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.

Despite decades of research, navigating menopause seems to have become harder – with conflicting information on the internet, in the media, and from health care providers and researchers.

Adding to the uncertainty, a recent series in the Lancet medical journal challenged some beliefs about the symptoms of menopause and which ones menopausal hormone therapy (also known as hormone replacement therapy) can realistically alleviate.

So what symptoms reliably indicate the start of perimenopause or menopause? And which symptoms can menopause hormone therapy help with? Here’s what the evidence says.

Remind me, what exactly is menopause?

Menopause, simply put, is complete loss of female fertility.

Menopause is traditionally defined as the final menstrual period of a woman (or person female at birth) who previously menstruated. Menopause is diagnosed after 12 months of no further bleeding (unless you’ve had your ovaries removed, which is surgically induced menopause).

Perimenopause starts when menstrual cycles first vary in length by seven or more days, and ends when there has been no bleeding for 12 months.

Both perimenopause and menopause are hard to identify if a person has had a hysterectomy but their ovaries remain, or if natural menstruation is suppressed by a treatment (such as hormonal contraception) or a health condition (such as an eating disorder).

What are the most common symptoms of menopause?

Our study of the highest quality menopause-care guidelines found the internationally recognised symptoms of the perimenopause and menopause are:

• hot flushes and night sweats (known as vasomotor symptoms)
• disturbed sleep
• musculoskeletal pain
• decreased sexual function or desire
• vaginal dryness and irritation
• mood disturbance (low mood, mood changes or depressive symptoms) but not clinical depression.

However, none of these symptoms are menopause-specific, meaning they could have other causes.

In our study of Australian women, 38% of pre-menopausal women, 67% of perimenopausal women and 74% of post-menopausal women aged under 55 experienced hot flushes and/or night sweats.

But the severity of these symptoms varies greatly. Only 2.8% of pre-menopausal women reported moderate to severely bothersome hot flushes and night sweats symptoms, compared with 17.1% of perimenopausal women and 28.5% of post-menopausal women aged under 55.

So bothersome hot flushes and night sweats appear a reliable indicator of perimenopause and menopause – but they’re not the only symptoms. Nor are hot flushes and night sweats a western society phenomenon, as has been suggested. Women in Asian countries are similarly affected.

Depressive symptoms and anxiety are also often linked to menopause but they’re less menopause-specific than hot flushes and night sweats, as they’re common across the entire adult life span.

The most robust guidelines do not stipulate women must have hot flushes or night sweats to be considered as having perimenopausal or post-menopausal symptoms. They acknowledge that new mood disturbances may be a primary manifestation of menopausal hormonal changes.

The extent to which menopausal hormone changes impact memory, concentration and problem solving (frequently talked about as “brain fog”) is uncertain. Some studies suggest perimenopause may impair verbal memory and resolve as women transition through menopause. But strategic thinking and planning (executive brain function) have not been shown to change.

Who might benefit from hormone therapy?

The Lancet papers suggest menopause hormone therapy alleviates hot flushes and night sweats, but the likelihood of it improving sleep, mood or “brain fog” is limited to those bothered by vasomotor symptoms (hot flushes and night sweats).

In contrast, the highest quality clinical guidelines consistently identify both vasomotor symptoms and mood disturbances associated with menopause as reasons for menopause hormone therapy. In other words, you don’t need to have hot flushes or night sweats to be prescribed menopause hormone therapy.

Often, menopause hormone therapy is prescribed alongside a topical vaginal oestrogen to treat vaginal symptoms (dryness, irritation or urinary frequency).

However, none of these guidelines recommend menopause hormone therapy for cognitive symptoms often talked about as “brain fog”.

Despite musculoskeletal pain being the most common menopausal symptom in some populations, the effectiveness of menopause hormone therapy for this specific symptoms still needs to be studied.

Some guidelines, such as an Australian endorsed guideline, support menopause hormone therapy for the prevention of osteoporosis and fracture, but not for the prevention of any other disease.

What are the risks?

The greatest concerns about menopause hormone therapy have been about breast cancer and an increased risk of a deep vein clot which might cause a lung clot.

Oestrogen-only menopause hormone therapy is consistently considered to cause little or no change in breast cancer risk.

Oestrogen taken with a progestogen, which is required for women who have not had a hysterectomy, has been associated with a small increase in the risk of breast cancer, although any risk appears to vary according to the type of therapy used, the dose and duration of use.

Oestrogen taken orally has also been associated with an increased risk of a deep vein clot, although the risk varies according to the formulation used. This risk is avoided by using estrogen patches or gels prescribed at standard doses

What if I don’t want hormone therapy?

If you can’t or don’t want to take menopause hormone therapy, there are also effective non-hormonal prescription therapies available for troublesome hot flushes and night sweats.

In Australia, most of these options are “off-label”, although the new medication fezolinetant has just been approved in Australia for postmenopausal hot flushes and night sweats, and is expected to be available by mid-year. Fezolinetant, taken as a tablet, acts in the brain to stop the chemical neurokinin 3 triggering an inappropriate body heat response (flush and/or sweat).

Unfortunately, most over-the-counter treatments promoted for menopause are either ineffective or unproven. However, cognitive behaviour therapy and hypnosis may provide symptom relief.

The Australasian Menopause Society has useful menopause fact sheets and a find-a-doctor page. The Practitioner Toolkit for Managing Menopause is also freely available.

Susan Davis, Chair of Women’s Health, Monash University

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