Pediatricians are often the first health professionals to assess and raise suspicions of RAD in children with the disorder. The initial presentation varies according to the child's developmental and chronological age, although it always involves a disturbance in social interaction. Infants up to about 18–24 months "may" present with non-organic failure to thrive and display abnormal responsiveness to stimuli. Laboratory investigations will be unremarkable barring possible findings consistent with malnutrition or dehydration, while serum growth hormone levels will be normal or elevated.

The core feature is severely inappropriate social relating by affected children. This can manifest itself in two ways:

1. Indiscriminate and excessive attempts to receive comfort and affection from any available adult, even relative strangers (older children and adolescents may also aim attempts at peers).

2. Extreme reluctance to initiate or accept comfort and affection, even from familiar adults, especially when distressed.

While RAD is likely to occur in relation to neglectful and abusive treatment, automatic diagnoses on this basis alone cannot be made, as children can form stable attachments and social relationships despite marked abuse and neglect.

The name of the disorder emphasizes problems with attachment but the criteria includes symptoms such as failure to thrive, a lack of developmentally appropriate social responsiveness, apathy, and onset before 8 months.

Reactive attachment disorder (RAD) is described in clinical literature as a severe and relatively uncommon disorder that can affect children. RAD is characterized by markedly disturbed and developmentally inappropriate ways of relating socially in most contexts. It can take the form of a persistent failure to initiate or respond to most social interactions in a developmentally appropriate way—known as the "inhibited form". Due to recent revision in the DSM-5 the "disinhibited form" is now considered a separate diagnosis named "Disinhibited attachment disorder".

RAD arises from a failure to form normal attachments to primary caregivers in early childhood. Such a failure could result from severe early experiences of neglect, abuse, abrupt separation from caregivers between the ages of six months and three years, frequent change of caregivers, or a lack of caregiver responsiveness to a child's communicative efforts. Not all, or even a majority of such experiences, result in the disorder. It is differentiated from pervasive developmental disorder or developmental delay and from possibly comorbid conditions such as intellectual disability, all of which can affect attachment behavior. The criteria for a diagnosis of a reactive attachment "disorder" are very different from the criteria used in assessment or categorization of attachment "styles" such as insecure or disorganized attachment.

Children with RAD are presumed to have grossly disturbed internal working models of relationships that may lead to interpersonal and behavioral difficulties in later life. There are few studies of long-term effects, and there is a lack of clarity about the presentation of the disorder beyond the age of five years. However, the opening of orphanages in Eastern Europe following the end of the Cold War in the early-1990s provided opportunities for research on infants and toddlers brought up in very deprived conditions. Such research broadened the understanding of the prevalence, causes, mechanism and assessment of disorders of attachment and led to efforts from the late-1990s onwards to develop treatment and prevention programs and better methods of assessment. Mainstream theorists in the field have proposed that a broader range of conditions arising from problems with attachment should be defined beyond current classifications.

Mainstream treatment and prevention programs that target RAD and other problematic early attachment behaviors are based on attachment theory and concentrate on increasing the responsiveness and sensitivity of the caregiver, or if that is not possible, placing the child with a different caregiver. Most such strategies are in the process of being evaluated. Mainstream practitioners and theorists have presented significant criticism of the diagnosis and treatment of alleged reactive attachment disorder or the theoretically baseless "attachment disorder" within the controversial form of psychotherapy commonly known as attachment therapy. Attachment therapy has a scientifically unsupported theoretical base and uses diagnostic criteria or symptom lists markedly different to criteria under ICD-10 or DSM-IV-TR, or to attachment behaviors. A range of treatment approaches are used in attachment "therapy", some of which are physically and psychologically coercive, and considered to be to attachment "theory". Many constitute abuse.

The fourth revision of the "Diagnostic and Statistical Manual" (DSM-IV-TR) (now replaced by DSM-5) stated that the child must exhibit four out of the eight signs and symptoms to meet the diagnostic threshold for oppositional defiant disorder. Furthermore, they must be perpetuated for longer than six months and must be considered beyond normal child behavior to fit the diagnosis. Signs and symptoms were: actively refuses to comply with majority's requests or consensus-supported rules; performs actions deliberately to annoy others; is angry and resentful of others; argues often; blames others for their own mistakes; frequently loses temper; is spiteful or seeks revenge; and is touchy or easily annoyed.

These patterns of behavior result in impairment at school and/or other social venues.

