Mental, physical and social health are vital aspects of any individual’s life and are completely interconnected and interdependent to the point that we cannot consider health without mental health. The more we understand this correlation, the clearer it becomes that mental health is central to the well-being of individuals, societies and countries.
2.1 Types of Mental Health Issues and Disorders
The
World Health Organization (WHO) [
3] conceptualises mental health as a ‘state of well-being in which the individual realises his or her abilities, can manage with the usual stresses of life, can work constructively and fruitfully and can contribute to their community’. According to [
8], mental health is the ability of individuals and all of us to feel, think and operate in ways that improve our ability to enjoy life and deal with our challenges. It is an optimistic sense of emotional and spiritual well-being that appreciates the significance of culture, equity, social justice, interconnections and personal dignity. Mental disorders result from a complex interaction of genetic, biological, personality and environmental factors with the brain as the final common pathway for controlling behaviour, cognition, mood and anxiety. Most mental disorders can be broadly classified as psychoses or neuroses. Psychoses (e.g., schizophrenia and bipolar disorder) are severe mental illnesses distinguished by acute symptoms such as delusions, hallucinations and the inability to objectively evaluate reality. Neuroses are less severe and more treatable illnesses, such as depression, anxiety and paranoia, as well as obsessive-compulsive disorder and
post-traumatic stress disorder (PTSD) [
9].
Mental disorders or illnesses are characterised by altered thinking, mood or behaviour or are associated with significant distress and impaired functioning. The symptoms of mental disorders vary from mild to severe, depending on the type of mental disorder, the individual, the family and the socioeconomic environment. Mental disorders take many forms, including mood disorders, schizophrenia, anxiety disorders, personality disorders, eating disorders and addictions such as substance dependence and gambling. According to World Mental Health Day 2019 [
10], based on global data for all ages genders, the most common mental disorders include depression 5.45%, anxiety disorders 3.34%, schizophrenia 1.78%, other mental disorders 1.01%, bipolar disorder 0.99%, conduct disorder 0.56%, intellectual disability 0.51%, autism spectrum 0.5%, eating disorders 0.34% and attention deficit hyperactivity disorder 0.12%, as illustrated in
Figure 1.
Among the major diseases, this survey addresses mental disorders such as depressive disorders, panic disorders, bipolar disorders, schizophrenia, anxiety disorders and ASDs and some proposed solutions using AI systems.
Depressive Disorders
Depressive disorders are a primary care disease and are one of the most common categories of psychiatric disorders [
11]. The WHO [
12] declares depression is a common mental disorder and one of the leading reasons for disability worldwide. Globally, a calculated 264 million people are affected by depression. Depression is a common and severe medical disorder that negatively affects how one feels, thinks and acts [
13]. Because of wrong perceptions, nearly 60% of people with depression do not seek medical help. Many sense that the stigma of a mental health disorder is unsuitable in society and may hinder personal and professional life. Depression causes sadness, and a loss of interest in activities once enjoyed. The standard features of all depressive disorders are sadness, emptiness, or irritable mood, attended by somatic and cognitive changes that affect the individual’s capacity to function [
14].
Bipolar Disorder
The American Psychiatric Association’s
Diagnostic and Statistical Manual of Mental Disorders (DSM-5) [
15] describes bipolar disorders as a class of brain disorders that cause severe fluctuation in a person’s mood, energy and capacity to function. Bipolar disorder occurs in up to 2.5% of the population [
16]. People with bipolar disorder experience great excitement, over-activity, deception, euphoria (mania) and other times of feeling sad and hopeless (e.g., depression). Bipolar disorder is characterised by at smallest one manic/hypo-manic or crossbred episode (mania and depression) with or without a history of influential depression [
8].
During the period of mood disorder, three or more of the subsequent symptoms have prevailed and have been present to a considerable degree [
16]:
–
Inflated self-esteem or grandiosity.
–
Reduced need for sleep (e.g., feels rested after only 3 hours).
–
More conversational than usual or pressured to keep talking.
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Flight of ideas or subjective knowledge that thoughts are racing.
–
Distractibility (i.e., attention is too easily drawn to unimportant or irrelevant external stimuli).
–
Addition in goal-directed activity (socially, at work or school, or sexually) or psychomotor agitation.
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Exaggerated involvement in pleasurable activities with a high possibility for painful consequences (e.g., engaging in unrestrained buying sprees, sexual improprieties, or foolish business investments).
ASD
ASD is a neurodevelopmental condition denoted by deficits in social communication and the presence of restricted interests and repetitive behaviours [
17]; other features are atypical patterns of activities and conduct, such as difficulty with the change from one activity to another, a focus on details and unusual reactions to sensations [
18]. Autism is an illness that usually starts in infancy, at the latest, in the first 3 years of life. Parents often become concerned because their child is not using words to communicate, even though he or she recites passages from videotapes or says the alphabet. Autism is a heterogeneous condition; no two children or adults with autism have the same profile, but difficulties fall into core domains that are reliably measured and usually consistent across time, even though specific behaviours may change with development [
19,
20].
People with autism are usually subject to stigma, intolerance and human rights violations. Care for people with autism needs to be accompanied by actions at community and societal levels for greater accessibility, inclusivity and support.
