Concepts in the Light of Evolution~Memory~

Jakob KaiserSilke KärcherRafaela Wahl

University of Osnabrueck 1

Remember….

University of Osnabrueck 2

Concepts

Learned Innate: e. g. Instinctive fear of snakes and spiders

Experience

Perception

It is through repeatedly perceiving salient objects and states of affairs of certain types, that the animal comes to have regular patterns of learned behaviour in relation to them.

It seems reasonable to suppose that (apart from any innate concepts) an animal only has concepts of those types of things that it has at some time perceived (and only some of those).

Evolutionary accidents

Products of natural selection

Remember….

University of Osnabrueck 3

Concepts

Learned Innate: e. g. Instinctive fear of snakes and spiders

Experience

Perception

It is through repeatedly perceiving salient objects and states of affairs of certain types, that the animal comes to have regular patterns of learned behaviour in relation to them.

It seems reasonable to suppose that (apart from any innate concepts) an animal only has concepts of those types of things that it has at some time perceived (and only some of those).

Evolutionary accidents

Products of natural selection

Memory

Overview

Object permanence

From Perception to Memory Perception Sensoric Memory Working Memory Long-Term Memory

Semantic vs. Episodic Memory One or two? Do animals have episodic Memory? Episodic Memory and Language

Closing Remarks

Object Permanence

For us, and for all higher animals, objects exist. We perceive the world as structured into patterns Objects have clearly defined boundaries

separating them from their surroundings.

Object Permanence

Object Permanence

There are differences in the degree among mammals and birds with . regards to how much information about the nature of objects is . reflected in the animal's behaviour. (Hurford, 2007, p 38).

Some animals, especially higher vertrebates, can keep an object in . mind even when it has disappeared from sight.

Knowing that an object is permanent takes a cognitive step beyond . the simple perception of the object. → → MEMORY!MEMORY!

Object Permanence

From Perception to Memory

Perception

After all [...] transformation persistant correlations are seen between overall patterns of activation in various brain centers and classes of external stimuli. It seems reasonable to say that [...] firing patterns representrepresent the classes of input stimuli (Hurford, 2007, p.52).

Representation in the brain

From Perception to Memory

Sensory Memory

Sensory memory Sensory memory is the retention for brief periods of time . of the effects of sensory stimulation (Goldstein, 2008, p. 141).

From Perception to Memory

Working Memory

Working Memory

= Short term memory Conscious (!!)Conscious (!!) representation of sensoric information Short term storage Limited amount of information

→ things are remembered as long as there is activation→ forgetting: decline of activation→ online processing

Working Memory

Biologically, short-term memory is a temporary potentiation of neural connections that can become long-term memory through the process of rehearsal and meaningful association.

From Perception to Memory

Longterm Memory

Knowledge of organism about the world (and itself) Capacity potentially unlimited (in humans) Can store info for a time span anywhere from minutes to . a life time Information can be remembered

Longterm Memory

An Example

1. Sensory perception (smell, vision, sounds..)

2. Unifying different sensory modalities: auditory, visual, . olfactory, tactile properties into a single concept → mentaly . holistic cat

3. Storage of the concept

4. In humans: tying to a linguistic expression “CAT“

→ In order to have stable concepts,have stable concepts, there has to be a way to store them

How are concepts related to memory?

Longterm Memory

(from Goldstein, 2008, p. 188).

Episodic and Semantic Memory

Episodic Memory

So many years ago... But it feels like it was yesterday.

Mental Time Travel

Episodic Memory

I can still feel my heart beating when I think of it.

reliving of certain emotions and perception possible

Episodic Memory

I am the man who once asked this beautiful lady for a date.

relationship between episodic memory and self-awareness?

Episodic Memory

? wuff ?

Important for our topic: What does the dog remember now?

?

?

Semantic Memory

Semantic memorySemantic memory refers to the memory of meanings, understandings, and other concept-based knowledge unrelated to specific personal experiences.

The conscious recollection of factual information and general knowledge about the world is generally thought to be independent of context and personal relevance (Canadian Institue of Neuroscience, 2002).

Semantic Memory

Semantic memory can generalize over single instances.

Generalization is a very important mechanism for learning.

Semantic memory can be used for the storage of concepts.

