Can you imagine hearing yourself speak? A voice inside your head – perhaps reciting a shopping list or a phone number? What would life be like if you couldn’t?

Some people, including me, cannot have imagined visual experiences. We cannot close our eyes and conjure an experience of seeing a loved one’s face, or imagine our lounge room layout – to consider if a new piece of furniture might fit in it. This is called “aphantasia”, from a Greek phrase where the “a” means without, and “phantasia” refers to an image. Colloquially, people like myself are often referred to as having a “blind mind”.

While most attention has been given to the inability to have imagined visual sensations, aphantasics can lack other imagined experiences. We might be unable to experience imagined tastes or smells. Some people cannot imagine hearing themselves speak.

A recent study has advanced our understanding of people who cannot imagine hearing their own internal monologue. Importantly, the authors have identified some tasks that such people are more likely to find challenging.

What the study found

Researchers at the University of Copenhagen in Denmark and at the University of Wisconsin-Madison in the United States recruited 93 volunteers. They included 46 adults who reported low levels of inner speech and 47 who reported high levels.

Both groups were given challenging tasks: judging if the names of objects they had seen would rhyme and recalling words. The group without an inner monologue performed worse. But differences disappeared when everyone could say words aloud.

Importantly, people who reported less inner speech were not worse at all tasks. They could recall similar numbers of words when the words had a different appearance to one another. This negates any suggestion that aphants (people with aphantasia) simply weren’t trying or were less capable.

A welcome validation

The study provides some welcome evidence for the lived experiences of some aphants, who are still often told their experiences are not different, but rather that they cannot describe their imagined experiences. Some people feel anxiety when they realise other people can have imagined experiences that they cannot. These feelings may be deepened when others assert they are merely confused or inarticulate.

In my own aphantasia research I have often quizzed crowds of people on their capacity to have imagined experiences.

Questions about the capacity to have imagined visual or audio sensations tend to be excitedly endorsed by a vast majority, but questions about imagined experiences of taste or smell seem to cause more confusion. Some people are adamant they can do this, including a colleague who says he can imagine what combinations of ingredients will taste like when cooked together. But other responses suggest subtypes of aphantasia may prove to be more common than we realise.

The authors of the recent study suggest the inability to imagine hearing yourself speak should be referred to as “anendophasia”, meaning without inner speech. Other authors had suggested anauralia (meaning without auditory imagery). Still other researchers have referred to all types of imagined sensation as being different types of “imagery”.

Having consistent names is important. It can help scientists “talk” to one another to compare findings. If different authors use different names, important evidence can be missed.

We have more than 5 senses

Debate continues about how many senses humans have, but some scientists reasonably argue for a number greater than 20.

In addition to the five senses of sight, smell, taste, touch and hearing, lesser known senses include thermoception (our sense of heat) and proprioception (awareness of the positions of our body parts). Thanks to proprioception, most of us can close our eyes and touch the tip of our index finger to our nose. Thanks to our vestibular sense, we typically have a good idea of which way is up and can maintain balance.

It may be tempting to give a new name to each inability to have a given type of imagined sensation. But this could lead to confusion. Another approach would be to adapt phrases that are already widely used. People who are unable to have imagined sensations commonly refer to ourselves as “aphants”. This could be adapted with a prefix, such as “audio aphant”. Time will tell which approach is adopted by most researchers.

Why we should keep investigating

Regardless of the names we use, the study of multiple types of inability to have an imagined sensation is important. These investigations could reveal the essential processes in human brains that bring about a conscious experience of an imagined sensation.

In time, this will not only lead to a better understanding of the diversity of humans, but may help uncover how human brains can create any conscious sensation. This question – how and where our conscious feelings are generated – remains one of the great mysteries of science.

Derek Arnold, Professor, School of Psychology, The University of Queensland

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

Oral retinoids are a type of medicine used to treat severe acne. They’re sold under the brand name Roaccutane, among others.

While oral retinoids are very effective, they can have harmful effects if taken during pregnancy. These medicines can cause miscarriages and major congenital abnormalities (harm to unborn babies) including in the brain, heart and face. At least 30% of children exposed to oral retinoids in pregnancy have severe congenital abnormalities.

Neurodevelopmental problems (in learning, reading, social skills, memory and attention) are also common.