The ICD-10 includes a diagnostic guideline for the wide group of personality and behavioural disorders. However, every disorder has its own diagnostic criteria. In case of the organic personality disorder, patient has to show at least three of the following diagnostic criteria over a six or more months period. organic personality disorder is associated with a large variety of symptoms, such as deficits in cognitive function, dysfunctional behaviours, psychosis, neurosis, emotional changes, alterations in expression function and irritability. Patients with organic personality disorder can present emotional lability that means their emotional expressions are unstable and fluctuating. In addition, patients show reduction in ability of perseverance with their goals and they express disinhibited behaviours, which are characterised by inappropriate sexual and antisocial actions. For instance, patients can show dissocial behaviours, like stealing. Moreover, according to diagnostic guideline of ICD-10, patients can suffer from cognitive disturbances and they present signs of suspiciousness and paranoid ideas. Additionally, patients may present alteration in process of language production that means there are changes in language rate and flow. Furthermore, patients may show changes in their sexual preference and hyposexuality symptoms.

Another common feature of personality of patients with organic personality disorder is their dysfunctional and maladaptive behaviour that causes serious problems in these patients, because they face problems with pursuit and achievement of their goals. It is worth to be mentioned that patients with organic personality disorder express a feeling of unreasonable satisfaction and euphoria. Also, the patients show aggressive behaviours sometimes and these serious dysfunctions in their behaviour can have effects on their life and their relationships with other people. Specifically patients show intense signs of anger and aggression because of their inability to handle their impulses. The type of this aggression is called "impulsive aggression". Furthermore, it is worth to be mentioned that the pattern of organic personality disorder presents some similarities with pattern of temporal lobe epilepsy (TLE). Specifically patients who suffer from this chronic disorder type of epilepsy, express aggressive behaviours, likewise it happens to patients with organic personality disorder. Another similar symptom between Temporal lobe epilepsy and organic personality disorder is the epileptic seizure. The symptom of epileptic seizure has influence on patients' personality that means it causes behavioural alterations". The Temporal lobe epilepsy (TLE) is associated with the hyperexcitability of the medial temporal lobe (MTL) of patients. Finally, patients with organic personality disorder may present similar symptoms with patients, who suffer from the Huntington's disease as well. The symptoms of apathy and irritability are common between these two groups of patients.

People with HPD are usually high-functioning, both socially and professionally. They usually have good social skills, despite tending to use them to manipulate others into making them the center of attention. HPD may also affect a person's social and/or romantic relationships, as well as their ability to cope with losses or failures. They may seek treatment for clinical depression when romantic (or other close personal) relationships end.

Individuals with HPD often fail to see their own personal situation realistically, instead dramatizing and exaggerating their difficulties. They may go through frequent job changes, as they become easily bored and may prefer withdrawing from frustration (instead of facing it). Because they tend to crave novelty and excitement, they may place themselves in risky situations. All of these factors may lead to greater risk of developing clinical depression.

Additional characteristics may include:

- Exhibitionist behavior

- Constant seeking of reassurance or approval

- Excessive sensitivity to criticism or disapproval

- Pride of own personality and unwillingness to change, viewing any change as a threat

- Inappropriately seductive appearance or behavior of a sexual nature

- Using somatic symptoms (of physical illness) to garner attention

- A need to be the center of attention

- Low tolerance for frustration or delayed gratification

- Rapidly shifting emotional states that may appear superficial or exaggerated to others

- Tendency to believe that relationships are more intimate than they actually are

- Making rash decisions

- Blaming personal failures or disappointments on others

- Being easily influenced by others, especially those who treat them approvingly

- Being overly dramatic and emotional

Some people with histrionic traits or personality disorder change their seduction technique into a more maternal or paternal style as they age.

As it has already been mentioned, the organic personality disorder is included in a wide group of personality and behavioural disorders. This mental health disorder can be caused by disease, brain damages or dysfunctions in specific brain areas in frontal lobe. The most common reason for this profound change in personality is the traumatic brain injury (TBI). Children, whose brain areas have injured or damaged, may present Attention Deficit Hyperactivity Disorder (ADHD), oppositional defiant disorder (ODD) and organic personality disorder. Moreover, this disorder is characterised as "frontal lobe syndrome". This characteristic name shows that the organic personality disorder can usually be caused by lesions in three brain areas of frontal lobe. Specifically, the symptoms of organic personality disorder can also be caused by traumatic brain injuries in orbitofrontal cortex, anterior cingulate cortex and dorsolateral prefrontal cortex. It is worth to be mentioned that organic personality disorder may also be caused by lesions in other circumscribed brain areas.

