Forgotten Features of the Schizophrenic Phenotype: Schizoidal Traits and Their Relation to Positive & Negative Schizotypy, Borderline Traits, Autistic Traits, and the Big Five

Forgotten Features of the Schizophrenic Phenotype: Schizoidal Traits and Their Relation to Positive & Negative Schizotypy, Borderline Traits, Autistic Traits, and the Big Five

Ahktar (1987) synthesized features of schizoid personality disorder, with consideration for personality aspects such as cognitive style, interests, experiences with love and sexuality, and ethics & worldview. Many of these traits however seem to have been forgotten about in modern research on schizotypy and schizophrenia spectrum disorders. In this study, I develop a set of items [Table 1] based on the traits outlined in Ahktar (1987), and investigate how they relate to positive and negative schizotypy.

Table 1

I’m usually fairly compliant.

I often refrain from expressing my emotional reactions if there is no logical point to doing so.

I’m not outwardly competitive

I rarely rely on others.

I am assertive (reverse)

I feel like I’m inferior and an outsider in life.

I feel slight sense of superiority to others

I feel disconnected from my sense of who I am as a person.

I find that I get uncomfortable with too much intimacy

I’m not much affected by other’s feelings

For most of my life I’ve not had many friends

I often come off as cold and distant to others

I’m very curious about the internal world of others.

I sometimes wish I could be spontaneous like others.

I deeply desire intimate connection but feel incapable of it

I am very sensitive but tend to hide this.

I prefer solitary activities

I’ve attached myself to political movements motivated by a need to belong

I am somewhat lazy.

I’m not sure what my real goals are in life.

My ethnicity and gender don’t influence my sense of who I am or with who I belong with

I’m capable of coming up with unique ideas and making original contributions

I avoid sexual intercourse but often engage in sexual fantasy.

I often wonder if people have romantic feelings towards me.

I have abnormal or taboo sexual interests.

I rarely develop genuine romantic interest in other people

I don’t particularly align with any political ideology or movement

My attitudes towards morality are not shared by many others

I am interested in the spiritual world.

I can be both altruistically self-sacrificing and immoral.

I have an elaborate fantasy life.

I can often be absent minded

The way I talk is often vague or overly-formal

At times I’m very articulate, but most of the time have difficulty expressing my thoughts.

I’m often preoccupied with my inner world and out of touch with the outside world

I engage in obsessive self reflection

Sometimes I feel as if I have sharp contact with external reality more so than others

With an online survey of 176 participants conducted using PsyToolkit (Stoet 2010, 2017), including these items and the Unusual Experiences & Introvertive Anhedonia subscales of the short O-LIFE (Mason et al. 2005) to measure positive and negative schizotypy. A scale was also created to measure borderline traits, and the extended version of the AQ-10 used in (Cloudfindings 2022) was used to measure autistic traits. 

The scree plot for the borderline trait measure suggested only the extraction of one factor, with most items loading highly on the factor [Table 2]. Factor scores were used in the analyses.

Table 2

Item	PC1
{reverse} I don't get jealous much.	-0.43
I sometimes feel the urge to engage in self destruction	-0.51
I often feel unable to control myself	-0.59
I tend to fixate on one specific person in my life and my thoughts tend to revolve around them.	-0.61
I am quick to make rash decisions.	-0.50
{reverse} I mostly trust others.	-0.35
When I'm under a lot of stress things start to feel unreal.	-0.54
I experience intense feelings of guilt.	-0.51
I don't usually think about the consequences before I act.	-0.49
I've made threats to hurt myself.	-0.53
I tend to treat things as good vs evil	-0.21
I'm not sure what my sexual orientation or gender identity is.	-0.47
When a relationship / close friendship ends I feel like I've lost everything.	-0.39
I often feel empty and bored.	-0.43
I feel like my name, assigned gender at birth, or other label does not represent me.	-0.37
{reverse} I have a pretty good sense of who I am and what my values are.	-0.49
I've purposely inflicted physical harm on myself or attempted suicide.	-0.46
I develop intense infatuations with people, almost to the point of obsession	-0.62
I cry more often than most people.	-0.30
I am quick to notice hints that someone I like is becoming disinterested in me.	-0.17
I have intense emotions and frequent mood swings.	-0.64
My feelings to those close to me constantly change.	-0.67
I constantly fear that my friends will leave me.	-0.50
I often have fits of anger.	-0.59

The autism questionnaire had a two factor structure, one relating to repetitive behaviors/details, the other to social difficulties, as in Cloudfindings (2021) [Table 3]. Oblimin rotated factor scores were used in the analyses.

