8.3 Disorders of the CNS System
Now that we have reviewed basic concepts of neurotransmitters and their function, let’s review common central nervous system (CNS) disorders.[1]
Read additional information about mental health disorders in Open RN Nursing: Mental Health & Community Concepts.
Anxiety
Anxiety disorders are a group of conditions marked by pathological or extreme anxiety or dread. People with anxiety experience disturbances of mood, behavior, and body systems, making it difficult to complete everyday activities. Many feel anxious most of the time for no apparent reason.
Anxiety is different from fear. Fear is a person’s response to an event or object. The psychiatric disorder of anxiety occurs when the intensity and duration of anxiety does not match the potential for harm or threat to the affected person. Anxiety can be expressed behaviorally or experienced with physical symptoms.[2]
Signs and Symptoms of Anxiety
- Aches
- Pains
- Stomachaches
- Headaches
- Heart racing or pounding
- Trembling
- Sweating
- Difficulty concentrating (see Figure 8.5)[3]
- Increased agitation
- Crying
Treatment can include nonpharmacological interventions, as well as medications. Nonpharmacological interventions to decrease anxiety include relaxation techniques such as deep breathing, exercise, psychotherapy, support groups, or cognitive behavioral therapy. Antianxiety medications can also be used to help both verbal and nonverbal clients feel a much-needed sense of peace.
Read more about anxiety on the National Institute of Mental Health’s website.
Major Depressive Disorder
Major depressive disorder affects up to 5% of the U.S. population. To be diagnosed with major depressive disorder, five of the following symptoms must be present during the same two-week period and represent a change from previous functioning. The symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning. The symptoms of depression cannot be due to effects of a substance or from bereavement.
Signs and Symptoms of Depression
- Depressed mood
- Diminished interest
- Weight loss when not dieting or weight gain
- Insomnia or hypersomnia
- Agitation
- Fatigue or loss of energy
- Feeling of worthlessness
- Inappropriate guilt
- Diminished ability to concentrate
- Recurrent thoughts of death, suicidal ideation, or suicide attempt
Treatment of depression may include medication, psychotherapy, cognitive therapy, electroconvulsive therapy (ECT), and group therapy. Clients who are depressed may not report symptoms unless specifically asked, and they may be suicidal. Using assessment techniques to gather information about the history of each client’s depression, support system, specific triggering events, psychosocial assessment, and risk for harm to self or others is imperative. Each client’s response to medication is unpredictable, and often medications will need to be adjusted based on reported symptoms.
Read more about depression on the National Institute of Mental Health’s website.
Bipolar Disorder
Bipolar disorder is marked by serious mood swings. Typically, clients experience extreme highs (called mania or hypomania) alternating with extreme lows (depression). See the “Major Depressive Disorder” subsection for signs and symptoms of depression. Bipolar disorder and major depression disorder are also referred to as “affective mood disorders.” For some people, the cycles occur so rapidly that they hardly ever feel a sense of control over their mood swings.
Signs and Symptoms of a Manic Episode
- Rapid speech
- Hyperactivity
- Reduced need for sleep
- Flight of ideas
- Grandiosity
- Poor judgement
- Aggression/hostility
- Risky sexual behavior
- Neglect basic self-care
- Decreased impulse control
Treatment for a client diagnosed with bipolar may include medication, safety initiatives during acute mania, ECT, psychotherapy, and support groups. The severity of manic and depressive episodes varies for each client. Assessing if a client is a danger to others or themselves is the priority. People with bipolar may need assistance with impulse control during times when they are in a manic state.
Read more about bipolar disorder on the National Institute of Mental Health’s website.
Schizophrenia
Schizophrenia affects people from all walks of life and typically first appears between the ages of 15 and 30. Schizophrenia refers to a group of severe, disabling psychiatric disorders marked by withdrawal from reality, illogical thinking, delusions (fixed false beliefs that cannot be changed through reasoning), hallucinations (hearing, seeing, smelling, tasting, or feeling touched by things that are not there), and flat affect (lack of observable expressions of emotions, monotone voice, expressionless face, immobile body).
Signs and Symptoms of Schizophrenia
There are three categories of symptoms related to schizophrenia: positive, negative, and cognitive.