A mnemonic that can be used to remember the characteristics of histrionic personality disorder is shortened as "PRAISE ME":

- Provocative (or seductive) behavior

- Relationships are considered more intimate than they actually are

- Attention-seeking

- Influenced easily by others or circumstances

- Speech (style) wants to impress; lacks detail

- Emotional lability; shallowness

- Make-up; physical appearance is used to draw attention to self

- Exaggerated emotions; theatrical

For a child or adolescent to qualify for a diagnosis of ODD, behaviours must cause considerable distress for the family or interfere significantly with academic or social functioning. Interference might take the form of preventing the child or adolescent from learning at school or making friends, or placing him or her in harmful situations. These behaviours must also persist for at least six months. Effects of ODD can be greatly amplified by other disorders in comorbidity such as ADHD. Other common comorbid disorders include depression and substance use disorders.

Attachment disorder is a broad term intended to describe disorders of mood, behavior, and social relationships arising from a failure to form normal attachments to primary care giving figures in early childhood. Such a failure would result from unusual early experiences of neglect, abuse, abrupt separation from caregivers between 6 months and three years of age, frequent change or excessive numbers of caregivers, or lack of caregiver responsiveness to child communicative efforts resulting in a lack of basic trust. A problematic history of social relationships occurring after about age three may be distressing to a child, but does not result in attachment disorder.

The term attachment disorder is used to describe emotional and behavioral problems of young children, and also applied to school-age children, teenagers and adults. The specific difficulties implied depend on the age of the individual being assessed, and a child's attachment-related behaviors may be very different with one familiar adult than with another, suggesting that the disorder is within the relationship and interactions of the two people rather than an aspect of one or the other personality. No list of symptoms can legitimately be presented but generally the term attachment disorder refers to the absence or distortion of age appropriate social behaviors with adults. For example, in a toddler, attachment-disordered behavior could include a failure to stay near familiar adults in a strange environment or to be comforted by contact with a familiar person, whereas in a six-year-old attachment-disordered behavior might involve excessive friendliness and inappropriate approaches to strangers.

There are currently two main areas of theory and practice relating to the definition and diagnosis of attachment disorder, and considerable discussion about a broader definition altogether. The first main area is based on scientific enquiry, is found in academic journals and books and pays close attention to attachment theory. It is described in ICD-10 as reactive attachment disorder, or "RAD" for the inhibited form, and disinhibited attachment disorder, or "DAD" for the disinhibited form. In DSM-IV-TR both comparable inhibited and disinhibited types are called reactive attachment disorder or "RAD".

The second area is controversial and considered pseudoscientific. It is found in clinical practice, on websites and in books and publications, but has little or no evidence base. It makes controversial claims relating to a basis in attachment theory. The use of these controversial diagnoses of attachment disorder is linked to the use of pseudoscientific attachment therapies to treat them.

Some authors have suggested that attachment, as an aspect of emotional development, is better assessed along a spectrum than considered to fall into two non-overlapping categories. This spectrum would have at one end the characteristics called secure attachment; midway along the range of disturbance would be insecure or other undesirable attachment styles; at the other extreme would be

non-attachment. Agreement has not yet been reached with respect to diagnostic criteria.

Finally, the term is also sometimes used to cover difficulties arising in relation to various attachment styles which may not be disorders in the clinical sense.

The diagnosis of PTSD was originally developed for adults who had suffered from a single event trauma, such as rape, or a traumatic experience during a war. However, the situation for many children is quite different. Children can suffer chronic trauma such as maltreatment, family violence, and a disruption in attachment to their primary caregiver. In many cases, it is the child's caregiver who caused the trauma. The diagnosis of PTSD does not take into account how the developmental stages of children may affect their symptoms and how trauma can affect a child’s development.

The term developmental trauma disorder (DTD) has also been suggested. This developmental form of trauma places children at risk for developing psychiatric and medical disorders. Bessel van der Kolk explains DTD as numerous encounters with interpersonal trauma such as physical assault, sexual assault, violence or death. It can also be characterized by subjective events like betrayal, defeat or shame.