Panic Disorder
Panic disorder is a typical mental disorder that affects up to 5% of people at some point in life. It is often disabling, especially when complicated by agoraphobia and is associated with substantial functional morbidity and reduced quality of life [
21]. According to [
22], panic disorder is an anxiety disorder characterised by unexpected and repeated episodes of severe fear accompanied by physical symptoms that may include chest pain, heart palpitations, shortness of breath, dizziness or abdominal distress. Typical features of panic disorders [
23] are shows in
Table 1:
Schizophrenia
Schizophrenia is a specific reaction to severe anxiety, having its origin in childhood and experienced similarly and reinforced in a later time of life, and it generally affects a motivational use of progressive impairment of the abstract attitude [
24]. Schizophrenia is a syndrome: a group of signs and symptoms of unknown aetiology, defined mainly by observed signs of psychosis. Schizophrenia shows paranoid delusions and auditory hallucinations late in adolescence or earlier adulthood in its most common form. These manifestations of the disease have changed little over the past century. Schizophrenia is conceptualised as a psychotic disorder, and this change requires psychotic pathology in the diagnosis [
25]. Delusions, hallucinations and disorganised speech are core ‘positive symptoms’ diagnosed with high reliability and might reasonably be considered necessary for a reliable diagnosis of schizophrenia. People with schizophrenia have two to three times more potential to die earlier than the general population [
26].
Schizophrenia is a psychiatric disease with a complex and multi-factorial aetiology resulting from the cumulative effect of several risk factors. Among them, genetic factors reflect the weight of hereditary factors in the genesis of schizophrenia, in which susceptibility to various spectrum diseases is inherited. According to WHO [
27], schizophrenia is a psychosis, a type of mental disorder characterised by distorted thinking, perception, feelings, language, sense of self and behaviour. Typical experiences include hallucination: hearing, seeing, or feeling things not there.
Other everyday experiences include:
–
Delusion: selected false beliefs or suspicions not shared by others in the person’s culture and firmly held even when there is proof of the opposite.
–
Abnormal behaviour: disorganised behaviour such as wandering, mumbling, or laughing to self, strange appearance, self-neglect, or unkempt.
–
Disorganised speech: incoherent or irrelevant speech;
–
Disturbances of emotions: marked apathy or disconnect between reported emotion and what is observed, such as a facial expression or body language.
2.2 Related Work
There is some research on specific types of AI-assisted diagnosis [
28,
30], monitoring [
28,
30,
31], predict [
32] and treatment [
28,
29,
33] applications for mental disorders. In [
28], the author explores applications in the prevention, supplementary diagnosis, treatment and rehabilitation of mental illness; the survey also discusses the advantages, shortcomings and opportunities of AI applications in mental disorders to provide references for research related to mental health applications based on AI technology. In [
32], the author explores AI and mental health that use
electronic health records (EHRs), brain imaging data, novel monitoring systems and social media platforms to predict, classify, or subgroup mental health diseases. In [
31], the author gives a survey on mental health monitoring systems using sensor data and ML.
This survey is different from existing ones because its scope is not limited to any specific type of application or algorithms but also to prevent, diagnose, monitor and treat mental illness, as summarised in
Table 2 that is not limited to one mental disease. The scope of application of this research includes the diagnosis, monitoring and prevention of various mental problems. The research provides a comprehensive summary and comparison of types of mental disorders and the role of IS in the automatic diagnosis and monitoring of mental disorders. ML classifiers usually fall into two primary categories: supervised learning and unsupervised learning. We also present several studies that used DL in their approaches. Finally, the research presents a brief discussion and future challenges of IS in aiding the diagnosis and monitoring of patients with mental problems.
2.2.1 Review Method.
A critical literature review was performed in this study to define a wide variety of methods of ML,
natural language processing (NLP), DL and multi-modal systems to help diagnose, monitor and treat patients with mental disorders and their markers in recent years until 2022 (2013–2022) as shown in
Figure 3. The
Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) [
35] method was used to discover and identify relevant articles. Selected articles were identified using the electronic literature search method of Google Scholar, WoS, Scopus, IEEE Xplore, PubMed and Science Direct using the query term combination of the search keywords. Keyword searches for suitable articles include: ‘Mental Health’, ‘Artificial Intelligence’, ‘Machine Learning’, ‘classification methods’, ‘classification problem’, ‘arrest methods’, ‘diagnostic methods’, ‘treatment methods’, ‘Large Language Models’, ‘mental health dataset’, ‘Transformers’ and ‘Natural Language Processing’ in the field of detection, diagnosis, treatment and monitoring of mental illnesses.
The search results were filtered to filter the articles that did not capture such discourse. The screening of articles was based on titles, abstracts and search keywords. The total number of reports collected at the end of the search was 271. After eliminating duplicate articles, the original number was reduced to 198. Based on the title and abstract review, we identified 153 records as eligible and excluded 45 records. The 153 selected articles were read and scanned to eliminate results that did not correlate with the research topic, resulting in 99 articles that we considered relevant to our study.
Ineligible articles were articles that performed text recognition from handwritten datasets, those whose datasets were not in English, articles written before 2013, articles unrelated to mental problems and articles that did not allow downloads. Criteria of Inclusion: articles in the English language, mobile applications, articles that used ML methods, DL methods, NLP methods and a combination of learning methods and articles that do not fulfil any inclusion criterion.
Finally, a total of 99 articles met our eligibility criteria. Most of the reviewed articles were published between 2015 and 2022. To summarise these articles, we grouped them into four categories according to the types of data analysed, including studies of the background of mental health, DL and ML algorithms, mobile applications and studies of mental health datasets.
Figure 2 presents a flowchart of the article selection process from the initial search stage to the final number of articles selected.