PSYC344 Neurodivergence and Ageing (L8)

Neurodiversity =

The natural variation of all human minds/brains.

Includes people who are neurodivergent and neurotypical

Neurotypical =

A person who is NOT neurodivergent

Neurodivergent =

A person whose brain processes information differently to peers, leading to different experiences of and reactions to the world.

The neurodivergent umbrella includes many different neurotypes e.g. Autism, ADHD, Dyslexia etc.

1. Autism

A set of highly heritable lifelong heterogenous neurodevelopmental conditions.

(heterogenous = variability between people. Their experiences of the condition are very different)

(lifelong = innate, and not something people can grow out of)

DSMV-V characterisation = early developmental onset, across multiple contexts in both:

- social communication and interaction differences

- restrictive and repetitive patterns of behaviours, interests, activities

Features of Autism

- differences in adaptive functioning, perspective taking, sensory processing

- alexithymia (difficulties being able to recognise and express emotions)

- strong attention to detail

(Thrum et al., 2019)

Intellectual disability is also common - approx. 1 in 3 of those with autism

(Mason et al., 2022)

Many conditions also co-occur at high rates, but are not part of diagnostic criteria

- poor mental health

- higher support needs

- experience poor normative outcomes (barriers to education, employment, relationships and social integration)

Community Preferred Language

Identity first = 'Autistic person'

Person first = 'Person with Autism'

- avoid deficit framed language (e.g. disorder)

(Taboas et al., 2023)

Asked adults with autism their preferred language - over 85% prefer identity first

Adaptation of language is not about banning terms, but about considering the impact of language and aiming to be respectful

- preferred language is subjective and varies across cultures/context, and changes over time

Prevalence of Autism

UK case findings and meta-analysis suggest 1% (Brugha, 2016; Santomauro, 2024)

CDC suggests 3%, based on diagnosis rates in American children

More commonly diagnosed in men/boys than women/girls, estimated true ratio being 2:1 (Santomauro et al., 2024)

- however, this is not reflected in diagnosis rates due to biases in assessing autistic women and girls, who often go underdiagnosed

How is Autism Diagnosed

Traits often manifest early in life (though may fluctuate over the life course)

Diagnostic interviews are conducted by specialists multi-disciplinary team. Both individual and informant reports are taken into account.

- although traits emerge early in life, many do not receive a diagnosis until later life

Barriers to Diagnosis

The UK context is one of long waiting lists, and potentially differing practice in different diagnostic centres (some are diagnosing large majority of those who come in, others very few - suggests it is not standardised)

(Mandy et al.) = some UK centres had 35% diagnostic rate, others had 85% rates

Self-identification is increasingly being recognised as valid by neurodivergent communities, though opinions vary

Stereotyping Autism

(Botha et al., 2024)

Study looked at AI representations of autistic people using various prompts

- they all look miserable, alone, young men

- reflects societies stereotypes around autism

Autism in Midlife and Older Age

UK population (2023) = 68 million

- approx. 680,000 - 2,100,000 are autistic

The number of people living over 65 is set to increase by a third over the next 20 years. Although most autistic people are adults, age disparities are evident in health records

- 1 in 400 aged 40-49 have an autism diagnosis (0.24%)

- 1 in 1,400 aged 50+ have an autism diagnosis (<.01%)

People in mid-life and old age constitute a population who have many different health challenges and needs that are different to younger children

e.g.

- caring responsibilities

- health problems

These challenges intersect with being autistic

Lack of Older Adult Autism Research

(Mason et al., 2022)

Systematic review looking at all autism research.

- 34,000 focused on children

- 9,000 on adulthood

- only just over 170 (1%) focused on those with autism in old age (which in this study was those aged 50+)

The Underdiagnosis Problem

Most autistic people are adults, and most are undiagnosed.

Health records indicate that: (Stewart & Happe, 2025)

- 89% of autistic people in midlife are undiagnosed

- 96% of autistic people in old age are undiagnosed

Reasons for Underdiagnosis

There are several barriers to older autistic people receiving a diagnosis.

Autism was only introduced into the DSM in 1980, but since the diagnostic criteria has changed multiple times.

- prior emphasis on intellectual impairment

- poor understanding of heterogeneity

- difficulties with comorbidity

- early descriptions were of atypical male behaviour (why women are so frequently underdiagnosed)

- focused on childhood development

Lived Experience Perspectives of Diagnosis

(Mansour et al., 2025)

Interviews with autistic adults aged 65+

- shows that late diagnosis brings complex emotions e.g. feeling the need to re-evaluate their entire life through the lens of autism, often feeling confusion

- recurring theme of the difficultly growing up undiagnosed - feeling misunderstood, expected to 'be normal', or labelled as a 'nuisance'

Health Outcomes for Autistic People

(Hand et al., 2010)

Middle aged and older autistic adults have been found to have higher rates of most health conditions

- higher rates of common conditions such as mood disorders or gastrointestinal disorders

- aged-related conditions like Parkinson's disease, cognitive disorders, arthritis etc

(Vivanti et al., 2025)

Middle aged and older diagnosed autistic people have higher rates of dementia compared to non-autistic people

- Prevalence of early onset dementia in autistic people aged 30-64 was 4% (compared to 1% in general population)

- Prevalence over 65 was 30% (compared to 10% in general population)

(Stewart et al., 2020)

Growing evidence that autistic people have health issues throughout their lives

- higher rates of depression and anxiety

- higher rates of age-related conditions: mild cognitive impairments, arthritic conditions

More likely to have multiple mental health diagnoses

Limitation of studies:

- study focused on diagnosed sample, likely to vary from the autistic population in general

Mental Health Symptoms

(Eshetu et al., 2025)

Longitudinal analyses have indicated that people with high autistic traits are more likely to have persistent mental health symptoms

Tracked anxiety annually over a 7 ear period, those with high autistic traits were 12x more likely to be in the persistent high symptom class

Health Diagnoses

(O'Nions et al., 2024)

Looked at GP records for autistic and non-autistic adults and found that autistic adults, especially those with learning disabilities, are more likely to have many health problems that aren’t being diagnosed, suggesting big gaps in the care they receive.