Repeated traumatization during childhood leads to symptoms that differ from those described for PTSD. Cook and others describe symptoms and behavioural characteristics in seven domains:

- "Attachment" – "problems with relationship boundaries, lack of trust, social isolation, difficulty perceiving and responding to others' emotional states"

- "Biology" – "sensory-motor developmental dysfunction, sensory-integration difficulties, somatization, and increased medical problems"

- "Affect or emotional regulation" – "poor affect regulation, difficulty identifying and expressing emotions and internal states, and difficulties communicating needs, wants, and wishes"

- "Dissociation" – "amnesia, depersonalization, discrete states of consciousness with discrete memories, affect, and functioning, and impaired memory for state-based events"

- "Behavioural control" – "problems with impulse control, aggression, pathological self-soothing, and sleep problems"

- "Cognition" – "difficulty regulating attention, problems with a variety of 'executive functions' such as planning, judgement, initiation, use of materials, and self-monitoring, difficulty processing new information, difficulty focusing and completing tasks, poor object constancy, problems with 'cause-effect' thinking, and language developmental problems such as a gap between receptive and expressive communication abilities."

- "Self-concept" – "fragmented and disconnected autobiographical narrative, disturbed body image, low self-esteem, excessive shame, and negative internal working models of self".

Complex post-traumatic stress disorder (C-PTSD; also known as complex trauma disorder) is a psychological disorder thought to occur as a result of repetitive, prolonged trauma involving harm or abandonment by a caregiver or other interpersonal relationships with an uneven power dynamic. C-PTSD is associated with sexual, emotional or physical abuse or neglect in childhood, intimate partner violence, victims of kidnapping and hostage situations, indentured servants, victims of slavery, sweatshop workers, prisoners of war, victims of bullying, concentration camp survivors, and defectors of cults or cult-like organizations. Situations involving captivity/entrapment (a situation lacking a viable escape route for the victim or a perception of such) can lead to C-PTSD-like symptoms, which include prolonged feelings of terror, worthlessness, helplessness, and deformation of one's identity and sense of self.

Some researchers argue that C-PTSD is distinct from, but similar to PTSD, somatization disorder, dissociative identity disorder, and borderline personality disorder, with the main distinction being that it distorts a person's core identity, especially when prolonged trauma occurs during childhood development . It was first described in 1992 by Judith Herman in her book "Trauma & Recovery" and an accompanying article. Though peer-reviewed journals have published papers on C-PTSD, the category is not yet adopted by either the American Psychiatric Association's (APA) "Diagnostic and Statistical Manual of Mental Disorders", 5th Edition (DSM-5), or in the World Health Organization's (WHO) "International Statistical Classification of Diseases and Related Health Problems", 10th Edition (ICD-10). However, it is proposed for the ICD-11, to be finalized in 2018.

Emotional dysregulation in children can be associated with externalizing behaviors including

- exhibiting more extreme emotions

- difficulty identifying emotional cues

- difficulty recognizing their own emotions

- focusing on the negative

- difficulty controlling their attention

- being impulsive

- difficulty decreasing their negative emotions

- difficulty calming down when upset

Mental retardation is coded on Axis II of the DSM-IV-TR. The diagnostic criteria necessary in order to diagnose intellectual disability consists of:

There are varying degrees of intellectual disability, which are identified by an IQ test.

Mental retardation, Severity Unspecified: This unspecified diagnosis is given when there is a strong assumption that the child is mentally retarded, but cannot be tested because the individual is too impaired, not willing to take the IQ test or is an infant.

Emotional dysregulation in children can be associated with internalizing behaviors including

- exhibiting emotions too intense for a situation

- difficulty calming down when upset

- difficulty decreasing negative emotions

- being less able to calm themselves

- difficulty understanding emotional experiences

- becoming avoidant or aggressive when dealing with negative emotions

- experiencing more negative emotions

Disinhibited attachment disorder of childhood (DAD) according to the International Classification of Diseases (ICD-10), is defined as:

Disinhibited attachment disorder is a subtype of the ICD-10 category F94, "Disorders of social functioning with onset specific to childhood and adolescence". The other subtype of F94 is reactive attachment disorder of childhood (RAD – F94 .1).

Synonymous or similar disorders include Affectionless psychopathy and Institutional syndrome.

Within the ICD-10 category scheme, disinhibited attachment disorder specifically excludes Asperger syndrome (F84.5), hospitalism in children (F43.2), and hyperkinetic disorders (F90.-).