Because of these risks, the Australasian College of Dermatologists advises oral retinoids should not be prescribed a month before or during pregnancy under any circumstances. Dermatologists are instructed to make sure a woman isn’t pregnant before starting this treatment, and discuss the risks with women of childbearing age.

But despite this, and warnings on the medicines’ packaging, pregnancies exposed to oral retinoids continue to be reported in Australia and around the world.

In a study published this month, we wanted to find out what proportion of Australian women of reproductive age were taking oral retinoids, and how many of these women were using contraception.

Our results suggest a high proportion of women are not using effective contraception while on these drugs, indicating Australia needs a strategy to reduce the risk oral retinoids pose to unborn babies.

Contraception options

Using birth control to avoid pregnancy during oral retinoid treatment is essential for women who are sexually active. Some contraception methods, however, are more reliable than others.

Long-acting-reversible contraceptives include intrauterine devices (IUDs) inserted into the womb (such as Mirena, Kyleena, or copper devices) and implants under the skin (such as Implanon). These “set and forget” methods are more than 99% effective.

The effectiveness of oral contraceptive pills among “perfect” users (following the directions, with no missed or late pills) is similarly more than 99%. But in typical users, this can fall as low as 91%.

Condoms, when used as the sole method of contraception, have higher failure rates. Their effectiveness can be as low as 82% in typical users.

Oral retinoid use over time

For our study, we analysed medicine dispensing data among women aged 15–44 from Australia’s Pharmaceutical Benefit Scheme (PBS) between 2013 and 2021.

We found the dispensing rate for oral retinoids doubled from one in every 71 women in 2013, to one in every 36 in 2021. The increase occurred across all ages but was most notable in young women.

Most women were not dispensed contraception at the same time they were using the oral retinoids. To be sure we weren’t missing any contraception that was supplied before the oral retinoids, we looked back in the data. For example, for an IUD that lasts five years, we looked back five years before the oral retinoid prescription.

Our analysis showed only one in four women provided oral retinoids were dispensed contraception simultaneously. This was even lower for 15- to 19-year-olds, where only about one in eight women who filled a prescription for oral retinoids were dispensed contraception.

A recent study found 43% of Australian year 10 and 69% of year 12 students are sexually active, so we can’t assume this younger age group largely had no need for contraception.

One limitation of our study is that it may underestimate contraception coverage, because not all contraceptive options are listed on the PBS. Those options not listed include male and female sterilisation, contraceptive rings, condoms, copper IUDs, and certain oral contraceptive pills.

But even if we presume some of the women in our study were using forms of contraception not listed on the PBS, we’re still left with a significant portion without evidence of contraception.

What are the solutions?

Other countries such as the United States and countries in Europe have pregnancy prevention programs for women taking oral retinoids. These programs include contraception requirements, risk acknowledgement forms and regular pregnancy tests. Despite these programs, unintended pregnancies among women using oral retinoids still occur in these countries.

But Australia has no official strategy for preventing pregnancies exposed to oral retinoids. Currently oral retinoids are prescribed by dermatologists, and most contraception is prescribed by GPs. Women therefore need to see two different doctors, which adds costs and burden.

Rather than a single fix, there are likely to be multiple solutions to this problem. Some dermatologists may not feel confident discussing sex or contraception with patients, so educating dermatologists about contraception is important. Education for women is equally important.

A clinical pathway is needed for reproductive-aged women to obtain both oral retinoids and effective contraception. Options may include GPs prescribing both medications, or dermatologists only prescribing oral retinoids when there’s a contraception plan already in place.

Some women may initially not be sexually active, but change their sexual behaviour while taking oral retinoids, so constant reminders and education are likely to be required.

Further, contraception access needs to be improved in Australia. Teenagers and young women in particular face barriers to accessing contraception, including costs, stigma and lack of knowledge.

Many doctors and women are doing the right thing. But every woman should have an effective contraception plan in place well before starting oral retinoids. Only if this happens can we reduce unintended pregnancies among women taking these medicines, and thereby reduce the risk of harm to unborn babies.

Dr Laura Gerhardy from NSW Health contributed to this article.

Antonia Shand, Research Fellow, Obstetrician, University of Sydney and Natasha Nassar, Professor of Paediatric and Perinatal Epidemiology and Chair in Translational Childhood Medicine, University of Sydney

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