Neurosurgery to Enhance Brain Function: Ethical Dilemmas for the Neuroscientist and Society

Introduction

Therapeutic cognitive enhancement procedures are already an established part of neurosurgical practice. Some fall within the therapeutic repertoire and are uncontentious for that reason. The most widespread example is the use of cerebrospinal fluid (CSF) diversion procedures to treat cognitive decline in normal pressure hydrocephalus (NPH) (Finney, 2009). NPH is characterized by a clinical triad which includes cognitive decline and memory loss (Hakim and Adams, 1965). Although not yet in widespread clinical use, there has also been some positive albeit transient results in the use of brain stimulation in minimally conscious states (Thibaut et al., 2014), and studies attempting to obtain long term improvements are being initiated. Both CSF diversion and brain stimulation are now being investigated for efficacy in Alzheimer’s disease and they understandably are in demand not only from the individual patients and their families, but also at the institutional level (Laxton et al., 2013). For example, The UN Covenant on Economic, Social and Cultural Rights has proposed that there is a fundamental individual right to attain the best possible mental and physical health. As new surgical interventions become available there is a perception that there is a right to access these if they are proven to be effective and despite ethical worries that neurological enhancement may carry dangers in terms of social function and competition with resourcing of adequate services for the support of neurologically impaired patients.

It is likely that cognitive-enhancing neurosurgical procedures currently under investigation, such as brain stimulation for dementia, will become more widely available in the next 10 years. The increase in the availability of these procedures poses moral, social and ethical dilemmas, in addition to an arguable additional economic burden in that the cost of the procedures themselves might be offset by decreased costs of care, and this could be very important in some health care systems which are hard-pressed for economic resources.

Although CSF diversion is a therapeutic intervention with clear cut indications in the medical context, there are theoretical reasons to suggest that other procedures may be explored in an attempt to enhance the cognitive functioning of otherwise healthy individuals and slow the effects of ageing (much as we now use Ritalin and the anticholinesterases). In addition, the rapid development of safe electrical implant technologies in the field of psychosurgery is likely to lead to new insights regarding the feasibility of brain enhancement technology. All these developments pose ethical, moral, legal and socio-economic dilemmas. These quandaries are in many ways analogous to those posed by the non-medical use of cognitive enhancing pharmaceuticals (Greely et al., 2008; Racine & Forlini, 2009). However, neurosurgical strategies also pose additional unique dilemmas and some of these will be discussed in the following pages. We will start by a historical overview of psychosurgery and subsequently discuss ethical and legal aspects of potential non-surgical and surgical neuromodulation for enhancement in healthy individuals.