ICD-10 describes Reactive Attachment Disorder of Childhood, known as RAD, and Disinhibited Disorder of Childhood, less well known as DAD. DSM-IV-TR also describes Reactive Attachment Disorder of Infancy or Early Childhood. It divides this into two subtypes, Inhibited Type and Disinhibited Type, both known as RAD. The two classifications are similar and both include:

- markedly disturbed and developmentally inappropriate social relatedness in most contexts,

- the disturbance is not accounted for solely by developmental delay and does not meet the criteria for Pervasive Developmental Disorder,

- onset before 5 years of age,

- requires a history of significant neglect, and

- implicit lack of identifiable, preferred attachment figure.

ICD-10 includes in its diagnosis psychological and physical abuse and injury in addition to neglect. This is somewhat controversial, being a "commission" rather than "omission" and because abuse in and of itself does not lead to attachment disorder.

The inhibited form is described as "a failure to initiate or respond...to most social interactions, as manifest by excessively inhibited responses" and such infants do not seek and accept comfort at times of threat, alarm or distress, thus failing to maintain 'proximity', an essential element of attachment behavior. The disinhibited form shows "indiscriminate sociability...excessive familiarity with relative strangers" (DSM-IV-TR) and therefore a lack of 'specificity', the second basic element of attachment behavior. The ICD-10 descriptions are comparable. 'Disinhibited' and 'inhibited' are not opposites in terms of attachment disorder and can co-exist in the same child. The inhibited form has a greater tendency to ameliorate with an appropriate caregiver whilst the disinhibited form is more enduring.

While RAD is likely to occur following neglectful and abusive childcare, there should be no automatic diagnosis on this basis alone as children can form stable attachments and social relationships despite marked abuse and neglect. Abuse can occur alongside the required factors but on its own does not explain attachment disorder. Experiences of abuse are associated with the development of disorganised attachment, in which the child prefers a familiar caregiver, but responds to that person in an unpredictable and somewhat bizarre way. Within official classifications, attachment disorganization is a risk factor but not in itself an attachment disorder. Further although attachment disorders tend to occur in the context of some institutions, repeated changes of primary caregiver or extremely neglectful identifiable primary caregivers who show persistent disregard for the child's basic attachment needs, not all children raised in these conditions develop an attachment disorder.

According to Michael First of the DSM-5 working committee the focus of a relational disorder, in contrast to other DSM-IV disorders, "is on the relationship rather than on any one individual in the relationship".

Relational disorders involve two or more individuals and a disordered "juncture", whereas typical Axis I psychopathology describes a disorder at the individual level. An additional criterion for a relational disorder is that the disorder cannot be due solely to a problem in one member of the relationship, but requires pathological interaction from each of the individuals involved in the relationship.

For example, if a parent is withdrawn from one child but not another, the could be attributed to a relational disorder. In contrast, if a parent is withdrawn from both children, the dysfunction may be more appropriately attributable to a disorder at the individual level.

First states that "relational disorders share many elements in common with other disorders: there are distinctive features for classification; they can cause clinically significant impairment; there are recognizable clinical courses and patterns of comorbidity; they respond to specific treatments; and they can be prevented with early interventions. Specific tasks in a proposed research agenda: develop assessment modules; determine the clinical utility of relational disorders; determine the role of relational disorders in the etiology and maintenance of individual disorders; and consider aspects of relational disorders that might be modulated by individual disorders."

The proposed new diagnosis defines a relational disorder as "persistent and painful patterns of feelings, behaviors, and perceptions" among two or more people in an important personal relationship, such a husband and wife, or a parent and children.

According to psychiatrist Darrel Regier, MD, some psychiatrists and other therapists involved in couples and marital counseling have recommended that the new diagnosis be considered for possible incorporation into the Diagnostic and Statistical Manual of Mental Disorders (DSM IV).

Dissociative disorders (DD) are conditions that involve disruptions or breakdowns of memory, awareness, identity, or perception. People with dissociative disorders use dissociation, as a defence mechanism, pathologically and involuntarily. Dissociative disorders are sometimes triggered by psychological trauma, but may be preceded only by stress, psychoactive substances, or no identifiable trigger at all.

The dissociative disorders listed in the American Psychiatric Association's DSM-5 are as follows:

- Dissociative identity disorder (formerly multiple personality disorder): the alternation of two or more distinct personality states with impaired recall among personality states. In extreme cases, the host personality is unaware of the other, alternating personalities; however, the alternate personalities can be aware of all the existing personalities. This category now includes the old derealization disorder category.