How is Healthcare Experienced

Health care is particularly sought by older people, so it is important to understand how autism can effect these experiences.

(Masour et al., 2025)

Autistic people are impacted by the changing nature of services (need for clarity/sameness)

There are healthcare access challenges due to autistic differences and reduced social networks

Talking therapies -

Autistic people face barriers at ever stage of gaining access to NHS therapy/treatment

Experiences of Autistic Middle/Older Women

(Gillions et al., 2025)

May face particular challenges due to underdiagnosis and intersection with women's health

Themes identified in study:

1. stigma and stereotypes - lead to poor quality care

2. lifetime of negative experiences lead to lost confidence

3. there is a lot of effort required to navigate systems - puts them off getting help

4. anxiety about the future and hope for more autism friendly care

Life Experiences: Trauma

(Stewart et al., 2021)

Rates of all forms of trauma were reported more frequently by autistic people, including emotional neglect, physical abuse etc.

Transition Periods

Menopause:

Commonly occurs midlife, change in hormones.

As hormones fluctuate, symptoms can occur e.g.

- psychological (anxiety, fatigue, low mood)

- somatic/physical (headaches, muscle pain)

- vasomotor (hot flushes, night sweats)

(Charlton et al., 2025)

Autistic women experience more bothersome psychological and somatic (but not vasomotor) symptoms

Retirement:

When someone opts to leave employment, usually occurs at age 66 in the UK

There is only 1 multi-participant study on retirement in autistic populations (Kowalczyk et al., 2025)

- indicate poor retirement experiences, many retiring early/abruptly

- unplanned retirement in general population associated with poor experiences and hardship

Differences for Autistic retirement =

- fewer plans

- less stable employment prior to retirement

- lower eligibility for full UK state pension/employer pension

- less affordability of luxuries/optional expenses once retired

- greater concerns about being isolated without employment-related social contact

Although there were some between group similarities:

- comparable affordability of essential expenses

- similar hopes about retirement

Periods of Crisis

(Stewart et al., 2022)

Found to have higher rates of suicidality and suicidal behaviours compared to non-autistic comparison

(Roper et al., 2025)

Higher rates of suicidal ideation, deliberate self harm/deliberate suicidal self harm

- results remain when accounting for symptoms of depression

(Nuzum et al., 2025)

Direct effects between high autistic traits and suicidal ideation and suicidal self-harm were fully mediated by mental health and social problems

Highlights importance of mental health support for autistic (and high autistic trait) people

Life Expectancy Gap

(O'Nions et al., 2024)

From a cohort of nearly 10 million adults, autistic people (with and without intellectual disability) had substantially reduced life expectancy

- around 6-7 years shorter without intellectual disability

- up to 15 years shorter with intellectual disability

Likely due to higher health needs, limited support, and accumulated adverse experiences.

2. ADHD

Attention deficit/hyperactivity disorder

Defined as a neurodevelopmental condition characterised by:

- inattention

- hyperactivity and/or impulsivity

Characterised by persistent traits that occur in multiple contexts/settings and interferes with daily functioning

- highly heterogeneous and experiences vary substantially depending on a wide range of factors (e.g. age, gender, access to support)

Prevalence of ADHD

Estimated prevalence of adult ADHD based on world mental health surveys is 2.8%

However, a meta-analysis by (Popit et al., 2024) suggests that ADHD prevalence varies largely by study method

- ranging about 1-2% in register data (official healthcare records) to around 4-5% in survey and clinical study data

UK population based survey showed that most adults self-reporting ADHD characteristics are undiagnosed and not receiving support or intervention

ADHD Diagnosis

(John et al., in preparation)

Investigated ADHD diagnosis time trends by age and gender

- rising incidence of diagnoses over time

- much greater rise in female diagnoses, so much so that by 2024 male and female diagnoses equal

Historically men have been diagnosed far more than women, until 2020/21, where a rapid rise was seen.

- this could be due to increased recognition for ADHD in women

- also could be girls who couldn't get a diagnosis when they were younger now getting diagnosed (supported by data showing split between ages of diagnosis between men and women)

Older people still radically underdiagnosed

ADHD Health Outcomes

(John et al., in preparation)

- ADHD in children/young adults associated with poorer mental health (long term outcomes and underpinning reasons unclear)

Using data from the 1970 British Cohort

Findings:

1. childhood ADHD were linked to persistently higher psychological distress at all ages, more time-points with high levels of distress, greater likelihood of experiencing cumulative life course patterns

- this was partially mediated by social exclusion

2. higher childhood ADHD traits predicted poorer physical health by age 46, including more conditions, greater multimorbidity, more disability

- smoking, alcohol use, psychological distress, BMI and lower educational attainment were seen as potential pathways of this, with indirect associations

(El Baou et al., in preparation)

NHS talking therapy outcomes from over 3 million adults

Prevalence of co-occurring autism and ADHD was between 16-18%

- had worse outcomes

Life Expectancy Gap

(O'Nions et al., 2025)

Based on data from over 9.5 million people.

Adults diagnosed with ADHD lived, on average about 7-9 years less than similar adults without ADHD