Psychology

Schizophrenia
The Columbia Encyclopedia describes schizophrenia as a group of severe life long mental disorders characterized by distortion in reality perception and expression (2009). Schizophrenia may be manifested by hallucinations, paranoia, delusions, thought disorders, and disorganized behavior. There is no clear relationship between the emotions of a patient and the thoughts, and it has hence been referred to as split personality (The Colombia Encyclopedia, 2009). Schizophrenia can occur in various types such as paranoid, catatonic, and disorganized among others (Mayo clinic, 2010)

The causes of the condition are unknown but according to Mayo clinic (2010), an interaction of genetic and environmental aspects may lead to development of the condition. Mayo clinic adds that problems with glutamate and dopamine neurotransmitters may also contribute to the disease.
The cognitive problems involved in schizophrenia are as a result of complications with thought processes. The cognitive component of the condition is the most disabling as it affects the ability of the person to perform the basic daily tasks. According to Mayo clinic, the disabling cognitive symptoms include memory problems, inability to pay and maintain attention, and problems processing information.
The schizophrenic behavior ranges from unpredictable, strange to violent and suicidal (Mayo clinic, 2010). As the clinic notes, the odd behavior may be as a result of delusional beliefs.

Affectively, the condition can lead to depression and mood swing. Their odd behavior causes other people to avoid schizophrenic persons which lead to emotional and social isolation.

Psychosis
Psychosis is a broad psychiatric term that refers to a mental state characterized by loss of contact with reality, accompanied by delusions and hallucinations (Ellwood, 1995). Like schizophrenia, psychosis is a condition of the mind. However, unlike schizophrenia, the causes of psychosis are always clear. Ellwood notes that it is different from neurosis in that psychosis refers to a more serious state of mind whereby an individual is unable to function properly (1995).

Stahl (2000) notes that psychosis is a syndrome made up of a combination of symptoms that can be associated with many different psychiatric disorders. Stahl adds that the diagnostic schemes do not recognize psychosis as a specific disorder in itself. Some of the causes of psychosis include alcohol and drugs, dementia, brain tumors, brain diseases and chromosomal disorders, sleep deprivation, HIV, epilepsy, stroke, and other infections that affect the brain (Stahl, 2000).

Ellwood notes that like schizophrenia, psychosis is characterized by incoherent speech, unpredictable and often dangerous behavior, and disorganized thoughts (1995). She further notes that psychotic individuals are always detached as a result of their inability to express their emotions. In addition, they are usually depressed with mood swings.

Stahl notes that although the condition may not be permanent, the hallucinations and delusions make the person unable to process information and retain attention and this affects their ability to perform basic activities. Their behavior is more violent and unpredictable. Due to the many causes of psychosis, treatment is based on the cause. However, Stahl notes that cognitive behavior and family therapy may be effective.

Lifespan Development
Lifespan development involves the systematic changes and continuities that occur during life of a person. According to Sigelman and Rider (2008), the changes and continuities could be gains, losses or neutral in the physical, psychological, and cognitive functioning. The process begins at conception and ends at death. According to Sugarman (2001), lifespan development is methodical, intra-individual changes that are associated with advancing of age.

In order to understand lifespan development, the life of a person is separate into four stages infancy, childhood, adolescence, and adulthood (Sigelman and Rider, 2008) or developmental stages childhood and adolescence, early adulthood, mid-adulthood, and late adulthood (Sugarman, 2001). Each of this stage involves changes in the biology, emotional, cognitive, and behavioral aspects.

Sigelman and Rider (2008) point out that the development is a life-long and multi-directional. They note that it involves both the gains and losses. In each of the four stages of life, Sigelman and Rider note that people gain some aspects and lose others and it is not always true that what is gained during childhood is lost during the later years. They add that, the development is accompanied by life-long plasticity that enables people to respond to environmental influences.

Santrock (2008) points out that the Piagets theory of cognitive development explains how people acquire the intelligence to adapt to the environment. Stanrock points out that the theory has four stages and at each stage, intelligence is different. The stages identified are the Sensorimotor Stage, Pre-Operational Period, Concrete Operation Stage, and the Formal Operational Stage.