The Neuroanatomy of Emotion by Dr T M Jenkins – 21st October 2019

Dr Tom Jenkins is a con­sult­ant neur­o­lo­gist and Senior Clinical Lecturer in Neurology at the Royal Hallamshire Hospital in Sheffield.

He observed that the dif­fer­ence between heart and mind is that the heart is just a pump whereas everything comes from the brain.  The brain is the sphere of interest to the neur­o­lo­gist.  Tom gave an example of his pro­fes­sional life: One Monday even­ing a 62 year old lady was admit­ted to the Hallamshire Hospital with sudden epis­odes of intense fear last­ing seconds and occur­ring in full con­scious­ness.  This had been hap­pen­ing once every few weeks but was increas­ing in fre­quency recently. The neur­o­lo­gical exam­in­a­tion was normal.  When asked the audi­ence was rather reti­cent to sug­gest a reason. Tom explained that fear sug­gests a prob­lem with the amy­g­dala part of the brain. An MRI showed a tumour to the side of the amy­g­dala caus­ing focal seizures. He described this as an example of “neuroana­tom­ical loc­al­isa­tion in clin­ical neur­o­logy”, and his audi­ence was reminded that Stumperlowe Probus has had some very bright speak­ers and Tom was one of them.

Tom con­tin­ued to give a brief intro­duc­tion to clin­ical neur­o­logy with a focus on the limbic system.  Clinical Neurology is the branch of medi­cine con­cerned with dis­orders of the brain & nervous system.  Tools at the Neurologist’s dis­posal are his­tory (what people say); exam­in­a­tion and invest­ig­a­tions.

History includes the memory clinic.  The rich­ness of detail shows how func­tional a patient may be or how dimin­ished due to demen­tia.  Who comes to see the neur­o­lo­gist – if a patient is accom­pan­ied by someone this may be a sign of demen­tia.  If a patient turns their head away during con­ver­sa­tion is another demen­tia sign.  Conversational ana­lysis where the lan­guage struc­ture is examined is another aspect.

Examination is a tool.  It’s required when his­tory doesn’t help.  As an example, a 70-year-old man was admit­ted to hos­pital in a con­fused state.  He couldn’t give an account of the prob­lem and his family said he was walk­ing round bump­ing into things.  A neur­o­lo­gical exam­in­a­tion of his limbs was normal.  He was not dys­phasic (speech defi­ciency).  He got up to go to the loo and it became appar­ent that he could not see.  However, his ocular exam­in­a­tion was normal.  He was found to be con­fab­u­lat­ing to com­pensate for his lack of vision.  The prob­lem was cor­tical blind­ness due to a stroke.  He had com­pletely lost his sight and could not remem­ber having sight.

Investigation is a large field of pro­ced­ures.  Lumber punc­ture or spinal tap has been around for some time.  MRI scans are very import­ant. Recently there has been an ima­ging revolu­tion in neur­os­cience with 3D images on com­puter.

Neurophysiology is con­cerned with record­ing and inter­pret­ing elec­trical sig­nals from the nervous system. It is import­ant in the eval­u­ation of peri­pheral nerve and brain func­tion, often a key ele­ment in the dia­gnosis and assess­ment of dis­eases of the nervous system, such as epi­lepsy, muscle and peri­pheral nerve dis­ease, sleep dis­orders or mon­it­or­ing of nerve func­tion.  Electrodes are placed over the scalp to record activ­ity.  The pro­cess is called an elec­tro­en­ceph­al­o­gram (EEG).

 

The Limbic System is a set of brain struc­tures loc­ated on top of the brain­stem and buried under the cortex. Limbic system struc­tures are involved in many of our emo­tions and motiv­a­tions, par­tic­u­larly those that are related to sur­vival such as fear and anger.  There are two per­cep­tual areas: Memory and Emotion.  The latter encom­passes jeal­ousy; anger; envy; embar­rass­ment; dis­gust; fear; humour: love. These two areas com­bine to give drive-related beha­viour like: to avoid danger; to fight for sur­vival; to pass genes on; to pro­tect one’s young and to gain bene­fits of social group­ing.  These are related to evol­u­tion­ary bene­fit.  Tom went into some detail about memory and demen­tia and the dif­fer­ent areas of the brain involved.

For his audience’s age group, Tom’s talk was all too per­tin­ent.  It gave a struc­tured back­ground to a big sub­ject that few laymen will be versed in.  Tom’s grasp of the sub­ject was most impress­ive.