Table 3

Item	F1	F2
I often notice small sounds when others do not	-0.51	-0.21
{reverse} I usually concentrate more on the whole picture, rather than the small details	-0.27	0.26
{reverse} I find it easy to do more than one thing at once	-0.01	0.51
{reverse} If there is an interruption, I can switch back to what I was doing very quickly	-0.18	0.35
{reverse} I find it easy to ‘read between the lines’ when someone is talking to me	-0.25	0.70
{reverse} I know how to tell if someone listening to me is getting bored	-0.35	0.58
When I’m reading a story I find it difficult to work out the characters’ intentions	-0.41	0.42
I like to collect information about categories of things (e.g. types of car, types of bird, types of train, types of plant etc)	-0.56	-0.18
{reverse} I find it easy to work out what someone is thinking or feeling just by looking at their face	-0.37	0.68
I find it difficult to work out people’s intentions	-0.37	0.62
I stick to the technical meaning of words rather than what other people think they mean.	-0.54	-0.22
Unless otherwise specified, I assume that people mean exactly what they say.	-0.54	0.10
I enjoy looking through catalogues of products to see the details of each product and how it compares to others.	-0.50	-0.37
When I learn about a new category I like to go into detail to understand the small differences between different members of that category.	-0.58	-0.33
If I look at a pile of blue sweaters in a shop that are meant to be identical, I would be able to see differences between them.	-0.65	-0.31
I would be the first to hear if there was a fly in the room	-0.53	-0.35
I rock backwards and forwards, or side to side, either when sitting or when standing	-0.59	0.08
I make repetitive hand and/or finger movements	-0.52	-0.04
I insist that aspects of daily routine must remain the same	-0.58	-0.11
I have a special object(s) I like to carry around	-0.52	-0.18

The schizoid items and schizotypy items were loaded into a principal components analysis, and the first two unrotated components were extracted to investigate the relationship between schizoid traits and positive & negative schizotypy. Unusual experiences and introverted anhedonia loaded positively on the first factor, and diametrically on the second factor. The first factor was interpreted as representing shared features of positive and negative schizotypy, and the second as opposing features of positive and negative schizotypy. The item loadings (not including O-LIFE items) on these factors are presented in table 4.

Table 4

Item	PC1 (pos + neg schizotypy)	PC2 (neg - vs positive)
I’m usually fairly compliant.	-0.26	0.29
I often refrain from expressing my emotional reactions if there is no logical point to doing so.	0.25	0.16
I’m not outwardly competitive	0.13	0.40
I rarely rely on others.	0.14	-0.28
I am assertive (reverse)	0.12	0.64
I feel like I’m inferior and an outsider in life.	0.48	0.42
I feel slight sense of superiority to others	0.33	-0.32
I feel disconnected from my sense of who I am as a person.	0.61	0.21
I find that I get uncomfortable with too much intimacy	0.59	0.15
I’m not much affected by other’s feelings	0.38	-0.06
For most of my life I’ve not had many friends	0.50	0.12
I often come off as cold and distant to others	0.59	0.01
I’m very curious about the internal world of others.	0.35	-0.07
I sometimes wish I could be spontaneous like others.	0.24	0.48
I deeply desire intimate connection but feel incapable of it	0.58	0.20
I am very sensitive but tend to hide this.	0.40	0.24
I prefer solitary activities	0.45	0.19
I’ve attached myself to political movements motivated by a need to belong	0.36	0.14
I am somewhat lazy.	0.30	0.40
I’m not sure what my real goals are in life.	0.37	0.48
My ethnicity and gender don’t influence my sense of who I am or with who I belong with	0.08	-0.03
I’m capable of coming up with unique ideas and making original contributions	0.15	-0.51
I avoid sexual intercourse but often engage in sexual fantasy.	0.44	0.12
I often wonder if people have romantic feelings towards me.	0.33	-0.17
I have abnormal or taboo sexual interests.	0.44	0.12
I rarely develop genuine romantic interest in other people	0.52	0.21
I don’t particularly align with any political ideology or movement	0.22	0.02
My attitudes towards morality are not shared by many others	0.46	-0.24
I am interested in the spiritual world.	0.27	-0.44
I can be both altruistically self-sacrificing and immoral.	0.54	-0.18
I have an elaborate fantasy life.	0.60	-0.19
I can often be absent minded	0.51	0.13
The way I talk is often vague or overly-formal	0.63	-0.02
At times I’m very articulate, but most of the time have difficulty expressing my thoughts.	0.59	0.19
I’m often preoccupied with my inner world and out of touch with the outside world	0.66	0.11
I engage in obsessive self reflection	0.60	-0.10
Sometimes I feel as if I have sharp contact with external reality more so than others	0.43	-0.45