- Dissociative amnesia (formerly psychogenic amnesia): the temporary loss of recall memory, specifically episodic memory, due to a traumatic or stressful event. It is considered the most common dissociative disorder amongst those documented. This disorder can occur abruptly or gradually and may last minutes to years depending on the severity of the trauma and the patient.

- Dissociative fugue (formerly psychogenic fugue) is now subsumed under the dissociative amnesia category. It is described as reversible amnesia for personal identity, usually involving unplanned travel or wandering, sometimes accompanied by the establishment of a new identity. This state is typically associated with stressful life circumstances and can be short or lengthy.

- Depersonalization disorder: periods of detachment from self or surrounding which may be experienced as "unreal" (lacking in control of or "outside" self) while retaining awareness that this is only a feeling and not a reality.

- The old category of dissociative disorder not otherwise specified is now split into two: Other specified dissociative disorder, and unspecified dissociative disorder. These categories are used for forms of pathological dissociation that do not fully meet the criteria of the other specified dissociative disorders, or if the correct category has not been determined.

Both dissociative amnesia and dissociative fugue usually emerge in adulthood and rarely occur after the age of 50. The ICD-10 classifies conversion disorder as a dissociative disorder while the DSM-IV classifies it as a somatoform disorder.

Separation anxiety disorder

- excessive stress when separated from home or family

- fear of being alone

- refusal to sleep alone

- clinginess

- excessive worry about safety

- excessive worry about getting lost

- frequent medical complaints with no cause

- refusal to go to school

Selective mutism

- unable to speak in certain social situations, even though they are comfortable speaking at home or with friends

- difficulty maintaining eye contact

- may have blank facial expressions

- stiff body movements

- may have a worrisome personality

- may be incredibly sensitive to sound

- difficulty with verbal and non-verbal expression

- may appear shy, when in reality, they have a fear of people.

Reactive attachment disorder of infancy or early childhood

- withdrawing from others

- aggressive attitude towards peers

- awkwardness or discomfort

- watching others but not engaging in social interaction

Stereotypic movement disorder

- head banging

- nail biting

- hitting or biting oneself

- hand waving or shaking

- rocking back and forth

Compulsive hoarding, also known as hoarding disorder, is a pattern of behavior that is characterized by excessive acquisition and an inability or unwillingness to discard large quantities of objects that cover the living areas of the home and cause significant distress or impairment. Compulsive hoarding behavior has been associated with health risks, impaired functioning, economic burden, and adverse effects on friends and family members. When clinically significant enough to impair functioning, hoarding can prevent typical uses of space, enough so that it can limit activities such as cooking, cleaning, moving through the house, and sleeping. It can also put the individual and others at risk of fires, falling, poor sanitation, and other health concerns. Compulsive hoarders may be aware of their irrational behavior, but the emotional attachment to the hoarded objects far exceeds the motive to discard the items.

Researchers have only recently begun to study hoarding, and it was first defined as a mental disorder in the 5th edition of the DSM in 2013. It was not clear whether compulsive hoarding is a separate, isolated disorder, or rather a symptom of another condition, such as OCD, but the current DSM lists hoarding disorder as both a mental disability and a possible symptom for OCD. Prevalence rates have been estimated at 2% to 5% in adults, though the condition typically manifests in childhood with symptoms worsening in advanced age, at which point collected items have grown excessive and family members who would otherwise help to maintain and control the levels of clutter have either died or moved away. Hoarding appears to be more common in people with psychological disorders such as depression, anxiety and attention deficit hyperactivity disorder (ADHD). Other factors often associated with hoarding include alcohol dependence, paranoid schizotypal and avoidance traits.

In 2008, a study was conducted to determine if there is a significant link between hoarding and interference in occupational and social functioning. Hoarding behavior is often severe because hoarders do not recognize it as a problem. It is much harder for behavioral therapy to successfully treat compulsive hoarders with poor insight about their disorder. Results show that hoarders were significantly less likely to see a problem in a hoarding situation than a friend or a relative might. This is independent of OCD symptoms, as people with OCD are often very aware of their disorder, which suggests a possible association with OCPD where the behavior are ego-syntonic. The opposite condition is compulsive decluttering.