Positive Symptoms
Note that in this context, the term “positive” does not refer to “good.” Positive symptoms refer to how the individual has lost touch with reality. Positive symptoms include the following:
- Delusions
- Hallucinations
- Disorganized thinking and behavior
Delusions fall into several categories. Individuals with a persecutory delusion may believe they are being tormented, followed, tricked, or spied on. Individuals with a grandiose delusion may believe they have special powers. Individuals with a reference delusion may believe that passages in books, newspapers, television shows, song lyrics, or other environmental cues are directed toward them. In delusions of thought withdrawal or thought insertion, individuals believe others are reading their mind, their thoughts are being transmitted to others, or outside forces are imposing their thoughts or impulses on them.
Negative Symptoms
Negative symptoms refer to a lack of characteristics that should be present. Negative symptoms are as follows:
- Apathy (lack of interest in people, things, activities)
- Lack of motivation
- Blunted affect (lack of display of emotion)
- Poverty of speech (brief replies)
- Anhedonia (lack of interest in activities once enjoyed)
- Avoidance of relationships
Keep in mind that the inability to show emotion does not reflect an inability to feel emotion. Similarly, it is helpful to understand that withdrawing from others is a coping mechanism for an individual with schizophrenia and not a rejection of those who initiate contact.[4]
Cognitive
Cognitive symptoms refer to altered thought patterns and include these behaviors:
- Poor decision-making
- Loss of memory
- Distraction
- Difficulty focusing
Treatment
Treatment for a client diagnosed with schizophrenia may include medications to control positive and/or negative signs and symptoms and nonpharmacological interventions such as limit setting, therapeutic communication, ECT, and psychotherapy. Key assessments for a client with schizophrenia focus on safety with examination for hallucinations and delusions, identifying a support system, and reviewing medication with a focus on adherence to their prescribed therapeutic regimen.
Read more about schizophrenia on the National Institute of Mental Health’s website.
Attention-Deficit/Hyperactivity Disorder
Attention-deficit/hyperactivity disorder (ADHD) is characterized by hyperactivity, lack of impulse control, and/or lack of attention that interferes with how a person functions. ADHD is often diagnosed during childhood, but signs and symptoms can last through adulthood.
Signs and Symptoms of ADHD
- Hyperactivity
- Inability to concentrate
- Difficulty with self-control
- Lack of emotional control
A child with ADHD may have difficulty sitting still and focusing at school or have emotional outbursts. See Figure 8.6 for an illustration of the inability to focus on details.[5]
Medication, psychotherapy, behavior management, and family support all play a large part in helping an individual with ADHD. Providing resources for parents is also helpful.
Read more about ADHD on the National Institute of Mental Health’s website.
Seizures
The official definition of a seizure is “a transient occurrence of signs and/or symptoms due to an abnormal excessive or synchronous neuronal activity in the brain.” This means that during a seizure, large numbers of brain cells are activated abnormally at the same time. It is like an electrical storm in the brain. They may alter consciousness and produce abnormal motor activity. There are different classifications of seizures based on severity of symptoms.[7]
Signs and Symptoms of Seizures
Motor Symptoms
- Jerking (clonic)
- Muscles becoming limp or weak (atonic)
- Tense or rigid muscles (tonic)
- Brief muscle twitching (myoclonus)
- Epileptic spasms
Non-motor Symptoms
- Changes in sensation, emotions, thinking, or autonomic functions
- Lack of movement
Classification of Seizures
Seizures are classified in many ways, beginning with whether they are partial or generalized seizures.
Partial Seizures
Partial seizures have focal onset on one side of the brain. They are further classified into simple, complex, or secondarily generalized:
- Simple partial seizures are most common. They may also affect sensory and autonomic systems.
- Complex partial seizures include impairment of consciousness, with or without motor activity or other signs.
- Simple or complex partial seizures may become secondarily generalized, producing a tonic-clonic seizure.
Generalized Seizures
Generalized seizures have bilateral onset on both sides of the brain and are typified by petit mal seizures, which can be recognized by clinical characteristics, as well as interictal EEG abnormalities.[8]
Status Epilepticus
Status epilepticus is a state of repeated or continuous seizures. It is often defined operationally as a single seizure lasting more than 20 minutes or repeated seizures without recovery of consciousness. Prolonged status epilepticus leads to irreversible brain injury and has a very high rate of mortality. The goal of therapy should be to achieve control of a seizure within 60 minutes or less. Pharmacological treatment of seizures is very successful in the majority of cases, but it requires accurate diagnosis and classification of seizures. Medication management of seizures may include CNS depressants, benzodiazepines or barbiturates, or anticonvulsants such as phenytoin.