Shared traits of positive and negative schizotypy included items reflecting depersonalisation, difficulty with social interactions and relationships despite desiring them, lack of friendships and social alienation, unusual sexual interests and fantasy, preoccupation with inner world, intense introspection, unconventional morals and beliefs, difficulty articulating thoughts and odd speech, and hidden social sensitivity. Creativity and spirituality were associated with higher positive schizotypy relative to negative schizotypy. Lack of assertiveness, lack of spontaneity, and lack of goals, were associated with higher negative schizotypy relative to positive schizotypy.  

The factor structure of the schizoidia items was investigated, the scree plot suggesting the extraction of three factors, which were oblimin rotated [Table 5]. These factors were titled schizoidal detachment, schizoidal openness, and schizoidal affect. Only schizoidal detachment and schizoidal affect correlated (r=0.25).

Table 5

	Schizoidal Detachment	Schizoidal Openness	Schizoidal Affect
I’m usually fairly compliant.	-0.14	-0.42	0.00
I often refrain from expressing my emotional reactions if there is no logical point to doing so.	-0.15	-0.19	0.64
I’m not outwardly competitive	0.14	-0.47	0.21
I rarely rely on others.	-0.27	0.32	0.45
{reverse} I am assertive	0.38	-0.63	-0.03
I feel like I’m inferior and an outsider in life.	0.66	-0.20	0.03
I feel slight sense of superiority to others	0.05	0.51	0.24
I feel disconnected from my sense of who I am as a person.	0.67	-0.03	0.12
I find that I get uncomfortable with too much intimacy	0.43	0.04	0.35
I’m not much affected by other’s feelings	-0.18	0.11	0.75
For most of my life I’ve not had many friends	0.17	0.02	0.52
I often come off as cold and distant to others	0.10	0.11	0.70
I’m very curious about the internal world of others.	0.44	0.16	-0.07
I sometimes wish I could be spontaneous like others.	0.45	-0.36	0.01
I deeply desire intimate connection but feel incapable of it	0.60	0.05	0.15
I am very sensitive but tend to hide this.	0.53	-0.10	0.03
I prefer solitary activities	0.15	-0.07	0.48
I’ve attached myself to political movements motivated by a need to belong	0.51	0.04	-0.10
I am somewhat lazy.	0.55	-0.28	-0.05
I’m not sure what my real goals are in life.	0.52	-0.36	0.12
My ethnicity and gender don’t influence my sense of who I am or with who I belong with	0.00	0.01	0.14
I’m capable of coming up with unique ideas and making original contributions	0.00	0.54	0.00
I avoid sexual intercourse but often engage in sexual fantasy.	0.37	0.03	0.20
I often wonder if people have romantic feelings towards me.	0.44	0.36	-0.17
I have abnormal or taboo sexual interests.	0.45	0.02	0.10
I rarely develop genuine romantic interest in other people	0.18	-0.12	0.63
I don’t particularly align with any political ideology or movement	0.00	-0.10	0.37
My attitudes towards morality are not shared by many others	0.09	0.28	0.44
I am interested in the spiritual world.	0.17	0.49	-0.07
I can be both altruistically self-sacrificing and immoral.	0.41	0.38	0.17
I have an elaborate fantasy life.	0.54	0.40	0.00
I can often be absent minded	0.66	0.09	-0.07
The way I talk is often vague or overly-formal	0.31	0.19	0.49
At times I’m very articulate, but most of the time have difficulty expressing my thoughts.	0.48	-0.07	0.35
I’m often preoccupied with my inner world and out of touch with the outside world	0.68	0.13	0.08
I engage in obsessive self reflection	0.57	0.31	0.07
Sometimes I feel as if I have sharp contact with external reality more so than others	0.05	0.58	0.28

I mistakenly did not include a measure of the big five personality traits in the survey, however to still attempt to investigate relations with the big five traits, three item scales were made from items from scales used in the study to attempt to measure the big five traits. Factor analysis was used to validate the scales, and items were replaced for six iterations until the items clearly loaded onto the respective big five factors that were attempting to be measured [Table 6].

