Inattentive ADHD or Sluggish Cognitive Tempo?

Sluggish Cognitive Tempo (SCT) is a term used to describe a cluster of symptoms related to attention and cognitive functioning. It is not officially recognised as a distinct disorder in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), but it has been the subject of research and clinical discussion.

It's important to note that SCT shares some overlapping symptoms with attention-deficit/hyperactivity disorder (ADHD), such as inattention and difficulty with task completion. However, SCT is considered by some researchers and clinicians to be a distinct condition with its own unique set of symptoms.

Those presenting with a predominantly inattentive type of ADHD, or those who feel like they have been inattentive but do not meet diagnostic criteria for ADHD, may have SCT.

6 features that characterise SCT

  1. Daydreaming and Mental Fog: People with SCT may frequently appear spacey, dreamy, or "mentally foggy." They often have difficulty staying focused on tasks and may seem like their mind is constantly wandering.
  2. Slowed Thinking and Processing: Cognitive processing in individuals with SCT is often slower than average. They may take longer to respond to questions or complete tasks, and they may struggle with tasks that require quick thinking. It is important to note that SCT is not related to intelligence, with it being possible to be above average intelligence and still present with SCT.
  3. Lethargy and Low Energy: People with SCT may experience chronic feelings of tiredness, fatigue, or low energy levels. This can lead to difficulties with motivation and productivity.
  4. Forgetfulness: Forgetfulness is common in individuals with SCT. They may have trouble remembering important details, appointments, or instructions.
  5. Procrastination: SCT is often associated with a tendency to procrastinate on tasks. Individuals with SCT may struggle to initiate and complete tasks, even if they are fully aware of the importance of doing so.
  6. Social Withdrawal: Some individuals with SCT may be socially withdrawn or have difficulty engaging in social interactions. They may appear shy or passive in social situations.

While SCT tends to be more passive, daydreamy, and lackadaisical, ADHD tends to be highly active, with a rapidly shifting focus accounting for a difficulty in sustaining attention, making careless mistakes, and being forgetful, which may also display features of impatience with excessive fidgeting, difficulty remaining seated, and blurting out answers.

Social withdrawal in SCT

Symptoms of SCT are often quite the opposite of those with predominantly hyperactive-impulsive or combined type ADHD. Instead of being hyperactive, outgoing, assertive, overly energetic, and risk-prone, individuals with SCT tend to be more passive, absent-minded, lethargic, introspective, and prone to daydreaming. They often describe themselves as feeling "in a fog" and appear somewhat disconnected from their surroundings.

SCT is commonly associated with internalising issues like anxiety, sadness, or depression. Across various studies, a consistent pattern of reserved and withdrawn behaviour in social interactions, particularly with peers, has been observed. Slower processing and response times can lead to hesitance in responding to social cues, which is frequently misinterpreted by others as aloofness or disinterest. This can create a feedback loop where the SCT individual hesitates and those around them pull back, leading to further hesitation, greater social distancing, and a felt sense of being overlooked and excluded.

One study observed this social withdrawal in SCT after controlling for ADHD subtype, IQ, reading and typing proficiency in an online chatroom environment. The study identified SCT as an independent predictor for reduced overall participation in the chat room, decreased perception of subtle social cues, diminished recall of conversation details, and a lower proportion of hostile responses.

In contrast, individuals with classic ADHD often face rejection due to their socially intrusive or aggressive behaviour. Those with ADHD are also more likely than those with SCT to exhibit antisocial behaviors such as substance abuse, oppositional-defiant disorder, or conduct disorder (involving behaviors like lying, stealing, and fighting).

Differences in attention between ADHD and SCT

Individuals displaying SCT symptoms often exhibit deficits in attention relating to a genuine challenge in information processing. This can manifest as difficulty focusing attention on specific details or discerning quickly between important and unimportant information. Conversely, people with ADHD struggle more with maintaining attention and consistently working towards goals while resisting distractions. Unlike SCT, those with classic ADHD may have problems with inhibiting their impulses but don't typically struggle with selecting and filtering sensory input.

Some experts suggest that SCT and ADHD result in different forms of inattention. Individuals with ADHD can engage their attention but struggle to sustain it over time, whereas those with SCT may have difficulty initially engaging their attention in a specific task. Consequently, research has indicated that the ability to direct attention may be impaired in individuals with SCT.


Research on SCT is ongoing and little is known about the causes, treatment, or prognosis. Some studies suggest that medication targeting ADHD is ineffective for SCT.

There is still debate within the mental health community about its classification and diagnostic criteria. As might be evident from this article, some experts believe SCT could be a separate condition to ADHD, however, others still argue that SCT may represent a subtype of ADHD. As further studies progress our understanding of SCT its classification are likley to evolve.

If you suspect you or someone you know may have symptoms related to SCT, please seek the guidance of a mental health professional.