User:LBird BASc/sandbox/ATK/Seminar6/Truth/Neuroscience and Schizophrenia

Neuroepistemology

An empirical approach to epistemology. It is based on modern neuroscience and seeks to study the structure and functions of the brain with a focus on the direct relationship between the brain and capabilities (and incapabilities) that are epistemic by nature.

Assumptive framework

• Contextual effects on assumptions shaped by socio-politico-historical factors.
• Relationships of power in a given field and their influence on thought.
• The comparison between objective systems of validity and concepts that may be subjective and/or dependent on their given contexts.

Application

• "Tacit biases" in observations - "assumptions on the nature of mind"
• Theory was not the result of data itself. Preconceived ideas (eg about the Central Nervous System) have appeared to affect research and theoretical outcomes.

Neuroscience and Truth

Whether theories concerning relationships between neural structures and their given functions can be accepted as ‘true’ if they have been influenced by beliefs is debatable.

Positive and Normative Statements in Neuroscience - Objective and Subjective Truths

Positive and Normative statements concern themselves with what is objectively and subjectively true respectively. Positive statements are verifiable via testable, empirical means whilst normative statements involve the input of beliefs and value judgements. The level of ‘truth’ behind such normative statements is therefore debatable.

What is objectively ‘true’ in Neuroscience may be the structure and its correlation to a given task/function but claims those structures hold certain functions might only be subjective truths. Evidence behind those claims might even be subject to criticism in terms of the methodology used to obtain that evidence.

Neuroscience employs a variety of objective, scientific research methods that are not open to interpretation or bias. They are reliable in that the same results can be replicated and obtained by different researchers, regardless of their background, ethnicity, age or gender. The degree of reliability is a good proxy for the degree of objective truth in any given claim or theory where the same results must be agreed upon universally.

However, the interpretation of such results - ie that a certain structure gives rise to a given function, might be subjective. This is especially so in the discussion of mental illnesses where even the categorisation of the functions as mental illnesses are subjective due to this being a topic that is culturally relative in nature, making it so that categorisations might be true in some cultures but not others.

Research in Schizophrenia

Biological Explanations - Ventral Striatum

Schizophrenia can be explained in biological terms with reference to the ventral striatum - a structure believed to have a role in motivation. Avolition in schizophrenia is typically explained by low activity levels in this region. Neurological research by Juckel et al. (2006) showed a negative correlation overall negative symptoms and ventral striatum activity. An objective truth in this is the negative correlation between negative symptoms and ventral striatum activity. However, the assumption that low activity levels cause avolition is subjectively true. It is an assumption where it could be true that the direction of causality is actually reversed - that avolition results in reduced information passing through the ventral striatum, resulting in lower activity levels. Furthermore, other explanations suggesting the role(s) of genetics, neurochemicals, pregnancy complications and even social factors might even completely disregard the role of the ventral striatum in schizophrenia.

Classification of Schizophrenia

The classification of schizophrenia as a ‘mental illness’ is a truth that is and is culturally relative.

Whether an individual receives a diagnosis also depends on the basis of classification and the individual performing the assessment(s). Reliability (inter-rater and criterion) in the classification of schizophrenia is also generally poor. Cheniaux et al. (2009) illustrated different assessment systems (ICD and DSM) as well as different psychiatrists performing the assessments produce disparate results in the number of diagnoses made.