Semantic Memory

The value of generalizing is in data-compression. You don’t need to burden your memory with all those formative experiences if you can distil what is important in them into an economical set of principles automatically guiding your future behaviour (Hurford, 2007, p. 65).

If semantic memory is so cool - do we really need episodic memory??

Semantic vs. Episodic Memory

In fact a very large number of inferences can be drawn from any observed event, and one may ask whether it is economical to do a lot of instant inferencing and throw away the premiss (a representation of the event). The alternative would be not to do any on-the-spot inferencing and to store the raw observed information about the event [...], leaving any inferencing for later, whenever it may be needed (Hurford, 2007, p. 65).

Hurford’s answer: Episodic Memory increases our inferential flexibility!

Semantic vs. Episodic Memory

Semantic memory can be enhanced with the aid of episodic memory (self reference helps storage).

Semantic memory can influence our experience of episodes by influencing attention.

Semantic vs. Episodic Memory

The manner in which information is registered in the episodic and semantic systems is highly similar— there is no known method of readily encoding information into an adult’s semantic memory without putting corresponding information in episodic memory or vice versa… (Wheeler et al., 1997, p. 333).

Since semantic and episodic memory seem to be so tightly related,

is there proof that they are dissociated?

Two different kinds of memory

Patient K.C.

Motorcycle accident, amnesia

No episodic memory, but semantic memory is intact

Two different kinds of memory

Patient K.C.

[H]is ability to make use of knowledge and experiences from the time before his accident shows a sharp dissociation between semantic and episodic memory. A good deal of his general knowledge of the world, including knowledge about himself, is preserved, but he is incapable of recollecting any personally experienced events (Rosenbaum et al., 2005).

Do animals have episodic memory?

Episodic Memory in Animals

Tulving […] believes that animals do not have episodic memory, not even higher primates such as chimpanzees and gorillas. To him, they have only semantic memory. They always live for the moment, lacking the human ability to travel back and forth in time in their mind. That is, they cannot remember what they did yesterday or imagine what they will do tomorrow. This capacity for mental time travel seems to be unique to humans. Animals do not have this capacity, nor do some people who have

suffered a certain type of brain damage (science.ca).

No Episodic Memory in Animals?

Sceptisism:

Which of the following propositions was stored by the squirrel – seeing the nuts in the cup, did it just store a static fact (nuts are in the second cup from the left) or did it store the experience of finding the nuts in the cup so it could relive the experience later on to find the nuts? (adapted from Hurford, 2007, p.72)

Episodic Memory in Animals

I remember that there must be a treat under the disk.

I remember seeing how someone put a treat under this disk.

Static fact (semantic)

Experience (episodic)

Episodic Memory in Animals

It is difficult to proove episodic memory in non-human animals, since . they cannot talk about it.

Therefore, researchers talk about “episodic-like memories“

“Episodic-like memory“ means that the animal need not be 'aware', in a . fully human sense, of the recalled event.

It is domain limited to events that have a strong importance for the . animal's life (f.e. food, predators).

Episodic Memory in Animals

A “New” Kind of Memory

Hurford: Episodic memory is closely connected with the . ability to use language → both seem to be pretty new in the light of evolution.

Linked to the ideas of self and consciousness, there may be a close connection between language and episodic memory. Most people's 'first memories' of the earliest experiences in their lives are of events happening after about two years of age, after the onset of connected language (Hurford, 2007, p. 69).

A “New” Kind of Memory

One of the most obvious uses of language is to give each other new information, to tell people about events that we know happened, but that they don't know about. […]If we didn't have episodic memories, we wouldn't have much to tell each other. By contrast, uttering analytic sentences, such as lions are animals, is pretty useless in factual communication, though it can serve a purpose in educating the young about the commonly held meaning of words (Hurford, 2007, p 85).

Closing Remarks

Human memory is a highly developed system with several components → Animals vary in their degree of memory-abilities

In the realm of the long-term memory, two systems are very important for the conceptualization of the environment:

→ semantic memory→ episodic memory

Semantic memory and episodic memory are tightly conntected; yet they are two dissociated systems.

Many scientists believe that there is no episodic memory in animals; however, some animals are discribed as having “episodic-like“ memory.

Evolution of episodic memory seems to be related to the developement of language.

University of Osnabrueck