This document provides an overview of forensic psychiatry and defines common psychiatric terms and symptoms of mental illness that are relevant to the legal system. It describes normal mental functions and defines key concepts like insanity, mental impairment, delirium, delusions, hallucinations, illusions, impulses, obsessions, and lucid intervals. It distinguishes between psychoses and neuroses and provides examples of specific delusions, hallucinations, and impulses. Important medicolegal concepts are also outlined, such as distinguishing responsibility during lucid intervals in insanity versus head injury.

1. FORENSIC PSYCHIATRY
DR.P.PRASANNA
ASSISTANT PROFESSOR
DEPARTMENT OF FORENSIC MEDICINE

2. Normal functions of the mind
 Thinking
 Memory
 Awareness
 Perception
 Attitude
 Intelligence
 Behaviour
 Emotions
 Judgment
 Orientation
 Insight

3. • Psychiatry - study, diagnosis and treatment of mental illness.
• Forensic psychiatry - deals with application of psychiatry in the
administration of justice.
• Insanity (mental illness) or Unsoundness of mind can be defined as
a disease of the mind in which there is derangement of the mental or
emotional processes.
• The law is mostly frequently concerned with “mental impairment”
and not “mental illness”

4. SYMPTOMS OF MENTAL ILLNESS

5. • DELIRIUM: disturbance of consciousness in which orientation is impaired,
critical faculty is blunted or lost and thought content is irrelevant or
inconsistent.
• DELUSION : is a false belief in something which is not a fact, and the belief
persists even after its falsity has been clearly demonstrated.
• Its under the control of emotional but not rational force.

7. • TYPES OF DELUSION:
1. Grandeur
2. Persecution
3. Reference
4. Influence
5. Infidelity
6. Self – reproach
7. Nihilistic
8. Hypochondrical
9. Other types

8. •Medicolegal importance
1. Is never an isolated disorder
2. Person - not responsible
3. Suicide is at major risk
4. May be combination of suicide and homicide.

9. •Erotomania: is a delusion in which a person believes that someone is
deeply in love with him/her.
• The erotomanic develops an obsession for the person and starts believing that
the other person is reciprocating.
• The object is usually of a higher status, famous superior at work but can also be
a complete stranger.

10. • HALLUCINATION: false sense perception, without any external object or
stimulus to produce it.

11. • Types:
1. Visual
2. Auditory
3. Olfactory
4. Gustatory
5. Tactile
6. Psychomotor
7. Command
8. Microptic or macroptic
9. Sexual

12. ILLUSION
• Illusion is a false interpretation of an external object or stimulus which
has a real existence.

13. IMPULSE
• This is a sudden irresistible force compelling a person to do the
conscious performance of some action without motive or forethought.
• Usually seen in epilepsy. dementia, acute mania.

14. TYPES
• Kleptomania
• Pyromania
• Mutilomania
• Dipsomania
• Sexual Impulses Including Sexual Perversions
• Suicidal And Homicidal Impulses.

15. OBSESSION
• A single idea, thought or emotion constantly entertained by the
person which he recognizes as irrational, but persists in spite of
all efforts to drive it out of his mind.
• It’s a disorder of content of thought.

16. • Lucid interval : this is a period occurring in insanity, during which all the
symptoms of insanity disappear completely.
• Lucid Interval Is Also Seen In Head Injury.
• During This Period He Will Not Be Completely Held Responsible For His
Criminal Acts.

17. Difference Between Lucid Interval In Insanity And
Head Injury
Trait Insanity Head injury
History Of Insanity Present. History Of Head Injury
Preceeding Symptoms OF Insanity Present Of Concussion
Following Symptoms Of Insanity Cerebral Irritation And
Compression Of Brain
Occurrence Frequent Only Once

18. Some Common Terms Used In Psychiatry
• Affect: Subjective And Immediate Experience Of Emotion At A Given Time
• Mood: Pervasive Emotion Or Feeling Which Is Sustained.
• Insight: Is To Do With Awareness Of One’s Own Mental Condition.
• Phobia: Is An Irrational Fear Of An Object, Situation Or Activity.
• Confabulation :Is A False Memory That The Patient Believes To Be True.

19. • Mutism: Complete Loss Of Speech.
• Psychopath: Psychopath Is A Person Who Is Neither Insane Nor Mentaly Ill,
But Fails To Conform To The Normal Standards Of Behavior.
• Neurasthenia: It Is Condition Of Nervous Exhaustion Due To Physical Or
Mental Conditions.
• Oneiric States: It Is A Dream Like State Which May Last For Days Or Weeks.
The Patient Suffers From Confusion, Amnesia, Illusions, Hallucination,
Disorientation Agitation And Anxiety.

20. • PSYCHOSES: characterized by withdrawal from reality, and living in a world
of fantasy.
• NEUROSES: The patient suffers from emotional or intellectual disorders, but
he does not lose touch with reality
• Dementia: Is A Condition In Which There Is Degeneration Of Mental Faculties
After They Have Been Fully Developed. Eg: Alzhimers Disease, Picks Disease,
Huntington's Chorea, Creutzfeldt-Jakob Disease.

21. Differences Between Psychoses And Neuroses
Trait Psychosis Neurosis
Nature Disease entity with physical
basis which is determined
genetically
Reaction to stressful
circumstances due to adverse
childhood experiences
Severity Major minor
Empathy Absent Present
Contact with reality Absent Present
Insight Absent Present