The questions arise frequently as to what is the relationship between the positive symptoms (psychotic phenomena and inappropriate behavior) and the negative symptoms (primarily withdrawal). There are at least two major hypotheses that suggest a causal explanation for the co-occurrence of these two sets of symptoms. Hypothesis one proposes that the attenuation caused by the negative symptoms (including a reduction in neurocognitive resources such as attention, memory and executive function) undercuts the individual’s capacity for reality testing. The second hypothesis postulates that the negative beliefs and delusions are sufficiently aversive as to motivate a total withdrawal of the individual including a reduction of neurocognitive functions.
Based on clinical observations, at present, I have come up with two hypotheses that might explain a common causal factor. See Below:
Hypothesis 1: Utilizing our present database we can propose the following: the self-certainty factor of the Beck Cognitive Insight Scale, which measures the tenacity of a delusional belief, is caused by the limitation on available neurocognitive resources (manifested by low scores on the GUR). In a longitudinal design, there will be a positive correlation between the neurocognitive function at baseline (GUR BATTERY) and the score on the self-certainty factor of the BCIS at follow-up.
Hypothesis 2: The perception of a dangerous situation (as manifested by the persecutory delusions) causes the deactivation of the total personality including the neurocognitive resources (GUR BATTERY).The BCIS at baseline should correlate with the GUR battery at follow-up, thus indicating the causal relationship from delusion to withdrawal.
Testing of Hypotheses:
Hypothesis 1: Executive functioning at baseline is NOT associated with self-certainty at follow-up (r = -.05).
Hypothesis 2: Self-certainty at baseline IS associated with executive functioning at follow-up (r = -.24)
It is apparent that hypothesis number one is refuted by the analysis while hypothesis number two is supported. The problem is not that the reduced neurocognitive deficiencies undercut the reality testing, but rather the delusions and hallucinations are sufficiently aversive to the individual so that there is a generalized withdrawal in investment in the outside world.
This was an interesting experiment to test out. However, it was unnecessary because we had previously tested these hypotheses in a paper by Bredemeier, Grant & Beck (2017) entitled “Exploring the Temporal Relationship Between Cognitive Insight and Neurocognition in Schizophrenia: A Prospective Analysis”. The findings for this paper were as follows: both in a clinical trial and follow up period, cognitive insight predicted neurocognitive performance suggesting that decreases in cognitive insight exist before decreases in neurocognitive performance.
The comprehensive answer to the relationship between positive and negative symptoms is only partly established, but we should discuss at our Friday meaning. As always, I would appreciate your feedback regarding this material.
Bredemeier,K., Beck, A.T., Grant,P.M. (2017) Exploring the Temporal Relationship Between Cognitive Insight and Neurocognition in Schizophrenia: A Prospective AnalysisClinical Psychological Science. Vol 6, Issue 1, pp. 76 –89 https://doi.org/10.1177/2167702617734019