properly formed capsule.

Temperature receptors in cutaneous nerve endings are thermostat molecules that induce thermoregulatory behaviours against thermal load. When skin temperature falls below a set-point, mammals experience "cold in the skin" and exhibit heat-seeking behaviours for error correction. A classical model of the sensory system states that thermoreceptors in skin nerve endings are sensors that transform temperature into the firing rate codes that are sent to the brain, where the codes are decoded as "cold" by a labelled line theory. However, temperature and "cold" are entirely different phenomena, so the view that the temperature code is transformed into "cold" (not temperature) is inconsistent.

Another model states that a thermostat exists in the brain based on the view that a skin thermoreceptor is a sensor. However, because animals have no knowledge of the principle of temperature measurement, the brain is unable to measure skin temperature with a thermometer calibrated based on a code table of each sensor in the skin. Thus, these old models cannot identify the thermostats.

A new model has been proposed in which temperature receptors in a nerve ending are molecules of the thermostats. When skin temperature falls below a set-point, these molecules as a whole induce impulses as command signals sent to the brain, where these impulses activate their target neurons for "cold" and heat-seeking behaviours for error correction.

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