In psychology, relationship obsessive–compulsive disorder (ROCD) is a form of obsessive-compulsive disorder focusing on intimate relationships (whether romantic or non-romantic). Such obsessions can become extremely distressing and debilitating, having negative impacts on relationships functioning.

Compulsive hoarding in its worst forms can cause fires, unsanitary conditions (such as rat and roach infestations), and other health and safety hazards.

Listed below are possible symptoms hoarders may experience:

- They hold onto a large number of items that most people would consider useless or worthless, such as:

- Junk mail, old catalogs, magazines, and newspapers

- Worn out cooking equipment

- Things that might be useful for making crafts

- Clothes that might be worn one day

- Broken things or trash

- "Freebies" or other promotional products

- Their home is cluttered to the point where many parts are inaccessible and can no longer be used for intended purposes. For example:

- Beds that cannot be slept in

- Kitchens that cannot be used for food preparation

- Tables, chairs, or sofas that cannot be used for dining or sitting

- Unsanitary bathrooms

- Tubs, showers, and sinks filled with items and can no longer be used for washing or bathing.

- Their clutter and mess is at a point where it can cause illness, distress, and impairment. As a result, they:

- Do not allow visitors in, such as family and friends, or repair and maintenance professionals, because the clutter embarrasses them

- Are reluctant or unable to return borrowed items

- Keep the shades drawn so that no one can look inside

- Get into a lot of arguments with family members regarding the clutter

- Are at risk of fire, falling, infestation, or eviction

- Often feel depressed or anxious due to the clutter

Children with underlying medical or mental health problems may exhibit some of the symptoms. Indeed, where the difficulties are not predicated in the parental-child nexus, many loving parents may be judged as "spoiling" instead of affirmed. Speech or hearing disorders, and attention deficit disorder, may lead to children's failing to understand the limits set by parents. Children who have recently experienced a stressful event, such as the separation of the parents (divorce) or the birth or death of a close family relative, may also exhibit some or all of the symptoms. Children of parents who themselves have psychiatric disorders may manifest some of the symptoms, because the parents behave erratically, sometimes failing to perceive their children's behavior correctly, and thus fail to properly or consistently define limits of normal behavior for them.

Dissociative disorders (DD) are widely believed to have roots in traumatic childhood experience (abuse or loss), but symptomology often goes unrecognized or is misdiagnosed in children and adolescents. There are several reasons why recognizing symptoms of dissociation in children is challenging: it may be difficult for children to describe their internal experiences; caregivers may miss signals or attempt to conceal their own abusive or neglectful behaviors; symptoms can be subtle or fleeting; disturbances of memory, mood, or concentration associated with dissociation may be misinterpreted as symptoms of other disorders.

In addition to developing diagnostic tests for children and adolescents (see above), a number of approaches have been developed to improve recognition and understanding of dissociation in children. Recent research has focused on clarifying the neurological basis of symptoms associated with dissociation by studying neurochemical, functional and structural brain abnormalities that can result from childhood trauma. Others in the field have argued that recognizing disorganized attachment (DA) in children can help alert clinicians to the possibility of dissociative disorders.

Clinicians and researchers also stress the importance of using a developmental model to understand both symptoms and the future course of DDs. In other words, symptoms of dissociation may manifest differently at different stages of child and adolescent development and individuals may be more or less susceptible to developing dissociative symptoms at different ages. Further research into the manifestation of dissociative symptoms and vulnerability throughout development is needed. Related to this developmental approach, more research is required to establish whether a young patient’s recovery will remain stable over time.

Obsessive-compulsive disorder comprises thoughts, images or urges that are unwanted, distressing, interfere with a person's life and that are commonly experienced as contradicting a persons' beliefs and values. Such intrusive thoughts are frequently followed by compulsive behaviors aimed at "neutralizing" the feared consequence of the intrusions and temporarily relieve the anxiety caused by the obsessions. Attempts to suppress or "neutralize" obsessions increase rather than decrease the frequency and distress caused by the obsessions.

Common obsessive themes include fear of contamination, fears about being responsible for harming the self or others, doubts, and orderliness. However, people with OCD can also have religious and sexual obsessions. Some people with OCD may experience obsessions relating to the way they feel in an ongoing relationship or the way they felt in past relationships (ROCD). Repetitive thought about a person's feelings in intimate relationships may occur in the natural course of the relationship development; however, in ROCD such preoccupations are unwanted, intrusive, chronic and disabling.