During the pandemic, a lost sense of smell was quickly identified as one of the key symptoms of COVID. Nearly four years later, one in five people in the UK is living with a decreased or distorted sense of smell, and one in twenty have anosmia – the total loss of the ability to perceive any odours at all. Smell training is one of the few treatment options for recovering a lost sense of smell – but can we make it more effective?

Smell training is a therapy that is recommended by experts for recovering a lost sense of smell. It is a simple process that involves sniffing a set of different odours – usually essential oils, or herbs and spices – every day.

The olfactory system has a unique ability to regenerate sensory neurons (nerve cells). So, just like physiotherapy where exercise helps to restore movement and function following an injury, repeated exposure to odours helps to recover the sense of smell following an infection, or other cause of smell loss (for example, traumatic head injury).

Several studies have demonstrated the effectiveness of smell training under laboratory conditions. But recent findings have suggested that the real-world results might be disappointing.

One reason for this is that smell training is a long-term therapy. It can take months before patients detect anything, and some people may not get any benefit at all.

In one study, researchers found that after three months of smell training, participation dropped to 88%, and further declined to 56% after six months. The reason given was that these people did not feel as though they noticed any improvement in their ability to smell.

Cross-modal associations

To remedy this, researchers are now investigating how smell training can be improved. One interesting idea is that information from our other senses, or “cross-modal associations”, can be applied to smell training to promote odour perception and improve the results.

Cross-modal associations are described as the tendency for sensory cues from different sensory systems to be matched. For example, brightness tends to be associated with loudness. Pitch is related to size. Colours are linked to temperature, and softness is matched with round shapes, while spiky shapes feel more rough. In previous studies, these associations have been shown to have a considerable influence on how sensory information is processed. Especially when it comes to olfaction.

Recent research has shown that the sense of smell is influenced by a combination of different sensory inputs – not just odours. Sensory cues such as colour, shape, and pitch are believed to play a role in the ability to correctly identify and name odours, and can influence perceptions of odour pleasantness and intensity.

In one study, participants were asked to complete a test that measured their ability to discriminate between different odours while they were presented with the colour red or yellow, an outline drawing of a strawberry or a lemon, or a combination of these colours and shapes. The results suggested that corresponding odour and colour associations (for example, the colour red and strawberry) were linked to increased olfactory performance compared with odours and colours that were not associated (for example, the colour yellow and strawberry).

While projects focusing on harnessing these cross-modal associations to improve treatments for smell loss are underway, research has already started to deliver some promising results.

In a recent study that aimed to investigate whether the effects of smell training could be improved with the addition of cross-modal associations, participants watched a guidance video containing sounds that matched the odours that they were training with. The results suggest that cross-modal interactions plus smell training improved olfactory function compared to smell training alone.

The results reported in recent studies have been promising and offer new insights into the field of olfactory science. It is hoped that this will soon lead to the development of more effective treatment options for smell recovery.

In the meantime, smell training is one of the best things you can do for a lost sense of smell, so patients are encouraged to stick with it so that they give themselves the best chance at recovery.

Emily Spencer, PhD Candidate, Olfaction, Edinburgh Napier University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

For most people, the daily or near-daily ritual of having a bowel motion is not something we give a great deal of thought to. But for some people, the need to do a “number two” in a public toilet or at work can be beset with significant stress and anxiety.

In recognition of the discomfort people may feel around passing a bowel motion at work, the Queensland Department of Health recently launched a social media campaign with the message “It’s okay to poo at work”.

The campaign has gained significant traction on Instagram and Facebook. It has been praised by health and marketing experts for its humorous handling of a taboo topic.

A colourful Instagram post is accompanied by a caption warning of the health risks of “holding it in”, including haemorrhoids and other gastrointestinal problems. The caption also notes:

If you find it extremely difficult to poo around other people, you might have parcopresis.

What is parcopresis?

Parcopresis, sometimes called “shy bowel”, occurs when people experience a difficulty or inability to poo in public toilets due to fear of perceived scrutiny by others.

People with parcopresis may find it difficult to go to the toilet in public places such as shopping centres, restaurants, at work or at school, or even at home when friends or family are around.

They may fear being judged by others about unpleasant smells or sounds when they have a bowel motion, or how long they take to go, for example.

Living with a gastrointestinal condition (at least four in ten Australians do) may contribute to parcopresis due to anxiety about the need to use a toilet frequently, and perceived judgment from others when doing so. Other factors, such as past negative experiences or accessibility challenges, may also play a role.

For sufferers, anxiety can present in the form of a faster heart rate, rapid breathing, sweating, muscle tension, blushing, nausea, trembling, or a combination of these symptoms. They may experience ongoing worry about situations where they may need to use a public toilet.

Living with parcopresis can affect multiple domains of life and quality of life overall. For example, sufferers may have difficulties relating to employment, relationships and social life. They might avoid travelling or attending certain events because of their symptoms.

How common is parcopresis?

We don’t really know how common parcopresis is, partly due to the difficulty of evaluating this behaviour. It’s not necessarily easy or appropriate to follow people around to track whether they use or avoid public toilets (and their reasons if they do). Also, observing individual bathroom activities may alter the person’s behaviour.

I conducted a study to try to better understand how common parcopresis is. The study involved 714 university students. I asked participants to respond to a series of vignettes, or scenarios.

In each vignette participants were advised they were at a local shopping centre and they needed to have a bowel motion. In the vignettes, the bathrooms (which had been recently cleaned) had configurations of either two or three toilet stalls. Each vignette differed by the configuration of stalls available.

The rate of avoidance was just over 14% overall. But participants were more likely to avoid using the toilet when the other stalls were occupied.

Around 10% avoided going when all toilets were available. This rose to around 25% when only the middle of three toilets was available. Men were significantly less likely to avoid going than women across all vignettes.

For those who avoided the toilet, many either said they would go home to poo, use an available disabled toilet, or come back when the bathroom was empty.

Parcopresis at work

In occupational settings, the rates of anxiety about using shared bathrooms may well be higher for a few reasons.

For example, people may feel more self-conscious about their bodily functions being heard or noticed by colleagues, compared to strangers in a public toilet.

People may also experience guilt, shame and fear about being judged by colleagues or supervisors if they need to make extended or frequent visits to the bathroom. This may particularly apply to people with a gastrointestinal condition.

Reducing restroom anxiety

Using a public toilet can understandably cause some anxiety or be unpleasant. But for a small minority of people it can be a real problem, causing severe distress and affecting their ability to engage in activities of daily living.

If doing a poo in a toilet at work or another public setting causes you anxiety, be kind to yourself. A number of strategies might help:

• identify and challenge negative thoughts about using public toilets and remind yourself that using the bathroom is normal, and that most people are not paying attention to others in the toilets
• try to manage stress through relaxation techniques such as deep breathing and progressive muscle relaxation, which involves tensing and relaxing different muscles around the body
• engaging in gradual exposure can be helpful, which means visiting public toilets at different times and locations, so you can develop greater confidence in using them
• use grounding or distraction techniques while going to the toilet. These might include listening to music, watching something on your phone, or focusing on your breathing.

If you feel parcopresis is having a significant impact on your life, talk to your GP or a psychologist who can help identify appropriate approaches to treatment. This might include cognitive behavioural therapy.

Simon Robert Knowles, Associate Professor and Clinical Psychologist, Swinburne University of Technology

This article is republished from The Conversation under a Creative Commons license. Read the original article.