[5] The amount of speech may be normal but conveys little information because it is vague, empty, stereotyped, overconcrete, overabstract, or repetitive.
[6] Under Scale for the Assessment of Negative Symptoms used in clinical research, thought blocking is considered a part of alogia, and so is increased latency in response.
The alternative meaning of alogia is inability to speak because of dysfunction in the central nervous system,[10][3] found in mental deficiency and dementia.
Usually, an injury to the left side of the brain may cause alogia to appear in an individual.
[citation needed] Studies have shown a correlation between alogic ratings in individuals and the amount and duration of pauses in their speech when responding to a series of questions posed by the researcher.
[15] A study investigating alogiacs and their results on the category fluency task showed that people with schizophrenia who exhibit alogia display a more disorganized semantic memory than controls.
"[19] Alogia can be brought on by frontostriatal dysfunction which causes degradation of the semantic store, the center located in the temporal lobe that processes meaning in language.
Another study found that when given the task of naming items in a category, schizophrenia patients displayed a great struggle but improved significantly when experimenters employed a second stimulus to guide behavior unconsciously.
This conclusion was similar to results produced from patients with Huntington's and Parkinson's disease, ailments which also involve frontostriatal dysfunction.
[20] Medical studies conclude that certain adjunctive drugs effectively palliate the negative symptoms of schizophrenia, mainly alogia.
[21] D-amphetamine is another drug that has been tested on people with schizophrenia and found success in alleviating negative symptoms.
This treatment, however, has not been developed greatly as it seems to have adverse effects on other aspects of schizophrenia such as increasing the severity of positive symptoms.
Studies suggest that an inappropriate affect is strongly associated with bizarre behavior and positive formal thought disorder on a disorganization factor; attention impairment correlates significantly with psychotic, disorganization, and negative symptom factors.
[19] In schizophrenia, negative symptoms including flattening of affect, avolition, and alogia are responsible for the considerable morbidity of the disease compared with other psychotic disorders.
[27] Prominent negative symptoms at disease onset, including alogia, are good predictors of worse outcomes.