Table 6

	Extraversion	Openness	Conscientiousness	Agreeableness	Neuroticism
I often come off as cold and distant to others	-0.76	0.18	-0.01	-0.06	0.00
For most of my life I’ve not had many friends	-0.75	0.00	-0.16	-0.01	-0.08
I prefer solitary activities	-0.72	-0.02	0.18	0.21	0.04
I’m capable of coming up with unique ideas and making original contributions	0.09	0.61	0.15	-0.04	0.19
Sometimes I feel as if I have sharp contact with external reality more so than others	-0.29	0.68	0.02	-0.07	-0.17
I am interested in the spiritual world.	0.06	0.79	-0.14	0.11	0.03
I am somewhat lazy.	-0.16	-0.12	-0.70	0.26	0.15
I don't usually think about the consequences before I act.	-0.08	0.11	-0.57	-0.23	0.20
I insist that aspects of daily routine must remain the same	-0.37	0.00	0.62	0.01	0.28
I’m not outwardly competitive	-0.14	-0.01	-0.24	0.75	0.08
{reverse} I mostly trust others.	-0.58	-0.14	-0.01	-0.44	0.11
I’m usually fairly compliant.	0.09	-0.02	0.20	0.69	-0.04
I have intense emotions and frequent mood swings.	-0.06	0.11	-0.30	-0.21	0.62
I experience intense feelings of guilt.	0.16	0.08	0.12	-0.02	0.79
I am very sensitive but tend to hide this.	-0.11	-0.07	-0.06	0.16	0.65

Relationships between the big five traits (measured through oblimin rotated factor scores) and the other traits measured in the study were investigated [Table 7]. Positive schizotypy was associated with openness, negative schizotypy with low extraversion, borderline traits with neuroticism, and autistic social deficits with low openness, in agreement with previous studies (Cloudfindings 2023). Using the method of Cloudfindings (2023) (without controlling for general psychopathology), factor analysis was used to map the traits onto the big five more clearly, the factors being oblimin rotated [Table 8]. Schizoidal affect corresponded to low extraversion, schizoidal openness to high openness, and schizoidal detachment to neuroticism. 

Table 7

	Extraversion	Openness	Conscientiousness	Agreeableness	Neuroticism
Schizoidal Detachment	-0.41	0.11	-0.33	0.05	0.62
Schizoidal Openness	-0.08	0.77	0.10	-0.56	0.08
Schizoidal Affect	-0.80	0.15	-0.01	0.03	0.09
Repetitive/Details	-0.50	0.32	0.20	-0.07	0.36
Social Deficit	-0.12	-0.26	-0.07	0.15	0.18
Borderline traits	-0.36	0.13	-0.35	-0.24	0.69
positive_schizotypy:1	-0.37	0.48	-0.06	-0.20	0.36
negative_schizotypy:1	-0.68	0.01	-0.02	0.02	0.20

Table 8

	Extraversion	Openness	Neuroticism	Conscientiousness	Agreeableness
Schizoidal Detachment	-0.24	0.05	0.68	-0.24	0.11
Schizoidal Openness	0.00	0.74	-0.01	0.09	-0.43
Schizoidal Affect	-0.90	0.12	-0.14	0.01	0.09
Repetitive/Details	-0.46	0.27	0.35	0.34	0.02
Social Deficit	-0.09	-0.38	0.38	0.03	0.12
Borderline traits	-0.14	0.02	0.74	-0.24	-0.22
Unusual Experiences	-0.30	0.48	0.36	0.00	-0.08
Introvertive anhedonia	-0.76	-0.09	0.10	0.05	0.05

Correlations between measured traits are displayed in Table 9.

Table 9

	Schizoidal Detachment	Schizoidal Openness	Schizoidal Affect	Repetitive/Details	Social Deficit	Borderline traits	Unusual Experiences
Schizoidal Openness	0.05
Schizoidal Affect	0.25	0.08
Repetitive/Details	0.39	0.29	0.44
Social Deficit	0.34	-0.30	0.00	0.14
Borderline traits	0.71	0.18	0.20	0.36	0.23
Unusual Experiences	0.46	0.47	0.35	0.54	0.02	0.57
Introvertive anhedonia	0.38	-0.04	0.59	0.44	0.25	0.31	0.33

1. Stoet (2010). PsyToolkit - A software package for programming psychological experiments using Linux.

2. Stoet (2017). PsyToolkit: A novel web-based method for running online questionnaires and reaction-time experiments

3. Mason et al. (2005) Short scales for measuring schizotypy.

4. Ahktar (1987) Schizoid personality disorder: a synthesis of developmental, dynamic, and descriptive features

5. Cloudfindings (2021) The Shared Etiology of Obsessive-Compulsive Behavior and Autistic Repetitive Behavior

6. Cloudfindings (2023) General Psychopathology Masks the Associations Between Psychiatric Disorders and Personality Traits