Parkinson’s Disease
Parkinson’s disease is a progressive disease of the nervous system that impairs one’s ability to move. The typical onset for Parkinson’s disease is middle to later stages of life. This disease worsens over time and has no cure. The cause of this disease is unknown, but it is known that it is characterized by a loss of dopaminergic neurons.
Signs and Symptoms of Parkinson’s Disease
- Tremor at rest
- Bradykinesia
- Muscle rigidity
- Postural instability
- Gait disturbance
- Dystonia
- Ophthalmoplegia
- Active mood disorders
See Figure 8.7 for a typical posture associated with clients with Parkinson’s disease.[9] Treatment for a client with Parkinson’s disease often includes medication to increase dopamine in the brain to slow the progression of the disease.
Potential New Treatment of Proteins in Alzheimer’s and Parkinson’s Disease
The underlying cause of some neurodegenerative diseases, such as Alzheimer’s and Parkinson’s, appears to be related to proteins—specifically, to proteins behaving badly. One of the strongest theories of what causes Alzheimer’s disease is based on the accumulation of beta-amyloid plaques, dense conglomerations of a protein that is not functioning correctly. Parkinson’s disease is linked to an increase in a protein known as alpha-synuclein that is toxic to the cells of the substantia nigra nucleus in the midbrain.
For proteins to function correctly, they are dependent on their three-dimensional shape. The linear sequence of amino acids folds into a three-dimensional shape that is based on the interactions between and among those amino acids. When the folding is disturbed and proteins take on a different shape, they stop functioning correctly. But the disease is not necessarily the result of functional loss of these proteins; rather, these altered proteins start to accumulate and may become toxic. For example, in Alzheimer’s the hallmark of the disease is the accumulation of these amyloid plaques in the cerebral cortex. The term coined to describe this sort of disease is “proteopathy,” and it includes other diseases. Creutzfeld-Jacob disease, the human variant of the disease known as mad cow disease, also involves the accumulation of amyloid plaques, similar to Alzheimer’s. Diseases of other organ systems can fall into this group as well, such as cystic fibrosis or type 2 diabetes. Recognizing the relationship between these diseases has suggested new therapeutic possibilities. Interfering with the accumulation of the proteins, and possibly as early as their original production within the cell, may unlock new ways to alleviate these devastating diseases.[10]
- This work is a derivative of Nursing: Mental Health & Community Concepts by Open RN licensed under CC BY 4.0 ↵
- This work is a derivative of Supporting Individuals With Intellectual Disability & Mental Illness by Sheri Melrose licensed under CC BY 4.0 ↵
- “stress-2902537_960_720.jpg” by TheDigitalArtist is licensed under CC0 1.0 ↵
- This work is a derivative of Supporting Individuals With Intellectual Disability & Mental Illness by Sheri Melrose licensed under CC BY 4.0 ↵
- “RightBrainDominant.jpg” by Elisa Riva is licensed under CC0 ↵
- Introduction to Mental Disorders by Khan Academy is licensed under CC BY-NC-SA 3.0 ↵
- Epilepsy Foundation. (2016, December 22). 2017 Revised classification of seizures. https://www.epilepsy.com/article/2016/12/2017-revised-classification-seizures ↵
- Epilepsy Foundation. (2016, December 22). 2017 Revised classification of seizures. https://www.epilepsy.com/article/2016/12/2017-revised-classification-seizures ↵
- “Paralysis agitans (1907, after St. Leger).png” by William Richard Gowers is licensed under CC0 ↵
- This work is a derivative of Anatomy and Physiology by OpenStax licensed under CC BY 4.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction ↵
A state of repeated or continuous seizures.
Usually tremor at rest; When person sits, arm shakes; tremor stops when person attempts to grab something (pill rolling tremor).
Slowness in initiation and execution of voluntary movements.
Increase muscle tone and increase resistance to movement (Arms and Legs Stiff) – as severity increases cogwheel rigidity.
Abnormal fixation of posture (stoop when standing), problems with equilibrium, and righting reflex.
An abnormal way of walking, such as shuffling feet.
Inappropriate and continuous muscle contraction.
Weakness in eye muscles.