1939

Michael S. Gazzaniga

ConfabulationThe interpreterCerebral lateralization

in Black box, Split brain

Michael S. Gazzaniga (b. 1939), American cognitive neuroscientist who co-coined the term "cognitive neuroscience." Director of the SAGE Center for the Study of the Mind at the University of California, Santa Barbara; his career was built on split-brain research, beginning with Roger Sperry (Nobel Prize, 1981) and continuing with Joseph LeDoux. Who's in Charge? (2011) is a trade adaptation of his Gifford Lectures.

Stake§

Reputational and, in part, philosophical — the left-hemisphere "interpreter" is his own, originated in the split-brain research, and the book uses it to argue a determinism-compatible account of responsibility, so he writes as the originator and an advocate of the conclusions he draws from it.

Gazzaniga's contribution to this topic is the interpreter: a left-hemisphere module that supplies reasons for behaviour whose real cause it cannot see. In the classic split-brain demonstration the speaking hemisphere, with no access to the instruction the other received, invents a plausible reason rather than reporting ignorance. The mechanism is the neuroscientific sibling of Nisbett and Wilson's confabulation and of Haidt's post-hoc moral reasoning — the same gap between a decision and its stated reason at three levels.

Gazzaniga is the link between this topic and the split-brain topic, where the interpreter was found. He ran the human commissurotomy cases from the 1960s — the 1967 Scientific American account, the 1978 Integrated Mind with LeDoux where the interpreter was first demonstrated, and the 2000 and 2005 syntheses — alongside Sperry, who read the same split brains as two minds. The interpreter he named there is the confabulation this topic turns on.

Works in this corpus§

their concepts on the territory — a bridge across multiple topics
Cerebral lateralizationCerebral lateralization ConfabulationConfabulation The interpreterThe interpreter

3 concepts · spans multiple topicsopen the full territory →

excerpts

The human brain is actually two brains each capable of advanced mental functions. When the cerebrum is divided surgically, it is as if the cranium contained two separate spheres of consciousness.
The Split Brain in Man (1967)

The magazine's framing of the finding — the popular form of the [[concept:unity-of-consciousness|two-consciousnesses]] reading that [[source:sperry-1968-hemisphere-deconnection|Sperry]] stated for the field a year later. (This is the article's standfirst, captured from the publisher page; the paywalled body carries the experiments.)

on Unity of consciousness

These phenomena appear to be related to our left hemisphere's interpreter, a device that allows us to construct theories about the relationship between perceived events, actions and feelings.
Cerebral specialization and interhemispheric communication: Does the corpus callosum enable the human condition? (2000)

Gazzaniga's working definition of [[concept:the-interpreter|the interpreter]] — a narrating device that builds theories linking what we perceive, do, and feel. The same construct the [[topic:black-box|black-box topic]] meets as [[concept:confabulation|confabulation]].

on The interpreter

The interpreter sustains a running narrative of our actions, emotions, thoughts, and dreams. The interpreter is the glue that keeps our story unified and creates our sense of being a coherent, rational agent.
Cerebral specialization and interhemispheric communication: Does the corpus callosum enable the human condition? (2000)

The interpreter cast as the source of felt selfhood — the thing that makes a modular, divided brain feel like one continuous person. Bears on [[concept:unity-of-consciousness|unity of consciousness]].

on The interpreter, Unity of consciousness

Gazzaniga and LeDoux introduced the concept of a left brain 'interpreter', which creates a schema or 'story' about events that goes beyond the actual available information. They postulated that the interpreter underlies the human drive to seek explanations for why events occur.
Forty-five years of split-brain research and still going strong (2005)

Gazzaniga's own retrospective dating of [[concept:the-interpreter|the interpreter]] to the [[source:gazzaniga-ledoux-1978-integrated-mind|1978 work]] with LeDoux, and a clean statement of the claim — the narrator goes beyond the evidence to satisfy a drive to explain.

on The interpreter